A fuel-photovoltaic hybrid power supply system and control method

Abstract

The present disclosure relates to a fuel-photovoltaic hybrid power supply system and a control method, and belongs to the field of photovoltaic power generation technology. The fuel-photovoltaic hybrid power supply system includes: a photovoltaic power generation module, an energy storage module, a fuel generator module, an energy conversion module and a control module. The present disclosure also relates to a control method for the above-mentioned fuel-photovoltaic hybrid power supply system, and the control method includes: when it is monitored that the load parameters of the load and the power generation parameters of the photovoltaic power generation module meet the first condition, determining the working parameters of the fuel generator module based on the power generation parameters of the photovoltaic power generation module; and controlling the fuel generator module to supply power to the load through the energy conversion module based on the working parameters of the fuel generator module. The present disclosure can improve the power supply stability of the system when the load increases.

Description

Technical Field

[0001] The present disclosure relates to the technical field of photovoltaic power generation, and in particular to a fuel-photovoltaic hybrid power supply system and a control method. Background Art

[0002] Photovoltaic power generation is a technology that uses the photovoltaic effect of semiconductor interfaces to directly convert light energy into electrical energy. Since the energy conversion efficiency of the photovoltaic effect is low, only 10%-20% conversion efficiency, larger solar photovoltaic panels are usually required to collect solar energy. In addition, solar tracking technology is also widely used in the field of photovoltaic power generation to maximize the collection of solar energy. Even so, the energy obtained is still significantly affected by meteorological conditions such as seasons, day and night, and cloudy and sunny weather.

[0003] For the above reasons, people began to explore the combination of photovoltaic power generation with other forms of energy to build a more stable and efficient power supply system. The fuel-photovoltaic hybrid power supply system is one of the important attempts. It combines the clean and renewable characteristics of photovoltaic power generation with the stable and reliable characteristics of fuel power generation, aiming to achieve optimal configuration and efficient utilization of energy. At present, the fuel-photovoltaic hybrid power supply system has been initially applied in some remote areas, islands or areas with unstable power grids. However, when the load power continues to grow, the existing fuel-photovoltaic hybrid power supply system often finds it difficult to achieve a stable energy supply. Summary of the invention

[0004] To solve the above problems, the embodiments of the present disclosure provide a fuel-photovoltaic hybrid power supply system and a control method to solve the problem of unstable power supply of the fuel-photovoltaic hybrid power supply system when the load increases in the prior art.

[0005] According to a first aspect of the present disclosure, a control method for a fuel-photovoltaic hybrid power supply system is provided, which is applied to the fuel-photovoltaic hybrid power supply system.

[0006] The fuel-photovoltaic hybrid power supply system includes a photovoltaic power generation module, an energy storage module, a fuel generator module, an energy conversion module and a control module;

[0007] The control method comprises: when it is monitored that the load parameter of the load and the power generation parameter of the photovoltaic power generation module meet a first condition, determining the working parameter of the fuel generator module based on the power generation parameter of the photovoltaic power generation module;

[0008] Based on the working parameters of the fuel generator module, the fuel generator module is controlled to supply power to the load through the energy conversion module;

[0009] The load parameters of the load include the power change of the load, and the power generation parameters of the photovoltaic power generation module include the power generation power of the photovoltaic power generation module; the first condition is: the power change of the load is greater than the first threshold, and the power generation power of the photovoltaic power generation module is less than the first power threshold.

[0010] In an exemplary embodiment of the present disclosure, the control method is also used for:

[0011] When it is monitored that the load parameters of the load and the power generation parameters of the photovoltaic power generation module meet the second condition, determining the working parameters of the energy storage module, and controlling the energy storage module to supply power to the load through the energy conversion module based on the working parameters of the energy storage module;

[0012] The second condition is that: the power change of the load is less than or equal to a first threshold, and the power generation power of the photovoltaic power generation module is less than the first power threshold.

[0013] In an exemplary embodiment of the present disclosure, the power generation parameters of the photovoltaic power generation module further include the illumination intensity and output power of the photovoltaic power generation module, and the working parameters of the fuel generator module further include the pre-start time of the fuel generator module;

[0014] The step of determining the operating parameters of the fuel generator module based on the power generation parameters of the photovoltaic power generation module includes:

[0015] The pre-start time of the fuel generator module is determined based on the light intensity and output power of the photovoltaic power generation module and the environmental characteristics of the photovoltaic power generation module.

[0016] In an exemplary embodiment of the present disclosure, the power generation parameters of the photovoltaic power generation module also include the output frequency of the photovoltaic power generation module; the operating parameters of the fuel generator module also include the output frequency of the fuel generator module;

[0017] The step of determining the operating parameters of the fuel generator module based on the power generation parameters of the photovoltaic power generation module includes:

[0018] The phase of the output voltage of the fuel generator module is determined based on the output voltage of the photovoltaic power generation module.

