A power supply method, device, system, medium, and product for a solar thermal energy storage system.

Abstract

This application provides a power supply method, device, system, medium, and product for a photovoltaic thermal energy storage system, relating to the field of photovoltaic power generation. The method obtains the state of charge (SOC) of the energy storage system and the output capacity of the shared bus capacitor inertia. When the energy storage capacity is sufficient and the bus inertia support capacity is normal, multiple power sources are used to power the system. However, under extreme conditions where the energy storage capacity is insufficient and the shared bus capacitor inertia support capacity decreases, the system no longer relies solely on electrical side resources. Instead, it combines the temperature of the heat transfer medium, the thermal storage state, and the heat demand on the thermal side to adjust the operation of the thermal side and output compensating power. Multiple power sources and thermal side compensating power are jointly injected into the shared bus capacitor, compensating for the power supply gap caused by insufficient energy storage resources and decreased capacitor buffer capacity. This improves the power supply reliability and power quality of the photovoltaic thermal energy storage system under multi-source fluctuations, sudden load changes, and extreme conditions, avoiding problems of power quality degradation and power outages.

Description

Technical Field

[0001] This application relates to the field of photovoltaic power generation, and in particular to a power supply method, device, system, medium and product for a photovoltaic thermal energy storage system. Background Technology

[0002] With increasing grid volatility and rising user demands for energy comfort and emergency power supply capabilities, the power supply capacity of solar thermal energy storage systems has become an important foundation for coordinating energy supply and demand and supporting low-carbon development goals.

[0003] In existing technologies, solar thermal energy storage systems typically employ a power supply architecture where the power grid serves as the primary power source and the energy storage system acts as an auxiliary backup power source. The alternating current (AC) output from the power grid is converted into direct current (DC), which is then combined with the DC output from the energy storage system and fed into the system's DC bus. The combined DC power then supplies load equipment such as air conditioning compressors and fans to ensure the continuous and stable operation of the solar thermal energy storage system.

[0004] However, existing technologies suffer from low power supply reliability in solar thermal energy storage systems. When dealing with fluctuations in power supply from multiple sources, sudden load changes, or extreme operating conditions, existing technologies rely too heavily on the energy storage capacity and capacitor inertia. This makes it difficult to maintain stable power output when energy storage resources are insufficient or buffering capacity is reduced, easily leading to degraded power quality or even power outages. Summary of the Invention

[0005] This application provides a power supply method, device, system, medium, and product for a photovoltaic thermal energy storage system, in order to solve the problem of low power supply reliability in existing photovoltaic thermal energy storage systems.

[0006] In a first aspect, embodiments of this application provide a power supply method for a photovoltaic thermal energy storage system, including:

[0007] The state of charge (SOC) of various electrical energy and energy storage systems from multiple power sources and the inertia output capability of a shared bus capacitor are obtained; wherein, the inertia output capability is used to represent the ability of the shared bus capacitor to suppress voltage fluctuations across the shared bus capacitor.

[0008] When the state of charge is higher than or equal to a preset state threshold and the inertia output capability is higher than or equal to a preset capability threshold, all the various electrical energies are injected into the shared bus capacitor, and the shared bus capacitor supplies power to the photovoltaic thermal energy storage system; wherein, the shared bus capacitor is electrically connected to the multiple power sources;

[0009] When the state of charge is lower than the preset state threshold and the inertia output capability is lower than the preset capability threshold, the heat medium temperature of the photovoltaic thermal energy storage system, the thermal storage state of the preset thermal energy storage device, and the heat demand of the preset heat load are obtained, and an inertia compensation command is generated based on the heat medium temperature, the thermal storage state, and the heat demand; wherein, the inertia compensation command is used to adjust the operating state of the preset thermal side of the photovoltaic thermal energy storage system to provide compensation power for the shared bus capacitor;

[0010] The various types of electrical energy and the compensation electrical energy are all injected into the shared bus capacitor, and the shared bus capacitor supplies power to the photovoltaic thermal energy storage system; wherein, the compensation electrical energy refers to the electrical energy released or converted by the preset thermal side after the inertia compensation command is executed, and the shared bus capacitor is electrically connected to the preset thermal side.

[0011] In one possible design, after injecting the various electrical energies and the compensation electrical energy into the shared bus capacitor and supplying power to the photovoltaic thermal energy storage system through the shared bus capacitor, the design further includes:

[0012] When the state of charge is lower than the preset state threshold and the inertia output capability is higher than the preset capability threshold, a pre-compensation command is generated based on the heat medium temperature, the heat storage state, and the heat demand. The pre-compensation command instructs the preset thermal side to reduce the operating power of the preset heat load when the state of charge is lower than the preset state threshold and the inertia output capability is higher than the preset capability threshold, so that the energy saved by the preset thermal side can be reserved for the shared bus capacitor. The preset heat load is set on the preset thermal side.

[0013] When the state of charge is higher than the preset state threshold and the inertia output capability is lower than the preset capability threshold, an energy storage compensation command is generated based on the capability gap between the inertia output capability and the preset capability threshold; wherein, the energy storage compensation command is used to instruct the energy storage system to discharge to the shared bus capacitor with a power greater than the preset rated discharge power of the energy storage system.

[0014] In one possible design, generating an energy storage compensation command based on the capacity gap between the inertia output capability and the preset capability threshold includes:

[0015] Obtain the real-time voltage waveform of the shared bus capacitor, and extract the dynamic load characteristics of each electrical device in the photovoltaic thermal energy storage system from the real-time voltage waveform;

[0016] Based on the dynamic load characteristics, identify the types of multiple electrical devices currently in operation in the solar thermal energy storage system and the instantaneous power demand curves corresponding to each electrical device, and retrieve the power supply priority of each electrical device from the preset device priority configuration table according to the type of each electrical device.

[0017] Based on the instantaneous power demand curve, the capacity deficit, and the power supply priority of each electrical device, an energy storage compensation instruction is generated; wherein, the energy storage compensation instruction is used to instruct the energy storage system to discharge to the shared bus capacitor with a power greater than the preset rated discharge power, and to make the time-domain waveform of the discharge power preferentially match the instantaneous power demand curve of the electrical device with the highest power supply priority.

[0018] According to the energy storage compensation command, the electrical energy output by the energy storage system is injected into the shared bus capacitor with a time-domain waveform that matches the instantaneous power demand curve of the electrical device with the highest power supply priority, so that when the shared bus capacitor discharges to each electrical device, the shared bus capacitor prioritizes ensuring the power demand of the electrical device with the highest power supply priority.

[0019] In one possible design, the multiple power sources include a photovoltaic system, and the process of injecting all the various electrical energy sources into the shared bus capacitor and supplying power to the photovoltaic thermal energy storage system through the shared bus capacitor includes:

[0020] Based on the state of charge, the inertia output capability, and the real-time load power of the photovoltaic thermal energy storage system, a dynamic power allocation model is established on the power side; wherein, the dynamic power allocation model on the power side is used to determine the injection priority and power ratio of the multiple power supply sources to inject power into the shared bus capacitor;

[0021] Based on the aforementioned dynamic power allocation model, a power allocation command is generated. This command is used to prioritize injecting the power output from the photovoltaic system into the shared bus capacitor when the voltage fluctuation rate of the shared bus capacitor is lower than a preset rate threshold, and to configure the energy storage system in a fast-response standby state so that the energy storage system immediately discharges when the voltage fluctuation rate of the shared bus capacitor increases. The power allocation command is also used to prioritize injecting the power output from the energy storage system into the shared bus capacitor when the voltage fluctuation rate of the shared bus capacitor is higher than the preset rate threshold, and to configure the photovoltaic system in a continuous power supply standby state so that the photovoltaic system continuously injects power when the voltage fluctuation rate of the shared bus capacitor decreases.

[0022] According to the power allocation instruction, the various types of power are injected into the shared bus capacitor in batches according to the injection priority and the power allocation ratio.

[0023] In one possible design, injecting the various electrical energies into the shared bus capacitor in batches according to the injection priority and the power allocation ratio based on the power side allocation instruction includes:

[0024] The real-time voltage value and voltage change trend of the shared bus capacitor are obtained, and a waveform shaping model is constructed based on the real-time voltage value and voltage change trend; wherein, the waveform shaping model is used to match the time-varying law of the injected power of the various electrical energies with the voltage fluctuation phase of the shared bus capacitor;

[0025] Based on the various electrical energy sources and the waveform shaping model, a waveform shaping injection command is generated; wherein, the waveform shaping injection command is used to make the injected power decrease as the voltage increases when the voltage of the shared bus capacitor is in the rising phase, and to make the injected power increase as the voltage decreases when the voltage of the shared bus capacitor is in the falling phase.

[0026] According to the waveform shaping injection command, the various electrical energies are injected into the shared bus capacitor in batches according to the injection priority and the power ratio, following the decreasing or increasing trend.

[0027] In one possible design, injecting the various electrical energy sources and the compensation electrical energy into the shared bus capacitor, and supplying power to the photovoltaic thermal energy storage system through the shared bus capacitor, includes:

[0028] The instantaneous phase feature and instantaneous amplitude feature of the real-time voltage waveform of the shared bus capacitor are obtained; wherein, the instantaneous phase feature is used to represent the phase angle of the real-time voltage waveform at the current moment, and the instantaneous amplitude feature is used to represent the amplitude of the real-time voltage waveform at the current moment;

[0029] Based on the instantaneous phase characteristics and the instantaneous amplitude characteristics, the various electrical energies and the compensation electrical energy are subjected to power conversion to obtain an orthogonal injection current that is orthogonal to the phase of the real-time voltage waveform. The orthogonal injection current is then injected into the shared bus capacitor so that the orthogonal injection current absorbs electrical energy at the peak moment of the shared bus capacitor voltage and releases electrical energy at the zero-crossing moment of the shared bus capacitor voltage. Herein, the orthogonal injection current refers to the injection current that is phased with the real-time voltage waveform by a preset angle.

[0030] In one possible design, the capability to acquire the state of charge of multiple electrical energy sources from multiple power supply sources, the inertia output capability of energy storage systems, and the shared bus capacitor includes:

[0031] The system acquires the various initial electrical energies output from the multiple power sources, the state of charge, and the inertia output capability.

[0032] Differential preprocessing is performed on the various initial electrical energies to obtain the various electrical energies; wherein, the differential preprocessing is used to eliminate the differences between each electrical energy and the preset rated parameter requirements of the shared bus capacitor, so that the various electrical energies are adapted to the preset rated parameter requirements.

[0033] In one possible design, the multiple power sources include a photovoltaic system, an energy storage system, and a power grid. The differentiated preprocessing of the multiple initial electrical energies to obtain the multiple electrical energies includes:

[0034] Obtain the bus voltage of the shared bus capacitor, the real-time maximum output power of the photovoltaic system, and the real-time power supply status of the power grid;

[0035] Based on the bus voltage, the state of charge, the real-time maximum output power, and the real-time power supply status, a virtual inertia model of the photovoltaic thermal energy storage system is constructed; wherein, the virtual inertia model is used to establish the coupling relationship between the energy absorbed or released by the shared bus capacitor per unit time and the voltage fluctuation rate across the shared bus capacitor;

[0036] Based on the virtual inertia model, the various initial electrical energies are preprocessed differently to obtain the various electrical energies.

[0037] In one possible design, the multiple initial electrical energies include a first electrical energy, a third electrical energy, and a fifth electrical energy; the multiple electrical energies also include a second electrical energy, a fourth electrical energy, and a sixth electrical energy; and the differential preprocessing of the multiple initial electrical energies to obtain the multiple electrical energies includes:

[0038] The first electrical energy is subjected to a maximum power point search to obtain the second electrical energy; wherein, the first electrical energy is the electrical energy output by the photovoltaic system;

[0039] The third electrical energy is subjected to voltage matching and power regulation to obtain the fourth electrical energy; wherein, the third electrical energy is the electrical energy output by the energy storage system;

[0040] The fifth electrical energy is converted from AC to DC and voltage matched to obtain the sixth electrical energy; wherein the fifth electrical energy is the electrical energy output by the power grid.

[0041] Secondly, embodiments of this application provide a power supply device for a photovoltaic thermal energy storage system, comprising:

[0042] The first acquisition module is used to acquire the state of charge of various electrical energy and energy storage systems output from multiple power sources and the inertia output capability of the shared bus capacitor; wherein, the inertia output capability is used to represent the ability of the shared bus capacitor to suppress voltage fluctuations across the shared bus capacitor.

[0043] The first injection module is used to inject the various electrical energies into the shared bus capacitor when the state of charge is higher than or equal to a preset state threshold and the inertia output capability is higher than or equal to a preset capability threshold, and to supply power to the photovoltaic thermal energy storage system through the shared bus capacitor; wherein, the shared bus capacitor is electrically connected to the multiple power sources;

[0044] The second acquisition module is used to acquire the heat medium temperature of the photovoltaic thermal energy storage system, the thermal storage state of the preset thermal energy storage device, and the heat demand of the preset heat load when the state of charge is lower than the preset state threshold and the inertia output capability is lower than the preset capability threshold. Based on the heat medium temperature, the thermal storage state, and the heat demand, the module generates an inertia compensation command. The inertia compensation command is used to adjust the operating state of the preset thermal side of the photovoltaic thermal energy storage system to provide compensation power for the shared bus capacitor.

[0045] The second injection module is used to inject the various types of electrical energy and the compensation electrical energy into the shared bus capacitor, and to supply power to the photovoltaic thermal energy storage system through the shared bus capacitor; wherein, the compensation electrical energy refers to the electrical energy released or converted by the preset thermal side after the inertia compensation command is executed, and the shared bus capacitor is electrically connected to the preset thermal side.

[0046] In one possible design, the power supply device for the photovoltaic thermal energy storage system further includes:

[0047] The first generation module is used to generate a pre-compensation instruction based on the heat medium temperature, the heat storage state, and the heat demand when the state of charge is lower than the preset state threshold and the inertia output capability is higher than the preset capability threshold; wherein, the pre-compensation instruction is used to instruct the preset thermal side to reduce the operating power of the preset heat load when the state of charge is lower than the preset state threshold and the inertia output capability is higher than the preset capability threshold, so as to reserve the electrical energy saved by the preset thermal side for the shared bus capacitor, and the preset heat load is set on the preset thermal side;

[0048] The second generation module is used to generate an energy storage compensation command based on the capacity gap between the inertia output capability and the preset capability threshold when the state of charge is higher than the preset state threshold and the inertia output capability is lower than the preset capability threshold; wherein, the energy storage compensation command is used to instruct the energy storage system to discharge to the shared bus capacitor with a power greater than the preset rated discharge power of the energy storage system.

[0049] In one possible design, the second generation module includes:

[0050] The first acquisition unit is used to acquire the real-time voltage waveform of the shared bus capacitor and extract the dynamic load characteristics of each electrical device in the photovoltaic thermal energy storage system from the real-time voltage waveform.

[0051] The identification unit is used to identify the types of multiple electrical devices currently in operation in the solar thermal energy storage system and the instantaneous power demand curves corresponding to each electrical device based on the dynamic load characteristics, and to retrieve the power supply priority of each electrical device from the preset device priority configuration table according to the type of each electrical device.

[0052] The first generation unit is used to generate an energy storage compensation instruction based on the instantaneous power demand curve, the capacity deficit, and the power supply priority of each electrical device; wherein, the energy storage compensation instruction is used to instruct the energy storage system to discharge to the shared bus capacitor with a power greater than the preset rated discharge power, and to make the time-domain waveform of the discharge power preferentially match the instantaneous power demand curve of the electrical device with the highest power supply priority.

[0053] The first injection unit is used to inject the electrical energy output by the energy storage system into the shared bus capacitor in a time-domain waveform that matches the instantaneous power demand curve of the electrical device with the highest power supply priority, according to the energy storage compensation command, so that when the shared bus capacitor discharges to each electrical device, the shared bus capacitor prioritizes ensuring the power demand of the electrical device with the highest power supply priority.

[0054] In one possible design, the plurality of power sources include a photovoltaic system, and the first injection module includes:

[0055] The first establishment unit is used to establish a dynamic power allocation model on the power side based on the state of charge, the inertia output capability, and the real-time load power of the photovoltaic thermal energy storage system; wherein, the dynamic power allocation model on the power side is used to determine the injection priority and power ratio of the multiple power supply sources injecting power into the shared bus capacitor;

[0056] The second generation unit is used to generate power allocation instructions based on the power-side dynamic allocation model. These instructions are configured to: inject the power output from the photovoltaic system into the shared bus capacitor when the voltage fluctuation rate of the shared bus capacitor is lower than a preset rate threshold; and configure the energy storage system in a fast-response standby state so that the energy storage system immediately discharges when the voltage fluctuation rate of the shared bus capacitor increases. Furthermore, when the voltage fluctuation rate of the shared bus capacitor is higher than the preset rate threshold, the instructions are configured to: inject the power output from the energy storage system into the shared bus capacitor when the voltage fluctuation rate of the shared bus capacitor is higher than the preset rate threshold; and configure the photovoltaic system in a continuous power supply standby state so that the photovoltaic system continuously injects power when the voltage fluctuation rate of the shared bus capacitor decreases.

[0057] The second injection unit is used to inject the various types of electrical energy into the shared bus capacitor in batches according to the injection priority and the power allocation according to the power side allocation instruction.

[0058] In one possible design, the second injection unit includes:

[0059] The first acquisition component is used to acquire the real-time voltage value and voltage change trend of the shared bus capacitor, and to construct a waveform shaping model based on the real-time voltage value and voltage change trend; wherein, the waveform shaping model is used to match the time-varying law of the injected power of the various electrical energies with the voltage fluctuation phase of the shared bus capacitor;

[0060] The first generation component is used to generate a waveform shaping injection command based on the multiple electrical energy sources and the waveform shaping model; wherein, the waveform shaping injection command is used to make the injected power decrease as the voltage increases when the voltage of the shared bus capacitor is in the rising phase, and to make the injected power increase as the voltage decreases when the voltage of the shared bus capacitor is in the falling phase.

[0061] The first injection component is used to inject the various electrical energies into the shared bus capacitor in batches according to the waveform shaping injection command, based on the injection priority and the power ratio, and following the decreasing or increasing trend.

[0062] In one possible design, the second injection module includes:

[0063] The second acquisition unit is used to acquire the instantaneous phase characteristics and instantaneous amplitude characteristics of the real-time voltage waveform of the shared bus capacitor; wherein, the instantaneous phase characteristics are used to represent the phase angle of the real-time voltage waveform at the current moment, and the instantaneous amplitude characteristics are used to represent the amplitude of the real-time voltage waveform at the current moment;

[0064] The conversion unit is used to perform power conversion on the various electrical energy sources and the compensation electrical energy according to the instantaneous phase characteristics and the instantaneous amplitude characteristics, to obtain an orthogonal injection current that is orthogonal to the phase of the real-time voltage waveform, and to inject the orthogonal injection current into the shared bus capacitor, so that the orthogonal injection current absorbs electrical energy at the peak moment of the shared bus capacitor voltage and releases electrical energy at the zero-crossing moment of the shared bus capacitor voltage; wherein, the orthogonal injection current refers to the injection current that is out of phase with the real-time voltage waveform by a preset angle.

[0065] In one possible design, the first acquisition module includes:

[0066] The third acquisition unit is used to acquire the various initial electrical energies output by the multiple power sources, the state of charge, and the inertia output capability;

[0067] A preprocessing unit is used to perform differentiated preprocessing on the various initial electrical energies to obtain the various electrical energies; wherein, the differentiated preprocessing is used to eliminate the differences between each electrical energy and the preset rated parameter requirements of the shared bus capacitor, so that the various electrical energies are adapted to the preset rated parameter requirements.

[0068] In one possible design, the multiple power sources include a photovoltaic system, an energy storage system, and a power grid, and the preprocessing unit includes:

[0069] The second acquisition component is used to acquire the bus voltage of the shared bus capacitor, the real-time maximum output power of the photovoltaic system, and the real-time power supply status of the power grid.

[0070] The first building component is used to construct a virtual inertia model of the photovoltaic thermal energy storage system based on the bus voltage, the state of charge, the real-time maximum output power, and the real-time power supply status; wherein, the virtual inertia model is used to establish the coupling relationship between the energy absorbed or released by the shared bus capacitor per unit time and the voltage fluctuation rate across the shared bus capacitor.

[0071] A preprocessing component is used to perform differentiated preprocessing on the various initial electrical energies based on the virtual inertia model to obtain the various electrical energies.

[0072] In one possible design, the plurality of initial electrical energies includes a first electrical energy, a third electrical energy, and a fifth electrical energy; the plurality of electrical energies includes a second electrical energy, a fourth electrical energy, and a sixth electrical energy; and the preprocessing component includes:

[0073] A search component is used to perform a maximum power point search on the first electrical energy to obtain the second electrical energy; wherein, the first electrical energy is the electrical energy output by the photovoltaic system;

[0074] A control component is used to perform voltage matching and power regulation on the third electrical energy to obtain the fourth electrical energy; wherein, the third electrical energy is the electrical energy output by the energy storage system;

[0075] A matching component is used to perform AC / DC conversion and voltage matching on the fifth electrical energy to obtain the sixth electrical energy; wherein the fifth electrical energy is the electrical energy output by the power grid.

