Control method of optical storage all-in-one machine system and optical storage all-in-one machine system

Abstract

The invention provides a control method of an optical storage all-in-one machine system and the optical storage all-in-one machine system, and relates to the field of optical storage all-in-one machine systems. The control method comprises the following steps of: stopping a direct current (DC) / alternating current (AC) converter of the optical storage all-in-one machine system under the conditions that a power grid is not powered off and power grid parameters are abnormal; and when the DC / AC converter is shut down and the power supply voltage of the photovoltaic cell panel of the optical storage all-in-one machine system does not meet the optimization condition, the energy storage DC / DC converter and the photovoltaic DC / DC converter of the optical storage all-in-one machine system are shut down.

Description

Technical Field

[0001] This disclosure relates to the field of integrated photovoltaic and energy storage systems, and more particularly to a control method for an integrated photovoltaic and energy storage system and an integrated photovoltaic and energy storage system. Background Technology

[0002] When a power outage occurs, the anti-islanding protection mechanism configured inside the photovoltaic-storage integrated system will detect changes in grid parameters in real time and trigger a cascading shutdown mechanism accordingly. At this time, all operating units will synchronously enter the shutdown state according to the preset safety logic, thereby ensuring the electrical isolation and operational safety of the system and effectively preventing the potential risks caused by the islanding effect.

[0003] However, under normal grid operation, voltage amplitude and frequency are not constant but are affected by various dynamic factors, such as sudden load switching, changes in line impedance, and fluctuations in distributed power sources. These disturbances can cause significant deviations in grid parameters within a short period. In this context, the inverter module, as the core control unit, will trigger a corresponding fault alarm mechanism and shut down if it detects that the voltage amplitude or frequency exceeds a set threshold. However, such fault response mechanisms are often localized, meaning they only shut down the inverter module itself, while other unaffected units may remain energized. This non-system-wide shutdown, while maintaining some system functionality, can also cause problems. For example, it can reduce overall system safety, posing safety hazards to maintenance personnel and surrounding equipment; it can also increase personal safety risks, as electric shock accidents can easily occur if it is not fully confirmed that all units are completely de-energized during system maintenance or repair. Summary of the Invention

[0004] One technical problem this disclosure aims to solve is to provide a control method and a photovoltaic-storage integrated system that can improve the overall operational safety and response capabilities of the system.

[0005] According to one aspect of this disclosure, a control method for a photovoltaic-storage integrated system is proposed, comprising: shutting down the DC / AC converter of the photovoltaic-storage integrated system when the power grid is not interrupted but the grid parameters are abnormal; and shutting down the energy storage DC / DC converter and the photovoltaic DC / DC converter of the photovoltaic-storage integrated system when the DC / AC converter shuts down and the power supply voltage of the photovoltaic panels of the photovoltaic-storage integrated system does not meet the optimization conditions.

[0006] In some embodiments, the DC / AC converter, the energy storage DC / DC converter, and the photovoltaic DC / DC converter are shut down sequentially through signal linkage.

[0007] In some embodiments, the DC / AC converter, the energy storage DC / DC converter, and the photovoltaic DC / DC converter are linked by signals to shut down sequentially, including: the DC / AC converter sending a first shutdown command to the energy storage DC / DC converter; the energy storage DC / DC converter detecting the first shutdown command and shutting down when it identifies that the supply voltage of the photovoltaic panel does not meet the optimization conditions, and sending a second shutdown command to the photovoltaic DC / DC converter; and the photovoltaic DC / DC converter shutting down when it detects the second shutdown command.

[0008] In some embodiments, the DC / AC converter includes a first digital signal processing (DSP) unit, a first level driving circuit, and a first digital output (DO) circuit. Sending a first shutdown command from the DC / AC converter to the energy storage DC / DC converter includes: the first DSP unit outputting a first level signal, the first level signal corresponding to the first shutdown command; the first level driving circuit amplifying the first level signal to a second level signal and sending the second level signal to the first DO circuit; and the first DO circuit converting the second level signal into a third level signal and sending it to the energy storage DC / DC converter.

[0009] In some embodiments, the energy storage DC / DC converter includes a first digital input (DI) unit, a second level driving circuit, and a second DSP unit. The energy storage DC / DC converter detects a first shutdown command by: the first DI unit receiving a signal sent by a DC / AC converter and sending the signal sent by the DC / AC converter to the second level driving circuit; the second level driving circuit reducing the signal sent by the DC / AC converter to a fourth level signal and sending the fourth level signal to the second DSP unit; and the second DSP unit identifying whether the signal sent by the DC / AC converter corresponds to the first shutdown command based on the fourth level signal.

[0010] In some embodiments, the energy storage DC / DC converter further includes a second DO circuit. The energy storage DC / DC converter sends a second shutdown command to the photovoltaic DC / DC converter by: the second DSP unit outputting a fifth-level signal, the fifth-level signal corresponding to the second shutdown command; the second-level drive circuit increasing the fifth-level signal to a sixth-level signal and sending the sixth-level signal to the second DO circuit; and the second DO circuit converting the sixth-level signal into a seventh-level signal and sending it to the photovoltaic DC / DC converter.