[0019] In an exemplary embodiment of the present disclosure, the control method further includes:

[0020] When it is monitored that the load parameter of the load and the power generation parameter of the photovoltaic power generation module meet the third condition, determining the speed adjustment amount of the fuel generator module based on the output frequency of the fuel generator module and the speed-output frequency relationship;

[0021] adjusting the speed of the fuel generator module based on the speed adjustment amount of the fuel generator module;

[0022] The third condition is that: the power change of the load is greater than a first threshold, the power generation power of the photovoltaic power generation module is less than a second power threshold, and the second power threshold is less than the first power threshold.

[0023] In an exemplary embodiment of the present disclosure, adjusting the speed of the fuel generator module based on the speed adjustment amount of the fuel generator module includes:

[0024] Determining a first step length based on the speed adjustment amount of the fuel generator module and the first time length, and adjusting the speed of the fuel generator module based on the first step length;

[0025] The first duration is the duration for the power generation of the photovoltaic power generation module to increase from a first power threshold to a second power threshold.

[0026] In an exemplary embodiment of the present disclosure, controlling the fuel generator module to supply power to the load through the energy conversion module based on the working parameters of the fuel generator module includes:

[0027] Based on the load parameters of the load and the working parameters of the fuel generator module, the fuel generator module is controlled to enter a rated power working state and supply power to the load.

[0028] In an exemplary embodiment of the present disclosure, the load parameter includes a total rated power of the load; and the control method further includes:

[0029] In response to the fuel generator module supplying power to the load, when it is monitored that the total rated power of the load meets a fourth condition, switching to the energy storage module to supply power to the load;

[0030] The fourth condition is that the total rated power of the load is less than or equal to the rated output power of the energy storage module.

[0031] In an exemplary embodiment of the present disclosure, the control module is further configured to:

[0032] The rated output power of the energy storage module is calculated based on the rated voltage and rated current of the energy storage module.

[0033] In a second aspect, an embodiment of the present disclosure provides a fuel-photovoltaic hybrid power supply system, including: a photovoltaic power generation module, an energy storage module, a fuel-electricity generator module, an energy conversion module, and a control module;

[0034] The control module is respectively connected to the photovoltaic power generation module, the energy storage module, the fuel generator module and the energy conversion module; the photovoltaic power generation module, the fuel generator module and the energy conversion module are all electrically connected to the energy storage module; the energy conversion module is electrically connected to the load;

[0035] Wherein, the control module is used to implement the above control method.

[0036] The beneficial effects of a fuel-photovoltaic hybrid power supply system and control method provided by the embodiments of the present disclosure are:

[0037] When the power of the load continues to grow in a short period of time, in order to ensure the stable operation of the load, the fuel-photovoltaic hybrid power supply system provided by the embodiment of the present disclosure can intelligently adjust the power supply mode according to the load demand and light conditions, and can achieve smooth energy switching by real-time monitoring of the working parameters of each module, avoiding voltage and frequency shocks and protecting the load equipment. At the same time, the system can also start the fuel generator in advance when photovoltaic power generation is insufficient to ensure the continuity of power supply, and switch back to photovoltaic power generation when conditions permit to save energy. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] In order to more clearly illustrate the technical solutions in the embodiments of the present disclosure, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present disclosure. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0039] Figure 1 is a structural schematic diagram of a fuel-photovoltaic hybrid power supply system provided by an embodiment of the present disclosure;

[0040] Figure 2 It is a flow chart of a control method for a fuel-photovoltaic hybrid power supply system provided in an embodiment of the present disclosure. DETAILED DESCRIPTION

[0041] In order to enable people in the technical field to better understand the present solution, the technical solution in the embodiment of the present solution will be clearly described below in conjunction with the drawings in the embodiment of the present solution. Obviously, the described embodiment is an embodiment of a part of the present solution, not all of the embodiments. Based on the embodiments in the present solution, all other embodiments obtained by ordinary technicians in the field without creative work should fall within the scope of protection of the present solution.

[0042] The term "including" and any other variations in the specification and claims of this solution and the above drawings mean "including but not limited to", and is intended to cover non-exclusive inclusions and is not limited to the examples listed in the text. In addition, the terms "first" and "second" are used to distinguish different objects, not to describe a specific order.

[0043] The implementation of the present disclosure is described in detail below with reference to specific drawings.