[0076] Thirdly, embodiments of this application provide a power supply system for a photovoltaic thermal energy storage system, including: multiple power sources, an energy storage system, a shared bus capacitor, a control module, and a preset thermal side;

[0077] The multiple power sources are used to output various types of electrical energy;

[0078] The energy storage system is used to store electrical energy;

[0079] The shared bus capacitor is electrically connected to the plurality of power sources and the energy storage system respectively. The shared bus capacitor is used to receive and store the electrical energy output by the plurality of power sources and to supply power to the photovoltaic thermal energy storage system. The shared bus capacitor has an inertia output capability, which is used to represent the ability of the shared bus capacitor to suppress voltage fluctuations across the shared bus capacitor.

[0080] The control module is used to acquire the state of charge of the energy storage system, the inertia output capability of the shared bus capacitor, and when the state of charge is lower than a preset state threshold and the inertia output capability is lower than a preset capability threshold, acquire the heat medium temperature of the solar thermal energy storage system, the thermal storage state of the preset thermal storage device, and the heat demand of the preset heat load.

[0081] The control module is further configured to, when the state of charge is higher than or equal to a preset state threshold and the inertia output capability is higher than or equal to a preset capability threshold, control the multiple power sources to inject various types of electrical energy into the shared bus capacitor; and when the state of charge is lower than the preset state threshold and the inertia output capability is lower than the preset capability threshold, generate an inertia compensation command based on the heat medium temperature, the heat storage state, and the heat demand; wherein, the inertia compensation command is used to adjust the operating state of the preset thermal side to provide compensation electrical energy for the shared bus capacitor;

[0082] The preset thermal side is electrically connected to the shared bus capacitor and the control module. The preset thermal side is used to receive the inertia compensation command sent by the control module and respond to the inertia compensation command to adjust its own operating state, release or convert compensation energy, inject the compensation energy into the shared bus capacitor, and cooperate with the various electrical energy output by the multiple power sources to supply power to the photovoltaic thermal energy storage system through the shared bus capacitor.

[0083] Fourthly, embodiments of this application provide a photovoltaic-thermal energy storage integrated power supply system, including: a preset thermal storage device, a preset heat load, a photovoltaic-thermal energy storage system, and a power supply system for the photovoltaic-thermal energy storage system as described in the third aspect;

[0084] The power supply system of the photovoltaic thermal energy storage system is electrically connected to the preset thermal energy storage device, the preset heat load, and the photovoltaic thermal energy storage system. The power supply system of the photovoltaic thermal energy storage system is used to obtain the thermal energy storage status of the preset thermal energy storage device and the heat demand of the preset heat load, and generate an inertia compensation command based on the thermal energy storage status and heat demand. The compensation power is supplied through the preset thermal side, and the power is supplied to the preset thermal energy storage device, the preset heat load, and the photovoltaic thermal energy storage system. The inertia compensation command is used to adjust the operating status of the preset thermal side to provide compensation power to the preset thermal energy storage device, the preset heat load, and the photovoltaic thermal energy storage system.

[0085] The preset thermal storage device is used to store the thermal energy generated by the photovoltaic thermal storage system and to feed back the thermal storage status of the preset thermal storage device to the power supply system of the photovoltaic thermal storage system.

[0086] The preset heat load is used to consume the heat energy generated by the photovoltaic thermal energy storage system, and the heat demand of the preset heat load is fed back to the power supply system of the photovoltaic thermal energy storage system.

[0087] Fifthly, embodiments of this application provide a computer-readable storage medium storing computer-executable instructions, which, when executed by a processor, are used to implement the power supply method of the photovoltaic thermal energy storage system as described in any of the first aspects.

[0088] In a sixth aspect, embodiments of this application provide a computer program product, including a computer program, which, when executed by a processor, is used to implement the power supply method for the photovoltaic thermal energy storage system as described in any of the first aspects.

[0089] This application provides a power supply method, device, system, medium, and product for a photovoltaic thermal energy storage system. By acquiring the state of charge of the energy storage system and the output capacity of the shared bus capacitor inertia, when the energy storage capacity is sufficient and the bus inertia support capacity is normal, the system is powered by multiple sources of electrical energy. However, under extreme conditions where the energy storage capacity is insufficient and the shared bus capacitor inertia support capacity decreases, the system no longer relies solely on electrical side resources. Instead, it combines the temperature of the heat transfer medium, the thermal storage state, and the heat demand on the thermal side to adjust the operation of the thermal side and output compensating electrical energy. The multi-source electrical energy and the thermal side compensating electrical energy are jointly injected into the shared bus capacitor, making up for the power supply gap caused by insufficient energy storage resources and decreased capacitor buffer capacity. This improves the power supply reliability and power quality of the photovoltaic thermal energy storage system under multi-source fluctuations, load changes, and extreme conditions, avoiding problems such as power quality degradation and power outages. Attached Figure Description

[0090] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0091] Figure 1 A schematic diagram illustrating an application scenario of the power supply method for the photovoltaic thermal energy storage system provided in this application embodiment;

[0092] Figure 2 A flowchart illustrating the power supply method for the photovoltaic thermal energy storage system provided in this application embodiment. Figure 1 ;

[0093] Figure 3 A flowchart illustrating the power supply method for the photovoltaic thermal energy storage system provided in this application embodiment. Figure 2 ;

[0094] Figure 4 A schematic diagram of a conventional photovoltaic thermal energy storage system and an energy storage system with independent power supply provided for embodiments of this application;

[0095] Figure 5 A circuit block diagram of the power supply system for the photovoltaic thermal energy storage system provided in the embodiments of this application;

[0096] Figure 6 A power system block diagram provided for an embodiment of this application;

[0097] Figure 7 A block diagram of the control module provided in the embodiments of this application;

[0098] Figure 8 A schematic diagram of the power supply device for the photovoltaic thermal energy storage system provided in the embodiments of this application;

[0099] Figure 9 This is a schematic diagram of the hardware structure of the electronic device provided in the embodiments of this application.

[0100] The accompanying drawings illustrate specific embodiments of this application, which will be described in more detail below. These drawings and descriptions are not intended to limit the scope of the concept in any way, but rather to illustrate the concept of this application to those skilled in the art through reference to particular embodiments. Detailed Implementation

[0101] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numbers in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this application. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this application as detailed in the appended claims.

[0102] It should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for analysis, data stored, data displayed, etc.) involved in this application are all information and data authorized by the user or fully authorized by all parties. Furthermore, the collection, use and processing of the relevant data must comply with relevant laws, regulations and standards, and corresponding operation entry points are provided for users to choose to authorize or refuse.

[0103] In the embodiments of this application, the terms "first" and "second" are used to distinguish identical or similar items with substantially the same function and effect. Those skilled in the art will understand that the terms "first" and "second" do not limit the quantity or execution order, and that "first" and "second" do not necessarily imply difference. It should be noted that in the embodiments of this application, words such as "exemplary" or "for example" are used to indicate examples, illustrations, or explanations. Any embodiment or design scheme described as "exemplary" or "for example" in this application should not be construed as being more preferred or advantageous than other embodiments or design schemes. Specifically, the use of words such as "exemplary" or "for example" is intended to present the relevant concepts in a concrete manner. In the embodiments of this application, "at least one" refers to one or more, and "more than one" refers to two or more.

[0104] It should be noted that the phrase "at...time" in the embodiments of this application can refer to the instant at which a certain situation occurs, or to a period of time after the occurrence of a certain situation. The embodiments of this application do not specifically limit this. In addition, the power supply method, device, system, medium and product for a photovoltaic thermal energy storage system provided in the embodiments of this application are only examples. A power supply method, device, system, medium and product for a photovoltaic thermal energy storage system may also include more or fewer contents.

[0105] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numerals in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present invention. Rather, they are merely examples of apparatuses and methods consistent with some aspects of the invention as detailed in the appended claims.

[0106] The technical solution of the present invention will be described in detail below with reference to specific embodiments. These specific embodiments can be combined with each other, and the same or similar concepts or processes may not be described again in some embodiments. The embodiments of the present invention will now be described with reference to the accompanying drawings.

[0107] To clearly understand the technical solution of this application, the existing technical solutions will first be described in detail. With the increasing volatility of the power grid and the growing demands of users for energy comfort and emergency power supply capabilities, the power supply capacity of photovoltaic thermal energy storage systems has become an important foundation for coordinating energy supply and demand and supporting low-carbon development goals.

[0108] In existing technologies, solar thermal energy storage systems typically employ a power supply architecture where the power grid serves as the primary power source, and the energy storage system acts as an auxiliary backup power source. The alternating current (AC) output from the grid is converted to direct current (DC), which is then combined with the DC output from the energy storage system and fed into the system's DC bus. The combined DC power supplies load equipment such as air conditioning compressors and fans to ensure the continuous and stable operation of the solar thermal energy storage system. However, existing technologies rely excessively on the amount of energy stored and the inertia of capacitors when dealing with fluctuations in multi-source power supply, sudden load changes, or extreme operating conditions. This makes it difficult to maintain stable power output when energy storage resources are insufficient or buffering capacity is reduced, easily leading to power quality degradation or even power outages. Therefore, existing technologies suffer from low power supply reliability in solar thermal energy storage systems.

[0109] Therefore, addressing the low power supply reliability of existing photovoltaic-thermal energy storage systems, this research found that a multi-energy-side collaborative compensation mechanism can be constructed to solve this problem. When the support capacity of a single energy source is insufficient, the adjustment potential of other energy sources can be activated to maintain system power supply stability: ① The dynamic response capability of key buffer units that perform power collection and transient support functions in the system can be used as a detection object. By detecting the real-time ability of these units to suppress their own voltage fluctuations, when their dynamic support level declines and cannot be compensated by conventional energy resources, this can be used as a key criterion to trigger system operation mode adjustments, ensuring that the voltage stability of power collection nodes can be prioritized in scenarios of multi-source fluctuations or load changes. ② A collaborative interaction mechanism between the electrical and non-electrical energy domains can be established. When the reserve resources and dynamic support capacity of the electrical side are insufficient to cope with the system power shortage, the adjustment potential of other energy domains can be actively explored. By regulating energy conversion equipment or releasing cross-domain stored energy, it can be converted into electrical energy and injected into the common collection node. The collaborative output of multiple energy domains can replace the support of a single electrical domain, making up for the power supply capacity gap. ③ A progressive adjustment strategy can be constructed from conventional power supply on the electrical side to compensation power supply across the energy side. It prioritizes the conventional combination of energy storage and multi-source power to maintain power supply. When the state of charge of energy storage and the inertia capability of key buffer units are detected to drop to the critical value, it automatically switches to the second level, activates and adjusts the adjustable resources on the thermal side, and generates compensation power to inject into the bus, forming a multi-level protection mechanism to avoid power outages.

[0110] Specifically, the state of charge of the energy storage system and the inertia output capability of the key buffer unit of the common bus can be detected. When the inertia support level of the buffer unit and the energy storage reserve drop to the critical value at the same time, the adjustable potential of the thermal side is actively activated. Based on the energy state of the heat medium, the heat storage level and the heat demand, a compensation command is generated to inject the electrical energy released or converted by the thermal side into the buffer unit of the common bus. The coordinated output across the energy side makes up for the lack of dynamic response capability of the electrical side, maintains the stability of the bus voltage and ensures the continuous and reliable power supply of the system under multi-source fluctuations and extreme operating conditions.

[0111] This application discloses a power supply method, apparatus, system, medium, and product for a photovoltaic thermal energy storage system. By acquiring the state of charge of the energy storage system and the output capacity of the shared bus capacitor inertia, when the energy storage capacity is sufficient and the bus inertia support capacity is normal, the system is powered by multiple sources of electrical energy. However, under extreme conditions where the energy storage capacity is insufficient and the shared bus capacitor inertia support capacity decreases, the system no longer relies solely on electrical side resources. Instead, it combines the temperature of the heat transfer medium, the thermal storage state, and the heat demand on the thermal side to adjust the operation of the thermal side and output compensating electrical energy. The multi-source electrical energy and the thermal side compensating electrical energy are jointly injected into the shared bus capacitor, making up for the power supply gap caused by insufficient energy storage resources and decreased capacitor buffer capacity. This improves the power supply reliability and power quality of the photovoltaic thermal energy storage system under multi-source fluctuations, load changes, and extreme conditions, avoiding problems such as power quality degradation and power outages.

[0112] Based on the above-mentioned inventive discovery, the technical solution of this application is proposed.

[0113] The following describes the application scenarios of the power supply method for the photovoltaic thermal energy storage system provided in the embodiments of the present invention. Figure 1 This is a schematic diagram illustrating an application scenario of the power supply method for the photovoltaic thermal energy storage system provided in this application embodiment. For example... Figure 1 As shown, this application scenario includes multiple power sources 101, a shared bus capacitor 102, a solar thermal energy storage system 103, and a control module 104. The control module 104 acquires various electrical energy outputs from the multiple power sources 101, the state of charge of the energy storage system, and the inertia output capability of the shared bus capacitor 102. When the state of charge is higher than or equal to a preset state threshold and the inertia output capability is higher than or equal to a preset capability threshold, the control module 104 injects various electrical energy sources into the shared bus capacitor 102 and transmits the energy through the shared bus capacitor 103. 02 supplies power to the solar thermal energy storage system 103. When the state of charge is lower than the preset state threshold and the inertia output capability is lower than the preset capability threshold, the control module 104 obtains the heat medium temperature of the solar thermal energy storage system 103, the heat storage status of the preset heat storage device, and the heat demand of the preset heat load. Based on the heat medium temperature, heat storage status, and heat demand, the control module 104 generates an inertia compensation command. The control module 104 injects various types of electrical energy and compensation electrical energy into the shared bus capacitor 102 and supplies power to the solar thermal energy storage system 103 through the shared bus capacitor 102.

[0114] The embodiments of the present invention will now be described with reference to the accompanying drawings.

[0115] Figure 2 A flowchart illustrating the power supply method for the photovoltaic thermal energy storage system provided in this application embodiment. Figure 1 .like Figure 2 As shown, in this embodiment, the execution entity of this invention is the control module. Therefore, the power supply method for the photovoltaic thermal energy storage system provided in this embodiment includes the following steps:

[0116] S201. Obtain the state of charge of multiple electrical energy and energy storage systems from multiple power sources and the inertia output capability of the shared bus capacitor; wherein, the inertia output capability is used to represent the ability of the shared bus capacitor to suppress voltage fluctuations across the shared bus capacitor.

[0117] Specifically, voltage and current sensors can be deployed on the electrical side of the photovoltaic-thermal storage system to collect real-time voltage and current signals from the photovoltaic array, the power grid, and the energy storage system. The analog signals are converted into digital quantities by the controller's built-in analog-to-digital converter, and real-time power values ​​for various electrical energy sources are calculated based on the product of voltage and current. Simultaneously, the battery management system of the energy storage system directly reads its state of charge percentage. By setting voltage detection circuits across the shared bus capacitor, voltage fluctuation data across the capacitor is collected in real time. The controller calculates the capacitor's inertia output capacity based on the rate of voltage change per unit time. This step provides the controller with basic data to determine the current operating status of the system and whether thermal resources need to be activated to assist in power supply.

[0118] State of charge (SCC) refers to the ratio of the remaining charge in an energy storage system to its total charge when fully charged. It is usually expressed as a percentage and is used to visually reflect how much energy the energy storage system can still provide, so that the controller can determine whether it needs to supply power to the load or charge from other sources. For example, if an energy storage battery pack has a total capacity of 100 kWh and currently has 60 kWh remaining, then its SCC is 60%.

[0119] Inertia output capability refers to the ability of a shared bus capacitor to suppress the rate of voltage change and maintain voltage stability when the system voltage fluctuates. It measures the strength of a capacitor's ability to provide instantaneous power support during sudden changes in the power grid or load, and its value is usually related to the capacitor's capacitance and voltage change rate. For example, when an air conditioner compressor suddenly starts, causing a momentary drop in bus voltage, a capacitor with strong inertia output capability can quickly release electrical energy, suppressing the voltage drop from 10% to less than 2%.

[0120] S202. When the state of charge is higher than or equal to the preset state threshold and the inertia output capability is higher than or equal to the preset capability threshold, multiple types of electrical energy are injected into the shared bus capacitor, and the shared bus capacitor supplies power to the photovoltaic thermal energy storage system; wherein, the shared bus capacitor is electrically connected to multiple power sources.

[0121] Specifically, controllable switch modules can be installed between each power source and the shared bus capacitor. When the state of charge of the energy storage system is detected to be higher than or equal to a preset state threshold, and the inertia output capability of the shared bus capacitor is detected to be higher than or equal to a preset capability threshold, all controllable switch modules are closed, allowing the electrical energy output from each power source to smoothly flow into the shared bus capacitor. At the same time, the power supply switch between the shared bus capacitor and the load of the solar thermal energy storage system is closed, allowing the shared bus capacitor to stably output the collected electrical energy to load equipment such as air conditioning compressors and fans, providing the electrical energy required for the operation of various components of the solar thermal energy storage system. This step is used to achieve effective aggregation and stable supply of multi-source electrical energy under the condition of sufficient energy storage and normal bus inertia support, making full use of the electrical energy of each power source, ensuring the continuous normal operation of the solar thermal energy storage system, and giving full play to the synergistic effect of each power source.

[0122] For example, suppose in an integrated photovoltaic-thermal energy storage building, the control module reads that the state of charge (SOC) of the energy storage battery is 85%, and simultaneously detects that the voltage fluctuation rate of the shared bus capacitor is extremely low and the inertia output capability is sufficient. The control module's internal preset SOC threshold is 30%, and the capability threshold is 50%, both of which are significantly higher than these thresholds. The control module immediately sends a conduction signal simultaneously to the photovoltaic inverter, the grid interface converter, and the bidirectional energy storage converter, causing the DC power generated by the photovoltaic array, the rectified DC power from the grid, and the DC power released by the energy storage battery to all converge and be injected into the shared bus capacitor. This capacitor stabilizes and filters the mixed energy, and then, via the frequency converter, continuously supplies power to the air conditioning compressor and fan, ensuring the stable and efficient operation of the entire photovoltaic-thermal energy storage system during this period.

[0123] S203. When the state of charge is lower than the preset state threshold and the inertia output capability is lower than the preset capability threshold, the heat medium temperature of the photovoltaic thermal energy storage system, the heat storage status of the preset thermal energy storage device, and the heat demand of the preset heat load are obtained, and an inertia compensation command is generated based on the heat medium temperature, the heat storage status, and the heat demand; wherein, the inertia compensation command is used to adjust the operating status of the preset thermal side in the photovoltaic thermal energy storage system to provide compensation power for the shared bus capacitor.

[0124] Specifically, temperature sensors can be installed on the heat medium pipelines of the solar thermal energy storage system to collect temperature data in real time during the flow of the heat medium and obtain the heat medium temperature. Liquid level sensors and temperature sensors can be embedded inside the pre-set heat storage device to collect the liquid level and temperature data of the heat storage medium. Combined with the rated volume of the heat storage device, the heat storage state of the pre-set heat storage device can be obtained. Flow sensors and temperature sensors can be installed on the inlet and outlet water pipelines of the pre-set heat load to collect the inlet water flow rate, inlet water temperature, and return water temperature of the heat load. Combined with the rated heat consumption parameters of the heat load, the heat demand of the pre-set heat load can be obtained. The acquired data on heat medium temperature, heat storage state, and heat demand are then transmitted to the system control system. The control module has built-in preset parameter matching rules. When the heat medium temperature is higher than the set value, the heat storage state is sufficient, and the heat demand is lower than the set value, it generates inertia compensation commands to control the start and stop of the preset heat exchanger on the heat side and adjust the heat exchange power. When the heat medium temperature is too low, the heat storage state is insufficient, or the heat demand is too high, it generates inertia compensation commands to control the start of the auxiliary heating device on the heat side and adjust the heat medium circulation speed. This step is used to obtain the key operating parameters of the heat side, and combine these parameters to generate inertia compensation commands adapted to the current operating conditions. This provides an operational basis for the subsequent release or conversion of compensation electrical energy on the heat side, ensuring that the compensation electrical energy can accurately match the needs of the shared bus capacitor.