[0011] In some embodiments, the photovoltaic DC / DC converter includes a second DI unit, a third level drive circuit, and a third DSP unit. The photovoltaic DC / DC converter detects a second shutdown command by: the second DI unit receiving a signal sent by the energy storage DC / DC converter and sending the signal sent by the energy storage DC / DC converter to the third level drive circuit; the third level drive circuit reducing the signal sent by the energy storage DC / DC converter to an eighth level signal and sending the eighth level signal to the third DSP unit; and the third DSP unit identifying whether the signal sent by the energy storage DC / DC converter corresponds to the second shutdown command based on the eighth level signal.

[0012] In some embodiments, when the power supply voltage of the photovoltaic panels in the integrated photovoltaic and energy storage system meets the optimization conditions, the energy storage DC / DC converter and the photovoltaic DC / DC converter operate normally.

[0013] In some embodiments, if the grid parameters are normal, the DC / AC converter, energy storage DC / DC converter, and photovoltaic DC / DC converter are restarted when they are in a shutdown state.

[0014] According to another aspect of this disclosure, a photovoltaic-storage integrated system is also proposed, comprising: a DC / AC converter configured to shut down when the power grid is not interrupted but the grid parameters are abnormal; an energy storage DC / DC converter configured to shut down when the DC / AC converter shuts down and the supply voltage of the photovoltaic panels of the photovoltaic-storage integrated system does not meet the optimization conditions; and a photovoltaic DC / DC converter configured to shut down when the energy storage DC / DC converter shuts down.

[0015] In some embodiments, the DC / AC converter, the energy storage DC / DC converter, and the photovoltaic DC / DC converter are shut down sequentially through signal linkage.

[0016] In some embodiments, the DC / AC converter is configured to send a first shutdown command to the energy storage DC / DC converter; the energy storage DC / DC converter is configured to detect the first shutdown command and shut down when it identifies that the supply voltage of the photovoltaic panel does not meet the optimization conditions, and send a second shutdown command to the photovoltaic DC / DC converter; the photovoltaic DC / DC converter is configured to shut down when it detects the second shutdown command.

[0017] In some embodiments, the DC / AC converter includes: a first digital signal processing (DSP) unit configured to output a first level signal, the first level signal corresponding to a first stop command; a first level driving circuit configured to amplify the first level signal to a second level signal and send the second level signal to a first digital output (DO) circuit; and a first DO circuit configured to convert the second level signal into a third level signal and send it to an energy storage DC / DC converter.

[0018] In some embodiments, the energy storage DC / DC converter includes: a first digital input (DI) unit configured to receive a signal sent by a DC / AC converter and send the signal sent by the DC / AC converter to a second level driving circuit; a second level driving circuit configured to downgrade the signal sent by the DC / AC converter to a fourth level signal and send the fourth level signal to a second DSP unit; and a second DSP unit configured to identify whether the signal sent by the DC / AC converter corresponds to a first shutdown command based on the fourth level signal.

[0019] In some embodiments, the energy storage DC / DC converter further includes a second DO circuit, wherein the second DSP unit is configured to output a fifth-level signal, the fifth-level signal corresponding to a second shutdown command; the second-level drive circuit is configured to amplify the fifth-level signal to a sixth-level signal and send the sixth-level signal to the second DO circuit; the second DO circuit is configured to convert the sixth-level signal into a seventh-level signal and send it to the photovoltaic DC / DC converter.

[0020] In some embodiments, the photovoltaic DC / DC converter includes: a second DI unit configured to receive a signal sent by the energy storage DC / DC converter and send the signal sent by the energy storage DC / DC converter to a third level drive circuit; the third level drive circuit configured to downgrade the signal sent by the energy storage DC / DC converter to an eighth level signal and send the eighth level signal to a third DSP unit; and the third DSP unit configured to identify whether the signal sent by the energy storage DC / DC converter corresponds to a second shutdown command based on the eighth level signal.

[0021] In some embodiments, the energy storage DC / DC converter and the photovoltaic DC / DC converter are also configured to operate normally when the supply voltage of the photovoltaic panels in the integrated photovoltaic and energy storage system meets the optimization conditions.

[0022] In some embodiments, the DC / AC converter, the energy storage DC / DC converter, and the photovoltaic DC / DC converter are also configured to restart if the grid parameters are normal when in a shutdown state.

[0023] In this embodiment, under abnormal or fluctuating grid conditions, the DC / AC converter shuts down, and when the power supply voltage of the photovoltaic panel does not meet the optimization conditions, both the energy storage DC / DC converter and the photovoltaic DC / DC converter shut down. This ensures that the entire photovoltaic-energy storage system shuts down under abnormal or fluctuating grid conditions, thereby improving the overall operational safety and response capabilities of the system.

[0024] Other features and advantages of this disclosure will become clear from the following detailed description of exemplary embodiments with reference to the accompanying drawings. Attached Figure Description

[0025] The accompanying drawings, which form part of this specification, illustrate embodiments of this disclosure and, together with the specification, serve to explain the principles of this disclosure.

[0026] This disclosure will become clearer with reference to the accompanying drawings and the following detailed description, wherein:

[0027] Figure 1 Flowcharts illustrating some embodiments of the control method for the integrated photovoltaic and energy storage system disclosed herein;

[0028] Figure 2 Flowcharts illustrating other embodiments of the control method for the integrated photovoltaic and energy storage system disclosed herein;

[0029] Figure 3 Block diagrams of some embodiments of the DC / AC converter of this disclosure;

[0030] Figure 4 Block diagrams of some embodiments of the energy storage DC / DC converter disclosed herein;

[0031] Figure 5 Block diagrams of some embodiments of the photovoltaic DC / DC converter disclosed herein;

[0032] Figure 6 These are block diagrams of some embodiments of the integrated photovoltaic and energy storage system disclosed herein;

[0033] Figure 7 Block diagrams of other embodiments of the integrated photovoltaic and energy storage system disclosed herein. Detailed Implementation

[0034] Various exemplary embodiments of the present disclosure will now be described in detail with reference to the accompanying drawings. It should be noted that, unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps set forth in these embodiments do not limit the scope of the present disclosure.

