Teaching experiment platform and method for simulating participation of hybrid energy storage system in power grid frequency modulation

Abstract

The invention is suitable for the technical field of electric energy storage, and provides a teaching experiment platform and method for simulating a hybrid energy storage system to participate in power grid frequency modulation, the teaching experiment platform comprises a power grid, the power grid is electrically connected with an energy storage unit through an AC bus, and the output end of the power grid is also electrically connected with a simulation power generation unit. The output end of the simulation power generation unit is electrically connected with the alternating current bus, a first switch is arranged between the simulation power generation unit and the alternating current bus, and the energy storage unit at least comprises a flywheel energy storage unit, a battery energy storage unit and a simulation load unit which are connected in parallel through the alternating current bus; according to the teaching experiment platform and method for simulating the participation of the hybrid energy storage system in the power grid frequency modulation, the distributed power generation units and various types of energy storage devices are configured, and the various energy storage devices can be flexibly combined through the alternating current bus, so that various different types of microgrids are constructed; and diversified scenes are provided for technical research, equipment monitoring and personnel training of the alternating current bus.

Description

Technical Field

[0001] This invention belongs to the field of power energy storage and smart grid technology, and in particular relates to a teaching experimental platform and method for simulating a hybrid energy storage system participating in grid frequency regulation. Background Technology

[0002] Existing experimental platforms are mostly single-function and lack simulation of generator inertia and real load characteristics, making it difficult to comprehensively and realistically reflect the synergistic frequency regulation effect of hybrid energy storage in complex power grid environments. With the continuous increase in the penetration rate of intermittent renewable energy sources such as wind and solar power in the power system, the equivalent rotational inertia of the power grid has significantly decreased, and the random fluctuations in renewable energy output exacerbate grid frequency deviations, placing higher demands on the frequency regulation capabilities of the power system. Hybrid energy storage systems, with their complementary characteristics in power response speed and capacity duration among different energy storage units, have become a key technological direction for solving the power grid frequency regulation problem. The effectiveness of their synergistic frequency regulation strategy directly determines the stability of the power grid frequency and the reliability of power supply.

[0003] However, current experimental platforms used to verify the synergistic frequency regulation effect of hybrid energy storage have significant technical limitations and are difficult to match the testing requirements in complex power grid environments.

[0004] As described in Chinese Patent Publication No. CN120978821A, a method and system for coordinated frequency regulation of a hybrid flywheel energy storage system are disclosed. The method includes: constructing a hybrid energy storage array composed of a power-type flywheel array and an energy-type flywheel array, responsible for millisecond-level frequency support and second-level frequency recovery, respectively; designing a two-layer coordinated control structure, where the upper layer performs total power allocation and coordination based on grid frequency deviation and rate of change, and the lower layer executes commands through dual closed-loop control of speed and current; introducing a state manifold design based on Lyapunov stability theory; and employing an adaptive gain adjustment mechanism to dynamically adjust the flywheel output according to the real-time characteristics of frequency disturbances, achieving dynamic coordinated scheduling of the two types of flywheels under frequency fluctuations at different time scales. This invention effectively improves the adaptive capability, response speed, and control accuracy of the hybrid flywheel system to complex frequency disturbances, enhancing the frequency stability of the power grid.

[0005] This system focuses on testing the independent operating characteristics of a single energy storage device. It can only simulate the charging and discharging behavior of a single type of energy storage such as battery energy storage or flywheel energy storage. It cannot build a collaborative control experimental environment for multiple types of energy storage units. As a result, the core functions of each unit in the hybrid energy storage system, such as power allocation strategy and response priority coordination, cannot be effectively verified, and the experimental results deviate significantly from the actual application scenario.

[0006] Furthermore, existing experimental platforms suffer from poor functional scalability and compatibility. For example, Chinese patent CN120855416A describes a method and system for predicting frequency regulation commands for hybrid energy storage-assisted thermal power units. This involves acquiring the original frequency regulation command sequence, performing dynamic phase compensation, calculating phase reference values, performing nonlinear correction, obtaining a first correction signal, enhancing the information entropy gradient of sampling points, enhancing the first correction signal to obtain a second correction signal, and performing chaotic time-series reconstruction to obtain a third correction signal. The chaotic time-series reconstruction includes constructing a time delay embedding space to map to a high-dimensional phase space and calculating the local Lyapunov exponent. However, this method uses a fixed hardware architecture and control logic, making it difficult to flexibly connect different types of energy storage units to adjust grid simulation parameters according to testing requirements.