[0125] For example, the control module of a solar thermal energy storage system detects that the state of charge of the energy storage battery has dropped to 15%, below the preset 30% threshold. Simultaneously, it detects that the voltage of the shared bus capacitor fluctuates drastically during load switching, and the calculated inertia output capability is only 20%, also below the preset 50% capability threshold. At this time, the control module reads the current temperature of the heat transfer medium pipeline as 45°C through a temperature sensor, obtains the current thermal storage state as "high heat capacity" (e.g., heat storage reaches 80%) from the thermal storage tank monitoring system, and obtains the preset heat load demand as "low heating demand" from the building automation system. The control module analyzes these data and concludes that the heat transfer medium temperature is moderate, the thermal storage device has sufficient heat, but the external heat demand is low, indicating conditions for transferring some energy from the thermal side. Therefore, the control module issues an inertia compensation command to the heat pump unit and the electric regulating valve, stating that "reduce the heat pump's power output to the thermal storage tank, and prioritize the transfer of the saved electrical energy to the shared bus capacitor." This step is used to generate specific control signals to initiate the power compensation process when the electrical power supply capacity is severely insufficient, by tapping the energy regulation potential on the thermal side.

[0126] Among them, the preset state threshold refers to the minimum allowable value of the state of charge of the energy storage system, and the preset capacity threshold refers to the minimum allowable value of the shared bus capacitor inertia output capacity. These two thresholds can be determined by engineers during the commissioning phase of the solar-thermal energy storage system based on the system's historical operating data and load characteristics. In practice, the minimum state of charge value and the minimum inertia output capacity value that the system can maintain stable power supply under various operating conditions are first recorded. Then, the median value or a value slightly higher than the minimum value is taken as the preset threshold and written into the controller as the basis for subsequent judgments.

[0127] Inertia compensation command refers to the adjustment signal sent by the controller to the thermal side equipment in the solar-thermal energy storage system when the energy storage system's power is insufficient and the inertia support capacity of the shared bus capacitor decreases. This signal alters the operating state of the thermal side, causing it to release or convert additional electrical energy to compensate for the power supply gap on the electrical side. It is used to maintain stable system operation by activating the energy on the thermal side when electrical resources are insufficient. For example, when the controller determines that the energy storage battery has only 10% charge remaining and the bus voltage fluctuates drastically, it immediately sends an inertia compensation command to the heat pump unit, requiring it to temporarily reduce its heat output power and prioritize injecting the saved electrical energy into the shared bus capacitor to support the operation of critical loads such as the compressor.

[0128] Compensation energy refers to the electrical energy released or converted by the thermal side equipment in a solar thermal energy storage system after responding to an inertia compensation command, and injected into the shared bus capacitor when the energy storage system's power is insufficient and the inertia support capacity of the shared bus capacitor decreases. This energy is used to compensate for the insufficient power supply capacity on the electrical side and maintain the stable operation of the system. For example, when the energy storage battery is depleted and the bus voltage fluctuates drastically, the heat pump unit, after receiving the inertia compensation command, temporarily transfers some of the electrical energy originally used to heat the heat transfer medium. This transferred electrical energy is the compensation energy, which is sent to the shared bus capacitor to support the emergency operation of the air conditioning compressor.

[0129] Both the pre-set thermal storage device and the pre-set heat load are components of the pre-set thermal side. After generating heat energy, the solar thermal storage system transfers the heat energy to the pre-set thermal storage device (such as a hot water storage tank) for storage. It can also be directly supplied to the pre-set heat load (such as underfloor heating coils) for consumption. The thermal side encompasses all equipment and piping from heat generation and storage to consumption, including heat pumps, thermal storage tanks, heat exchangers, circulating pumps, and terminal heat dissipation equipment. In terms of connections, the heat source equipment of the solar thermal storage system can be connected to the inlet of the heat exchanger of the pre-set thermal storage device via insulated pipes. The outlet of the pre-set thermal storage device is then connected to the water supply pipeline of the pre-set heat load via a circulating pump and an electric regulating valve. The power cables for all thermal side equipment are uniformly connected to the shared bus capacitor of the solar thermal storage system, forming a complete chain of electrical side power supply – thermal side heat generation – thermal storage device heat storage – heat load heat consumption. For example, in an industrial park, the heat pump unit of the solar thermal energy storage system first sends the hot water it produces into an underground thermal storage tank for storage. The thermal storage tank then transmits the hot water to the air conditioning units of each building through a secondary pipeline network for heating. The auxiliary electric heaters of the heat pump and thermal storage tank, as well as the fans of the air conditioning units, are all powered by the bus capacitor of the solar thermal energy storage system.

[0130] S204. Inject various types of electrical energy and compensation electrical energy into the shared bus capacitor, and supply power to the photovoltaic thermal energy storage system through the shared bus capacitor; wherein, compensation electrical energy refers to the electrical energy released or converted by the preset thermal side after the inertia compensation command is executed, and the shared bus capacitor is electrically connected to the preset thermal side.

[0131] Specifically, controllable switch modules and power conversion modules can be installed between each power source and the shared bus capacitor, and between the preset thermal side and the shared bus capacitor. The controllable switch modules control the on / off state of the power transmission path, while the power conversion modules convert different types of electrical energy output from each power source, as well as compensation energy released or converted by the preset thermal side, into DC power compatible with the shared bus capacitor. Controlling the closure of all controllable switch modules allows the converted electrical energy and compensation energy to simultaneously flow into the shared bus capacitor. Simultaneously, it controls the closure of the power supply switches between the shared bus capacitor and each load of the solar thermal energy storage system. The shared bus capacitor buffers and stabilizes the incoming electrical energy before continuously outputting it to load devices such as air conditioning compressors and fans, powering the solar thermal energy storage system. This step effectively aggregates and stably outputs multi-source electrical energy and thermal side compensation energy under conditions of insufficient energy storage and decreased inertia support capacity of the shared bus capacitor, ensuring uninterrupted power supply to the solar thermal energy storage system.

[0132] For example, after the control module issues an inertia compensation command, the heat pump unit immediately reduces its heat output to the thermal storage tank, saving some of the electrical energy originally used to drive the heat pump compressor. Simultaneously, the electric regulating valve converts some of the heat energy stored in the heat transfer medium pipeline into electrical energy via a thermoelectric converter. These two sources of electrical energy together constitute the compensation energy, which is then injected into the shared bus capacitor after being converted by the power electronic interface. Meanwhile, the remaining electrical energy from the photovoltaic array, the power grid, and the energy storage system also continuously flows into this capacitor. This multi-source electrical energy is collected and stabilized in the shared bus capacitor, and then used by the inverter to power critical loads such as the air conditioning compressor and fan, ensuring that the photovoltaic-thermal storage system can maintain continuous and stable operation even under extreme conditions of insufficient energy storage and decreased bus capacitor inertia.

[0133] The power supply method of photovoltaic-thermal energy storage (PV-TES) systems can be applied to the integrated PV-TES design of commercial complexes in the building energy sector. During peak summer electricity consumption periods, PV power generation fluctuates significantly due to cloudy weather, while frequent start-stop cycles of multiple air conditioning compressors cause sudden load changes. Meanwhile, the energy storage battery capacity is already low due to previous use, and the inertia support capacity of the shared bus capacitor is reduced by repeated voltage surges. This method, by real-time monitoring of energy storage status and bus capacitor inertia, immediately acquires the heat medium temperature, heat storage capacity of the thermal storage tank, and end-user heat demand when electrical resources are insufficient. It generates inertia compensation commands to adjust the operation of the heat pump unit, injecting the compensated electrical energy saved or converted from the thermal side, along with the remaining electrical energy from PV, the grid, and energy storage, into the bus capacitor, thereby maintaining a stable power supply to the air conditioning system. Under the dual challenges of insufficient energy storage capacity and reduced bus capacitor inertia buffering capacity, this method avoids power quality degradation or even power outages caused by fluctuations in multi-source power supply and sudden load changes, thus improving the power supply reliability of the PV-TES system.

[0134] This embodiment provides a power supply method for a photovoltaic thermal energy storage system. By acquiring the state of charge of the energy storage system and the output capacity of the shared bus capacitor inertia, when the energy storage capacity is sufficient and the bus inertia support capacity is normal, the system is powered by multiple sources of electricity. However, under extreme conditions where the energy storage capacity is insufficient and the shared bus capacitor inertia support capacity decreases, the system no longer relies solely on electrical side resources. Instead, it combines the temperature of the heat transfer medium, the thermal storage state, and the heat demand on the thermal side to adjust the operation of the thermal side and output compensating electricity. The multi-source electricity and the thermal side compensating electricity are jointly injected into the shared bus capacitor, making up for the power supply gap caused by insufficient energy storage resources and decreased capacitor buffer capacity. This improves the power supply reliability and power quality of the photovoltaic thermal energy storage system under multi-source fluctuations, load changes, and extreme conditions, avoiding problems such as power quality degradation and power outages.

[0135] In one possible design, multiple power sources, including a photovoltaic system, are used. In S202, various electrical energy sources are injected into a shared bus capacitor, which then powers the photovoltaic-thermal storage system, including:

[0136] S2021. Based on the state of charge, inertia output capability, and real-time load power of the solar thermal energy storage system, establish a dynamic power allocation model on the power side; wherein, the dynamic power allocation model on the power side is used to determine the injection priority and power ratio of multiple power sources injecting power into the shared bus capacitor.

[0137] Specifically, three data storage areas can be first designated in the control module's memory. These areas are used to receive and update the state of charge (SOC) values ​​of the energy storage system, the inertia output capability values ​​of the shared bus capacitor, and the real-time load power values ​​from the load power detection unit. These three values ​​constitute the model's input parameter set. Then, the logic operation unit in the control module processes the input parameter set: the logic operation unit compares the inertia output capability values ​​with preset rate thresholds stored internally. Based on the comparison results, it divides the system state into a "voltage stable range" or a "voltage fluctuation range." Simultaneously, it compares the SOC values ​​with preset state thresholds and the load power values ​​with rated power thresholds. Based on these three comparison results, the logic operation unit looks up the corresponding injection priority order and power ratio coefficient from an internally stored allocation rule table. This rule table is a two-dimensional lookup table pre-generated by fitting experimental data. The horizontal axis represents the system state range, and the vertical axis represents the combined range of SOC and load power. Each cell in the table stores a set of corresponding priority and ratio parameters. The logic operation unit outputs the found priority and ratio parameters into the model output register, forming a complete dynamic energy allocation model. This step is used to establish a mapping relationship that can automatically determine the primary and secondary power supply relationship and power allocation ratio between photovoltaic and energy storage based on the real-time status of the system.

[0138] For example, when establishing a dynamic power allocation model on the power side, the control module of a solar thermal energy storage system first reads the current state of charge (60%) from the energy storage battery management system, the inertia output capability (80%) calculated from the shared bus capacitor voltage detection unit, and the real-time load power (45kW) obtained from the load power detection unit. The control module sends these three values ​​as input parameters to the internally constructed model calculation unit. This model consists of a state judgment layer and an allocation strategy layer: the state judgment layer first compares the inertia output capability (80%) with a preset 50% rate threshold to determine that the system is currently in "voltage stable mode," then compares the state of charge (60%) with a preset 30% state threshold to conclude that "energy storage is sufficient," and finally compares the load power (45kW) with the system's rated power (60kW) to conclude that "load is moderate." The state judgment layer passes these intermediate results to the allocation strategy layer. The allocation strategy layer uses "voltage stable mode + sufficient energy storage + moderate load" as a combined index to find the corresponding injection priority of "PV priority, energy storage backup" and the power ratio of "PV power supply 75%, energy storage standby 25%" in the internally stored allocation rule table. The control module stores these priority and ratio parameters in the model output register, thus completing the establishment of the dynamic power allocation model on the power side.

[0139] The dynamic power allocation model is a pre-built logic framework within the control module. It takes the state of charge (SOC) of the energy storage system, the inertia output capability of the shared bus capacitor, and the real-time load power of the photovoltaic-thermal storage system as input parameters. After internal state judgment and rule matching, it outputs a set of decision information including the priority order of energy injection from the photovoltaic and energy storage systems to the bus capacitor, as well as the power ratio coefficient. This information is used to dynamically adjust the multi-source power supply strategy based on the real-time operating status of the system, ensuring efficient and stable power allocation under different operating conditions. For example, if the model receives the following input parameters at a certain moment: energy storage SOC 80%, inertia output capability 70%, and real-time load power 50kW, the internal logic unit determines that the system is in a "stable voltage and sufficient energy storage" state. Then, it matches and outputs the priority order of "photovoltaic priority, energy storage backup" and the power ratio coefficient of "photovoltaic power supply 80%, energy storage on standby" from the rule table.

[0140] S2022. Based on the dynamic power allocation model, generate power allocation instructions. These instructions are used to prioritize injecting the power output from the photovoltaic system into the shared bus capacitor when the voltage fluctuation rate of the shared bus capacitor is lower than a preset rate threshold, and to configure the energy storage system in a fast-response standby state so that the energy storage system immediately discharges when the voltage fluctuation rate of the shared bus capacitor increases. The instructions also prioritize injecting the power output from the energy storage system into the shared bus capacitor when the voltage fluctuation rate of the shared bus capacitor is higher than a preset rate threshold, and to configure the photovoltaic system in a continuous power supply standby state so that the photovoltaic system continuously injects power when the voltage fluctuation rate of the shared bus capacitor decreases.

[0141] Specifically, the control module can read the voltage detection data across the shared bus capacitor in real time, calculate the current voltage fluctuation rate, and input this rate as a query index into the established dynamic power allocation model. Based on the comparison between this rate and a preset rate threshold, the model outputs the corresponding injection priority order and power ratio parameters from its internally stored allocation rule table. When the voltage fluctuation rate is lower than the preset rate threshold, the model outputs a priority order of "PV priority, energy storage backup," and the power ratio parameter is full power supply from the PV system. Based on this output, the control module generates a first-type power allocation command, sends it to the PV inverter to set it to main supply mode and inject maximum power into the bus capacitor, and simultaneously sends it to the energy storage bidirectional converter to configure it to a fast-response backup state, placing its power switches in standby trigger mode. Once the voltage fluctuation rate is detected to exceed the threshold, it can automatically switch to discharge within milliseconds. When the voltage fluctuation rate is higher than the preset rate threshold, the model outputs a priority order of "energy storage priority, PV backup," and the power ratio parameter is maximum available power discharge from the energy storage system. Based on this output, the control module generates a second type of power-side allocation command, which is sent to the bidirectional energy storage converter to immediately discharge to the bus capacitor at rated power. Simultaneously, it is sent to the photovoltaic inverter to configure it into a continuous power supply standby state, maintaining grid connection but temporarily suspending full-power injection, and only maintaining basic output in preparation for resuming power supply after voltage stabilization. This step transforms the strategy output from the dynamic power-side allocation model into executable control signals, enabling the photovoltaic and energy storage systems to switch primary and secondary power supply roles in real time according to bus voltage fluctuations. This ensures that during voltage fluctuations, the faster-responding energy storage system undertakes the voltage stabilization task, while photovoltaic power is prioritized when the voltage is stable.

[0142] For example, the control module reads the voltage detection data across the shared bus capacitor in real time and calculates that the current voltage fluctuation rate is 2 volts per second, which is lower than the preset threshold of 5 volts per second. Based on the allocation strategy corresponding to this input and output, which is "PV priority, energy storage backup", the control module generates a first type of power allocation command and sends it to the PV inverter and the energy storage bidirectional converter: instructing the PV inverter to operate in maximum power search mode, injecting all the power output from the PV array into the shared bus capacitor, and simultaneously instructing the energy storage bidirectional converter to enter a fast response backup state, configuring its internal power switches to standby trigger mode, so that it can automatically switch to discharge within milliseconds once the voltage fluctuation rate exceeds the threshold of 5 volts per second. Subsequently, when a high-power wind turbine suddenly starts up, causing the bus voltage fluctuation rate to rise instantaneously to 8 volts per second, the control module immediately generates a second type of power distribution command based on the model output. The command instructs the bidirectional energy storage converter to immediately discharge to the bus capacitor at a rated power of 30 kilowatts. At the same time, the command instructs the photovoltaic inverter to switch to continuous power supply standby mode, keeping the inverter connected to the grid but temporarily suspending full power injection, maintaining only the basic output of 5 kilowatts. Full photovoltaic power supply will be restored after the voltage fluctuation rate drops back to 3 volts per second.

[0143] S2023. According to the power allocation instructions, inject various types of power into the shared bus capacitor in batches according to injection priority and power distribution.

[0144] Specifically, the control module can send the generated power distribution instructions to both the photovoltaic inverter and the energy storage bidirectional converter. These instructions contain explicit priority sequences and power ratio parameters. Upon receiving the instructions, the photovoltaic inverter adjusts the duty cycle of the power switches in its internal maximum power point search circuit according to the set photovoltaic injection priority and power value. This ensures that the DC power output from the photovoltaic array is injected into the shared bus capacitor in batches and continuously at specified current and voltage values. Simultaneously, the energy storage bidirectional converter configures its internal power switches to standby mode according to the energy storage priority and standby requirements set in the instructions. When the bus voltage fluctuation rate exceeds a threshold, it immediately starts discharging according to the preset power ratio in the instructions, injecting the energy from the energy storage battery into the bus capacitor in batches at calculated power values. The two power sources converge into the capacitor in batches according to the order and proportion specified in the instructions, and after mixing and voltage stabilization within the capacitor, they are supplied to the load. This step ensures that the photovoltaic and energy storage power sources deliver power to the bus capacitor in an orderly manner according to the primary and secondary relationships and power distribution scheme set by the control module.

[0145] For example, the control module sends the generated power distribution instructions to both the photovoltaic inverter and the energy storage bidirectional converter. The injection priority set in the instructions is "PV priority, energy storage backup," with a power ratio of 75% for the photovoltaic system and 25% for the energy storage system in standby mode. Upon receiving the instructions, the photovoltaic inverter adjusts the duty cycle of the power switches in its internal maximum power point search circuit according to the set photovoltaic injection priority and 75% power ratio, allowing 30kW (75%) of the currently available 40kW of power from the photovoltaic array to be injected into the shared bus capacitor in batches and continuously. Simultaneously, the energy storage bidirectional converter, according to the energy storage backup state and 25% power ratio requirement set in the instructions, configures its internal power switches to standby mode, without actually discharging, but ready to immediately supplement 10kW of power at a 25% ratio upon detecting bus voltage fluctuations. The two power sources converge into the capacitor in batches according to the order and ratio specified in the instructions, and after mixing and voltage stabilization within the capacitor, they are supplied to the load.

[0146] The injection priority determines which power source's energy is used first. For example, when the voltage is stable, photovoltaic power is used first. The power distribution ratio determines the specific numerical allocation of the output power of each power source when supplying power simultaneously. For example, it may stipulate that the photovoltaic system undertakes 70% of the total power supply and the energy storage system undertakes 30%, which is used to achieve orderly and reasonable power distribution when supplying power from multiple sources, avoiding disorderly competition or power imbalance between power sources. For example, when there is sufficient sunlight at noon and the bus voltage is stable, the injection priority set by the control module is photovoltaic first and energy storage as backup, and the power distribution ratio is that the photovoltaic system outputs 35kW and the energy storage system is in standby mode outputting 0kW. When clouds pass by and the photovoltaic output drops to 20kW, the control module adjusts the power distribution ratio so that the photovoltaic system outputs 20kW and the energy storage system immediately supplements the output with 15kW, so that both can meet the 50kW load demand.

[0147] The technical effect of this solution in this embodiment is as follows: By combining the state of charge of the energy storage system, the output capability of the shared bus capacitor inertia, and the real-time load power of the system to construct a dynamic power allocation model on the power side, the power supply priority and power ratio of the photovoltaic system and the energy storage system are flexibly switched according to the bus voltage fluctuation rate. When the voltage fluctuation is small, photovoltaic power is used first and the energy storage is set as a fast response backup, making full use of clean energy and maintaining the system's responsiveness. When the voltage fluctuation is fast, energy storage power is put into priority to quickly smooth out disturbances and stabilize the bus voltage. This achieves refined, adaptive, and coordinated adjustment of multiple power sources, improves power supply stability and energy utilization, and solves the problems of unreasonable multi-source power coordinated adjustment and untimely response to voltage fluctuations.

[0148] In one possible design, S2023 injects various types of electrical energy into the shared bus capacitor in batches according to injection priority and power allocation based on the power distribution instructions from the power side, including:

[0149] S20231. Obtain the real-time voltage value and voltage change trend of the shared bus capacitor, and construct a waveform shaping model based on the real-time voltage value and voltage change trend; wherein, the waveform shaping model is used to match the time-varying law of the injected power of various electrical energies with the voltage fluctuation phase of the shared bus capacitor.

[0150] Specifically, a voltage sensor can be connected in parallel across the shared bus capacitor. This sensor continuously collects the instantaneous voltage value across the capacitor at a sampling frequency of thousands of times per second, and sends the collected analog voltage signal to the analog-to-digital converter unit of the control module, converting it into digital real-time voltage value and voltage change trend data. The control module constructs a waveform shaping model based on this data. This model consists of two components connected in series: a phase detection layer and a function mapping layer. The real-time voltage value and voltage change trend first enter the phase detection layer. This layer calculates the voltage change rate by differentiating the voltage value and divides the voltage fluctuation process into rising and falling phases based on the sign of the voltage change rate. It also records the voltage value sequence corresponding to each phase. Subsequently, these phase markers and voltage sequences are sent to the function mapping layer. This layer generates a mapping function for the rising phase where the power decreases as the voltage increases, and a mapping function for the falling phase where the power increases as the voltage decreases. These two functions are then combined into a complete waveform shaping model. This step is used to establish a mathematical mapping relationship that can automatically adjust the injected power change pattern according to the phase fluctuation of the bus capacitor voltage, providing a model basis for the subsequent generation of waveform shaping injection commands.