[0035] At the same time, it should be understood that, for ease of description, the dimensions of the various parts shown in the accompanying drawings are not drawn according to actual scale.

[0036] The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit this disclosure or its application or use.

[0037] Techniques, methods, and equipment known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and equipment should be considered part of the specification.

[0038] In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values.

[0039] It should be noted that similar labels and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be discussed further in subsequent figures.

[0040] To make the objectives, technical solutions, and advantages of this disclosure clearer, the following detailed description is provided in conjunction with specific embodiments and the accompanying drawings.

[0041] In related technologies, under abnormal or fluctuating grid parameters, the DC / AC converter in a photovoltaic-storage integrated system triggers a corresponding fault alarm mechanism and shuts down the DC / AC converter. However, due to the localized nature of the fault triggering, the integrated photovoltaic-storage system cannot shut down all internal working units. Therefore, the working units that have not yet stopped may increase the safety risks to the system, surrounding equipment, or even maintenance personnel, easily causing electric shock accidents. This application provides a control method for a photovoltaic-storage integrated system, which can improve the overall operational safety performance and response capability of the system.

[0042] The solution disclosed herein will now be described in conjunction with specific embodiments.

[0043] like Figure 1 As shown, Figure 1 This is a flowchart illustrating some embodiments of the control method for the integrated photovoltaic and energy storage system disclosed herein, which includes steps S11-S12.

[0044] In step S11, if the power grid is not interrupted and the power grid parameters are abnormal, the DC (Direct Current) / AC (Alternating Current) converter of the photovoltaic-storage integrated system will be shut down.

[0045] A photovoltaic-storage integrated system is, for example, a user-specific photovoltaic-storage integrated system, specifically a stacked residential photovoltaic-storage integrated system. A stacked residential photovoltaic-storage integrated system is a modular energy device that deeply integrates photovoltaic power generation and energy storage systems. Through a "building block" stacking design, it achieves flexible capacity expansion, forming an intelligent closed-loop system of power generation, energy storage, and energy consumption.

[0046] In some embodiments, if the voltage amplitude or frequency fluctuates under normal grid operation, the DC / AC converter will report a fault and shut down.

[0047] For example, grid parameters are collected by a data acquisition module located on the grid side. These grid parameters can reflect the grid's operating status and determine whether the grid voltage amplitude or frequency is within the normal range. If it is within the normal range, the grid's operating status is monitored. If it is not within the normal range, the DC / AC converter reports a fault and shuts down.

[0048] In step S12, if the DC / AC converter stops and the power supply voltage of the photovoltaic panel of the photovoltaic-storage integrated system does not meet the optimization conditions, the energy storage DC / DC converter and the photovoltaic DC / DC converter of the photovoltaic-storage integrated system will stop.

[0049] Optimization criteria include, for example, that the photovoltaic (PV) panels can provide sufficient voltage to the integrated PV-storage system. Before the PV DC / DC converter and the energy storage DC / DC converter are shut down, the PV DC / DC converter can collect the supply voltage of the PV panels and send it to the energy storage DC / DC converter, so that the energy storage DC / DC converter can determine whether the supply voltage of the PV panels meets the optimization criteria.

[0050] In related technologies, when the grid parameters are abnormal, the entire process ends after the DC / AC unit shuts down. However, in this embodiment, if the power supply voltage of the photovoltaic panel does not meet the optimization conditions, both the energy storage DC / DC converter and the photovoltaic DC / DC converter will shut down. This allows the photovoltaic-storage integrated system to shut down completely under abnormal or fluctuating grid conditions, thereby improving the overall operational safety and response capabilities of the system.

[0051] In some embodiments, the DC / AC converter, the energy storage DC / DC converter, and the photovoltaic DC / DC converter are shut down sequentially through signal linkage.

[0052] For example, after the DC / AC converter shuts down, the energy storage DC / DC converter shuts down via signal linkage. Similarly, after the energy storage DC / DC converter shuts down, the photovoltaic DC / DC converter also shuts down via signal linkage.

[0053] In this embodiment, through signal linkage between the various converters, the DC / AC converter can detect that the grid connected to the system is in an abnormal or fluctuating state, shut down the DC / AC converter, and link signals with the energy storage DC / DC converter and the photovoltaic DC / DC converter to also shut down the energy storage DC / DC converter and the photovoltaic DC / DC converter. This improves the overall operational safety performance of the system, thereby achieving more efficient and reliable safety protection. Furthermore, since the DC / AC converter, energy storage DC / DC converter and photovoltaic DC / DC converter shut down sequentially and in a unidirectional manner, the number of communication links can be reduced, thereby reducing hardware costs.

