Wind-solar hybrid energy storage system

Abstract

A wind-solar hybrid energy storage system is composed of a wind power generation system, a photovoltaic power generation system, a power grid system, an electrochemical energy storage system, a heat energy storage system, a load system, a PCS system and a mode switching system, and the wind power generation system, the photovoltaic power generation system and the power grid system are connected in parallel to an alternating current bus through circuits. The electrochemical energy storage system and the thermal energy storage system are also connected in parallel to the alternating current bus through the DC-AC system, and the load system is connected in the alternating current bus through the transformer; and the PCS system and the mode switching system are connected with the whole wind-solar hybrid storage system through logic signals and programming functions to realize process control and mode switching.

Description

Technical Field

[0001] The present invention relates to the technical field of wind power generation, photovoltaic power generation and hybrid energy storage, and in particular to a wind-solar hybrid energy storage system. Background Art

[0002] With the development of the new energy industry, the demand for electricity in society is increasing, and the requirements of power users for power quality and power supply stability are gradually increasing. The role of microgrids is becoming increasingly important. The peak of household electricity load is mostly concentrated in the daytime, and the power consumption is less at night, resulting in an increase in the peak-to-valley difference. However, power stations work all day, which easily leads to waste of power resources at night. Wind power generation and photovoltaic power generation are affected by factors such as weather and terrain, resulting in unstable voltage and power. This problem is becoming more and more prominent, especially in the context of large-scale development of large generators and nuclear power generators in my country. In recent years, energy storage technology has been continuously developed and improved. Common methods include pumped storage, heat storage and cold storage, chemical battery storage and flywheel storage. Among them, chemical battery energy storage, as an emerging technology, has been applied in MW-level industrial energy storage power stations at home and abroad. It is mainly built by power companies to solve the power allocation and operation problems of the power grid, but ignores the demand for household or other small power storage. Due to the limitations of capacity configuration and response speed of a single energy storage system, it is difficult to meet the needs of modern power systems. The hybrid energy storage system combines their respective advantages and can well make up for the defects of single energy storage. Therefore, it is particularly important to propose a wind-solar hybrid storage model and construction method to improve the power quality and continuous power supply capability of wind and solar power generation. Summary of the invention

[0003] In order to solve the problems in the prior art, the present invention provides a wind-solar hybrid energy storage system. The wind-solar hybrid energy storage system can effectively smooth the power fluctuations of wind and solar power generation, reduce voltage fluctuations, frequency deviations and harmonic distortions, and thus significantly improve the quality of electric energy. In addition, the system can also enhance the continuity of wind and solar power generation, transform wind energy and solar energy from intermittent energy sources into continuous energy sources, and improve the stability and economy of wind and solar power generation access to the grid. By reducing the wind and solar power abandonment rates, the system further improves the utilization rate of wind and solar energy, and gives full play to the advantages of the wind-solar hybrid storage system in improving the utilization efficiency of renewable energy and the reliability of power supply.

[0004] The present invention is achieved through the following technical solutions:

[0005] A wind-solar hybrid energy storage system is composed of a wind power generation system, a photovoltaic power generation system, a power grid system, an electrochemical energy storage system, a thermal energy storage system, a load system, a PCS system and a mode switching system. The wind power generation system, the photovoltaic power generation system and the power grid system are connected in parallel on an AC bus through circuits, the electrochemical energy storage system and the thermal energy storage system are also connected in parallel to the AC bus through a DC-AC system, and the load system is connected to the AC bus through a transformer; the PCS system and the mode switching system realize process control and mode switching of the entire wind-solar hybrid storage system connection through logic signals and programming functions.