[0151] For example, the control module continuously collects the instantaneous voltage values ​​of the capacitor at a sampling frequency of thousands of times per second using voltage sensors connected in parallel across the shared bus capacitor, and converts these analog signals into a digital real-time voltage data sequence. The control module performs differential calculations on these voltage data to obtain the voltage trend: the current voltage is 652V and is rising, with a positive rate of change. Based on this data, the control module constructs a waveform shaping model, which consists of a phase detection layer and a function mapping layer. The phase detection layer divides the voltage fluctuation process into rising and falling phases based on the sign of the rate of change, and records that the current voltage is in the rising phase, with the voltage value gradually increasing from 650V to 655V. Subsequently, the function mapping layer, according to preset waveform shaping rules, generates a mapping relationship for the current rising phase where the power gradually decreases as the voltage increases; that is, the lower the voltage, the greater the injected power, and the higher the voltage, the smaller the injected power. Simultaneously, it generates a mapping relationship for the falling phase where the power gradually increases as the voltage decreases; that is, the higher the voltage, the smaller the injected power, and the lower the voltage, the greater the injected power. This step is used to establish a mathematical mapping relationship that can automatically adjust the injected power change pattern according to the phase fluctuation of the bus capacitor voltage, providing a model basis for the subsequent generation of waveform shaping injection commands.

[0152] S20232. Generate waveform shaping injection instructions based on various power and waveform shaping models; wherein, the waveform shaping injection instructions are used to make the injected power decrease as the voltage rises when the voltage of the shared bus capacitor is in the rising phase, and to make the injected power increase as the voltage falls when the voltage of the shared bus capacitor is in the falling phase.

[0153] Specifically, the control module inputs the real-time detected shared bus capacitor voltage value into the constructed waveform shaping model. The model calls the corresponding mapping function based on the current voltage stage. When the voltage is rising, the model outputs a sequence of instantaneous power target values ​​that decreases as the voltage increases; when the voltage is falling, the model outputs a sequence of instantaneous power target values ​​that increases as the voltage decreases. The control module compares these instantaneous power target value sequences with the available total electrical energy to calculate the real-time power values ​​required by the photovoltaic system and the energy storage system, and converts the time-varying power values ​​into pulse width modulation signals or digital communication commands to generate waveform shaping injection commands, which are then sent to the photovoltaic inverter and the bidirectional energy storage converter. This step converts the power variation pattern output by the waveform shaping model into an executable control signal, enabling the injected electrical power into the bus capacitor to adjust in the opposite direction to the voltage fluctuation phase, thereby suppressing voltage fluctuations.

[0154] For example, the control module inputs the currently detected shared bus capacitor voltage of 652V (in the rising phase) into the constructed waveform shaping model. The model calls the corresponding decreasing mapping function based on the current voltage rising phase to calculate the instantaneous power target value required at the current voltage point as 35kW, and predicts that the power target value will decrease to 30kW when the voltage continues to rise to 655V. The control module compares these instantaneous power target value sequences with the total available power of various energy sources. At this point, the available power of the photovoltaic system is 40kW, and the available power of the energy storage system is 20kW, with a total available power of 60kW, which is greater than the required maximum injection power. Based on the "photovoltaic priority, energy storage backup" priority and power ratio set in the power-side dynamic allocation model, the control module calculates that under the current demand of 35kW, the photovoltaic system should output 30kW and the energy storage system should output 5kW, and generates the corresponding pulse width modulation signal sequence as a waveform shaping injection command. The directive explicitly states that during the 5-millisecond period when the voltage rises from 652V to 655V, the output power of the photovoltaic inverter should gradually decrease from 30kW to 28kW, and the output power of the energy storage bidirectional converter should gradually decrease from 5kW to 2kW. This step is used to convert the power change pattern output by the waveform shaping model into an executable control signal, enabling the power injected into the bus capacitor to be adjusted in the opposite direction to the voltage fluctuation phase.

[0155] S20233. According to the waveform shaping injection command, various electrical energies are injected into the shared bus capacitor in batches according to the injection priority and power ratio, following a decreasing or increasing trend.

[0156] Specifically, after receiving the waveform shaping injection command from the control module, the photovoltaic inverter and the bidirectional energy storage converter receive a time-varying instantaneous power target value sequence, along with corresponding injection priority and power ratio parameters. Based on the priority and power ratio set in the command, the photovoltaic inverter extracts the required output power value from its internal maximum power point search circuit and adjusts the duty cycle of the power switches, causing the electrical energy output from the photovoltaic array to be injected into the bus capacitor in batches according to an increasing or decreasing trend. Simultaneously, the bidirectional energy storage converter adjusts the conduction timing of the switches in its bidirectional conversion circuit in real time according to the power ratio and trend requirements set in the command, causing the electrical energy released by the energy storage battery to also be injected into the bus capacitor in batches according to the same increasing or decreasing trend. The two power sources synchronously adjust their output power according to the change pattern specified in the command; the injected power gradually decreases when the bus capacitor voltage rises and gradually increases when the voltage falls, thus creating power compensation within the capacitor that is out of phase with the voltage fluctuations. This step is used to enable the total power injected into the bus capacitor to be adjusted in the opposite direction to voltage fluctuations. By actively changing the waveform of the injected electrical energy, voltage fluctuations are suppressed, and the stability of the bus voltage is improved.

[0157] For example, when the photovoltaic inverter and the energy storage bidirectional converter receive a waveform shaping injection command from the control module, the command explicitly states that during the current voltage rise phase, the photovoltaic system prioritizes power supply with a power ratio of 85%, while the energy storage system provides supplementary power supply in standby mode with a power ratio of 15%. Both systems must output power in a decreasing trend as the voltage increases. Based on the decreasing trend requirement set in the command, the photovoltaic inverter adjusts the duty cycle of the power switches in its internal maximum power point search circuit in real time. This allows the photovoltaic array to inject power into the bus capacitor in batches, starting from the current 30kW, as the bus capacitor voltage gradually rises from 652V to 655V, decreasing by 0.4kW per millisecond. Simultaneously, based on the 15% power ratio and the same decreasing trend requirement set in the command, the energy storage bidirectional converter adjusts the switching sequence of the switches in its bidirectional conversion circuit in real time. This allows the energy released by the energy storage battery to be injected into the bus capacitor in batches, starting from the current 5.3kW, decreasing by 0.07kW per millisecond. The two power sources adjust their output power synchronously according to the change pattern specified in the instruction. When the voltage of the bus capacitor rises, the injected power gradually decreases, thereby forming a power compensation inside the capacitor that is opposite to the phase of the voltage fluctuation.

[0158] The technical effect of this scheme in this embodiment is as follows: based on the priority and allocation of energy injection in batches, further optimization of the injection waveform achieves zero disturbance to the bus voltage during the injection process. This method constructs a waveform shaping model based on the real-time voltage value and trend of the shared bus capacitor, ensuring that the change in injected power matches the phase of voltage fluctuations: during the voltage rise phase, the injected power decreases as the voltage increases to avoid exacerbating the voltage rise; during the voltage fall phase, the injected power increases as the voltage decreases to prevent accelerating the voltage fall. This waveform-shaping injection method prevents the energy injection process itself from causing additional voltage fluctuations. Simultaneously, by injecting less at peak values ​​and more at valley values, the injected current actively smooths the voltage waveform, solving the problem of secondary disturbance to the bus voltage during the energy injection process.

[0159] In one possible design, S204, various types of electrical energy and compensation energy are injected into a shared bus capacitor, and the shared bus capacitor supplies power to the photovoltaic thermal energy storage system, including:

[0160] S2041. Obtain the instantaneous phase characteristics and instantaneous amplitude characteristics of the real-time voltage waveform of the shared bus capacitor; wherein, the instantaneous phase characteristics are used to represent the phase angle of the real-time voltage waveform at the current moment, and the instantaneous amplitude characteristics are used to represent the amplitude of the real-time voltage waveform at the current moment.

[0161] Specifically, a voltage sensor can be connected in parallel across the shared bus capacitor. This sensor continuously acquires the instantaneous voltage value across the capacitor at a sampling frequency of thousands of times per second, and sends the acquired analog voltage signal to the analog-to-digital converter (ADC) unit of the control module, converting it into digital real-time voltage waveform data. The control module inputs this real-time voltage waveform data into an internally integrated phase-locked loop (PLL) circuit. The PLL searches the input voltage waveform through closed-loop feedback control, extracting the instantaneous phase angle as the instantaneous phase feature. Simultaneously, the real-time voltage waveform data is input to an amplitude detection circuit. This circuit extracts the voltage amplitude as the instantaneous amplitude feature through peak hold and RMS calculations. This step is used to parse the phase and amplitude information of the voltage from the real-time voltage waveform of the bus capacitor, providing a phase reference and amplitude benchmark for the subsequent generation of an injection current orthogonal to the voltage waveform phase.

[0162] For example, the control module can continuously acquire the instantaneous voltage values ​​across the capacitor at a sampling frequency of 5000 times per second using a voltage sensor connected in parallel across the shared bus capacitor, and convert these analog signals into digital real-time voltage waveform data. The control module inputs this real-time voltage waveform data into an internally integrated phase-locked loop (PLL) circuit. The PLL searches the input voltage waveform through closed-loop feedback control and outputs the phase angle of the voltage waveform at the current moment. For example, if it detects that the voltage waveform is crossing zero from negative to positive at the current moment, it outputs a phase angle of 0 degrees as the instantaneous phase characteristic. Simultaneously, the control module inputs the real-time voltage waveform data into an amplitude detection circuit. This circuit records the maximum voltage value in the most recent cycle using a peak-hold algorithm and outputs the current voltage amplitude of 311 volts as the instantaneous amplitude characteristic.

[0163] S2042. Based on the instantaneous phase characteristics and instantaneous amplitude characteristics, power conversion is performed on various types of electrical energy and compensation electrical energy to obtain an orthogonal injection current that is orthogonal to the phase of the real-time voltage waveform. The orthogonal injection current is then injected into the shared bus capacitor so that the orthogonal injection current absorbs electrical energy at the peak moment of the shared bus capacitor voltage and releases electrical energy at the zero-crossing moment of the shared bus capacitor voltage. Here, the orthogonal injection current refers to the injection current that is phased with the real-time voltage waveform by a preset angle.

[0164] Specifically, the control module sends the instantaneous phase characteristics obtained from the phase-locked loop circuit and the instantaneous amplitude characteristics obtained from the amplitude detection circuit to the internal quadrature current generation unit. This unit calculates the target current phase, which differs from the current voltage phase by a preset quadrature angle, such as 90 degrees, and calculates the instantaneous value of the quadrature current to be injected, combining this with the instantaneous amplitude characteristics. The control module sends this instantaneous quadrature current value as a reference signal to the power electronic converter connected to multiple power sources. The converter's internal pulse width modulation circuit adjusts the duty cycle of the power switching transistors in real time based on this reference signal, ensuring that the current waveform output by the photovoltaic system, energy storage system, and thermal compensation power is consistent with the reference signal, generating an injection current orthogonal to the real-time voltage waveform. This current is then injected into the shared bus capacitor. Because the injected current is orthogonal to the voltage phase, when the capacitor voltage is at its peak, the injected current is exactly zero or absorbs energy in the reverse direction; when the capacitor voltage is at its zero-crossing point, the injected current reaches its peak and releases energy into the capacitor. This step is used to generate an injection current that is orthogonal to the phase of the bus voltage waveform. This phase relationship allows the injection current to absorb excess energy at voltage peaks and replenish energy gaps when the voltage crosses zero, thereby actively suppressing voltage fluctuations.

[0165] For example, the control module can input the instantaneous phase characteristics (currently 0 degrees, voltage zero-crossing point) obtained from the phase-locked loop circuit, and the instantaneous amplitude characteristics (311 volts) obtained from the amplitude detection circuit into its internal quadrature current generation unit. This unit calculates the peak current to be injected at the current voltage zero-crossing moment based on a preset quadrature angle of 90 degrees, ensuring the current direction matches the voltage change trend. The control module sends this target current value as a reference signal to the power electronic converter connecting the photovoltaic system, energy storage system, and thermal compensation energy. The converter's internal pulse width modulation circuit adjusts the duty cycle of the power switching transistors in real time based on this reference signal. This allows the DC power output from the photovoltaic array, the DC power released from the energy storage battery, and the compensation energy converted from the thermal side to be transformed into a sinusoidal injection current with a 90-degree phase difference from the real-time voltage waveform. This current is then injected into the shared bus capacitor. When the bus capacitor voltage reaches its peak value of 311 volts at the next instant, the injected current is exactly at zero because it is in phase with the voltage. It neither absorbs nor releases electrical energy. When the voltage starts to drop from the peak value, the injected current starts to reverse and absorbs electrical energy from the capacitor for storage. When the voltage crosses zero again, the injected current reaches a positive peak value and releases the previously absorbed electrical energy back to the capacitor.

[0166] The orthogonal injection current, which is orthogonal to the real-time voltage waveform, has a phase difference of 90 degrees from the real-time voltage waveform across the shared bus capacitor. This current does not generate a net exchange of active power when injected into the capacitor; instead, it achieves reactive power throughput. The reason for the orthogonality is to utilize the voltage-current phase relationship of the capacitor element: when the current phase leads the voltage by 90 degrees, the current is exactly zero at the voltage peak and reaches its maximum value at the voltage zero crossing. This allows the injected current to automatically stop charging when the voltage is at its highest and to fully discharge when the voltage is zero, achieving energy-loss-free suppression of bus voltage fluctuations.

[0167] The orthogonal injection current absorbs energy at the peak of the shared bus capacitor voltage and releases energy at the zero-crossing point of the shared bus capacitor voltage because the phase relationship between the orthogonal injection current and the voltage determines the timing of power exchange: when the voltage crosses the zero point from negative to positive, the current reaches its maximum positive value. At this time, the current direction is consistent with the voltage change direction, and electrical energy is injected into the capacitor from the power source side, causing the capacitor voltage to rise. When the voltage rises to its positive peak, the current drops to zero, stopping the injection of electrical energy, and the capacitor maintains the voltage using its stored electrical energy. Subsequently, the voltage begins to fall, the current becomes negative and gradually increases, and it begins to absorb and store electrical energy from the capacitor. When the voltage crosses zero again, the negative current reaches its peak, and the absorbed electrical energy reaches its maximum. This phase coordination allows the injected current to charge when the capacitor needs to charge and discharge when it needs to discharge, thereby actively smoothing voltage fluctuations.

[0168] The technical effect of this solution in this embodiment is as follows: By introducing orthogonal injection current technology, active shaping and zero-disturbance optimization of the bus voltage waveform are achieved during the power injection process. This method acquires the instantaneous phase and amplitude characteristics of the shared bus capacitor voltage in real time, performs power conversion on various types of electrical energy and compensation energy, and generates an injection current orthogonal to the voltage waveform. This orthogonal injection current absorbs energy from the capacitor at the voltage peak and releases energy to the capacitor at the voltage zero-crossing point, ensuring that the injection process itself does not deliver net active power to the capacitor, thereby avoiding additional voltage fluctuations. Simultaneously, by absorbing excess energy at the peak and replenishing the energy gap at the zero-crossing point, the injection current actively smooths the voltage waveform, improving the power quality of the bus voltage and solving the problems of disturbance to the bus voltage and voltage waveform distortion caused by the power injection process.

[0169] In one possible design, S201, the ability to acquire the state of charge of multiple power sources, the state of charge of the energy storage system, and the inertia output capability of the shared bus capacitor, includes:

[0170] S2011, Capable of acquiring multiple initial electrical energy, state of charge, and inertia outputs from multiple power sources.

[0171] Specifically, by connecting voltage sensors in parallel and current sensors in series at the output of the photovoltaic array, the grid connection point, and the energy storage system interface, the output voltage and current signals of each power source can be collected in real time. These analog signals are then sent to the analog-to-digital converter (ADC) of the control module to be converted into digital power data, thereby acquiring various initial energy sources. Simultaneously, the battery management system of the energy storage system directly reads its state of charge percentage, and by setting a voltage detection circuit across the shared bus capacitor, the voltage fluctuation data across the capacitor is collected in real time. The control module calculates the inertia output capability based on the rate of voltage change per unit time. This step provides the control module with the raw energy parameters of each power source and the core state variables of the system, serving as the basis for subsequent energy preprocessing and system state judgment.

[0172] Among them, "multiple initial electrical energy" refers to the raw electrical energy directly output from power sources such as photovoltaic systems, power grids, and energy storage systems without any processing. Its voltage, current, and waveform parameters may vary and may not match the rated parameters of the shared bus capacitor. "Multiple electrical energy" refers to standardized electrical energy obtained by differentiated preprocessing of multiple initial electrical energies, meeting the preset rated parameter requirements of the shared bus capacitor. The difference lies in the following: initial electrical energy is in its "raw state." For example, the voltage output by a photovoltaic system may be fluctuating DC from 200V to 500V, the grid output may be 380V AC, and the energy storage system output may be 48V DC. After preprocessing, the multiple electrical energies are uniformly adjusted to match the rated voltage (e.g., 650V DC), rated current range, and smooth waveform of the shared bus capacitor, eliminating the electrical differences between the various sources.

[0173] S2012. Differentiated preprocessing is performed on multiple initial electrical energies to obtain multiple electrical energies; wherein, the differentiated preprocessing is used to eliminate the differences between each electrical energy and the preset rated parameter requirements of the shared bus capacitor, so that the multiple electrical energies can be adapted to the preset rated parameter requirements.

[0174] Specifically, the control module can collect real-time voltage and current values ​​of the DC power output from the photovoltaic system, the DC power from the grid after rectification, and the DC power released by the energy storage system, and send them to their respective power electronic converters. Each converter is equipped with an independent voltage regulation circuit and current limiting circuit. Based on the preset rated voltage and current parameters of the shared bus capacitor, the control module sends different adjustment commands to the photovoltaic converter, grid converter, and energy storage converter: for photovoltaic power with excessively high voltage, it instructs its step-down circuit to reduce the voltage to the rated value; for energy storage power with excessively low voltage, it instructs its step-up circuit to increase the voltage to the rated value; for grid rectified power with large current ripple, it instructs its filter circuit to smooth the current waveform. After these targeted voltage regulation, current limiting, and waveform smoothing processes, the initial electrical energy is converted into standardized electrical energy with voltage, current, and waveform that all meet the preset rated parameters of the shared bus capacitor, thus obtaining multiple types of electrical energy. This step is used to eliminate the differences in electrical parameters between various power sources and the shared bus capacitor, so that irregular electrical energy from different sources can be safely and efficiently injected into the bus capacitor.

[0175] The technical effect of this solution in this embodiment is as follows: By performing differentiated preprocessing on various initial electrical energy sources, it ensures that electrical energy from different power sources can uniformly adapt to the rated parameter requirements of the shared bus capacitor. After acquiring initial electrical energy from different sources such as photovoltaics, energy storage, and the power grid, this method performs differentiated processing on each source based on its characteristics, including maximum power point search, voltage matching and power regulation, and AC / DC conversion. This eliminates the differences between each electrical energy source and the preset rated parameters of the shared bus capacitor, ensuring that the processed electrical energy sources can all meet the capacitor's voltage, power, and other access requirements. This lays the foundation for the subsequent centralized convergence and coordinated power supply of multiple power sources, solving the problem of inconsistent electrical energy parameters from different power sources that cannot be directly connected to the shared bus capacitor.

[0176] In one possible design, multiple power sources include photovoltaic systems, energy storage systems, and the power grid. S2012, differentiated preprocessing of various initial electrical energies yields multiple types of electrical energy, including:

[0177] S20121. Obtain the bus voltage of the shared bus capacitor, the real-time maximum output power of the photovoltaic system, and the real-time power supply status of the power grid.

[0178] Specifically, a voltage sensor can be connected in parallel across the shared bus capacitor to collect the instantaneous voltage value across the capacitor in real time. The analog signal is then sent to the analog-to-digital converter (ADC) of the control module to be converted into a digital bus voltage. A current sensor and a voltage sensor are connected in series at the output of the photovoltaic array to collect the output current and voltage. The control module uses their product as the real-time maximum output power of the photovoltaic system. A voltage detection relay and a circuit breaker status sensor are installed at the grid connection point to collect the effective voltage value and the on / off status of the circuit breaker on the grid side, determining whether the grid is currently online and whether the voltage is stable, thereby obtaining the real-time power supply status of the grid. This step provides the control module with the current voltage level of the shared bus capacitor, the maximum available power generation capacity of the photovoltaic system, and the availability of the grid, serving as the basic input data for subsequently building the virtual inertia model.