[0054] In some embodiments, the DC / AC converter, the energy storage DC / DC converter, and the photovoltaic DC / DC converter are linked by signals to shut down sequentially, including: the DC / AC converter sending a first shutdown command to the energy storage DC / DC converter; the energy storage DC / DC converter detecting the first shutdown command and shutting down when it identifies that the supply voltage of the photovoltaic panel does not meet the optimization conditions, and sending a second shutdown command to the photovoltaic DC / DC converter; and the photovoltaic DC / DC converter shutting down when it detects the second shutdown command.

[0055] For example, when the grid voltage amplitude or frequency is outside the normal range, the DC / AC converter shuts down and sets its shutdown flag to 1. The DC / AC converter then sends the shutdown flag to the energy storage DC / DC converter. The energy storage DC / DC converter checks if the received shutdown flag is set to 1. If it is, it continues to check if the supply voltage of the photovoltaic panel meets the optimization conditions. If so, it shuts down, sets its own shutdown flag to 1, and sends the shutdown flag to the photovoltaic DC / DC converter. The photovoltaic DC / DC converter then checks if the received shutdown flag is set to 1. If it is, it shuts down.

[0056] If the DC / AC converter stops, it sends a stop flag to both the energy storage DC / DC converter and the photovoltaic DC / DC converter. However, whether the photovoltaic DC / DC converter stops requires information about the energy storage DC / DC converter's status; otherwise, the system cannot determine whether the photovoltaic power supply to the energy storage converter can operate. Therefore, three communication links are needed, which undoubtedly increases hardware costs. In the above embodiment, the DC / AC converter, energy storage DC / DC converter, and photovoltaic DC / DC converter sequentially determine whether a stop is needed through signal linkage. Only two communication links are required to achieve the necessary functions and guarantees, improving the overall system's operational safety and reducing power consumption.

[0057] In some embodiments, when the power supply voltage of the photovoltaic panels in the integrated photovoltaic and energy storage system meets the optimization conditions, the energy storage DC / DC converter and the photovoltaic DC / DC converter operate normally.

[0058] If the supply voltage of the photovoltaic panel meets the optimization condition, it means that the photovoltaic equipment connected to the photovoltaic DC / DC converter can supply power to the energy storage battery or other user electrical equipment connected to the energy storage DC / DC converter. Therefore, the working mode of the photovoltaic panel charging the energy storage battery can operate normally.

[0059] The control method of the integrated photovoltaic and energy storage system disclosed herein will be further described below using a specific embodiment as an example.

[0060] like Figure 2 As shown, Figure 2 This is a flowchart illustrating another embodiment of the control method for the integrated photovoltaic and energy storage system disclosed herein, which includes steps S21-S212.

[0061] In step S21, the power grid operating status is detected.

[0062] For example, a data acquisition module can be installed on the power grid side to collect the power grid's parameter status.

[0063] In step S22, it is determined whether the voltage amplitude or frequency of the power grid is within the normal range. If so, step S21 is executed; otherwise, step S23 is executed.

[0064] If the voltage amplitude or frequency of the power grid is within the normal range, the system continues to monitor the operating status of the power grid parameters. If it is not within the normal range, the power grid can be considered to be in an abnormal or fluctuating state.

[0065] In step S23, the DC / AC converter reports a fault.

[0066] In step S24, the DC / AC converter is shut down.

[0067] In step S25, the DC / AC converter sets the shutdown flag to 1 and sends it to the energy storage DC / DC converter.

[0068] In step S26, the energy storage DC / DC converter determines whether the stop flag bit of the DC / AC converter is set to 1. If so, step S27 is executed; otherwise, the energy storage DC / DC converter continues to operate.

[0069] In step S27, the energy storage DC / DC converter determines whether the power supply voltage of the photovoltaic panel meets the optimization condition. If so, step S28 is executed; otherwise, step S29 is executed.

[0070] In step S28, the photovoltaic DC / DC converter and the energy storage DC / DC converter operate normally. This ensures that the photovoltaic panel charging the energy storage battery mode operates normally.

[0071] In step S29, the energy storage DC / DC converter is shut down.

[0072] In step S210, the energy storage DC / DC converter sets the shutdown flag to 1 and sends it to the photovoltaic DC / DC converter.

[0073] In step S211, the photovoltaic DC / DC converter determines whether the shutdown flag of the energy storage DC / DC converter is set to 1. If yes, step S212 is executed; otherwise, operation continues.

[0074] In step S212, the photovoltaic DC / DC converter is shut down.

[0075] In the above embodiment, the DC / AC converter sends a shutdown flag to the energy storage DC / DC converter, and the energy storage DC / DC converter sends a shutdown flag to the photovoltaic DC / DC converter. This signal linkage ensures that the energy storage DC / DC converter responds to the DC / AC converter's commands when shutting down, and the photovoltaic DC / DC converter responds to the energy storage DC / DC converter's commands when shutting down, establishing a hierarchical relationship between the converters. This embodiment improves the overall system's operational safety and resilience, enhances the system's internal inter-unit fault tolerance mechanisms and collaborative control capabilities, mitigates losses, and achieves more efficient and reliable safety protection.

[0076] In some embodiments, the signal linkage between the DC / AC converter, the energy storage DC / DC converter, and the photovoltaic DC / DC converter is achieved through the internal hardware circuitry of each converter.

[0077] like Figure 3 As shown, Figure 3 The block diagram is for some embodiments of the DC / AC converter disclosed herein. The DC / AC converter 3 includes a first DSP (Digital Signal Processing) unit 31, a first level driving circuit 32, and a first DO (Digital Output) circuit 33.