[0044] Figure 1 A schematic diagram of the structure of a fuel-photovoltaic hybrid power supply system provided for an embodiment of the present disclosure. The photovoltaic fuel power generation system is used to supply power to a load. The load can be an electrical device in the power grid, or a single electrical device that exists independently of the power grid, or an energy storage battery. The power demand of these devices is fluctuating and non-constant. For example, the load of the civil power grid has obvious seasonal and periodic characteristics. The power consumption in summer and daytime is significantly greater than that in winter and nighttime, showing an obvious peak and trough effect. Similarly, a single electrical device may exist in various states such as startup, stable operation, and standby, and the power load in different states will also be different. Therefore, the above-mentioned load is a fluctuating load, and the power supply system needs to meet this fluctuation while saving costs as much as possible.

[0045] For this purpose, refer to Figure 1 The present invention discloses a fuel-photovoltaic hybrid power supply system, which includes a photovoltaic power generation module and a fuel generator module. The photovoltaic power generation module is used to generate electricity using the photovoltaic effect of solar energy. Photovoltaic power generation uses a solar panel composed of multiple solar cells containing photovoltaic materials. Multiple photovoltaic modules are connected in series and parallel, together with a supporting structure, to form a photovoltaic array. The photovoltaic power generation module can be composed of one or more of the following: silicon-based solar cells, including monocrystalline silicon and polycrystalline silicon; heterojunction cells; perovskite cells. The fuel generator module can be a traditional internal combustion engine for power generation, and the internal combustion engine can be a gasoline engine, a diesel engine, a hydrogen engine, or a biogas energy engine. The generator can be directly mechanically coupled to the internal combustion engine, or it can be mechanically coupled to the steam turbine, and the steam turbine uses the heat energy generated by the internal combustion engine to do work.

[0046] The photovoltaic power generation module and the fuel generator module are coupled to the energy conversion module, for example, electrically connected. The energy conversion module includes an inverter, a transformer, a rectifier and a current monitoring system, which is used to couple the power generated by the photovoltaic power generation module and / or the fuel generator module to the load.

[0047] Preferably, the fuel-photovoltaic hybrid power supply system also includes an energy storage module. The energy storage module is used to store excess power generated by the photovoltaic power generation module and / or the fuel generator module, and to supply power to the load when the power demand of the load exceeds the maximum power generation power of the photovoltaic power generation module and / or the fuel generator module, thereby realizing the function of peak shaving and valley filling. According to one aspect of the present disclosure, the photovoltaic power generation module, the fuel generator module, the energy conversion module and the energy storage module of the fuel-photovoltaic hybrid power supply system are all in communication connection with the control module;

[0048] The control module is respectively connected to the photovoltaic power generation module, the energy storage module, the fuel generator module and the energy conversion module in communication; the photovoltaic power generation module, the fuel generator module and the energy conversion module are all electrically connected to the energy storage module; and the energy conversion module is also electrically connected to the load.

[0049] Corresponding to a fuel-photovoltaic hybrid power supply system in the above embodiment, Figure 2 is a flow chart of a control method for a fuel-photovoltaic hybrid power supply system provided by an embodiment of the present disclosure, with reference to Figure 2 , the control method comprises:

[0050] S101: when it is monitored that the load parameter of the load and the power generation parameter of the photovoltaic power generation module meet a first condition, determining the working parameter of the fuel generator module based on the power generation parameter of the photovoltaic power generation module;

[0051] S102: Based on the working parameters of the fuel generator module, the fuel generator module is controlled to supply power to the load through the energy conversion module; wherein the load parameters of the load include the power change of the load, and the power generation parameters of the photovoltaic power generation module include the power generation power of the photovoltaic power generation module; the first condition is: the power change of the load is greater than the first threshold value, and the power generation power of the photovoltaic power generation module is less than the first power threshold value.

[0052] In this embodiment, the load parameters of the load may also be, for example, power parameters, voltage parameters, current parameters, load type, working time characteristics of the load, etc. The total power of the load can be calculated based on the voltage and current of the load, and the time when the total power of the load will increase can be obtained based on the working time characteristics of the load. For example, the load is equipment in a factory. When workers go to work, some equipment starts to run, and the total power of the load increases. The output power of the fuel generator can be obtained based on the total power of the load, and the fuel supply and intake volume can be obtained based on the output power of the fuel generator and the energy conversion efficiency of the fuel generator. In addition, the output frequency of the load can also be obtained based on the load type. Because the output frequency of the fuel generator matches the output frequency of the load, the output frequency of the fuel generator can be determined based on the load type, and then the generator speed can be determined (the generator speed is consistent with the output frequency).

[0053] The power generation parameters of the photovoltaic power generation module can also be, for example, power parameters, light parameters, etc. The output power (power parameters) of the photovoltaic power generation module can be calculated based on the light intensity (light parameters) and the photoelectric conversion efficiency. The start-up time of the fuel generator and the output power of the fuel generator can be predicted based on the output power of the photovoltaic power generation module and the total power of the load. The fuel supply and air intake can be obtained based on the output power of the fuel generator and the energy conversion efficiency of the fuel generator. Similarly, the output frequency of the fuel generator needs to match the output frequency of the photovoltaic power generation module. Therefore, the output frequency of the fuel generator can be obtained based on the output frequency of the photovoltaic power generation module, and then the generator speed can be determined.