[0179] S20122. Based on the bus voltage, state of charge, real-time maximum output power, and real-time power supply status, construct a virtual inertia model for the photovoltaic thermal energy storage system. The virtual inertia model is used to establish the coupling relationship between the energy absorbed or released by the shared bus capacitor per unit time and the voltage fluctuation rate across the shared bus capacitor.

[0180] Specifically, the virtual inertia model of the solar thermal energy storage system consists of three components: a parameter fusion layer, an inertia calculation layer, and a coupling relationship layer. The bus voltage, state of charge (SOC), real-time maximum output power, and real-time power supply status first enter the parameter fusion layer. This layer normalizes these four input parameters, generating a set of standardized state vectors. It also correlates the current bus voltage change rate with the SOC of the energy storage system to determine the system's current energy buffering capacity. This set of state vectors is then fed into the inertia calculation layer. Based on a preset virtual inertia algorithm, combined with the real-time maximum output power and the grid power supply status, this layer calculates the virtual inertia coefficient that the system can provide under the current state. This coefficient reflects the ability of the bus capacitor to absorb or release energy per unit time. Finally, the coupling relationship layer mathematically correlates the virtual inertia coefficient output by the inertia calculation layer with the bus voltage fluctuation rate, establishing a functional relationship with the voltage fluctuation rate as input and the energy absorbed or released by the capacitor as output, thus forming a complete virtual inertia model. This step is used to establish a mathematical model that can quantitatively describe the relationship between the energy throughput capacity of the shared bus capacitor and voltage fluctuations, providing a basis for subsequent differentiated preprocessing of the initial electrical energy.

[0181] For example, the control module inputs four parameters into its internally constructed virtual inertia model: the current voltage of the shared bus capacitor (650V), the state of charge of the energy storage system (60%), the real-time maximum output power of the photovoltaic system (40kW), and the real-time power supply status of the grid ("online and voltage stable"). The parameter fusion layer first normalizes these four input parameters and calculates the current voltage fluctuation rate as +2V / s. Combined with the 60% state of charge, it determines that the system has a moderate energy buffering capacity. Subsequently, the inertia calculation layer, based on the real-time maximum output power of 40kW and the online status of the grid, and using an internally preset virtual inertia algorithm, calculates the virtual inertia coefficient that the system can provide under the current state as 15kJ·s / V. Finally, the coupling layer correlates the virtual inertia coefficient with the voltage fluctuation rate to establish a clear mathematical correspondence: when the voltage fluctuation rate is +2V / s, the shared bus capacitor needs to absorb 30kJ of energy per unit time to maintain voltage stability, and when the voltage fluctuation rate is -2V / s, the capacitor needs to release 30kJ of energy. This step is used to establish a mathematical model that can quantitatively describe the relationship between the energy throughput capacity of the shared bus capacitor and voltage fluctuation.

[0182] S20123. Based on the virtual inertia model, different initial electrical energies are preprocessed to obtain various electrical energies.

[0183] Specifically, the real-time detected bus voltage fluctuation rate can be input into the constructed virtual inertia model. The model calculates the energy value that the shared bus capacitor needs to absorb or release at the current moment based on the internally established coupling relationship. The control module, based on this energy value, the real-time maximum output power of the photovoltaic system, the state of charge of the energy storage system, and the real-time power supply status of the grid, sends different adjustment commands to the power electronic converters connected to each power source: when the model calculation shows that the bus capacitor needs to absorb energy, the photovoltaic converter is instructed to appropriately increase its output voltage to increase power injection, the energy storage converter is instructed to switch to discharge mode to release power to the bus, and the grid converter is instructed to increase power input; when the model calculation shows that the bus capacitor needs to release energy, the photovoltaic converter is instructed to stabilize its output, the energy storage converter is instructed to switch to charging mode to absorb power from the bus, and the grid converter is instructed to reduce or stop power input. Each converter adjusts the duty cycle and voltage / current parameters of its internal power switches in real time according to instructions. This ensures that the initial electrical energy output from the photovoltaic system, energy storage system, and grid is specifically adjusted to meet the energy throughput requirements of the virtual inertia model, ultimately resulting in a variety of electrical energy sources that meet the stable operation requirements of the bus capacitor. This step is used to proactively adjust the output characteristics of each power source based on the quantitative calculation results of the virtual inertia model, so that the total electrical energy injected into the bus capacitor can accurately match the system inertia requirements, thereby actively suppressing voltage fluctuations.

[0184] The technical effect of this solution in this embodiment is as follows: By performing differentiated preprocessing on various initial electrical energy sources, it ensures that electrical energy from different power sources can uniformly adapt to the rated parameter requirements of the shared bus capacitor. After acquiring initial electrical energy from different sources such as photovoltaics, energy storage, and the power grid, this method performs differentiated processing on each source based on its characteristics, including maximum power point search, voltage matching and power regulation, and AC / DC conversion. This eliminates the differences between each electrical energy source and the preset rated parameters of the shared bus capacitor, ensuring that the processed electrical energy sources can all meet the capacitor's voltage, power, and other access requirements. This lays the foundation for the subsequent centralized convergence and coordinated power supply of multiple power sources, solving the problem of inconsistent electrical energy parameters from different power sources that cannot be directly connected to the shared bus capacitor.

[0185] In one possible design, multiple initial electrical energies include a first electrical energy, a third electrical energy, and a fifth electrical energy; multiple electrical energies include a second electrical energy, a fourth electrical energy, and a sixth electrical energy. In S20123, differentiated preprocessing is performed on these multiple initial electrical energies to obtain multiple electrical energies, including:

[0186] S201231. Perform a maximum power point search on the first electrical energy to obtain the second electrical energy; wherein, the first electrical energy is the electrical energy output by the photovoltaic system.

[0187] Specifically, a maximum power point search controller can be connected to the output of the photovoltaic array. This controller integrates a voltage sampling circuit, a current sampling circuit, and a pulse width modulation generator. The voltage and current sampling circuits collect the voltage and current values ​​output by the photovoltaic array in real time and send them to the microprocessor within the controller. The microprocessor uses a perturbation-observation method to calculate the current output power of the photovoltaic array and compares it with the power value at the previous moment: if the power increases, the voltage is adjusted in the same direction; if the power decreases, the voltage is adjusted in the opposite direction. Based on the comparison result, the microprocessor generates a corresponding pulse width modulation signal and sends it to the DC-DC converter connecting the photovoltaic array and the shared bus capacitor. By adjusting the duty cycle of the power switches inside the converter, the photovoltaic array is kept operating near the maximum power output point, thereby converting the unstable first electrical energy into a second electrical energy with stable voltage and maximum power. This step is used to extract the maximum usable electrical energy from the photovoltaic array under the current illumination conditions and ensure that its voltage parameters meet the requirements for subsequent injection into the bus capacitor.

[0188] S201232. Voltage matching and power regulation are performed on the third electrical energy to obtain the fourth electrical energy; wherein, the third electrical energy is the electrical energy output by the energy storage system.

[0189] Specifically, a bidirectional DC-DC converter can be connected to the output of the energy storage system. This converter integrates a voltage detection circuit, a current detection circuit, and a pulse width modulation (PWM) controller. The voltage detection circuit acquires the current output voltage value of the energy storage battery (e.g., 48V DC) in real time and sends it to the PWM controller. The controller compares this value with the preset rated voltage value of the shared bus capacitor (e.g., 650V DC) to calculate the required voltage boost factor. Simultaneously, the control module sends a power regulation command to the converter based on the output of the virtual inertia model, specifying the current power value required for the energy storage system to output. Based on the voltage matching requirements and the power regulation command, the PWM controller adjusts the duty cycle and switching frequency of the power switches inside the converter in real time. This ensures that the 48V DC output from the energy storage battery is boosted and regulated, converting it into a fourth type of electrical energy with a stable voltage of 650V and an output power consistent with the command value, which is then injected into the shared bus capacitor. This step is used to boost the low-voltage electrical energy output by the energy storage system to a voltage level matching the bus capacitor and precisely control its output power to meet the system inertia requirements.

[0190] S201233. The fifth electrical energy is converted from AC to DC and matched with voltage to obtain the sixth electrical energy; wherein, the fifth electrical energy is the electrical energy output by the power grid.

[0191] Specifically, a bidirectional AC / DC converter can be connected between the grid connection point and the shared bus capacitor. This converter integrates a rectifier circuit, a voltage detection circuit, and a pulse width modulation (PWM) controller. The voltage detection circuit collects the three-phase AC voltage value (e.g., 380V AC) input from the grid side in real time and sends it to the PWM controller. The controller first controls the power switches in the rectifier circuit to conduct in a specific sequence, converting the AC power into pulsating DC power. Then, the controller compares the voltage value of this pulsating DC power with the preset rated voltage (e.g., 650V DC) of the shared bus capacitor and adjusts the duty cycle of the power switches in the subsequent DC / DC boost circuit in real time, gradually increasing the voltage to a stable 650V DC. Simultaneously, the control module sends a power regulation command to the converter based on the output of the virtual inertia model, specifying the power value that needs to be absorbed from the grid. The PWM controller adjusts the conduction sequence of the switches accordingly, ensuring that the voltage and power of the final output power meet the rated parameter requirements of the bus capacitor. This step is used to convert the AC power input from the grid into DC power that matches the bus capacitor, and to precisely control its output power to meet the system's operating requirements.

[0192] The first type of electrical energy refers to the raw DC power directly output by the photovoltaic system. Its voltage and power fluctuate with changes in light intensity and temperature. For example, under sufficient sunlight, the output voltage is 500V and the power is 30kW, while under insufficient sunlight, it may drop to 200V and the power to 5kW. The second type of electrical energy refers to the stable and efficient DC power obtained after performing a maximum power point search on the first type of electrical energy. Its voltage is adjusted to the rated value (e.g., 650V) to match the shared bus capacitor, and its power is always maintained at the maximum value under the current sunlight conditions. The third type of electrical energy refers to the raw DC power directly output by the energy storage system. Its voltage depends on the current state of charge of the energy storage battery. For example, the output voltage is 52V when fully charged and drops to 44V when depleted. The fourth type of electrical energy refers to the standardized DC power obtained after voltage matching and power regulation of the third type of electrical energy. Its voltage is precisely boosted to the rated voltage of the bus capacitor (650V), and the output power is adjusted in real time according to system commands. The fifth type of electrical energy refers to the raw AC power directly output by the grid, such as standard three-phase 380V AC power. The sixth type of electrical energy refers to the DC electrical energy obtained by converting the fifth type of electrical energy into AC and DC and matching the voltage. Its voltage is converted into a stable 650V DC, and the amount of power absorbed from the power grid can be adjusted as needed.

[0193] The technical effect of this solution in this embodiment is as follows: It performs maximum power point search on the first electrical energy output by the photovoltaic system to ensure that the photovoltaic system always operates in its optimal output state; it performs voltage matching and power regulation on the third electrical energy output by the energy storage system to ensure that its output parameters accurately match the connection requirements of the shared bus capacitor; and it performs AC-DC conversion and voltage matching on the fifth electrical energy output from the grid, converting AC power into qualified DC power before injecting it into the bus. These three differentiated preprocessing methods ensure that electrical energy with different characteristics can meet the rated parameter requirements of the shared bus capacitor, laying the foundation for subsequent coordinated power supply from multiple sources and solving the problem of large differences in the characteristics of electrical energy from different power sources, making it difficult to uniformly connect them to the shared bus capacitor.

[0194] Figure 3 A flowchart illustrating the power supply method for the photovoltaic thermal energy storage system provided in this application embodiment. Figure 2 In this embodiment, in Figure 2 Based on the provided embodiments, the power supply method for the photovoltaic thermal energy storage system is further explained. The power supply method for the photovoltaic thermal energy storage system includes:

[0195] S301. Obtain the state of charge of multiple electrical energy and energy storage systems from multiple power sources and the inertia output capability of the shared bus capacitor; wherein, the inertia output capability is used to represent the ability of the shared bus capacitor to suppress voltage fluctuations across the shared bus capacitor.

[0196] S302. When the state of charge is higher than or equal to the preset state threshold and the inertia output capability is higher than or equal to the preset capability threshold, multiple types of electrical energy are injected into the shared bus capacitor, and the shared bus capacitor supplies power to the photovoltaic thermal energy storage system; wherein, the shared bus capacitor is electrically connected to multiple power sources.

[0197] S303. When the state of charge is lower than the preset state threshold and the inertia output capability is lower than the preset capability threshold, the heat medium temperature of the photovoltaic thermal energy storage system, the heat storage status of the preset thermal energy storage device, and the heat demand of the preset heat load are obtained, and an inertia compensation command is generated based on the heat medium temperature, the heat storage status, and the heat demand; wherein, the inertia compensation command is used to adjust the operating status of the preset thermal side in the photovoltaic thermal energy storage system to provide compensation power for the shared bus capacitor.

[0198] S304. Inject various types of electrical energy and compensation electrical energy into the shared bus capacitor, and supply power to the photovoltaic thermal energy storage system through the shared bus capacitor; wherein, compensation electrical energy refers to the electrical energy released or converted by the preset thermal side after the inertia compensation command is executed, and the shared bus capacitor is electrically connected to the preset thermal side.

[0199] S301-S304 are similar to S201-S204, and will not be described again in this embodiment.

[0200] S305. When the state of charge is lower than the preset state threshold and the inertia output capability is higher than the preset capability threshold, a pre-compensation command is generated based on the heat medium temperature, heat storage state and heat demand. The pre-compensation command is used to instruct the preset heat side to reduce the operating power of the preset heat load when the state of charge is lower than the preset state threshold and the inertia output capability is higher than the preset capability threshold, so as to reserve the electrical energy saved by the preset heat side for the shared bus capacitor. The preset heat load is set on the preset heat side.

[0201] Specifically, the control module can compare the state of charge (SBC) of the energy storage system with a preset threshold and the inertia output capacity of the shared bus capacitor with a preset capacity threshold in real time. When it is determined that the SBC is lower than the preset threshold while the inertia output capacity is higher than or equal to the preset capacity threshold, the control module immediately reads the heat transfer medium temperature collected by the temperature sensor, the heat storage status fed back by the heat storage tank level gauge, and the heating demand data transmitted from the building automation system. The control module makes logical judgments based on conditions such as whether the heat transfer medium temperature is higher than the minimum temperature required for heating, whether the heat storage status is sufficient, and whether the heating demand is low. If all three conditions are met for energy transfer, a pre-compensation command is generated and sent to the power regulator connected to the heat load, instructing it to reduce the operating power of the heat pump or electric heating equipment. This step is used to reduce the power consumption on the heating side in advance when the energy storage capacity is insufficient but the inertia support capacity of the bus capacitor is still sufficient, reserving this part of the power for possible power supply gaps in the future.

[0202] For example, the control module of a solar thermal energy storage system detects that the state of charge of the energy storage battery has dropped to 25%, below the preset 30% threshold. However, the voltage fluctuation of the shared bus capacitor is smooth, and the calculated inertial output capacity is 80%, still higher than the preset 50% capacity threshold. At this time, the control module immediately reads the temperature sensor data on the heat medium pipeline, showing that the current heat medium temperature is 58°C. It obtains the heat storage status of 75% from the heat storage tank monitoring system and learns from the building automation system that the heating demand in the office area is low because the indoor temperature has reached the set value. The control module comprehensively judges that: the heat medium temperature is sufficient, the heat storage capacity is abundant, and the heating demand is not high, so it is possible to reserve electrical energy from the heating side in advance. Therefore, the control module sends a pre-compensation command to the frequency converter and electric regulating valve connected to the underfloor heating circulation pump, instructing them to reduce the operating frequency of the underfloor heating circulation pump from 50Hz to 30Hz, and at the same time reduce the opening of the hot water valve leading to the office area. After executing the instruction, the thermal side saves 3 kWh of electrical energy per hour. This electrical energy is not used immediately, but is reserved so that it can be quickly injected into the shared bus capacitor when the bus capacitor inertia decreases or the load suddenly increases.

[0203] In this context, heat transfer medium temperature refers to the actual temperature of the medium used to transfer heat in the solar thermal energy storage system, such as water, heat transfer oil, or air, at the current moment. It reflects the quality of the available thermal energy on the heating side. For example, a temperature sensor installed on the heat transfer medium pipeline might read a current heat transfer medium temperature of 65°C. Thermal storage status refers to the ratio of the currently stored heat in a preset thermal storage device, such as a hot water storage tank or phase change thermal storage tank, to its maximum thermal storage capacity. It is usually expressed as a percentage and is used to measure how much reserve thermal energy is available for use on the heating side. For example, if a thermal storage tank has a total thermal storage capacity of 1000 kWh and currently stores 700 kWh of heat, its thermal storage status is 70%. Heat demand refers to the actual amount of heat required by the heat load connected to the solar thermal energy storage system, such as radiators, underfloor heating coils, or industrial heating equipment at the current moment. This step is used to determine how much external heat energy needs to be consumed. For example, if a building automation system signals that the current indoor temperature has reached the set value, then the heat demand is low.

[0204] S306. When the state of charge is higher than the preset state threshold and the inertia output capability is lower than the preset capability threshold, an energy storage compensation command is generated based on the capability gap between the inertia output capability and the preset capability threshold. The energy storage compensation command is used to instruct the energy storage system to discharge to the shared bus capacitor with a power greater than the preset rated discharge power of the energy storage system.

[0205] Specifically, the control module can compare the state of charge (SOC) of the energy storage system with a preset SOC threshold and the inertia output capability of the shared bus capacitor with a preset capability threshold in real time. When it is determined that the SOC is higher than the preset SOC threshold but the inertia output capability is lower than the preset capability threshold, the control module immediately calculates the difference between the preset capability threshold and the current inertia output capability. This difference is taken as the capability deficit. Based on the magnitude of the capability deficit and the current SOC of the energy storage system, a corresponding energy storage compensation command is generated and sent to the bidirectional converter of the energy storage system, instructing it to discharge instantaneously to the shared bus capacitor at a value exceeding the preset rated discharge power. This step is used to enhance the voltage stability of the bus capacitor by allowing the energy storage system to discharge at a short time with excessive power when the stored energy is sufficient but the inertia support capability of the bus capacitor is insufficient.

[0206] For example, the control module of a solar thermal energy storage system detects in real time that the state of charge (SOC) of the energy storage battery is 80%, higher than the preset 30% threshold. However, the voltage of the shared bus capacitor drops significantly at the moment the air conditioner compressor starts, and the calculated inertial output capability is only 30%, lower than the preset 50% capability threshold. The control module immediately calculates the difference between the preset capability threshold and the current inertial output capability, finding a capability deficit of 20%. Based on this deficit and the current sufficient SOC of the energy storage battery, the control module generates an energy storage compensation command and sends it to the bidirectional energy storage converter, instructing it to instantaneously discharge to the shared bus capacitor with a power value exceeding 1.5 times the preset rated discharge power. The energy storage system responds immediately, injecting 45kW of power (its rated discharge power is 30kW) into the bus capacitor within 5 seconds, rapidly improving the stability of the bus voltage and preventing equipment shutdown that could be caused by insufficient capacitor inertia.

[0207] The pre-compensation command refers to a signal sent by the control module to the thermal-side equipment when the energy storage system's power is insufficient but the shared bus capacitor's inertia support capacity is still adequate. This signal is used to pre-emptively reduce the operating power of the thermal load, reserving the saved energy for the shared bus capacitor for later use. This proactively reduces the energy consumption of non-critical thermal loads to reserve electrical resources before a power shortage on the electrical side is imminent. For example, if the control module detects that the energy storage battery has only 20% charge remaining and the bus capacitor voltage is stable, but anticipates a high-power device starting in 10 minutes, it sends a pre-compensation command to the ground source heat pump, instructing it to temporarily reduce its heating power to the underfloor heating system, reserving the saved 5kW of energy within the system.

[0208] An energy storage compensation command is a signal sent by the control module to the energy storage system when the system has sufficient charge but the shared bus capacitor's inertia support capacity is insufficient. This signal instructs the system to discharge briefly at a power level exceeding its rated power. The purpose is to rapidly inject energy into the bus capacitor to enhance its voltage stability. This is used to compensate for the inertia gap by instantaneously exceeding the power output of the energy storage system when the bus capacitor's buffering capacity decreases. For example, if the control module detects that the energy storage battery is at 80% charge and the bus voltage is fluctuating drastically, it sends an energy storage compensation command to the energy storage converter, instructing it to instantaneously discharge 2kW at 1.5 times its rated power to the bus capacitor for 5 seconds to suppress voltage drops.