[0078] The first DSP unit 31 outputs a first level signal, which corresponds to a first stop command; the first level drive circuit 32 increases the first level signal to a second level signal and sends the second level signal to the first DO circuit 33; the first DO circuit 33 converts the second level signal into a third level signal and sends it to the energy storage DC / DC converter.

[0079] Level-driven circuits can increase the driving capability of signals.

[0080] For example, after the DC / AC converter stops, the stop flag is set to 1. The high-level signal emitted by the first DSP unit 31 is 3.3V. After passing through the first level drive circuit 32, the driving capability of the signal is increased, making the high-level signal, for example, 5V. Then, after passing through the first DO circuit 33, a 24V control signal is output to the first DI (Digital Input) circuit of the energy storage DC / AC converter, enabling the energy storage DC / AC converter to identify the state of the DC / AC converter. If the DC / AC converter does not set the stop flag to 1, the first DSP unit 31 outputs a low-level signal. Subsequently, the energy storage DC / AC converter confirms that the DC / AC converter has not stopped and will not perform subsequent operations.

[0081] In this embodiment, the transmission and reception between the DC / AC converter and the energy storage DC / DC converter are implemented through hardware design. For example, signal transmission can be achieved through the physical characteristics of circuit elements. Compared with software methods, this reduces data latency and vulnerability to attacks, and improves key engineering indicators such as real-time performance, reliability, and power efficiency. It is especially suitable for scenarios with stringent requirements for stability, response speed, and environmental adaptability.

[0082] In some embodiments, such as Figure 4 As shown, Figure 4 This is a block diagram of some embodiments of the energy storage DC / DC converter disclosed herein. The energy storage DC / DC converter 4 includes a first DI unit 41, a second level drive circuit 42, and a second DSP unit 43.

[0083] The first DI unit 41 receives the signal sent by the DC / AC converter and sends the signal sent by the DC / AC converter to the second level driving circuit 42; the second level driving circuit 42 reduces the signal sent by the DC / AC converter to a fourth level signal and sends the fourth level signal to the second DSP unit 43; the second DSP unit 43 identifies whether the signal sent by the DC / AC converter corresponds to the first stop command based on the fourth level signal.

[0084] For example, the first DI unit 41 receives the third-level signal output from the first DO circuit 33 of the DC / AC converter and inputs the third-level signal to the second-level drive circuit 42, such as sending a 24V control signal to the second-level drive circuit 42. The second-level drive circuit 42 reduces the driving capability of the 24V control signal and then inputs the signal to the second DSP unit 43. If the signal is identified as a high-level signal, the DC / AC converter is considered to be in a shutdown state.

[0085] In this embodiment, the process of the DC / AC converter sending signals to the energy storage DC / DC converter and the energy storage DC / DC converter identifying the state of the DC / AC converter is unidirectional, thereby reducing energy consumption and improving the reliability of signal transmission.

[0086] In some embodiments, the energy storage DC / DC converter further includes a second DO circuit 44, wherein the second DSP unit 41 outputs a fifth-level signal, which corresponds to a second shutdown command; the second-level drive circuit 42 amplifies the fifth-level signal to a sixth-level signal and sends the sixth-level signal to the second DO circuit 44; the second DO circuit 44 converts the sixth-level signal into a seventh-level signal and sends it to the photovoltaic DC / DC converter.

[0087] For example, after the energy storage DC / AC is shut down, the shutdown flag is set to 1, and the high-level signal sent by the second DSP unit 41 is 3.3V. After passing through the second level drive circuit 42, the driving capability of the signal is increased, so that the high-level signal is, for example, 5V. Then, through the second DO circuit 44, a 24V control signal is output to the second DI circuit of the photovoltaic DC / DC converter, so that the photovoltaic DC / DC converter can identify the status of the energy storage DC / DC converter.

[0088] In this embodiment, the transmission and reception between the energy storage DC / DC converter and the photovoltaic DC / DC converter are implemented through hardware design. For example, signal transmission can be achieved through the physical characteristics of circuit elements. Compared with software methods, this reduces data latency and vulnerability to attacks, and improves key engineering indicators such as real-time performance, reliability, and power efficiency. It is especially suitable for scenarios with stringent requirements for stability, response speed, and environmental adaptability.

[0089] In some embodiments, such as Figure 5 As shown, Figure 5 This is a block diagram of some embodiments of the photovoltaic DC / DC converter 5 disclosed herein, which includes a second DI unit 51, a third level drive circuit 52, and a third DSP unit 53.

[0090] The second DI unit 51 receives the signal sent by the energy storage DC / DC converter and sends the signal sent by the energy storage DC / DC converter to the third level drive circuit 52; the third level drive circuit 52 reduces the signal sent by the energy storage DC / DC converter to the eighth level signal and sends the eighth level signal to the third DSP unit 53; the third DSP unit 53 identifies whether the signal sent by the energy storage DC / DC converter corresponds to the second stop command based on the eighth level signal.

[0091] For example, the second DI unit 51 receives the seventh-level signal output from the second DO circuit 44 of the energy storage DC / DC converter and inputs the seventh-level signal to the third-level drive circuit 52, such as sending a 24V control signal to the third-level drive circuit 52. The third-level drive circuit 52 reduces the driving capability of the 24V control signal and then inputs the signal to the third DSP unit 53. If the signal is identified as a high-level signal, it is considered that the energy storage DC / AC converter is in a shutdown state. At this time, the photovoltaic DC / DC converter is shut down.