[0054] The working parameters of the fuel generator module may also be, for example, power parameters, frequency parameters, fuel parameters, etc. The fuel parameters may be fuel supply, air intake, engine speed, etc. According to the above-mentioned load parameters and the power generation parameters of the photovoltaic power generation module, it can be concluded that the power parameters of the fuel generator module are related to the load parameters of the load and the power generation parameters of the photovoltaic power generation module. According to the load parameters of the load and the power generation parameters of the photovoltaic power generation module, the output power, output frequency, fuel supply, air intake, engine speed and other parameters of the fuel generator can be calculated.

[0055] The operating parameters of the energy storage module may be, for example, capacity parameters, voltage parameters, and charge and discharge parameters.

[0056] Preferably, the energy storage module can be a battery, and the energy conversion module can be an inverter. The control module can monitor each module, record the light intensity, output power, output frequency of the photovoltaic power generation module, record the power information of the energy storage module, record the fuel consumption and output power of the fuel generator, etc.

[0057] Under normal circumstances, the photovoltaic power generation module initially supplies power to the load. When the load power is small and does not change for a long time, the photovoltaic power generation module can be powered independently, or the photovoltaic power generation module and the energy storage module can be used together to power the load. When it is detected that the photovoltaic power generation module is not able to supply power independently, the energy storage module is started to supply power. When it is detected that the energy storage module is not able to supply power, the fuel generator is started to supply power to the load, and the energy storage module and the photovoltaic power generation module are disconnected from the load and stop supplying power to the load.

[0058] When the power of the load continues to grow in a short period of time, and the output power of the photovoltaic power generation module is about to fail to meet the output power requirement of the load due to the influence of sunlight, the fuel generator module can be directly started when the photovoltaic power generation module is at the critical power value to ensure the stable operation of the load. The method provided in this embodiment does not require the energy storage module to participate in supplying power to the load, because when the power of the load continues to grow in a short period of time, it is difficult for the energy storage module to provide a stable voltage. Therefore, when the output power of the photovoltaic power generation module cannot meet the power output of the load, it can be directly switched to the fuel generator module to supply power to the load. Specifically:

[0059] The control module monitors the working status of the photovoltaic power generation module in real time. When it is detected that the photovoltaic power generation module is at the first power threshold, the output parameters of the photovoltaic power generation module are obtained, and the fuel generator module is pre-started at the same time; when it is detected that the photovoltaic power generation module is at the second power threshold, the output parameters of the fuel generator module are obtained, and the fuel generator module is controlled to adjust the working parameters of the fuel generator module according to the power generation parameters of the photovoltaic power generation module. When the output parameters of the fuel generator module and the photovoltaic power generation module are consistent, the system can switch the photovoltaic power generation module to the fuel generator module, which can ensure a smooth transition of voltage and frequency and avoid voltage and frequency shocks to the load.

[0060] In order to save energy to the maximum extent, the control method provided in this embodiment also includes:

[0061] When the power generation parameters of the photovoltaic power generation module and the operating parameters of the fuel generator module meet the following conditions:

[0062] The output power of the photovoltaic power generation module is greater than or equal to the output power of the load, and the output power of the fuel generator module is the same as the output power of the photovoltaic power generation module;

[0063] The power generation parameters of the photovoltaic power generation module are determined based on the working parameters of the fuel generator module, and the photovoltaic power generation module is controlled based on the power generation parameters to supply power to the load through the energy conversion module.

[0064] For example, when the load power continues to grow in a short period of time, the control module monitors the working status of the fuel generator module in real time, and predicts the switching time of the photovoltaic power generation module according to environmental characteristics; the control module obtains the output parameters of the fuel generator module, and pre-starts the photovoltaic power generation module to obtain the output parameters of the photovoltaic power generation module. When it is detected that the output power of the fuel generator module is consistent with that of the photovoltaic power generation module, and the output power of the photovoltaic power generation module meets the load demand, the system can switch the fuel generator module to the photovoltaic power generation module, which can ensure a smooth transition of voltage and frequency and avoid voltage and frequency shocks to the load.

[0065] In this embodiment, the system includes three power supply modules. When the photovoltaic power generation module or the fuel engine power generation module is insufficiently powered, the output parameters of the other power supply module can be adjusted according to the output parameters of one of the power supply modules to ensure that the output parameters of the two modules are consistent, so as to avoid voltage and frequency shocks to the load when the energy is switched. After the energy is switched, if it is monitored that the power of the energy storage module has not reached the maximum capacity, the photovoltaic power generation module or the fuel engine power generation module can be controlled to charge the energy storage module.