[0006] Furthermore, the wind power generation system includes a wind turbine generator set and a photovoltaic generator set, an AC-DC-AC control system, and an MPPT control system; the system uses RT-LAB and Simulink to build a simulation of a real wind and solar power generation system;

[0007] The wind-solar generator set is a power generation system composed of a direct-drive permanent magnet synchronous generator and a solar photovoltaic panel, which is used to provide energy for the load system and the energy storage system;

[0008] The AC-DC-AC control system is a controllable rectifier inverter control device, the purpose of which is to control the electric energy generated by the wind turbine to reach an ideal voltage and meet the voltage level required for grid connection;

[0009] The MPPT control system is a maximum power point tracking control algorithm, the purpose of which is to ensure that the photovoltaic power generation system can always operate at the maximum power point as the solar irradiance changes, thereby improving the efficiency of photovoltaic power generation;

[0010] The photovoltaic power generation unit converts solar energy into electrical energy. The electrical energy generated by the photovoltaic power generation system is used to supply power to electrical loads and is stored in an energy storage system.

[0011] Furthermore, the electrochemical energy storage system includes a battery system, a PQ control system, a VF control system, a DC-AC control system, and a battery PCS system;

[0012] The battery system includes a lithium iron phosphate battery and a lead-acid battery, which is used to store the surplus power of the wind and solar power generation system, or to supply power to the load as a supplementary energy source when the wind and solar power generation system cannot meet the load;

[0013] The PQ control system is used to control the charging and discharging power and voltage of the energy storage system when the entire system is connected to the grid. The voltage is maintained at about 400V, the charging and discharging power is stabilized at 30kW, and the voltage meets the grid voltage.

[0014] The VF control system is used to control the charging and discharging voltage and frequency of the energy storage system when the entire system is off-grid, keep the charging and discharging voltage stable at 230V and reduce the voltage and frequency fluctuation to keep it at ±5%;

[0015] The DC-AC control system is used for inverter control. Since the battery outputs direct current, it needs to be inverted into alternating current when connected to the grid. In this process, inverter control is required to ensure that the voltage after inversion is maintained at 400V and the frequency is maintained at 50Hz, which meets the requirements of grid connection;

[0016] The battery PCS system is used to control the charging and discharging of the energy storage system. By combining the battery SOC, cycle number, load demand, and active power of the power generation system, it comprehensively determines the charging and discharging timing of the energy storage system to ensure that the battery SOC is between 20% and 80%, the cycle number reaches the standard of 5,000 times, and the supply and demand balance of the entire system is maintained.

[0017] Further, a heat storage system includes an electric boiler heater, a water supply tank, a hot water storage tank, and a PCS system;

[0018] The electric boiler heater supplies normal temperature water to the electric boiler heater through the water supply tank, and then the electric boiler heater performs multi-stage circulation heating until the required temperature is reached, and then outputs the hot water to the hot water storage tank;

[0019] The water supply tank and the heat storage tank are a kind of simulation container; the water supply tank can be regarded as an infinite water source, continuously supplying hot water to the heater at a rated flow rate; the heat storage tank is used to receive hot water from the electric boiler and provide hot water to the heat load to meet the demand of the heat load;

[0020] The heat storage PCS system is used to control the operation of the heat storage system. When the wind and solar power generation systems meet the load demand, the heat storage system uses surplus electricity to store heat to supply the heat load demand; when the wind and solar power generation systems do not meet the load demand, the heat storage system stops running to reduce the load demand, allowing the wind and solar power generation systems to supply the main load.

[0021] Further, the load system includes: an electrical load system, a thermal load system, and a load PCS system;

[0022] The electric load system is a simulated electric load device used to simulate a real load device, mainly including a main electric load system and a secondary electric load system, simulating the main electric devices and secondary electric devices in actual situations;

[0023] The heat load system simulates the actual heat load consumption according to the inlet flow state and the actual heat consumption, calculates the outlet flow state and satisfies the law of conservation of mass. For water working fluid, Q=c×m×ΔT is used to calculate the heat loss;

[0024] The load PCS system is used to control the operation of the load. When the active power of the wind and solar power generation system is small and cannot meet all the loads, the PCS system is used to shut down some secondary loads and only retain the power supply of the main loads; when the active power of the wind and solar power generation system reaches a stable power of 1000kW, the secondary loads resume power supply.