[0209] The technical effect of this solution in this embodiment is as follows: When the energy storage state of charge is lower than the preset state threshold but the shared bus capacitor inertia output capability is high, by controlling the thermal side to reduce the thermal load operating power, the saved electrical energy is reserved for the shared bus capacitor. This can enhance the bus energy reserve without consuming additional energy storage power, effectively delay bus voltage fluctuations, and ensure continuous and stable power supply to the system. When the energy storage state of charge is higher than the preset state threshold but the shared bus capacitor inertia output capability is insufficient, the energy storage system is controlled to discharge to the bus capacitor at a rate greater than the preset rated discharge power according to the inertia capability deficit. This can quickly make up for the bus inertia support gap, strongly suppress voltage fluctuations, and improve the system's dynamic response speed and anti-disturbance capability. Through precise adaptation and adjustment of the two operating conditions, the system power supply stability is enhanced, and the problem of weak adjustment capability under a single operating condition is solved.

[0210] In one possible design, S306 generates energy storage compensation commands based on the capacity gap between the inertia output capability and a preset capability threshold, including:

[0211] S3061. Obtain the real-time voltage waveform of the shared bus capacitor, and extract the dynamic load characteristics of each electrical device in the solar thermal energy storage system from the real-time voltage waveform.

[0212] Specifically, a voltage sensor can be connected in parallel across the shared bus capacitor. This sensor continuously collects the instantaneous voltage value across the capacitor at a sampling frequency of thousands of times per second, and sends the collected analog voltage signal to the analog-to-digital converter (ADC) unit of the control module to convert it into digital real-time voltage waveform data. The load feature extraction unit built into the control module performs time-domain analysis and frequency-domain transformation processing on this voltage waveform data, separating the unique voltage disturbance characteristics generated by the start-up, shutdown, or power regulation of different electrical equipment from the amplitude, frequency, and rate of change of voltage fluctuations. These characteristics are then compared with a pre-stored equipment load feature database to identify which air conditioner compressor is starting, which fan is adjusting its speed, or which water pump is running at the current moment, and extract the corresponding dynamic load characteristics of each device. This step is used to analyze the real-time operating status and power change information of each electrical device from the subtle fluctuations in the bus voltage, providing an accurate basis for subsequent differentiation of equipment priorities and matching of power supply waveforms.

[0213] Among them, the real-time voltage waveform refers to the instantaneous value recording curve of the voltage across the shared bus capacitor that changes continuously over time. It reflects the amplitude fluctuation of the bus voltage at each moment and is used to represent the real-time state and trend of the voltage. For example, a voltage curve that fluctuates over time and is measured across the shared bus capacitor by an oscilloscope shows the complete process of the voltage dropping from 650V to 620V and then quickly recovering at the moment the air conditioner compressor starts.

[0214] Dynamic load characteristics refer to a unique combination of electrical parameters extracted from real-time voltage waveforms that can reflect the operating characteristics of different electrical equipment. These include characteristic quantities such as voltage change rate, fluctuation amplitude, duration, and periodicity, which are used to distinguish and identify the operating status of various electrical equipment. For example, a periodic fluctuation data extracted from a real-time voltage waveform has a fluctuation frequency of 50Hz, a fluctuation amplitude of 5V, and a duration of 2 seconds. These characteristics combined can determine that a 5kW rated power fan is operating stably.

[0215] S3062. Identify the types of multiple electrical devices currently in operation in the solar thermal energy storage system and the instantaneous power demand curves corresponding to each electrical device based on the dynamic load characteristics, and retrieve the power supply priority of each electrical device from the preset device priority configuration table according to the type of each electrical device.

[0216] Specifically, the extracted dynamic load features can be input into a pre-trained equipment type recognition model via the control module. This model consists of three interconnected components: a feature extraction layer, a pattern matching layer, and an equipment type mapping layer. The dynamic load features first enter the feature extraction layer, which quantifies parameters such as the voltage waveform's rise slope, duration, and periodicity, converting them into a set of multi-dimensional feature vectors. These feature vectors are then fed into the pattern matching layer, which calculates the similarity between the input feature vectors and pre-stored standard feature templates for various types of electrical equipment in its internal memory, identifying the template with the highest matching degree. Finally, the equipment type mapping layer searches for the corresponding equipment type name in the mapping table based on the matched template index and outputs that name. Simultaneously, the control module also sends the raw voltage waveform data to the power analysis unit, extracting the instantaneous power demand curve for each device at the current moment. The control module uses the identified equipment type as the query keyword to search a preset equipment priority configuration table, which is stored in tabular form in the control module's memory and explicitly records the power supply priority value corresponding to each equipment type. This step is used to determine which devices are using electricity, how much power each device needs, and their priority in ensuring power supply, providing a basis for decision-making in generating differentiated energy storage compensation instructions.

[0217] For example, the control module of a solar thermal energy storage system extracts a set of dynamic load characteristics from the real-time voltage waveform of the shared bus capacitor. These characteristics include a 2-second periodic fluctuation at 50Hz, a 0.3-second voltage drop, and a slowly rising voltage change. After inputting these characteristics into a device type identification model, the control module identifies the currently operating devices as a fan running stably, an air conditioning compressor that has just started, and a water pump undergoing speed adjustment. Simultaneously, the control module analyzes the voltage waveform to determine that the fan's instantaneous power demand is 3kW with a stable curve, the air conditioning compressor's instantaneous power demand jumps from 0kW to 10kW within 0.3 seconds and then drops back to 6kW, and the water pump's instantaneous power demand gradually increases from 2kW to 4kW within 2 seconds. Subsequently, the control module uses the identified device type as the query keyword to search a preset device priority configuration table. This table explicitly records that the air conditioning compressor's power supply priority is 1, the fan's is 2, and the water pump's is 3. This step is used to determine which devices in the current system are using electricity, how much power each device needs, and their priority in ensuring power supply, providing a basis for decision-making in generating differentiated energy storage compensation instructions.

[0218] The instantaneous power demand curve is a continuous recording line showing the real-time change in power required by electrical equipment during operation. It reflects the equipment's energy demand at every instant and is used to accurately monitor power fluctuations during different stages such as startup, operation, and speed adjustment. For example, by monitoring the voltage and current changes during the startup of an air conditioner compressor, a curve can be plotted showing the power rapidly increasing from 0kW to 8kW and then falling back to 5kW within 0.5 seconds. The equipment priority configuration table is a two-dimensional data table pre-stored in the control module. Each row corresponds to a type of electrical equipment, and each column records the power supply priority value for that equipment. This provides the control module with a basis for judging the urgency of different equipment in power supply assurance. For example, the first row of the table records "Air Conditioner Compressor - Priority 1", the second row records "Fan - Priority 2", and the third row records "Water Pump - Priority 3". Power supply priority is an indicator expressed by numbers or levels, used to indicate which devices should receive priority power when power resources are limited. This step is used to determine the order of power allocation when multiple devices are running at the same time. For example, the smaller the value, the higher the priority. The power supply priority of an air conditioner compressor is 1, which means that it will receive power matching first during energy storage compensation.

[0219] S3063. Generate energy storage compensation instructions based on instantaneous power demand curves, capacity deficits, and power supply priorities of each electrical device; wherein, the energy storage compensation instructions are used to instruct the energy storage system to discharge to the shared bus capacitor with a power greater than the preset rated discharge power, and to make the time-domain waveform of the discharge power preferentially match the instantaneous power demand curve of the electrical device with the highest power supply priority.

[0220] Specifically, the control module uses the instantaneous power demand curve of the highest-priority power-consuming equipment as the target waveform. Based on the magnitude of the capacity deficit, it calculates the power amplitude that the energy storage system needs to compensate for. This amplitude is then time-domain aligned with the target waveform to generate a discharge power command waveform that matches the instantaneous power demand curve but whose amplitude is limited by the capacity deficit. The control module converts this command waveform into an analog signal or digital communication command and sends it to the bidirectional converter of the energy storage system, instructing it to discharge to the shared bus capacitor according to this waveform. This step generates an energy storage discharge command that accurately matches the power consumption waveform of critical equipment, ensuring that the compensation energy output by the energy storage system prioritizes the instantaneous power demand of the most important equipment.

[0221] For example, the control module has identified the currently operating equipment and determined that the highest priority power supply device is the air conditioner compressor. Its instantaneous power demand curve shows that the power jumps from 0kW to 10kW within 0.3 seconds after the compressor starts, then drops back to 6kW. Simultaneously, the control module calculates a 5kW capacity gap between the current shared bus capacitor's inertial output capacity and the preset capacity threshold. Based on this data, the control module generates an energy storage compensation command: the command requires the energy storage system to discharge to the bus capacitor at an instantaneous power of 35kW, exceeding its rated discharge power (30kW), and the time-domain waveform of the discharge power must strictly match the instantaneous power demand curve of the air conditioner compressor, i.e., initially outputting a peak power of 10kW within 0.3 seconds, then decreasing to a continuous power supply of 6kW. This command is sent to the energy storage bidirectional converter to ensure that the waveform of the released electrical energy from the energy storage system is synchronized with the power consumption rhythm of the critical equipment. This step is used to generate a discharge command that accurately matches the power consumption waveform of the most important equipment, ensuring that the limited energy storage compensation power prioritizes meeting the instantaneous power demand of the critical load.

[0222] S3064. According to the energy storage compensation instruction, the electrical energy output by the energy storage system is injected into the shared bus capacitor with a time-domain waveform that matches the instantaneous power demand curve of the electrical equipment with the highest power supply priority, so that when the shared bus capacitor discharges to each electrical equipment, the shared bus capacitor prioritizes ensuring the power demand of the electrical equipment with the highest power supply priority.

[0223] Specifically, after receiving the energy storage compensation command from the control module, the bidirectional converter of the energy storage system contains a reference signal whose waveform matches the instantaneous power demand curve of the highest priority power-consuming equipment. The pulse width modulation circuit inside the bidirectional converter adjusts the duty cycle of the power switching transistors in real time based on this reference signal. This ensures that the DC power released from the energy storage battery, after conversion, outputs a pulsating energy whose voltage and current waveforms over time perfectly match the reference signal. This energy is then injected into the shared bus capacitor. When the shared bus capacitor discharges to all power-consuming equipment, since the capacitor voltage is determined by the waveform of the injected energy, the highest priority power-consuming equipment receives the corresponding waveform of energy from the bus at the exact moment it needs it. This step ensures that the compensation energy released by the energy storage system accurately matches the real-time power consumption rhythm of critical equipment, allowing the shared bus capacitor to automatically prioritize the instantaneous power demand of the most important equipment during power supply.

[0224] For example, after receiving an energy storage compensation command from the control module, the bidirectional energy storage converter contains a reference signal that matches the instantaneous power demand curve of the air conditioner compressor. This signal requires the converter to output a peak power of 10kW within 0.3 seconds, then drop back to 6kW. The pulse width modulation circuit inside the bidirectional converter adjusts the duty cycle of the power switching transistors in real time based on this reference signal. This ensures that the DC power released from the energy storage battery is converted into a pulsating electrical energy output with voltage and current waveforms that perfectly match the compressor's demand curve. This electrical energy is then precisely injected into the shared bus capacitor. At this time, the running air conditioner compressor, fan, and water pump are simultaneously connected to the shared bus capacitor. Since the capacitor voltage is determined by the waveform of the injected electrical energy, when the capacitor discharges to all devices, the air conditioner compressor receives the corresponding waveform of electrical energy from the bus precisely at the moment it needs high power during startup, while the fan and water pump receive power from the remaining energy distribution. This step is used to ensure that the compensation power released by the energy storage system can accurately match the real-time power consumption rhythm of critical equipment, so that the shared bus capacitor can automatically prioritize the instantaneous power demand of the highest priority air conditioning compressor when supplying power.

[0225] The technical effect of this solution in this embodiment is as follows: During the process of the energy storage system performing over-rated power inertia compensation, the dynamic load characteristics of each electrical device are obtained by extracting the real-time voltage waveform of the shared bus capacitor. The current operating equipment type, instantaneous power demand curve is identified and matched with the corresponding power supply priority. In this way, an energy storage compensation command that fits the actual load demand is generated, so that the discharge power time-domain waveform of the energy storage system is consistent with the instantaneous power demand curve of the highest priority device. This allows the bus capacitor to prioritize meeting the power demand of high-priority electrical devices when discharging, realizing the coordinated optimization of inertia compensation and load power supply, improving the targeting of power supply, and solving the problems of mismatch between energy storage compensation and load demand and insufficient power supply guarantee for high-priority devices.

[0226] This application also provides a power supply system for a photovoltaic thermal energy storage system, including: multiple power sources, an energy storage system, a shared bus capacitor, a control module, and a preset thermal side.

[0227] Specifically, corresponding power electronic converters can be connected to the output terminals of the photovoltaic array, grid connection point, and energy storage battery pack, respectively. The DC output terminals of these converters are then connected in parallel to the positive and negative buses of a shared bus capacitor. A control module is connected to the communication interface of the battery management system of the energy storage battery pack. This control module is simultaneously connected to the control ports of the voltage sensors at both ends of the shared bus capacitor, the photovoltaic converter, the grid converter, and the energy storage converter via shielded twisted-pair cables. Communication lines are also connected to this control module from the controllers of the heat pump unit, electric regulating valve, and thermoelectric conversion device on the heating side. The temperature sensors and level gauges of the hot water storage tank, the temperature sensors of the terminal heating pipes, and the heat demand signal interfaces of the building automation system are all connected to the analog input module of the control module. Finally, the output terminal of the shared bus capacitor is connected to load equipment such as air conditioning compressors and fans via inverters or direct drives. This setup is used to build a complete hardware platform, enabling the control module to collect real-time status data from both the electrical and heating sides and send control commands to various actuators according to preset logic, achieving multi-source coordinated power supply.

[0228] Multiple power sources are used to output various types of electrical energy.

[0229] Specifically, multiple power sources can be configured. For example, a photovoltaic array can be installed on the roof, with its output connected to a first DC-DC converter via a DC cable. This converter processes the DC power fluctuating with changes in sunlight from the photovoltaic array through a maximum power point search and outputs it to a shared bus capacitor. A three-phase AC cable from the grid connection point can be connected to the AC input of a bidirectional AC / DC converter. This converter rectifies and boosts the AC power from the grid into DC power before outputting it to the shared bus capacitor. Finally, the positive and negative terminals of a battery storage array can be connected to the DC input of a bidirectional DC / DC converter. This converter boosts or bucks the DC power stored in the battery storage array before outputting it to the shared bus capacitor. These three power sources are each electrically connected to the shared bus capacitor through independent power electronic interfaces, collectively forming a multi-source power supply architecture.

[0230] Energy storage systems are used to store electrical energy.

[0231] Specifically, an energy storage battery cabinet consisting of multiple lithium iron phosphate cells connected in series can be installed in the photovoltaic-thermal energy storage system. The total capacity of the battery cabinet is designed to be 100kWh. Its positive and negative terminals are connected to the DC side of a bidirectional DC / DC converter via DC cables. The other side of the converter is connected to a shared bus capacitor. A battery management system is integrated inside the battery cabinet. This system collects the voltage and temperature data of each cell in real time through voltage sampling lines and current sensors, and sends this data to the control module through a communication interface. When the photovoltaic system generates excess power or the grid is in a low-price period, the control module sends a charging command to the bidirectional DC / DC converter. The converter adjusts the duty cycle of the power switch to step down the excess power on the shared bus capacitor and send it to the battery cabinet for storage. When discharge is required, the control module sends a discharge command, and the converter boosts the DC power stored in the battery cabinet and injects it into the shared bus capacitor.

[0232] The shared bus capacitor is electrically connected to multiple power sources and energy storage systems. It is used to receive and store electrical energy output from multiple power sources and to supply power to the photovoltaic-thermal energy storage system. The shared bus capacitor has inertia output capability, which is used to represent the ability of the shared bus capacitor to suppress voltage fluctuations across its terminals.

[0233] Specifically, a set of high-capacitance electrolytic capacitors or film capacitors can be installed in the system electrical cabinet. The positive terminals of these capacitors are connected in parallel with copper busbars to form a positive busbar, and the negative terminals are connected in parallel to form a negative busbar, forming a shared busbar capacitor. The positive and negative terminals of the first DC converter at the output end of the photovoltaic system, the positive and negative terminals of the DC side of the bidirectional AC / DC converter at the grid connection point, and the positive and negative terminals of the DC side of the bidirectional DC / DC converter connected to the energy storage system are all connected in parallel to the positive and negative busbars via cables. A voltage sensor is connected in parallel across the positive and negative terminals of the shared busbar capacitor. The sensor detects the voltage value across the capacitor in real time and sends it to the control module. The positive and negative output terminals of the shared busbar capacitor are connected to the inverter or direct drive circuit on the load side through a DC circuit breaker. The inverter converts the DC power into AC power to supply equipment such as air conditioning compressors and fans. Because capacitors inherently possess the physical characteristics of storing charge and resisting voltage surges, when the load changes abruptly or the power supply fluctuates, the shared bus capacitor can quickly absorb or release energy through its stored electrical energy, suppressing drastic voltage changes. This ability to suppress voltage fluctuations is called inertia output capability, and its magnitude is related to the capacitance value and the current voltage change rate. This setup establishes a physical common power collection point and voltage stabilization node, allowing electrical energy from multiple power sources to converge and stabilize before supplying the load, while simultaneously utilizing the capacitor's own electrical characteristics to provide inertia support for the system.

[0234] The control module is used to acquire the state of charge of the energy storage system, the inertia output capability of the shared bus capacitor, and when the state of charge is lower than the preset state threshold and the inertia output capability is lower than the preset capability threshold, it acquires the heat medium temperature of the solar thermal energy storage system, the thermal storage status of the preset thermal storage device, and the heat demand of the preset heat load.

[0235] Specifically, a state threshold of 30% and a capacity threshold of 50% can be pre-written into the microprocessor of the control module. It periodically reads the current state of charge (SOC) values ​​from the energy storage battery management system via its communication interface, and simultaneously receives real-time voltage signals from voltage sensors connected in parallel across the shared bus capacitor via its analog input interface. The microprocessor calculates the inertia output capacity based on the rate of voltage change per unit time. The microprocessor compares these two values ​​with internally stored thresholds. When it detects a SOC of 25% below 30% and an inertia output capacity of 20% below 50%, it immediately reads the current heat medium temperature value from the temperature sensor installed on the heat medium pipeline via its digital input interface, reads the heat storage state percentage from the water storage tank level gauge, and obtains the current end-point heating demand signal from the building automation system via its communication interface. This setting enables the control module to automatically initiate the acquisition program of thermal side state parameters under extreme conditions of insufficient electrical side resources, providing the data needed for subsequent decision-making regarding the allocation of thermal side resources.

[0236] The control module is also used to control multiple power sources to inject various types of electrical energy into the shared bus capacitor when the state of charge is higher than or equal to a preset state threshold and the inertia output capability is higher than or equal to a preset capability threshold. When the state of charge is lower than a preset state threshold and the inertia output capability is lower than a preset capability threshold, it generates an inertia compensation command based on the heat medium temperature, heat storage state, and heat demand. The inertia compensation command is used to adjust the operating state of the preset thermal side to provide compensation electrical energy for the shared bus capacitor.

[0237] Specifically, the microprocessor of the control module can execute different program branches based on the comparison results after completing the real-time acquisition and comparison of the energy storage state of charge and the inertia output capability of the bus capacitor. When the microprocessor determines that the state of charge is 80% higher than the preset 30% threshold and the inertia output capability is 70% higher than the preset 50% threshold, it simultaneously sends a high-level conduction signal to the photovoltaic converter, grid converter, and energy storage converter through the digital output port, instructing these three converters to inject all the electrical energy output from their respective power sources into the shared bus capacitor. When the microprocessor determines that the state of charge is 25% lower than the 30% threshold and the inertia output capability is 20% lower than the 50% threshold, it immediately calls the thermal side collaborative control sub-logic. Based on the previously acquired data such as the heat medium temperature of 58℃, the thermal storage state of 75%, and the low level of heat demand, it calculates the amount of electrical energy that needs to be transferred from the thermal side through the internal logic operation unit, and generates a set of inertia compensation instructions containing specific adjustment parameters, which is sent to the controllers of the heat pump unit and the electric regulating valve through the communication interface. This setting enables the control module to automatically switch power supply strategies based on the real-time status of the system, directly calling multiple power sources when electrical resources are sufficient, and initiating thermal-side collaborative compensation when electrical resources are insufficient.

[0238] The preset thermal side is electrically connected to the shared bus capacitor and the control module. The preset thermal side is used to receive the inertia compensation command sent by the control module and respond to the inertia compensation command to adjust its own operating state, release or convert the compensation energy, inject the compensation energy into the shared bus capacitor, and, together with the various electrical energy outputs from multiple power sources, power the photovoltaic thermal energy storage system through the shared bus capacitor.