[0066] It can be concluded from the above that when the power of the load continues to grow in a short period of time, in order to ensure the stable operation of the load, the fuel-photovoltaic hybrid power supply system provided by the embodiment of the present disclosure can intelligently adjust the power supply mode according to the load demand and light conditions, and can achieve smooth energy switching by real-time monitoring of the working parameters of each module, avoiding voltage and frequency shocks and protecting the load equipment. At the same time, the system can also start the fuel generator in advance when photovoltaic power generation is insufficient to ensure the continuity of power supply, and switch back to photovoltaic power generation when conditions permit to save energy.

[0067] In one embodiment of the present disclosure, the control method further includes:

[0068] When it is monitored that the load parameters of the load and the power generation parameters of the photovoltaic power generation module meet the second condition, determining the working parameters of the energy storage module, and controlling the energy storage module to supply power to the load through the energy conversion module based on the working parameters of the energy storage module;

[0069] The second condition is that the power change of the load is less than or equal to the first threshold, and the power generation power of the photovoltaic power generation module is less than the first power threshold.

[0070] In this embodiment, the load parameter of the load includes the power variation of the load, and the power variation of the load indicates the change of the power of the load within a certain period of time. For example, the stadium needs to hold an important event, and within the second time period (for example, 1 hour), the output power of all the equipment in use in the stadium increases from 15kW to 200kW.

[0071] The power generation parameters of photovoltaic power generation modules include the power generation of photovoltaic power generation modules. The power generation of photovoltaic power generation modules refers to the total amount of solar energy converted into electrical energy by photovoltaic power generation modules within a certain period of time. It is a key indicator to measure the performance and actual power generation capacity of photovoltaic power generation modules. The factors affecting the power generation of photovoltaic power generation modules include light intensity, type and efficiency of photovoltaic cells, area and installation angle and orientation of photovoltaic modules, ambient temperature, etc. When photovoltaic power generation modules are installed in a designated area, the main factor affecting the power generation of photovoltaic power generation modules comes from light intensity. The stronger the light intensity, the more obvious the photovoltaic effect in the photovoltaic cell, and the more electrical energy is generated. On cloudy days or in the early morning and evening of a day, the light intensity will be relatively low, and the power generation will be reduced accordingly.

[0072] In this embodiment, the power change of the load and the power generation parameters of the photovoltaic power generation module affect the energy switching of the system. The first condition is: the power change of the load is greater than the first threshold, and the power generation power of the photovoltaic power generation module is less than the first power threshold. Among them, the first threshold is determined according to the battery type and output power of the energy storage module. The first power threshold is the critical power generation power of the photovoltaic power generation module. If the power generation power is less than the critical power generation power, it indicates that the photovoltaic power generation module will soon be difficult to support the output power demand of the load, and other power supply modules are required to assist in power supply, or completely powered by other power supply modules. However, when the power change of the load is large, the energy storage module cannot maintain a stable supply of load power. Therefore, this embodiment proposes that the fuel generator module can be directly started according to the working parameters of the photovoltaic power generation module to power the load, so as to improve the stability of power supply when the load increases. When the power change of the load is less than or equal to the first threshold, it indicates that the energy storage module can meet the output power demand of the load. Therefore, when the photovoltaic power generation module is insufficient, the system can switch to the energy storage module, and the energy storage module supplies power to the load.

[0073] It can be concluded from the above that this embodiment intelligently switches the energy supply module by comprehensively considering the power change of the load and the power generation power of the photovoltaic power generation module, thereby ensuring the stability and efficiency of power supply.

[0074] In one embodiment of the present disclosure, the power generation parameters of the photovoltaic power generation module also include the light intensity and output power of the photovoltaic power generation module, and the working parameters of the fuel generator module also include the pre-start time of the fuel generator module;

[0075] The working parameters of the fuel generator module are determined based on the power generation parameters of the photovoltaic power generation module, including:

[0076] The pre-start time of the fuel generator module is determined based on the light intensity, output power and environmental characteristics of the photovoltaic power generation module.

[0077] In this embodiment, first, it is necessary to monitor the light intensity and output power of the photovoltaic power generation module in real time. The light intensity can be obtained by light sensors, which are usually installed near the photovoltaic power generation module and can accurately measure the intensity of solar radiation received per unit area. The output power is monitored by installing a power sensor on the output circuit of the photovoltaic power generation module to directly measure the electric power generated. The environmental characteristics of the photovoltaic power generation module include but are not limited to weather conditions, seasonal characteristics, sunrise and sunset times, temperature, geographical location and other information. This information can be obtained through weather station data, geographic information system data or additionally installed environmental sensors.