[0025] Furthermore, the PCS system includes a full-power converter, a voltage stabilizing circuit, and a control circuit;

[0026] The full-power converter controls the voltage and current of the electricity generated by the wind power generation system and the photovoltaic power generation system through controllable AC-DC-AC and DC-AC circuits to achieve the voltage and current required for grid connection, thereby achieving grid connection;

[0027] The voltage stabilizing circuit passes the electricity generated by the electrochemical energy storage system through the voltage stabilizing circuit to meet the power supply requirements, and then supplies it to the electric load system;

[0028] The control circuit controls the charge and discharge time of the electrochemical energy storage system, the operation time of the heat storage system, the power generation conditions of the wind power generation system and the photovoltaic power generation system, and the operation conditions of the load system.

[0029] Furthermore, the mode switching system dynamically switches the wind-solar hybrid storage system into four different operating conditions, namely, no energy storage operating condition, single electrochemical energy storage operating condition, single thermal energy storage operating condition, and combined heat and power storage operating condition, to explore the system changes under different operating conditions.

[0030] Beneficial Effects

[0031] The wind-solar hybrid energy storage system of the present invention has significant advantages in practical applications. On the power generation side, the model can effectively smooth out power fluctuations caused by changes in wind speed and light intensity, improve the continuous power supply capacity of the wind-solar power generation system, and transform wind energy and solar energy from intermittent energy to continuous energy. On the grid side, the system can reduce voltage fluctuations, voltage deviations, and harmonic distortions when wind and solar power generation are connected to the grid, thereby improving the quality of electric energy, reducing the impact on the grid, and improving the feasibility and economy of wind and solar grid access. On the load side, the model can improve the stability of power supply to the load, reduce power supply fluctuations, improve low voltage ride-through problems, and at the same time reduce the need to purchase electricity from the grid, thereby improving the economy of the overall source-grid-load-storage system;

[0032] The wind-solar hybrid storage simulation system was built using MATLAB / Simulink and RT-LAB semi-physical simulation platforms, demonstrating significant advantages and practical effects in many aspects. The system integrates wind power generation, photovoltaic power generation, electrochemical energy storage and thermal energy storage systems, as well as power grids and various load systems. Through the coordinated operation of the process control system and the optimized operation of the mode switching system under different working conditions, the various parts of the system can work together efficiently. The wind power generation and photovoltaic power generation systems are connected to the grid in parallel, and the energy storage system is connected to the busbar through boost circuits and transformers. This configuration enables the wind-solar hybrid storage system to effectively smooth out power fluctuations caused by changes in wind speed and light intensity, significantly reduce grid voltage fluctuations, frequency deviations and harmonic distortion, and improve power quality. In addition, the energy storage system can store energy when there is excess power and release energy when there is insufficient power, thereby balancing supply and demand and reducing wind and solar power abandonment. This not only improves the utilization rate of wind and solar energy, but also optimizes the economic efficiency of wind and solar power grid access. On the grid side, the system improves the feasibility and economic benefits of wind and solar power grid access by improving power quality and reducing the impact of wind and solar power grid access. On the load side, the wind-solar hybrid storage system enhances the stability of load power supply, reduces power supply fluctuations, and improves low voltage ride-through problems. At the same time, the introduction of the energy storage system also reduces the need to purchase electricity from the power grid, improving the economy of the overall source-grid-load-storage system. Through simulation system verification, the wind-solar hybrid storage system demonstrated superior performance and stable operation capabilities under various operating conditions. It significantly improves the continuous power supply capacity of the wind-solar power generation system, transforming intermittent energy into a more stable energy supply.