[0239] Specifically, a heat pump unit and a thermoelectric conversion device can be installed on the thermal side. The power supply cable of the heat pump unit is connected to the positive and negative buses of the shared bus capacitor through a bidirectional power electronic interface. Simultaneously, the output of the thermoelectric conversion device is also connected to the same bus through another bidirectional power electronic interface. The controllers of the heat pump unit and the thermoelectric conversion device are connected to the communication interface of the control module via communication lines. An electric regulating valve is installed on the heat medium pipeline, and its actuator is also connected to the digital output port of the control module via a signal line. When the control module detects insufficient electrical resources, it sends an inertia compensation command to the heat pump unit controller through the communication interface, instructing it to reduce the heat output power and inject the saved electrical energy back into the shared bus capacitor through its power electronic interface. Simultaneously, it sends an opening adjustment signal to the electric regulating valve, changing the flow direction of the heat medium so that the high-temperature heat medium flows to the thermoelectric conversion device. This device converts the heat energy into direct current and injects it into the shared bus capacitor through its power electronic interface. These two portions of compensated power, along with various types of power output from photovoltaic, power grid, and energy storage systems, are gathered and stabilized in the bus capacitor before being continuously supplied to loads such as air conditioning compressors via an inverter.

[0240] This embodiment provides a power supply system for a photovoltaic thermal energy storage system. By acquiring the state of charge of the energy storage system and the output capacity of the shared bus capacitor inertia, the system uses multiple sources of power to supply power when the energy storage capacity is sufficient and the bus inertia support capacity is normal. However, under extreme conditions where the energy storage capacity is insufficient and the shared bus capacitor inertia support capacity decreases, the system no longer relies solely on electrical side resources. Instead, it combines the temperature of the heat transfer medium, the thermal storage state, and the heat demand on the thermal side to adjust the operation of the thermal side and output compensating power. The multi-source power and the thermal side compensating power are injected into the shared bus capacitor, which makes up for the power supply gap caused by insufficient energy storage resources and decreased capacitor buffer capacity. This improves the power supply reliability and power quality of the photovoltaic thermal energy storage system under multi-source fluctuations, load changes, and extreme conditions, and avoids the problems of power quality degradation and power outage.

[0241] This application also provides a photovoltaic-thermal energy storage integrated power supply system, including: a preset thermal energy storage device, a preset thermal load, a photovoltaic-thermal energy storage system, and a power supply system for the photovoltaic-thermal energy storage system.

[0242] Specifically, a hot water storage tank can be installed on the building's equipment floor as a pre-set thermal storage device. The tank contains a coil heat exchanger and a temperature sensor. The tank's inlet and outlet pipes are connected to the heat pump unit of the solar thermal storage system via valves. Underfloor heating coils and fan coil units are installed in the building's terminal heating areas as pre-set heat loads. The water supply pipes for these devices are connected to the outlet of the hot water storage tank via a circulating pump and an electric regulating valve. A photovoltaic array is installed on the roof, and an energy storage battery cabinet and a shared bus capacitor cabinet are installed in the equipment room. The photovoltaic array, energy storage battery, and grid connection point are all connected to the shared bus capacitor via power electronic converters, forming the power supply system for the solar thermal storage system. The control module in the power supply system is connected to the temperature sensor, level gauge, and terminal building automation system of the hot water storage tank via communication lines. Simultaneously, the power supply cable of the heat pump unit is connected to the output terminal of the shared bus capacitor. This step establishes an integrated energy platform that combines electrical energy storage and supply, thermal energy storage and utilization, and heat load consumption, enabling the electrical and thermal energy systems to share status information and coordinate energy regulation through the control module.

[0243] The power supply system of the solar thermal energy storage system is electrically connected to the preset thermal energy storage device, the preset heat load, and the solar thermal energy storage system. The power supply system of the solar thermal energy storage system is used to obtain the thermal energy storage status of the preset thermal energy storage device and the heat demand of the preset heat load, and generate inertia compensation commands based on the thermal energy storage status and heat demand. The compensation power is supplied through the preset thermal side, and at the same time, it supplies power to the preset thermal energy storage device, the preset heat load, and the solar thermal energy storage system. Among them, the inertia compensation commands are used to adjust the operating status of the preset thermal side to provide compensation power to the preset thermal energy storage device, the preset heat load, and the solar thermal energy storage system.

[0244] Specifically, the control module in the power supply system can be connected to the temperature sensor and level gauge installed inside the hot water storage tank via an analog input interface and shielded cable. This allows for real-time reading of the tank's current temperature and level, which are then converted into a percentage of the heat storage status. Simultaneously, the control module's communication interface is connected to the building automation system via an RS485 bus to obtain the heating demand signals from the terminal floor heating and fan coil units. The control module connects the heat pump unit's power supply cable to the output of the shared bus capacitor, enabling the heat pump unit to obtain electrical energy from the bus for heating. The heat pump unit itself is also considered part of the preset heating side, and its controller is connected to the control module via a communication line. When the control module detects insufficient energy storage on the electrical side and a decrease in bus inertia, it determines that the thermal side has the conditions for energy transfer based on the read thermal storage status (e.g., 80%) and heat demand (e.g., low level). It then generates an inertia compensation command and sends it to the heat pump unit controller, instructing it to reduce its heating power and inject the saved electrical energy back into the shared bus capacitor through its power electronic interface. This compensation electrical energy, together with the electrical energy from photovoltaic, energy storage, and the grid, is gathered in the bus capacitor and then supplied to the heat pump unit itself to maintain basic operation, to the electric heating auxiliary device of the hot water storage tank, and to the heat load equipment such as the terminal circulation pump through the output terminal of the same bus capacitor.

[0245] The preset thermal storage device is used to store the heat energy generated by the photovoltaic thermal energy storage system and to feed back the thermal storage status of the preset thermal storage device to the power supply system of the photovoltaic thermal energy storage system.

[0246] Specifically, a hot water storage tank can be installed on the building's equipment floor as a pre-installed heat storage device. The tank contains a coil-type heat exchanger, whose inlet and outlet are connected to the condenser side of the heat pump unit in the solar thermal energy storage system via insulated pipes. The heat generated by the heat pump unit during operation is transferred to the water in the tank for storage through the heat exchanger. Three temperature sensors and one liquid level sensor are installed at different heights inside the tank. The signal lines of these sensors are centrally connected to a field data acquisition module. This module converts the real-time collected temperature and liquid level values ​​into digital signals via a communication protocol. The output of the data acquisition module is connected to the communication interface of the control module in the power supply system of the solar thermal energy storage system via a shielded twisted-pair cable, sending the current average temperature and liquid level of the tank to the control module once per second. Based on the tank's volume, current average temperature, and liquid level, combined with the water's specific heat capacity, the control module calculates in real time the ratio of the total stored heat energy to the tank's maximum heat storage capacity, thus obtaining the percentage of heat storage status. This setup is used to create a physical device that can store thermal energy and provide real-time feedback on the amount of stored heat. This allows the power supply system's control module to monitor the energy reserves on the thermal side at any time, providing a basis for determining whether to call upon the thermal side for compensation.

[0247] The preset heat load is used to consume the heat energy generated by the solar thermal energy storage system, and the heat demand of the preset heat load is fed back to the power supply system of the solar thermal energy storage system.

[0248] Specifically, underfloor heating coils and fan coil units can be installed in the building's heating area as preset heat loads. The inlet pipes of these devices are connected to the outlet of the hot water storage tank via electric regulating valves and circulating pumps. Temperature sensors are installed in the indoor areas to detect the indoor temperature in real time and transmit it to the building automation system (BAS) via a wireless module. The BAS calculates the current hot water volume and supply temperature required by the terminal devices based on the difference between the indoor temperature and the set temperature, combined with a timetable and a building thermal model, generating a heat demand signal. This heat demand signal is transmitted through the BAS communication interface to the communication interface of the control module in the power supply system of the solar thermal energy storage system in a standard protocol format. Simultaneously, feedback modules are installed on the controllers of the electric regulating valves and circulating pumps to monitor the valve opening and pump operating frequency in real time, and transmit these signals reflecting the actual heat consumption status to the control module via a fieldbus for supplementary verification. This setup establishes a physical terminal capable of consuming heat energy and providing real-time feedback on its demand, allowing the power supply system's control module to monitor the energy consumption on the heating side at any time, providing a basis for decision-making regarding whether electrical energy can be transferred from the heating side.

[0249] This embodiment provides a photovoltaic-thermal energy storage integrated power supply system. By integrating a preset thermal energy storage device, a preset heat load, a photovoltaic-thermal energy storage system, and a power supply system, a comprehensive power supply architecture for the coordinated operation of electrical and thermal energy is constructed. The power supply system acquires the thermal storage status of the thermal energy storage device and the heat demand of the heat load in real time. When the electrical power supply capacity is insufficient, it accurately generates inertia compensation commands based on this thermal information, driving the thermal side to release or convert compensation electrical energy into the shared bus capacitor, while continuously supplying the required energy to the thermal energy storage device and the heat load. This design realizes bidirectional energy interaction and status information sharing between the electrical and thermal sides. Under extreme conditions such as energy storage power depletion or bus inertia decline, the system can make up for the power supply gap by tapping the energy regulation potential of the thermal side, avoiding power outages caused by relying solely on electrical resources. This significantly improves the operational stability and power supply reliability of the entire integrated power supply system under scenarios of multi-energy fluctuations and load changes.

[0250] Figure 4 This is a schematic diagram of a traditional solar thermal energy storage system and an energy storage system with independent power supply, provided in an embodiment of this application. Figure 5 This is a circuit block diagram of the power supply system for the photovoltaic thermal energy storage system provided in an embodiment of this application. Figure 4This demonstrates a current-technology-based power supply architecture that separates photovoltaic (PV), energy storage, and photovoltaic-thermal storage (PV-thermal) systems. In this scheme, the energy storage and DC grid are connected to the PV-storage-DC-flexible intelligent control cabinet via bidirectional power conversion ports, while the PV system is connected to the control cabinet via a unidirectional DC port. Ultimately, the control cabinet supplies power to loads such as the first and second PV-thermal storage systems via a DC bus, forming an independent power supply architecture for the PV, energy storage, and PV-thermal storage systems. There is a lack of direct energy coordination and state sharing mechanisms between the energy units. Figure 5 The system integrates photovoltaic systems, energy storage systems, and the power grid. Its core function is to achieve centralized allocation of multi-source power and efficient driving of air conditioning compressors through a shared bus capacitor and a single control system. For example... Figure 5 As shown, the photovoltaic system is connected to a shared bus capacitor via DC / DC1, and the energy storage system is connected to a shared bus capacitor via DC / DC2. The bus capacitor is then connected to the grid via DC / AC1 and to the photovoltaic-thermal storage system via DC / AC2. The control system is connected to DC / DC1, DC / DC2, DC / AC1, and DC / AC2 respectively, realizing coordinated control of multi-source power and load. Compared to... Figure 4 The independent power supply architecture of photovoltaic, energy storage and solar thermal energy storage systems achieves energy interconnection and state sharing of photovoltaic, energy storage and solar thermal energy storage systems through shared bus capacitors. It can actively suppress bus voltage fluctuations by relying on the virtual inertia adjustment strategy of the control system, improve power supply reliability and power quality under extreme conditions, and avoid hardware redundancy, thereby reducing system cost and complexity.

[0251] When the photovoltaic system has sufficient power, the generated DC power is sent to the bus after maximum power search through DC / DC1, and then to the compressor after frequency and voltage regulation through DC / AC2. The specific frequency and voltage regulation values ​​are adjusted by the control system based on the indoor temperature and the customer's set temperature.

[0252] The power supply system of a solar thermal energy storage system may also include a power supply system. Figure 6 The power system block diagram provided for the embodiments of this application is as follows: Figure 6 As shown, the input ports of the power system are connected to the bus, the power grid, and the generator, respectively, enabling multiple power sources. Its output provides multiple power supply interfaces, including VCC1, VCC2, SVCC, and the corresponding ground terminal GND, which are used to provide suitable operating voltages for different modules in the system, such as operational amplifiers, comparators, sampling devices, and main control devices. The overall architecture adopts a combination of isolated main power supply and BUCK step-down power supply, which can achieve stable voltage transformation and reliable power supply guarantee.

[0253] Figure 7 The control module block diagram provided in the embodiments of this application is as follows: Figure 7As shown, the first and second control devices typically sample digital signal processors (DSPs), advanced RISC machines (ARMs), microcontroller units (MCUs), and other similar devices. The first control device mainly implements main control functions such as signal acquisition, port control, and switching control. It mainly includes multi-channel current sampling circuits, voltage sampling circuits, temperature sampling circuits, pulse width modulation drive circuits, I / O drive, and I / O detection circuits. The second control device mainly implements external communication and typically has multiple communication circuits of different types, such as RS-485 interface circuits, Controller Area Network (CAN), and Ethernet. The RS-485 interface circuit is a hardware circuit used to implement the RS-485 communication standard. Its main function is to convert the digital signals inside the main controller into differential signals conforming to the RS-485 electrical characteristics for long-distance, interference-resistant industrial communication. The first communication circuit is connected to the first controller and is used to transmit control signals and status data between the first controller and other internal modules. The second communication circuit is an external extended communication interface for the second controller and is used to upload system operation data, fault information, etc. to the host computer or other external devices.

[0254] When the electricity generated by the photovoltaic system exceeds the electricity consumed by the solar thermal energy storage system, the control module, according to the customer-defined strategy, either transmits the excess electricity to the grid via DC / AC1 or stores it in the energy storage system via DC / DC2. The key consideration is whether to prioritize charging the batteries or transmitting the excess electricity to the grid. If battery power is prioritized, the battery will be charged first. When the photovoltaic system's power is insufficient, the control module, based on the customer-defined strategy (which may vary depending on the electricity price at different times), may draw power from the energy storage system or the grid. If the energy storage system malfunctions, the control module can switch the grid to the compressor via an internal relay, directly powering the solar thermal energy storage system. In the event of an AC grid outage, the solar thermal energy storage system can continue to be powered by the batteries and photovoltaic system, achieving zero-second switching.

[0255] By integrating the two systems into one through optimized design, bus capacitors, control modules, and auxiliary power systems are saved, reducing the complexity and cost of the hardware system. The control module software is integrated, and the entire system is controlled by a single master controller, improving system response speed, avoiding the incoordination between the two systems, enhancing the customer experience, and truly achieving 0-second switching.

[0256] Figure 8This is a schematic diagram of the power supply device for the photovoltaic thermal energy storage system provided in an embodiment of this application. Figure 8 As shown, the power supply device for the solar thermal energy storage system includes:

[0257] The first acquisition module 801 is used to acquire the state of charge of various electrical energy and energy storage systems output from multiple power sources and the inertia output capability of the shared bus capacitor; wherein, the inertia output capability is used to represent the ability of the shared bus capacitor to suppress voltage fluctuations across the shared bus capacitor.

[0258] The first injection module 802 is used to inject multiple types of electrical energy into the shared bus capacitor when the state of charge is higher than or equal to a preset state threshold and the inertia output capability is higher than or equal to a preset capability threshold, and to supply power to the photovoltaic thermal energy storage system through the shared bus capacitor; wherein, the shared bus capacitor is electrically connected to multiple power sources.

[0259] The second acquisition module 803 is used to acquire the heat medium temperature of the photovoltaic thermal energy storage system, the heat storage state of the preset thermal energy storage device, and the heat demand of the preset heat load when the state of charge is lower than the preset state threshold and the inertia output capability is lower than the preset capability threshold. Based on the heat medium temperature, heat storage state, and heat demand, it generates an inertia compensation command. The inertia compensation command is used to adjust the operating state of the preset thermal side in the photovoltaic thermal energy storage system to provide compensation power for the shared bus capacitor.

[0260] The second injection module 804 is used to inject various types of electrical energy and compensation electrical energy into the shared bus capacitor, and to supply power to the photovoltaic thermal energy storage system through the shared bus capacitor; wherein, the compensation electrical energy refers to the electrical energy released or converted by the preset thermal side after the inertia compensation command is executed, and the shared bus capacitor is electrically connected to the preset thermal side.

[0261] In one possible design, the power supply unit for the solar thermal energy storage system also includes:

[0262] The first generation module is used to generate a pre-compensation instruction based on the heat medium temperature, heat storage state, and heat demand when the state of charge is lower than the preset state threshold and the inertia output capability is higher than the preset capability threshold. The pre-compensation instruction is used to instruct the preset heat side to reduce the operating power of the preset heat load when the state of charge is lower than the preset state threshold and the inertia output capability is higher than the preset capability threshold, so as to reserve the electrical energy saved by the preset heat side for the shared bus capacitor. The preset heat load is set on the preset heat side.

[0263] The second generation module is used to generate an energy storage compensation command based on the capacity gap between the inertia output capability and the preset capability threshold when the state of charge is higher than the preset state threshold and the inertia output capability is lower than the preset capability threshold. The energy storage compensation command is used to instruct the energy storage system to discharge to the shared bus capacitor at a power greater than the preset rated discharge power of the energy storage system.

[0264] In one possible design, the second generation module includes:

[0265] The first acquisition unit is used to acquire the real-time voltage waveform of the shared bus capacitor and extract the dynamic load characteristics of each electrical device in the photovoltaic thermal energy storage system from the real-time voltage waveform.

[0266] The identification unit is used to identify the types of multiple electrical devices currently in operation in the solar thermal energy storage system and the instantaneous power demand curves corresponding to each electrical device based on dynamic load characteristics, and to retrieve the power supply priority of each electrical device from the preset device priority configuration table according to the type of each electrical device.

[0267] The first generation unit is used to generate energy storage compensation instructions based on the instantaneous power demand curve, capacity deficit, and power supply priority of each electrical device. The energy storage compensation instructions are used to instruct the energy storage system to discharge to the shared bus capacitor with a power greater than the preset rated discharge power, and to make the time-domain waveform of the discharge power preferentially match the instantaneous power demand curve of the electrical device with the highest power supply priority.

[0268] The first injection unit is used to inject the electrical energy output by the energy storage system into the shared bus capacitor in a time-domain waveform that matches the instantaneous power demand curve of the electrical equipment with the highest power supply priority, according to the energy storage compensation command. This ensures that when the shared bus capacitor discharges to each electrical equipment, it prioritizes the power demand of the electrical equipment with the highest power supply priority.

[0269] In one possible design, multiple power sources include a photovoltaic system, and the first injection module 802 includes:

[0270] The first establishment unit is used to establish a dynamic power allocation model on the power side based on the state of charge, inertia output capability, and real-time load power of the photovoltaic thermal energy storage system. The dynamic power allocation model on the power side is used to determine the injection priority and power ratio of multiple power sources injecting power into the shared bus capacitor.

[0271] The second generation unit is used to generate power allocation instructions based on the power allocation model on the power side. The power allocation instructions are used to prioritize injecting the power output of the photovoltaic system into the shared bus capacitor when the voltage fluctuation rate of the shared bus capacitor is lower than a preset rate threshold, and to configure the energy storage system in a fast response standby state so that the energy storage system can immediately discharge when the voltage fluctuation rate of the shared bus capacitor increases. The power allocation instructions are also used to prioritize injecting the power output of the energy storage system into the shared bus capacitor when the voltage fluctuation rate of the shared bus capacitor is higher than a preset rate threshold, and to configure the photovoltaic system in a continuous power supply standby state so that the photovoltaic system can continuously inject power when the voltage fluctuation rate of the shared bus capacitor decreases.

[0272] The second injection unit is used to inject various types of electrical energy into the shared bus capacitor in batches according to the power allocation instructions from the power side, based on injection priority and power distribution.

[0273] In one possible design, the second injection unit includes:

[0274] The first acquisition component is used to acquire the real-time voltage value and voltage change trend of the shared bus capacitor, and to construct a waveform shaping model based on the real-time voltage value and voltage change trend; wherein, the waveform shaping model is used to match the time-varying law of the injected power of various electrical energies with the voltage fluctuation phase of the shared bus capacitor.

[0275] The first generation component is used to generate waveform shaping injection instructions based on various electrical energy and waveform shaping models. The waveform shaping injection instructions are used to make the injected power decrease as the voltage of the shared bus capacitor increases when the voltage of the shared bus capacitor is in the rising phase, and to make the injected power increase as the voltage decreases when the voltage of the shared bus capacitor is in the falling phase.

[0276] The first injection component is used to inject various electrical energies into the shared bus capacitor in batches according to the waveform shaping injection command, based on the injection priority and power ratio, and in a decreasing or increasing trend.

[0277] In one possible design, the second injection module 804 includes:

[0278] The second acquisition unit is used to acquire the instantaneous phase characteristics and instantaneous amplitude characteristics of the real-time voltage waveform of the shared bus capacitor; wherein, the instantaneous phase characteristics are used to represent the phase angle of the real-time voltage waveform at the current moment, and the instantaneous amplitude characteristics are used to represent the amplitude of the real-time voltage waveform at the current moment.

[0279] The conversion unit is used to perform power conversion on various types of electrical energy and compensation electrical energy according to the instantaneous phase characteristics and instantaneous amplitude characteristics, to obtain an orthogonal injection current that is orthogonal to the phase of the real-time voltage waveform, and inject the orthogonal injection current into the shared bus capacitor, so that the orthogonal injection current absorbs electrical energy at the peak moment of the shared bus capacitor voltage and releases electrical energy at the zero crossing moment of the shared bus capacitor voltage; wherein, the orthogonal injection current refers to the injection current that is out of phase with the real-time voltage waveform by a preset angle.