[0078] When it is determined that the power generation capacity of the photovoltaic power generation module is about to be insufficient to meet the load demand based on the monitored light intensity, output power and environmental characteristics, the pre-start time of the fuel generator module needs to be determined. For example, the current time is moment a, and according to the sunset time and light intensity data, the power generation capacity of the photovoltaic power generation module can still meet the load demand 30 minutes later, and the power generation capacity of the photovoltaic power generation module is insufficient to meet the load demand 45 minutes later. Therefore, the pre-start time of the fuel generator module can be moment b 30 minutes later.

[0079] From the above, it can be concluded that since it takes some time for the fuel generator module to reach the rated power after starting, if it is started when it is monitored that the power generation capacity of the photovoltaic power generation module is insufficient to meet the load demand, it is difficult to ensure stable power supply to the load. Therefore, this embodiment proposes to monitor photovoltaic parameters and environmental characteristics in real time, and accurately predict the start-up time of the backup power supply module, which is conducive to maintaining stable power supply to the load and avoiding power outages of the load.

[0080] In one embodiment of the present disclosure, the power generation parameters of the photovoltaic power generation module include the output frequency of the photovoltaic power generation module; the operating parameters of the fuel generator module include the output frequency of the fuel generator module;

[0081] The working parameters of the fuel generator module are determined based on the power generation parameters of the photovoltaic power generation module, including:

[0082] The phase of the output voltage of the fuel generator module is determined based on the output voltage of the photovoltaic power generation module. In this embodiment, the output voltage phase of the photovoltaic power generation module needs to be consistent with the output voltage phase of the fuel generator module. If the phases are inconsistent, an instantaneous voltage difference will be generated during switching, resulting in an impact current. The output voltage of the photovoltaic power generation module can be collected using a voltage sensor, and the output voltage phase can be obtained from the output voltage of the photovoltaic power generation module using a three-phase circuit. Because the output voltage phase of the photovoltaic power generation module needs to be consistent with the output voltage phase of the fuel generator module, after determining the output voltage phase of the photovoltaic power generation module, the output voltage phase of the fuel generator module is also determined.

[0083] From the above, it can be concluded that the output voltage phase of the photovoltaic power generation module is consistent with the output voltage phase of the fuel generator module, which can ensure that damage to the load is avoided during the energy switching power supply process.

[0084] In one embodiment of the present disclosure, the control method further includes:

[0085] When it is monitored that the load parameter of the load and the power generation parameter of the photovoltaic power generation module meet the third condition, the speed adjustment amount of the fuel generator module is determined based on the output frequency of the fuel generator module and the speed-output frequency relationship;

[0086] adjusting the speed of the fuel generator module based on the speed adjustment amount of the fuel generator module;

[0087] The third condition is that: the power change of the load is greater than the first threshold, the power generation power of the photovoltaic power generation module is less than the second power threshold, and the second power threshold is less than the first power threshold.

[0088] The speed of the fuel generator module is adjusted based on the speed adjustment amount of the fuel generator module, including:

[0089] Determine a first step length based on the speed adjustment amount of the fuel generator module and the first time length, and adjust the speed of the fuel generator module based on the first step length;

[0090] The first duration is the duration for the power generation of the photovoltaic power generation module to increase from a first power threshold to a second power threshold.

[0091] In this embodiment, the first power threshold and the second power threshold are power thresholds determined by the control module in the system according to the output power requirement of the load, the power change of the load, and the light intensity. The first power threshold can be determined based on a first formula, where the first formula is:

[0092]

[0093] in, represents the first power threshold, Represents the safety factor, which is a positive number greater than 1. The electric power required by the load under normal operation. Indicates the change value of load power in the first time period. It indicates the predicted value of the effective light time that the photovoltaic power generation module can receive. Indicates the light intensity, Represents the total area of ​​photovoltaic power generation modules receiving light, Indicates the photoelectric conversion efficiency of photovoltaic power generation modules.

[0094] The second power threshold may be determined based on a second formula, which is:

[0095]

[0096] in, is the critical coefficient, which is determined according to the historical power generation power of the photovoltaic power generation module.

[0097] In this embodiment, when it is monitored that the power change of the load is greater than the first threshold value and the power generation power of the photovoltaic power generation module is less than the second power threshold value, it indicates that the system can switch the power supply module from the photovoltaic power generation module to the fuel engine power generation module. At this time, the phase of the output voltage of the fuel generator module needs to be matched with the phase of the output voltage of the photovoltaic power generation module to ensure a smooth transition of the power supply module. When the fuel generator module is pre-started, the output frequency of the fuel generator module is generally 48Hz, while the output frequency of the load is generally 50Hz. There is a specific relationship between the output frequency of the fuel generator module and the engine speed. Therefore, the output frequency of the generator can be adjusted to 50Hz by adjusting the speed according to the speed-output frequency relationship.