[0033] Combined with the actual situation and policy guidance in Ordos, the research and optimization work based on the RT-LAB platform further highlights the practical application effect of the system. Ordos has abundant wind and solar energy resources, but the changes in wind speed and light intensity lead to the instability of renewable energy generation. By analyzing the characteristics of renewable energy generation and load demand in Ordos, the technical requirements for energy storage configuration are determined to ensure that the model adapts to the local actual situation. The RT-LAB platform is used to perform real-time simulation of the source-grid-load-storage integrated control strategy, evaluate the effects of different energy storage configuration schemes, and optimize the energy storage configuration scheme based on the simulation results to maximize cost-effectiveness and reduce the phenomenon of wind and power abandonment. Through these research and optimization work, the application of wind-solar hybrid storage system in Ordos has significantly improved the stability and continuity of renewable energy generation, optimized the power quality, reduced the waste of power resources, and enhanced the efficient use of renewable energy. At the same time, the evaluation of policy incentive mechanisms ensures the economy and sustainable development of energy storage projects. In summary, the wind-solar hybrid energy storage system, combined with the actual situation in the Ordos area, not only improves the stability and economy of wind and solar power generation in the area, but also provides a scientific and reasonable energy storage configuration plan for other similar regions, promoting the development and application of new energy technologies. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 This is the operation logic diagram of the wind-solar hybrid storage system of the present invention

[0035] Figure 2 This is a structural block diagram of the wind-solar hybrid storage system of the present invention;

[0036] Figure 3 It is a structural block diagram of the wind-solar power generation system of the present invention;

[0037] Figure 4 It is a structural block diagram of the electrochemical energy storage system of the present invention;

[0038] Figure 5 It is a structural block diagram of the thermal energy storage system of the present invention;

[0039] Figure 6 It is a structural block diagram of the power grid system of the present invention;

[0040] Figure 7 It is a structural block diagram of the electrical load and thermal load of the present invention;

[0041] Figure 8 It is the block diagram of PCS system structure;

[0042] Fig. 9 It is a monitoring diagram of the wind power generation system;

[0043] Fig.10 It is the monitoring diagram of photovoltaic power generation system;

[0044] Fig.11 It is the monitoring diagram of the electrochemical energy storage system;

[0045] Fig.12 It is the monitoring diagram of the thermal energy storage system;

[0046] Fig.13 This is a comparison chart of active power on the power generation side with and without energy storage;

[0047] Fig.14 This is a comparison chart of active power on the grid side without and with energy storage;

[0048] Fig.15 It is a comparison chart of grid-side harmonic distortion of no energy storage, electric energy storage, thermal energy storage, and electric-thermal combined energy storage;

[0049] Fig.16 It is a comparison chart of grid-side frequency deviations for no energy storage, electric energy storage, thermal energy storage, and electric-thermal combined energy storage; Specific implementation methods

[0051] The model of the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments:

[0052] like Figure 1-16 As shown, the operation logic of the wind-solar hybrid energy storage system designed by the present invention is that first, the wind-solar generator set starts to output electric energy to the outside world through the changes in the external wind speed and solar irradiance, and the control signal of the wind-solar power generation system is also input into the PCS system. In the PCS system, it is determined whether the active power of the wind-solar power generation meets the load demand. If it does not meet the load demand, the PCS system outputs control signals to the battery energy storage system and the power grid system. First, the battery discharges. If it still cannot meet the load demand, the power grid system discharges to meet the load demand. If the wind-solar power generation system meets the load demand, the PCS system outputs control signals to the battery energy storage system and the heat storage system. The battery energy storage system starts to charge and the heat storage system starts to store heat. If there is still a surplus of electricity at this time, power is supplied to the power grid to realize the access of wind-solar power generation to the grid.