[0092] In this embodiment, the energy storage DC / DC converter sending signals to the photovoltaic DC / DC converter and the photovoltaic DC / DC converter identifying the state of the energy storage DC / DC converter are unidirectional, thereby reducing energy consumption and improving the reliability of signal transmission.

[0093] In some embodiments, if the grid parameters are normal, the DC / AC converter, energy storage DC / DC converter, and photovoltaic DC / DC converter are restarted when they are in a shutdown state.

[0094] In this embodiment, if the DC / AC converter, the energy storage DC / DC converter, and the photovoltaic DC / DC converter are all shut down, the system restart action is determined based on the grid parameter status to facilitate the timely restoration of the normal operation of the photovoltaic-energy storage integrated system.

[0095] The above describes the control method of the integrated photovoltaic and energy storage system disclosed herein. The integrated photovoltaic and energy storage system of this disclosure will be further described below with reference to the accompanying drawings.

[0096] like Figure 6 As shown, Figure 6 This is a block diagram of some embodiments of the photovoltaic-storage integrated system disclosed herein, which includes a DC / AC converter 3, an energy storage DC / DC converter 4, and a photovoltaic DC / DC converter 5.

[0097] DC / AC converter 3 is configured to shut down when the power grid is not interrupted but the grid parameters are abnormal.

[0098] The energy storage DC / DC converter 4 is configured to shut down when the DC / AC converter is shut down and the supply voltage of the photovoltaic panels in the integrated photovoltaic and energy storage system does not meet the optimization conditions.

[0099] The photovoltaic DC / DC converter 5 is configured to shut down in the event that the energy storage DC / DC converter is shut down.

[0100] In this embodiment, when the grid parameters are abnormal, the DC / AC unit shuts down, and the power supply voltage of the photovoltaic panel does not meet the optimization conditions. In this case, the energy storage DC / DC converter and the photovoltaic DC / DC converter also shut down, so that the photovoltaic-storage integrated system shuts down completely under abnormal or fluctuating grid conditions, thereby improving the overall operational safety performance and response capability of the system.

[0101] In some embodiments, the DC / AC converter, the energy storage DC / DC converter, and the photovoltaic DC / DC converter are shut down sequentially through signal linkage.

[0102] In this embodiment, through signal linkage between various converters, the DC / AC converter can detect that the grid connected to the system is in an abnormal or fluctuating state, shut down the DC / AC converter, and link signals with the energy storage DC / DC converter and the photovoltaic DC / DC converter to make the energy storage DC / DC converter and the photovoltaic DC / DC converter also shut down, thereby improving the overall operational safety performance of the system and achieving more efficient and reliable safety protection.

[0103] In some embodiments, the DC / AC converter 3 is configured to send a first shutdown command to the energy storage DC / DC converter; the energy storage DC / DC converter 4 is configured to detect the first shutdown command and shut down when it identifies that the supply voltage of the photovoltaic panel does not meet the optimization conditions, and send a second shutdown command to the photovoltaic DC / DC converter; the photovoltaic DC / DC converter 5 is configured to shut down when it detects the second shutdown command.

[0104] In the above embodiments, the DC / AC converter, the energy storage DC / DC converter, and the photovoltaic DC / DC converter are sequentially linked by signals to determine whether a shutdown is required. Only two communication links are needed to achieve the required functions and guarantees, thereby improving the overall operational safety performance of the system and reducing the system's power consumption.

[0105] In some embodiments, the energy storage DC / DC converter and the photovoltaic DC / DC converter are further configured to operate normally when the supply voltage of the photovoltaic panel in the integrated photovoltaic-energy storage system meets the optimization conditions. This allows the photovoltaic panel to charge the energy storage battery in normal operation.

[0106] In some embodiments, the DC / AC converter, the energy storage DC / DC converter, and the photovoltaic DC / DC converter are also configured to restart if the grid parameters are normal when in a shutdown state.

[0107] In some embodiments, such as Figure 3As shown, the DC / AC converter 3 includes a first DSP unit 31, a first level drive circuit 32, and a first DO (Digital Output) circuit 33.

[0108] The first DSP unit 31 is configured to output a first level signal, which corresponds to a first stop command; the first level drive circuit 32 is configured to amplify the first level signal to a second level signal and send the second level signal to the first DO circuit 33; the first DO circuit 33 is configured to convert the second level signal into a third level signal and send it to the energy storage DC / DC converter.

[0109] In some embodiments, such as Figure 4 As shown, the energy storage DC / DC converter 4 includes a first DI unit 41, a second level drive circuit 42, and a second DSP unit 43.

[0110] The first DI unit 41 is configured to receive the signal sent by the DC / AC converter and send the signal sent by the DC / AC converter to the second level driving circuit 42; the second level driving circuit 42 is configured to reduce the signal sent by the DC / AC converter to a fourth level signal and send the fourth level signal to the second DSP unit 43; the second DSP unit 43 is configured to identify whether the signal sent by the DC / AC converter corresponds to the first stop command based on the fourth level signal.

[0111] In some embodiments, the energy storage DC / DC converter further includes a second DO circuit 44, wherein the second DSP unit 41 is configured to output a fifth-level signal, the fifth-level signal corresponding to a second shutdown command; the second-level drive circuit 42 is configured to amplify the fifth-level signal to a sixth-level signal and send the sixth-level signal to the second DO circuit 44; the second DO circuit 44 is configured to convert the sixth-level signal into a seventh-level signal and send it to the photovoltaic DC / DC converter.