[0098] Exemplarily, the speed of the fuel generator module is adjusted as follows: determining a first step length based on the speed adjustment amount of the fuel generator module and the first time length, and adjusting the speed of the fuel generator module based on the first step length;

[0099] The first duration is the duration of the power generation of the photovoltaic power generation module from the first power threshold to the second power threshold, and the first duration can be calculated by the control module according to the time data of the power generation of the photovoltaic power generation module monitored. For example, the system records the photovoltaic power generation once a minute. When the power generation drops from higher than the first power threshold to lower than the second power threshold for the first time at a certain moment, the accumulated recorded duration is the first duration.

[0100] For a fuel generator, a specific speed corresponds to a specific frequency, for example, a two-pole synchronous generator, a 50Hz frequency corresponds to 3000 rpm. The speed adjustment is obtained by calculating the difference between the current speed of the generator and the specific speed. The first step length can be determined based on the adjustment amount and the first duration: the first step length L = (specific speed - current speed) / first duration. For example, when the first duration is relatively large, the first step length is relatively small, that is, the speed adjustment amount is small each time; when the first duration is relatively small, the first step length is relatively large, that is, the speed adjustment amount is large each time.

[0101] It can be concluded from the above that this embodiment achieves a rapid response to load power changes by finely controlling the speed of the fuel generator module. When the load power changes greatly and the photovoltaic power generation is insufficient, the system can accurately determine and adjust the speed of the fuel generator to ensure stable power supply. At the same time, the adjustment step length is determined by the duration of the photovoltaic power change, making the adjustment process smoother, reducing system fluctuations, and improving overall energy efficiency and operational reliability.

[0102] In one embodiment of the present disclosure, the parameters of the load include the total rated power of the load; the control module is further configured to:

[0103] In response to the fuel generator module supplying power to the load, when it is monitored that the total rated power of the load meets a fourth condition, switching to the energy storage module to supply power to the load;

[0104] The fourth condition is that the total rated power of the load is less than or equal to the rated output power of the energy storage module.

[0105] In this embodiment, the control module can monitor the total rated power of the load in real time. When the total rated power of the load is less than or equal to the rated output power of the energy storage module, it indicates that there are not too many high-power devices in the load, and the energy storage module has the ability to independently undertake the task of powering the load. In order to save energy, the control module can perform a switching operation to switch the power supply line from the fuel generator module to the energy storage module, thereby realizing stable power supply from the energy storage module to the load.

[0106] For example, in power supply facilities in remote areas, photovoltaic power generation is mainly relied on during the day. In the evening, due to insufficient sunlight, the photovoltaic power generation module stops working and the fuel generator starts to supply power to the load. As the nighttime electricity consumption trough approaches, most high-energy-consuming equipment is shut down, and the total rated power of the load drops significantly. When it drops to less than or equal to the rated output power of the energy storage module, it can be switched to the energy storage module for power supply, reducing fuel consumption, noise and exhaust emissions.

[0107] In one embodiment of the present disclosure, the control method is also used for:

[0108] The rated output power of the energy storage module is calculated based on the rated voltage and rated current of the energy storage module.

[0109] In this embodiment, the rated voltage and rated current of the energy storage module can be collected by high-precision voltage sensors and current sensors respectively. The voltage sensor can be a type that can accurately sense voltage based on the voltage division principle, Hall effect, etc., closely fits the output end of the energy storage module, and monitors and collects its rated voltage value in real time. The current sensor uses the electromagnetic induction principle or Hall current sensing technology to be connected in series to the output line of the energy storage module to accurately obtain the rated current data.

[0110] The control module can use the internal microprocessor (such as common single-chip microcomputer, ARM processor, etc.) to build a calculation program to calculate the rated power of the energy storage module according to the power calculation formula P=UI (where P is the rated power, U is the rated voltage, and I is the rated current).

[0111] The above embodiments are only used to illustrate the technical solutions of the present disclosure, rather than to limit them. Although the present disclosure has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present disclosure.