[0053] like Figure 2 As shown, a wind-solar hybrid energy storage system of the present invention includes a wind-solar power generation system, a power grid system, an electrochemical energy storage system, a heat storage system, a load system and a PCS system;

[0054] The wind and solar power generation system is as follows Figure 3 As shown, it mainly includes direct-drive permanent magnet synchronous wind turbine generator set and solar photovoltaic generator set. By inputting simulated wind speed, solar irradiance, ambient temperature and other parameters, virtual wind and solar power generation is realized to supply power to electric loads and energy storage systems, and to connect wind and solar power to the grid;

[0055] The electrochemical energy storage system Figure 4 As shown, it mainly includes lithium iron phosphate batteries and lead-acid batteries, which are mainly used to store excess electric energy from wind and solar power generation systems and provide electric energy for load systems;

[0056] The heat storage system is Figure 5 As shown, it mainly includes a heating electric boiler, a heat storage tank, a water supply circulation device and a heat load, which is mainly used to convert the excess electric energy of the wind and solar power generation system into heat energy through the heating electric boiler and store it in the heat storage tank for heating the heat load;

[0057] The power grid system is Figure 6 As shown, it mainly includes simulated power grid and transformer, which are mainly used when the wind and solar power generation system and energy storage system cannot meet the load system requirements. The power grid system acts as an unlimited power source to provide auxiliary power to the load to maintain stable operation of the system. When the wind and solar power generation system can meet the load requirements and has surplus power, it can reversely supply power to the grid to achieve wind and solar access to the grid.

[0058] The load system is as follows Figure 7 As shown, there are three types of loads, namely ordinary electric load, residential load and school load, which are used to consume the electric energy of wind and solar power generation system and simulate the real load system;

[0059] The PCS system is as follows Figure 8 As shown, it includes a wind-solar power generation system inverter control system, an energy storage system charge and discharge control system, and a heat storage system operation control system, which are mainly used to control the wind-solar power generation system to be stably connected to the grid, control the energy storage system to charge the battery when the wind-solar power generation is greater than the load demand, supply power to the load when the wind-solar power generation does not meet the load demand, and control the heat storage system to store the surplus power after the wind-solar power generation meets the load demand;

[0060] The operation of wind and solar power generation system is as follows Fig. 9 and Fig.10 As shown in the figure, the installed capacity of wind turbines and photovoltaic units are both 500kW. The wind turbine power fluctuates greatly at the beginning due to the influence of wind speed fluctuations, and then the active power gradually increases to 500kW as the wind speed increases. The active power of photovoltaic generators also gradually increases to 500kW as the solar irradiance increases. The power generation of wind and solar power generation systems reaches 0.52kWh and 0.54kWh respectively.

[0061] The battery's operating conditions are as follows: Fig.11 As shown, the rated capacity of the battery is 120kWh. When the system starts running, the active power of the wind and solar power generation system is small and does not meet the load demand. The battery stably supplies power to the load. At 2s, the wind and solar power generation system gradually meets the load demand, and the battery performs shallow charging and shallow discharge. After 3.2s, the wind and solar power generation system fully meets the load demand, and the battery performs stable charging. The SOC of the battery drops from the initial state of 60% to 59.972% and then rises to 59.985%, realizing a complete charging and discharging process;

[0062] The operation of the heat storage system is as follows Fig.12 As shown in the figure, the water is continuously heated to the specified temperature (this system is set to 51°C) by the electric heater and then the water is stably supplied to the thermal storage tank. The results show that the SOC of the thermal storage tank increases from 65.5% to 62.514%, and the water storage capacity increases from the initial state of 50m 3 Rise to 50.01m 3 ,The temperature of the heat storage tank rises from the initial state of 40℃ to 40.005℃, and the subsequent heat storage tank will be used to heat the heat load;

[0063] The active power comparison of the power generation side is Fig.13 As shown in the figure, when there is no energy storage system, the wind and solar power generation system is affected by the incoming wind speed and solar irradiance, resulting in unstable power and large fluctuations. When the energy storage system is added, the energy storage system will perform charge and discharge control when the wind and solar power generation fluctuates greatly, smooth out the power fluctuation of wind and solar power generation, improve power generation stability and continuity, and transform wind and solar energy from intermittent energy to continuous energy.