[0280] In one possible design, the first acquisition module 801 includes:

[0281] The third acquisition unit is used to acquire various initial electrical energy, state of charge, and inertia output capabilities from multiple power sources.

[0282] The preprocessing unit is used to perform differentiated preprocessing on various initial electrical energies to obtain various electrical energies; wherein, the differentiated preprocessing is used to eliminate the differences between each electrical energy and the preset rated parameter requirements of the shared bus capacitor, so that the various electrical energies are adapted to the preset rated parameter requirements.

[0283] In one possible design, multiple power sources include photovoltaic systems, energy storage systems, and the power grid, and the pre-processing unit includes:

[0284] The second acquisition component is used to acquire the bus voltage of the shared bus capacitor, the real-time maximum output power of the photovoltaic system, and the real-time power supply status of the power grid.

[0285] The first building component is used to construct a virtual inertia model of the photovoltaic thermal energy storage system based on the bus voltage, state of charge, real-time maximum output power, and real-time power supply status. The virtual inertia model is used to establish the coupling relationship between the energy absorbed or released by the shared bus capacitor per unit time and the voltage fluctuation rate across the shared bus capacitor.

[0286] The preprocessing component is used to perform differentiated preprocessing on various initial electrical energies based on a virtual inertia model to obtain various electrical energies.

[0287] In one possible design, multiple initial electrical energies include a first electrical energy, a third electrical energy, and a fifth electrical energy; multiple electrical energies include a second electrical energy, a fourth electrical energy, and a sixth electrical energy; and a preprocessing component includes:

[0288] The search component is used to perform a maximum power point search on the first electrical energy to obtain the second electrical energy; wherein, the first electrical energy is the electrical energy output by the photovoltaic system.

[0289] The control component is used to perform voltage matching and power regulation on the third electrical energy to obtain the fourth electrical energy; wherein, the third electrical energy is the electrical energy output by the energy storage system.

[0290] The matching component is used to perform AC / DC conversion and voltage matching on the fifth electrical energy to obtain the sixth electrical energy; wherein the fifth electrical energy is the electrical energy output from the power grid.

[0291] The power supply device for the photovoltaic thermal storage system provided in this embodiment can perform... Figures 2 to 3 The technical solution of the power supply method embodiment of the photovoltaic thermal energy storage system shown herein, its implementation principle and technical effects are similar to those of the embodiment. Figures 2 to 3 The power supply method of the photovoltaic thermal energy storage system shown in the embodiment is similar and will not be described in detail here.

[0292] Figure 9 This is a schematic diagram of the hardware structure of the electronic device provided in an embodiment of this application. Figure 9As shown, the electronic device 90 includes at least one processor 901 and a memory 902. The electronic device 90 also includes a communication component 903. The processor 901, memory 902, and communication component 903 are connected via a bus 904.

[0293] In a specific implementation, at least one processor 901 executes computer execution instructions stored in memory 902, causing at least one processor 901 to implement a power supply method for a photovoltaic thermal energy storage system as described in the above embodiment.

[0294] The specific implementation process of processor 901 can be found in the above method embodiments, and its implementation principle and technical effect are similar. It will not be repeated here.

[0295] In the above embodiments, it should be understood that the processor 901 can be a Central Processing Unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), etc. The general-purpose processor can be a microprocessor or any conventional processor. The steps of the method disclosed in this invention can be directly implemented by a hardware processor, or implemented by a combination of hardware and software modules within the processor.

[0296] The memory 902 may include high-speed RAM memory, and may also include non-volatile memory (NVM), such as at least one disk storage.

[0297] Bus 904 can be an Industry Standard Architecture (ISA) bus, a Peripheral Component Interconnect (PCI) bus, or an Extended Industry Standard Architecture (EISA) bus, etc. Bus 904 can be divided into address bus, data bus, control bus, etc. For ease of illustration, the bus 904 in the accompanying drawings of this application is not limited to only one bus or one type of bus.

[0298] The above description of the functions implemented by electronic devices and main control devices has introduced the solutions provided by the embodiments of the present invention. It is understood that, in order to implement the above functions, the electronic device or main control device includes hardware structures and / or software modules corresponding to the execution of each function. By combining the units and algorithm steps of the various examples described in the embodiments of the present invention, the embodiments of the present invention can be implemented in hardware or a combination of hardware and computer software. Whether a function is executed by hardware or by computer software driving hardware depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of the technical solutions of the embodiments of the present invention.

[0299] This application also provides a computer-readable storage medium storing computer-executable instructions. When executed by a processor, these instructions are used to implement a power supply method for a photovoltaic thermal energy storage system as described above. In the specific implementation of the aforementioned power supply method for a photovoltaic thermal energy storage system, each module can be implemented as a processor.

[0300] The aforementioned readable storage medium can be implemented by any type of volatile or non-volatile storage device or a combination thereof, such as static random access memory (SRAM), electrically erasable programmable read-only memory (EEPROM), erasable programmable read-only memory (EPROM), programmable read-only memory (PROM), read-only memory (ROM), magnetic storage, flash memory, magnetic disk, or optical disk. The readable storage medium can be any available medium accessible to a general-purpose or special-purpose computer.

[0301] An exemplary readable storage medium is coupled to a processor, enabling the processor to read information from and write information to the readable storage medium. Of course, the readable storage medium can also be a component of the processor. The processor and the readable storage medium can reside in application-specific integrated circuits (ASICs). Alternatively, the processor and the readable storage medium can exist as discrete components in an electronic device or a host device.

[0302] This application also provides a computer program product, including a computer program, which, when executed by a processor, is used to implement a power supply method for a photovoltaic thermal energy storage system as described in the above embodiments.

[0303] The computer program is stored in a readable storage medium, and at least one processor can read the computer program from the readable storage medium and execute the computer program to perform the scheme provided in any of the above embodiments.

[0304] Those skilled in the art will understand that all or part of the steps of the above method embodiments can be implemented by hardware related to program instructions. The aforementioned program can be stored in a computer-readable storage medium. When the program is executed, it performs the steps of the above method embodiments; and the aforementioned storage medium includes various media capable of storing program code, such as ROM, RAM, magnetic disk, or optical disk.

[0305] The technical solutions of this application have been described above with reference to the preferred embodiments shown in the accompanying drawings. However, it is readily understood by those skilled in the art that the scope of protection of this application is obviously not limited to these specific embodiments. The above embodiments are only used to illustrate the technical solutions of this application and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. These modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. A power supply method for a photovoltaic thermal energy storage system, characterized in that, include: The state of charge (SOC) of various electrical energy and energy storage systems from multiple power sources and the inertia output capability of a shared bus capacitor are obtained; wherein, the inertia output capability is used to represent the ability of the shared bus capacitor to suppress voltage fluctuations across the shared bus capacitor. When the state of charge is higher than or equal to a preset state threshold and the inertia output capability is higher than or equal to a preset capability threshold, all the various electrical energies are injected into the shared bus capacitor, and the shared bus capacitor supplies power to the photovoltaic thermal energy storage system; wherein, the shared bus capacitor is electrically connected to the multiple power sources; When the state of charge is lower than the preset state threshold and the inertia output capability is lower than the preset capability threshold, the heat medium temperature of the photovoltaic thermal energy storage system, the thermal storage state of the preset thermal energy storage device, and the heat demand of the preset heat load are obtained, and an inertia compensation command is generated based on the heat medium temperature, the thermal storage state, and the heat demand; wherein, the inertia compensation command is used to adjust the operating state of the preset thermal side of the photovoltaic thermal energy storage system to provide compensation power for the shared bus capacitor; The various types of electrical energy and the compensation electrical energy are all injected into the shared bus capacitor, and the shared bus capacitor supplies power to the photovoltaic thermal energy storage system; wherein, the compensation electrical energy refers to the electrical energy released or converted by the preset thermal side after the inertia compensation command is executed, and the shared bus capacitor is electrically connected to the preset thermal side.

2. The power supply method for the photovoltaic thermal energy storage system according to claim 1, characterized in that, After injecting the various types of electrical energy and the compensation electrical energy into the shared bus capacitor, and supplying power to the photovoltaic thermal energy storage system through the shared bus capacitor, the method further includes: When the state of charge is lower than the preset state threshold and the inertia output capability is higher than the preset capability threshold, a pre-compensation command is generated based on the heat medium temperature, the heat storage state, and the heat demand. The pre-compensation command instructs the preset thermal side to reduce the operating power of the preset heat load when the state of charge is lower than the preset state threshold and the inertia output capability is higher than the preset capability threshold, so that the energy saved by the preset thermal side can be reserved for the shared bus capacitor. The preset heat load is set on the preset thermal side. When the state of charge is higher than the preset state threshold and the inertia output capability is lower than the preset capability threshold, an energy storage compensation command is generated based on the capability gap between the inertia output capability and the preset capability threshold; wherein, the energy storage compensation command is used to instruct the energy storage system to discharge to the shared bus capacitor with a power greater than the preset rated discharge power of the energy storage system.

3. The power supply method for the photovoltaic thermal energy storage system according to claim 2, characterized in that, The step of generating an energy storage compensation command based on the capacity gap between the inertia output capability and the preset capability threshold includes: Obtain the real-time voltage waveform of the shared bus capacitor, and extract the dynamic load characteristics of each electrical device in the photovoltaic thermal energy storage system from the real-time voltage waveform; Based on the dynamic load characteristics, identify the types of multiple electrical devices currently in operation in the solar thermal energy storage system and the instantaneous power demand curves corresponding to each electrical device, and retrieve the power supply priority of each electrical device from the preset device priority configuration table according to the type of each electrical device. Based on the instantaneous power demand curve, the capacity deficit, and the power supply priority of each electrical device, an energy storage compensation instruction is generated; wherein, the energy storage compensation instruction is used to instruct the energy storage system to discharge to the shared bus capacitor with a power greater than the preset rated discharge power, and to make the time-domain waveform of the discharge power preferentially match the instantaneous power demand curve of the electrical device with the highest power supply priority. According to the energy storage compensation command, the electrical energy output by the energy storage system is injected into the shared bus capacitor with a time-domain waveform that matches the instantaneous power demand curve of the electrical device with the highest power supply priority, so that when the shared bus capacitor discharges to each electrical device, the shared bus capacitor prioritizes ensuring the power demand of the electrical device with the highest power supply priority.

4. The power supply method for the photovoltaic thermal energy storage system according to claim 1, characterized in that, The multiple power sources include a photovoltaic system. The step of injecting all the various electrical energy sources into the shared bus capacitor and supplying power to the photovoltaic-thermal storage system through the shared bus capacitor includes: Based on the state of charge, the inertia output capability, and the real-time load power of the photovoltaic thermal energy storage system, a dynamic power allocation model is established on the power side; wherein, the dynamic power allocation model on the power side is used to determine the injection priority and power ratio of the multiple power supply sources to inject power into the shared bus capacitor; Based on the aforementioned dynamic power allocation model, a power allocation command is generated. This command is used to prioritize injecting the power output from the photovoltaic system into the shared bus capacitor when the voltage fluctuation rate of the shared bus capacitor is lower than a preset rate threshold, and to configure the energy storage system in a fast-response standby state so that the energy storage system immediately discharges when the voltage fluctuation rate of the shared bus capacitor increases. The power allocation command is also used to prioritize injecting the power output from the energy storage system into the shared bus capacitor when the voltage fluctuation rate of the shared bus capacitor is higher than the preset rate threshold, and to configure the photovoltaic system in a continuous power supply standby state so that the photovoltaic system continuously injects power when the voltage fluctuation rate of the shared bus capacitor decreases. According to the power allocation instruction, the various types of power are injected into the shared bus capacitor in batches according to the injection priority and the power allocation ratio.

5. The power supply method for the photovoltaic thermal energy storage system according to claim 4, characterized in that, The step of injecting the various types of electrical energy into the shared bus capacitor in batches according to the injection priority and the power allocation ratio based on the power allocation instruction includes: The real-time voltage value and voltage change trend of the shared bus capacitor are obtained, and a waveform shaping model is constructed based on the real-time voltage value and voltage change trend; wherein, the waveform shaping model is used to match the time-varying law of the injected power of the various electrical energies with the voltage fluctuation phase of the shared bus capacitor; Based on the various electrical energy sources and the waveform shaping model, a waveform shaping injection command is generated; wherein, the waveform shaping injection command is used to make the injected power decrease as the voltage increases when the voltage of the shared bus capacitor is in the rising phase, and to make the injected power increase as the voltage decreases when the voltage of the shared bus capacitor is in the falling phase. According to the waveform shaping injection command, the various electrical energies are injected into the shared bus capacitor in batches according to the injection priority and the power ratio, following the decreasing or increasing trend.

6. The power supply method for the photovoltaic thermal energy storage system according to claim 1, characterized in that, The step of injecting the various types of electrical energy and the compensation electrical energy into the shared bus capacitor, and supplying power to the photovoltaic thermal energy storage system through the shared bus capacitor, includes: The instantaneous phase feature and instantaneous amplitude feature of the real-time voltage waveform of the shared bus capacitor are obtained; wherein, the instantaneous phase feature is used to represent the phase angle of the real-time voltage waveform at the current moment, and the instantaneous amplitude feature is used to represent the amplitude of the real-time voltage waveform at the current moment; Based on the instantaneous phase characteristics and the instantaneous amplitude characteristics, the various electrical energies and the compensation electrical energy are subjected to power conversion to obtain an orthogonal injection current that is orthogonal to the phase of the real-time voltage waveform. The orthogonal injection current is then injected into the shared bus capacitor so that the orthogonal injection current absorbs electrical energy at the peak moment of the shared bus capacitor voltage and releases electrical energy at the zero-crossing moment of the shared bus capacitor voltage. Herein, the orthogonal injection current refers to the injection current that is phased with the real-time voltage waveform by a preset angle.

7. The power supply method for the photovoltaic thermal energy storage system according to claim 1, characterized in that, The capability to acquire the state of charge and inertia output of multiple power sources, energy storage systems, and shared bus capacitors from various power sources includes: The system acquires the various initial electrical energies output from the multiple power sources, the state of charge, and the inertia output capability. Differential preprocessing is performed on the various initial electrical energies to obtain the various electrical energies; wherein, the differential preprocessing is used to eliminate the differences between each electrical energy and the preset rated parameter requirements of the shared bus capacitor, so that the various electrical energies are adapted to the preset rated parameter requirements.

8. The power supply method for the photovoltaic thermal energy storage system according to claim 7, characterized in that, The multiple power sources include photovoltaic systems, energy storage systems, and the power grid. The differentiated preprocessing of these multiple initial electrical energies to obtain the various electrical energies includes: Obtain the bus voltage of the shared bus capacitor, the real-time maximum output power of the photovoltaic system, and the real-time power supply status of the power grid; Based on the bus voltage, the state of charge, the real-time maximum output power, and the real-time power supply status, a virtual inertia model of the photovoltaic thermal energy storage system is constructed; wherein, the virtual inertia model is used to establish the coupling relationship between the energy absorbed or released by the shared bus capacitor per unit time and the voltage fluctuation rate across the shared bus capacitor; Based on the virtual inertia model, the various initial electrical energies are preprocessed differently to obtain the various electrical energies.

9. The power supply method for the photovoltaic thermal energy storage system according to claim 8, characterized in that, The multiple initial electrical energies include a first electrical energy, a third electrical energy, and a fifth electrical energy; the multiple electrical energies also include a second electrical energy, a fourth electrical energy, and a sixth electrical energy; the differential preprocessing of the multiple initial electrical energies to obtain the multiple electrical energies includes: The first electrical energy is subjected to a maximum power point search to obtain the second electrical energy; wherein, the first electrical energy is the electrical energy output by the photovoltaic system; The third electrical energy is subjected to voltage matching and power regulation to obtain the fourth electrical energy; wherein, the third electrical energy is the electrical energy output by the energy storage system; The fifth electrical energy is converted from AC to DC and voltage matched to obtain the sixth electrical energy; wherein the fifth electrical energy is the electrical energy output by the power grid.

10. A power supply device for a photovoltaic thermal energy storage system, characterized in that, include: The first acquisition module is used to acquire the state of charge of various electrical energy and energy storage systems output from multiple power sources and the inertia output capability of the shared bus capacitor; wherein, the inertia output capability is used to represent the ability of the shared bus capacitor to suppress voltage fluctuations across the shared bus capacitor. The first injection module is used to inject the various electrical energies into the shared bus capacitor when the state of charge is higher than or equal to a preset state threshold and the inertia output capability is higher than or equal to a preset capability threshold, and to supply power to the photovoltaic thermal energy storage system through the shared bus capacitor; wherein, the shared bus capacitor is electrically connected to the multiple power sources; The second acquisition module is used to acquire the heat medium temperature of the photovoltaic thermal energy storage system, the thermal storage state of the preset thermal energy storage device, and the heat demand of the preset heat load when the state of charge is lower than the preset state threshold and the inertia output capability is lower than the preset capability threshold. Based on the heat medium temperature, the thermal storage state, and the heat demand, the module generates an inertia compensation command. The inertia compensation command is used to adjust the operating state of the preset thermal side of the photovoltaic thermal energy storage system to provide compensation power for the shared bus capacitor. The second injection module is used to inject the various types of electrical energy and the compensation electrical energy into the shared bus capacitor, and to supply power to the photovoltaic thermal energy storage system through the shared bus capacitor; wherein, the compensation electrical energy refers to the electrical energy released or converted by the preset thermal side after the inertia compensation command is executed, and the shared bus capacitor is electrically connected to the preset thermal side.

11. A power supply system for a photovoltaic thermal energy storage system, characterized in that, include: Multiple power sources, energy storage system, shared bus capacitor, control module and preset thermal side; The multiple power sources are used to output various types of electrical energy; The energy storage system is used to store electrical energy; The shared bus capacitor is electrically connected to the plurality of power sources and the energy storage system respectively. The shared bus capacitor is used to receive and store the electrical energy output by the plurality of power sources and to supply power to the photovoltaic thermal energy storage system. The shared bus capacitor has an inertia output capability, which is used to represent the ability of the shared bus capacitor to suppress voltage fluctuations across the shared bus capacitor. The control module is used to acquire the state of charge of the energy storage system, the inertia output capability of the shared bus capacitor, and when the state of charge is lower than a preset state threshold and the inertia output capability is lower than a preset capability threshold, acquire the heat medium temperature of the solar thermal energy storage system, the thermal storage state of the preset thermal storage device, and the heat demand of the preset heat load. The control module is further configured to, when the state of charge is higher than or equal to a preset state threshold and the inertia output capability is higher than or equal to a preset capability threshold, control the multiple power sources to inject various types of electrical energy into the shared bus capacitor; and when the state of charge is lower than the preset state threshold and the inertia output capability is lower than the preset capability threshold, generate an inertia compensation command based on the heat medium temperature, the heat storage state, and the heat demand; wherein, the inertia compensation command is used to adjust the operating state of the preset thermal side to provide compensation electrical energy for the shared bus capacitor; The preset thermal side is electrically connected to the shared bus capacitor and the control module. The preset thermal side is used to receive the inertia compensation command sent by the control module and respond to the inertia compensation command to adjust its own operating state, release or convert compensation energy, inject the compensation energy into the shared bus capacitor, and cooperate with the various electrical energy output by the multiple power sources to supply power to the photovoltaic thermal energy storage system through the shared bus capacitor.

12. A photovoltaic-thermal energy storage integrated power supply system, characterized in that, include: A preset thermal storage device, a preset heat load, a solar thermal storage system, and a power supply system for the solar thermal storage system as described in claim 11; The power supply system of the photovoltaic thermal energy storage system is electrically connected to the preset thermal energy storage device, the preset heat load, and the photovoltaic thermal energy storage system. The power supply system of the photovoltaic thermal energy storage system is used to obtain the thermal energy storage status of the preset thermal energy storage device and the heat demand of the preset heat load, and generate an inertia compensation command based on the thermal energy storage status and heat demand. The compensation power is supplied through the preset thermal side, and the power is supplied to the preset thermal energy storage device, the preset heat load, and the photovoltaic thermal energy storage system. The inertia compensation command is used to adjust the operating status of the preset thermal side to provide compensation power to the preset thermal energy storage device, the preset heat load, and the photovoltaic thermal energy storage system. The preset thermal storage device is used to store the thermal energy generated by the photovoltaic thermal storage system and to feed back the thermal storage status of the preset thermal storage device to the power supply system of the photovoltaic thermal storage system. The preset heat load is used to consume the heat energy generated by the photovoltaic thermal energy storage system, and the heat demand of the preset heat load is fed back to the power supply system of the photovoltaic thermal energy storage system.

13. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer-executable instructions, which, when executed by a processor, are used to implement the power supply method of the photovoltaic thermal energy storage system as described in any one of claims 1 to 9.

14. A computer program product, characterized in that, Includes a computer program, which, when executed by a processor, is used to implement the power supply method for the photovoltaic thermal energy storage system as described in any one of claims 1 to 9.

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