Claims

1. A control method for a fuel-photovoltaic hybrid power supply system, characterized in that: Applied to the fuel-photovoltaic hybrid power supply system, The fuel-photovoltaic hybrid power supply system includes a photovoltaic power generation module, an energy storage module, a fuel generator module, an energy conversion module and a control module; The control method comprises: when it is monitored that the load parameter of the load and the power generation parameter of the photovoltaic power generation module meet a first condition, determining the working parameter of the fuel generator module based on the power generation parameter of the photovoltaic power generation module; Based on the working parameters of the fuel generator module, the fuel generator module is controlled to supply power to the load through the energy conversion module; The load parameter of the load includes a power variation of the load, and the power generation parameter of the photovoltaic power generation module includes a power generation power of the photovoltaic power generation module; the first condition is: the power variation of the load is greater than a first threshold, and the power generation power of the photovoltaic power generation module is less than a first power threshold; The first power threshold is determined based on a first formula, where the first formula is: in, represents the first power threshold, Represents the safety factor, which is a positive number greater than 1. The electric power required by the load under normal operation. Indicates the change value of load power in the first time period. It indicates the predicted value of the effective light time received by the photovoltaic power generation module. Indicates the light intensity, Represents the total area of ​​photovoltaic power generation modules receiving light, Indicates the photoelectric conversion efficiency of photovoltaic power generation modules; The control method further comprises: when it is monitored that the load parameter of the load and the power generation parameter of the photovoltaic power generation module meet a third condition, determining the speed adjustment amount of the fuel generator module based on the output frequency of the fuel generator module and the speed-output frequency relationship; The third condition is: the power change of the load is greater than the first threshold, the power generation power of the photovoltaic power generation module is less than the second power threshold, and the second power threshold is less than the first power threshold; The second power threshold is determined based on a second formula, which is: in, is the critical coefficient, which is determined according to the historical power generation power of the photovoltaic power generation module.

2. A control method for a fuel-photovoltaic hybrid power supply system according to claim 1, characterized in that: Also includes: When it is monitored that the load parameters of the load and the power generation parameters of the photovoltaic power generation module meet the second condition, determining the working parameters of the energy storage module, and controlling the energy storage module to supply power to the load through the energy conversion module based on the working parameters of the energy storage module; The second condition is that: the power change of the load is less than or equal to a first threshold, and the power generation power of the photovoltaic power generation module is less than the first power threshold.

3. The control method of a fuel-photovoltaic hybrid power supply system according to claim 1, characterized in that: The power generation parameters of the photovoltaic power generation module also include the light intensity and output power of the photovoltaic power generation module, and the working parameters of the fuel generator module also include the pre-start time of the fuel generator module; The step of determining the operating parameters of the fuel generator module based on the power generation parameters of the photovoltaic power generation module includes: The pre-start time of the fuel generator module is determined based on the light intensity and output power of the photovoltaic power generation module and the environmental characteristics of the photovoltaic power generation module.

4. The control method of a fuel-photovoltaic hybrid power supply system according to claim 1, characterized in that: The step of determining the operating parameters of the fuel generator module based on the power generation parameters of the photovoltaic power generation module includes: The phase of the output voltage of the fuel generator module is determined based on the output voltage of the photovoltaic power generation module.

5. The control method of a fuel-photovoltaic hybrid power supply system according to claim 1, characterized in that: Also includes: The speed of the fuel generator module is adjusted based on the speed adjustment amount of the fuel generator module.

6. A control method for a fuel-photovoltaic hybrid power supply system as claimed in claim 5, characterized in that: The adjusting the speed of the fuel generator module based on the speed adjustment amount of the fuel generator module includes: Determining a first step length based on the speed adjustment amount of the fuel generator module and the first time length, and adjusting the speed of the fuel generator module based on the first step length; The first duration is the duration for the power generation of the photovoltaic power generation module to increase from a first power threshold to a second power threshold.

7. The control method of a fuel-photovoltaic hybrid power supply system according to claim 1, characterized in that: The controlling the fuel generator module to supply power to the load through the energy conversion module based on the working parameters of the fuel generator module comprises: Based on the load parameters of the load and the working parameters of the fuel generator module, the fuel generator module is controlled to enter a rated power working state and supply power to the load.

8. The control method of a fuel-photovoltaic hybrid power supply system according to claim 1, characterized in that: The load parameters of the load include the total rated power of the load; The control method further comprises: In response to the fuel generator module supplying power to the load, when it is monitored that the total rated power of the load meets a fourth condition, switching to the energy storage module to supply power to the load; The fourth condition is that the total rated power of the load is less than or equal to the rated output power of the energy storage module.

9. A control method for a fuel-photovoltaic hybrid power supply system as claimed in claim 8, characterized in that: Also includes: The rated output power of the energy storage module is calculated based on the rated voltage and rated current of the energy storage module.

10. A fuel-photovoltaic hybrid power supply system, characterized in that: Including photovoltaic power generation module, energy storage module, fuel generator module, energy conversion module and control module; The control module is respectively connected to the photovoltaic power generation module, the energy storage module, the fuel generator module and the energy conversion module; the photovoltaic power generation module, the fuel generator module and the energy conversion module are all electrically connected to the energy storage module; the energy conversion module is electrically connected to the load; Wherein, the control module is used to implement the control method as described in any one of claims 1-9.

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