[0064] The active power comparison of the grid side is Fig.14 As shown in the figure, when there is no energy storage system, the active power fluctuation on the grid side reaches nearly 400kW. The reason is that when there is no energy storage, the power of the wind and solar power generation system is unstable and fluctuates greatly, which affects the active power of the grid, resulting in large fluctuations. When the energy storage system is added, the active power on the grid side drops from 400kW to 100kW, which significantly slows down the fluctuation of the grid and reduces the impact on the grid. After adding the energy storage system, the active power of the grid drops by 150kW by supplementing the power supply to the load through the battery. By reducing the power supply of the grid, it can not only reduce the difficulty of power distribution, but also reduce the expenditure on purchasing electricity, and improve the economy of the entire wind and solar hybrid storage system.

[0065] The voltage distortion and frequency deviation on the grid side are as follows: Fig.15 and Fig.16 As shown, by comparing four different working conditions, including no energy storage, electric energy storage, thermal energy storage, and combined heat and power, it is found that combined heat and power has the best effect on improving the power quality on the grid side. Electric energy storage and thermal energy storage have limited improvement on power quality due to their own capacity configuration and response speed. Compared with no energy storage, combined heat and power has a decrease of about 0.2% in voltage distortion and about 1% in frequency deviation. Compared with electric energy storage and thermal energy storage, the voltage distortion has decreased by about 0.12% and the frequency deviation has decreased by 0.15%. It can be seen that the wind-solar hybrid storage model designed in the present invention has good effects in smoothing wind and solar power fluctuations, reducing power distribution difficulties, improving the economic efficiency of wind and solar power generation, and improving the power quality on the power generation side and the grid side.

[0066] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that are not conceived through creative work should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope defined in the claims.

Claims

1. A wind-solar hybrid energy storage system, characterized in that: It consists of a wind power generation system, a photovoltaic power generation system, a power grid system, an electrochemical energy storage system, a thermal energy storage system, a load system, a PCS system and a mode switching system. The wind power generation system, the photovoltaic power generation system and the power grid system are connected in parallel on the AC bus through circuits, the electrochemical energy storage system and the thermal energy storage system are also connected in parallel to the AC bus through a DC-AC system, and the load system is connected to the AC bus through a transformer; the PCS system and the mode switching system connect the entire wind-solar hybrid storage system through logic signals and programming functions to achieve process control and mode switching.

2. The system according to claim 1, characterized in that: The wind power generation system includes wind turbines and photovoltaic generators, AC-DC-AC control systems, and MPPT control systems. The system uses RT-LAB and Simulink to simulate a real wind and solar power generation system. The wind-solar generator set is a power generation system composed of a direct-drive permanent magnet synchronous generator and a solar photovoltaic panel, which is used to provide energy for the load system and the energy storage system; The AC-DC-AC control system is a controllable rectifier inverter control device, the purpose of which is to control the electric energy generated by the wind turbine to reach an ideal voltage and meet the voltage level required for grid connection; The MPPT control system is a maximum power point tracking control algorithm, the purpose of which is to ensure that the photovoltaic power generation system can always operate at the maximum power point as the solar irradiance changes, thereby improving the efficiency of photovoltaic power generation; The photovoltaic power generation unit converts solar energy into electrical energy. The electrical energy generated by the photovoltaic power generation system is used to supply power to electrical loads and is stored in an energy storage system.