[0112] In some embodiments, such as Figure 5 As shown, the photovoltaic DC / DC converter 5 includes a second DI unit 51, a third level drive circuit 52, and a third DSP unit 53.

[0113] The second DI unit 51 is configured to receive the signal sent by the energy storage DC / DC converter and send the signal sent by the energy storage DC / DC converter to the third level drive circuit 52; the third level drive circuit 52 is configured to reduce the signal sent by the energy storage DC / DC converter to an eighth level signal and send the eighth level signal to the third DSP unit 53; the third DSP unit 53 is configured to identify whether the signal sent by the energy storage DC / DC converter corresponds to the second stop command based on the eighth level signal.

[0114] Figure 7 This is a block diagram of some other embodiments of the photovoltaic-storage integrated system disclosed herein. In addition to a DC / AC converter 3, an energy storage DC / DC converter 4, and a photovoltaic DC / DC converter 5, the DC / AC converter 3 is connected to the power grid 6 and an AC load 7. A data acquisition module 8 can also be installed on the power grid side to acquire the amplitude and frequency of the power grid voltage. The energy storage DC / DC converter 4 is connected to the energy storage battery BAT, the photovoltaic DC / DC converter 5 is connected to the photovoltaic circuit breaker RLY, and the photovoltaic circuit breaker RLY is connected to the photovoltaic panel 9.

[0115] The DC / AC converter 3, energy storage DC / DC converter 4, and photovoltaic DC / DC converter 5 use signal linkage to determine whether to shut down or start up. This ensures that the system's overall operational safety and response capabilities are improved under abnormal or fluctuating grid conditions, enhances the fault tolerance mechanism and collaborative control capabilities between units within the system, and mitigates losses, thereby achieving more efficient and reliable safety protection.

[0116] This concludes the detailed description of the present disclosure. To avoid obscuring the concept of the disclosure, some details known in the art have not been described. Those skilled in the art will fully understand how to implement the technical solutions disclosed herein based on the above description.

[0117] The methods and apparatus of this disclosure may be implemented in many ways. For example, they may be implemented by software, hardware, firmware, or any combination of software, hardware, and firmware. The above-described order of steps for the methods is for illustrative purposes only, and the steps of the methods of this disclosure are not limited to the order specifically described above unless otherwise specifically stated. Furthermore, in some embodiments, this disclosure may also be implemented as a program recorded on a recording medium, the program including machine-readable instructions for implementing the methods according to this disclosure. Thus, this disclosure also covers recording media storing programs for performing the methods according to this disclosure.

[0118] While specific embodiments of this disclosure have been described in detail by way of example, those skilled in the art should understand that the examples are for illustrative purposes only and not intended to limit the scope of this disclosure. Those skilled in the art should understand that modifications can be made to the above embodiments without departing from the scope and spirit of this disclosure. The scope of this disclosure is defined by the appended claims.

Claims

1. A control method for a photovoltaic-storage integrated system, comprising: If the power grid is not interrupted but the power grid parameters are abnormal, the DC / AC converter of the photovoltaic-storage integrated system will shut down. When the DC / AC converter shuts down and the power supply voltage of the photovoltaic panels in the integrated photovoltaic and energy storage system does not meet the optimization conditions, the energy storage DC / DC converter and the photovoltaic DC / DC converter of the integrated photovoltaic and energy storage system shall shut down.

2. The control method according to claim 1, wherein, The DC / AC converter, the energy storage DC / DC converter, and the photovoltaic DC / DC converter are linked by signals and shut down sequentially.

3. The control method according to claim 2, wherein, The DC / AC converter, the energy storage DC / DC converter, and the photovoltaic DC / DC converter are linked by signals and sequentially shut down, including: The DC / AC converter sends a first shutdown command to the energy storage DC / DC converter; The energy storage DC / DC converter detects the first shutdown command and identifies that the power supply voltage of the photovoltaic panel does not meet the optimization conditions, and then shuts down, and sends a second shutdown command to the photovoltaic DC / DC converter. The photovoltaic DC / DC converter shuts down upon detecting the second shutdown command.

4. The control method according to claim 3, wherein, The DC / AC converter includes a first digital signal processing (DSP) unit, a first level driving circuit, and a first digital output (DO) circuit. The DC / AC converter sending a first shutdown command to the energy storage DC / AC converter includes: The first DSP unit outputs a first level signal, which corresponds to the first stop command; The first level driving circuit amplifies the first level signal to a second level signal and sends the second level signal to the first DO circuit; The first DO circuit converts the second level signal into a third level signal and then sends it to the energy storage DC / DC converter.

5. The control method according to claim 3, wherein, The energy storage DC / DC converter includes a first digital input (DI) unit, a second level drive circuit, and a second DSP unit. The energy storage DC / DC converter detects the first shutdown command by: The first DI unit receives the signal sent by the DC / AC converter and sends the signal sent by the DC / AC converter to the second level driving circuit; The second level driving circuit reduces the signal sent by the DC / AC converter to a fourth level signal and sends the fourth level signal to the second DSP unit; The second DSP unit identifies whether the signal sent by the DC / AC converter corresponds to the first shutdown command based on the fourth level signal.