3. The system according to claim 1, characterized in that: Electrochemical energy storage system, including battery system, PQ control system, VF control system, DC-AC control system, battery PCS system; The battery system includes a lithium iron phosphate battery and a lead-acid battery, which is used to store the surplus power of the wind and solar power generation system, or to supply power to the load as a supplementary energy source when the wind and solar power generation system cannot meet the load; The PQ control system is used to control the charging and discharging power and voltage of the energy storage system when the entire system is connected to the grid. The voltage is maintained at about 400V, the charging and discharging power is stabilized at 30kW, and the voltage meets the grid voltage. The VF control system is used to control the charging and discharging voltage and frequency of the energy storage system when the entire system is off-grid, keep the charging and discharging voltage stable at 230V and reduce the voltage and frequency fluctuation to keep it at ±5%; The DC-AC control system is used for inverter control. Since the battery outputs direct current, it needs to be inverted into alternating current when connected to the grid. In this process, inverter control is required to ensure that the voltage after inversion is maintained at 400V and the frequency is maintained at 50Hz, which meets the requirements of grid connection; The battery PCS system is used to control the charging and discharging of the energy storage system. By combining the battery SOC, cycle number, load demand, and active power of the power generation system, it comprehensively determines the charging and discharging timing of the energy storage system to ensure that the battery SOC is between 20% and 80%, the cycle number reaches the standard of 5,000 times, and the supply and demand balance of the entire system is maintained.

4. The system according to claim 1, characterized in that: Thermal storage system, including electric boiler heater, water supply tank, hot water storage tank, PCS system; The electric boiler heater supplies normal temperature water to the electric boiler heater through the water supply tank, and then the electric boiler heater performs multi-stage circulation heating until the required temperature is reached, and then outputs the hot water to the hot water storage tank; The water supply tank and the hot water storage tank are a kind of simulation container; The water supply tank can be regarded as an infinite water source, continuously supplying hot water to the heater at a rated flow rate; the heat storage tank is used to receive hot water from the electric boiler and provide hot water to the heat load to meet the demand of the heat load; The heat storage PCS system is used to control the operation of the heat storage system. When the wind and solar power generation systems meet the load demand, the heat storage system uses surplus electricity to store heat to supply the heat load demand; when the wind and solar power generation systems do not meet the load demand, the heat storage system stops running to reduce the load demand, allowing the wind and solar power generation systems to supply the main load.

5. The system according to claim 1, characterized in that: Load system, including: electrical load system, thermal load system, load PCS system; The electric load system is a simulated electric load device used to simulate a real load device, mainly including a main electric load system and a secondary electric load system, simulating the main electric devices and secondary electric devices in actual situations; The heat load system simulates the actual heat load consumption according to the inlet flow state and the actual heat consumption, calculates the outlet flow state and satisfies the law of conservation of mass. For water working fluid, Q=c×m×△T is used to calculate the heat loss; The load PCS system is used to control the operation of the load. When the active power of the wind and solar power generation system is small and cannot meet all the loads, the PCS system is used to shut down some secondary loads and only retain the power supply of the main loads; when the active power of the wind and solar power generation system reaches a stable power of 1000kW, the secondary loads resume power supply.

6. The system according to claim 1, characterized in that: The PCS system includes a full-power converter, a voltage stabilizing circuit, and a control circuit; The full-power converter controls the voltage and current of the electricity generated by the wind power generation system and the photovoltaic power generation system through controllable AC-DC-AC and DC-AC circuits to achieve the voltage and current required for grid connection, thereby achieving grid connection; The voltage stabilizing circuit passes the electricity generated by the electrochemical energy storage system through the voltage stabilizing circuit to meet the power supply requirements, and then supplies it to the electric load system; The control circuit controls the charge and discharge time of the electrochemical energy storage system, the operation time of the heat storage system, the power generation conditions of the wind power generation system and the photovoltaic power generation system, and the operation conditions of the load system.

7. The system according to claim 1, characterized in that: The mode switching system dynamically switches the wind-solar hybrid storage system into four different operating conditions, namely, no energy storage operating condition, single electrochemical energy storage operating condition, single thermal energy storage operating condition, and combined heat and power storage operating condition, to explore the system changes under different operating conditions.

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