6. The control method according to claim 5, wherein, The energy storage DC / DC converter further includes a second DO circuit, and the energy storage DC / DC converter sends a second shutdown command to the photovoltaic DC / DC converter, including: The second DSP unit outputs a fifth-level signal, which corresponds to the second stop command; The second level driving circuit amplifies the fifth level signal to a sixth level signal and sends the sixth level signal to the second DO circuit; The second DO circuit converts the sixth-level signal into a seventh-level signal and then sends it to the photovoltaic DC / DC converter.

7. The control method according to claim 3, wherein, The photovoltaic DC / DC converter includes a second DI unit, a third level drive circuit, and a third DSP unit. The photovoltaic DC / DC converter detects the second shutdown command by: The second DI unit receives the signal sent by the energy storage DC / DC converter and sends the signal sent by the energy storage DC / DC converter to the third level drive circuit; The third-level driving circuit reduces the signal sent by the energy storage DC / DC converter to an eighth-level signal, and sends the eighth-level signal to the third DSP unit; The third DSP unit identifies, based on the eighth level signal, whether the signal sent by the energy storage DC / DC converter corresponds to the second shutdown command.

8. The control method according to any one of claims 1 to 7, further comprising: When the power supply voltage of the photovoltaic panels in the integrated photovoltaic and energy storage system meets the optimization conditions, the energy storage DC / DC converter and the photovoltaic DC / DC converter operate normally.

9. The control method according to any one of claims 1 to 7, further comprising: If the power grid parameters are normal while the DC / AC converter, the energy storage DC / DC converter, and the photovoltaic DC / DC converter are in a shutdown state, then the DC / AC converter, the energy storage DC / DC converter, and the photovoltaic DC / DC converter shall be restarted.

10. A photovoltaic-storage integrated system, comprising: The DC / AC converter is configured to shut down when the power grid is not interrupted but the grid parameters are abnormal. The energy storage DC / DC converter is configured to shut down when the DC / AC converter stops and the supply voltage of the photovoltaic panels of the integrated photovoltaic and energy storage system does not meet the optimization conditions. The photovoltaic DC / DC converter is configured to shut down in the event that the energy storage DC / DC converter is shut down.

11. The integrated photovoltaic and energy storage system according to claim 10, wherein, The DC / AC converter, the energy storage DC / DC converter, and the photovoltaic DC / DC converter are linked by signals and shut down sequentially.

12. The integrated photovoltaic and energy storage system according to claim 11, wherein, The DC / AC converter is configured to send a first shutdown command to the energy storage DC / DC converter; The energy storage DC / DC converter is configured to detect the first shutdown command and shut down when it identifies that the power supply voltage of the photovoltaic panel does not meet the optimization conditions, and send a second shutdown command to the photovoltaic DC / DC converter. The photovoltaic DC / DC converter is configured to shut down upon detecting the second shutdown command.

13. The integrated photovoltaic and energy storage system according to claim 12, wherein, The DC / AC converter includes: A first digital signal processing (DSP) unit is configured to output a first level signal, the first level signal corresponding to the first stop command; The first level driving circuit is configured to amplify the first level signal to a second level signal and send the second level signal to the first digital output (DO) circuit. The first DO circuit is configured to convert the second level signal into a third level signal and then send it to the energy storage DC / DC converter.

14. The integrated photovoltaic and energy storage system according to claim 12, wherein, The energy storage DC / DC converter includes: The first digital input (DI) unit is configured to receive the signal sent by the DC / AC converter and send the signal sent by the DC / AC converter to the second level driving circuit. The second level driving circuit is configured to reduce the signal sent by the DC / AC converter to a fourth level signal and send the fourth level signal to the second DSP unit; The second DSP unit is configured to identify, based on the fourth level signal, whether the signal sent by the DC / AC converter corresponds to the first stop command.

15. The integrated photovoltaic and energy storage system according to claim 14, wherein, The energy storage DC / DC converter also includes a second DO circuit, wherein, The second DSP unit is configured to output a fifth-level signal, which corresponds to the second stop command; The second level driving circuit is configured to amplify the fifth level signal to a sixth level signal and send the sixth level signal to the second DO circuit; The second DO circuit is configured to convert the sixth-level signal into a seventh-level signal and then send it to the photovoltaic DC / DC converter.

16. The integrated photovoltaic and energy storage system according to claim 12, wherein, The photovoltaic DC / DC converter includes: The second DI unit is configured to receive the signal sent by the energy storage DC / DC converter and send the signal sent by the energy storage DC / DC converter to the third level drive circuit; The third-level driving circuit is configured to reduce the signal sent by the energy storage DC / DC converter to an eighth-level signal and send the eighth-level signal to the third DSP unit; The third DSP unit is configured to identify, based on the eighth level signal, whether the signal sent by the energy storage DC / DC converter corresponds to the second shutdown command.

17. The integrated photovoltaic and energy storage system according to any one of claims 10 to 16, wherein, The energy storage DC / DC converter and the photovoltaic DC / DC converter are also configured to operate normally when the power supply voltage of the photovoltaic panel in the integrated photovoltaic and energy storage system meets the optimization conditions.

18. The integrated photovoltaic and energy storage system according to any one of claims 10 to 16, wherein, The DC / AC converter, the energy storage DC / DC converter, and the photovoltaic DC / DC converter are also configured to restart if the grid parameters are normal when in a shutdown state.

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