[0007] In summary, there is currently a lack of a comprehensive, realistic, and flexibly expandable experimental platform that can accurately simulate the inertia characteristics, dynamic loads, and multiple disturbance conditions of complex power grids, and support the coordinated control and comprehensive benefit assessment of multiple types of hybrid energy storage. Summary of the Invention

[0008] This patent provides a teaching experimental platform and method for simulating the participation of a hybrid energy storage system in grid frequency regulation. It configures distributed generation units and various types of energy storage devices, and enables flexible combination of various energy storage devices through an AC bus to construct various types of microgrids, providing diverse scenarios for AC bus technology research, equipment monitoring, and personnel training.

[0009] To overcome the shortcomings of existing technologies, this invention provides a teaching experimental platform for simulating a hybrid energy storage system participating in grid frequency regulation, including a power grid, which is electrically connected to a flywheel energy storage unit, a battery energy storage unit and a simulated load unit via an AC bus.

[0010] The technical solution adopted by the present invention to solve its technical problem is as follows: the output end of the power grid is also electrically connected to a simulated power generation unit equipped with a frequency converter, the output end of the simulated power generation unit is electrically connected to the AC bus, and a first switch is provided between the simulated power generation unit and the AC bus; the flywheel energy storage unit, the battery energy storage unit, the simulated load unit, the frequency converter and the first switch are all communicatively connected to the host computer system.

[0011] Furthermore, the output terminal of the power grid is electrically connected to the frequency converter, the output terminal of the frequency converter is electrically connected to the input terminal of the asynchronous motor, the output terminal of the asynchronous motor is mechanically connected to the input terminal of the permanent magnet synchronous generator, the output terminal of the permanent magnet synchronous generator is connected to the AC bus, and the simulated power generation unit also includes a resistor box electrically connected to the AC bus.

[0012] Furthermore, the flywheel energy storage unit includes a flywheel motor, which is electrically connected to the AC bus via a DC / AC bidirectional power electronic converter.

[0013] Furthermore, the battery energy storage unit includes a battery pack and a battery management system, wherein the battery pack is electrically connected to the AC bus via an AC / DC energy storage converter.

[0014] Furthermore, the simulated load unit is a three-phase programmable load, which consists of multiple independent resistor branches and inductor branches, and each branch is electrically connected to the AC bus via a power electronic switch.

[0015] Furthermore, the platform also includes a second switch, which is located at the end of the AC bus away from the power grid, and the AC bus is electrically connected to the flywheel energy storage unit, the battery energy storage unit and the simulated load unit through the second switch. The second switch is also communicatively connected to the host computer system.

[0016] Furthermore, the platform also includes a third energy storage unit, which is located at the end of the second switch away from the AC bus. The third energy storage unit is communicatively connected to the host computer system and can be a physical energy storage unit or a virtual energy storage unit.

[0017] This invention also provides an experimental method for a teaching experimental platform that simulates a hybrid energy storage system participating in grid frequency regulation, comprising the following steps: S1: Power grid output current, platform enters standby self-test state; S2: Based on the target experiment type, select the corresponding experimental function branch and execute the corresponding experimental operation. The experimental function branch includes at least one of the following: power grid frequency regulation experiment branch, energy storage charging and discharging condition experiment branch, and simulated energy storage system experiment branch. S3: Complete the target experiment and obtain experimental data.

[0018] Furthermore, when the experimental function branch in step S2 is the power grid frequency regulation experimental branch, the experimental execution steps include: S21: Select the generator frequency to be simulated; S31: Select to connect to the analog power generation unit; S41: Select either the flywheel energy storage unit or the battery energy storage unit that needs to be connected to the microgrid; S51: The teaching experimental platform controls the inverter output to simulate generator power generation, switches the resistor box to simulate power generation fluctuations, controls the simulated load unit to simulate grid-side fluctuations, and controls the second switch to connect the simulated generator unit, flywheel energy storage unit, and battery energy storage unit to the microgrid to complete the grid frequency regulation experiment of hybrid energy storage coordinated control.

[0019] Furthermore, when the experimental function branch in step S2 is the energy storage charging and discharging condition experimental branch, the experimental execution steps include: S22: Determine the operating conditions that need to be simulated; S32: Select an energy storage application method, wherein the energy storage application method includes flywheel energy storage unit charging and discharging, battery energy storage unit charging and discharging, or hybrid energy storage unit charging and discharging; S42: Through the teaching experimental platform, control the DC / AC side bidirectional power electronic converter, the AC / DC side bidirectional power electronic converter and the AC / DC energy storage converter to realize the switching of energy storage application mode, and display the response characteristics, power output waveform and status parameters under different operating conditions.

[0020] Furthermore, when the experimental function branch in step S2 is a simulated energy storage system experimental branch, the experimental execution steps include: S23: When the third energy storage unit is a virtual energy storage unit, select the third energy storage unit to simulate it as a supercapacitor energy storage system, a fuel cell energy storage system, or a flow battery energy storage system. S33: Configure the operating parameters and control strategy of the third energy storage unit; S43: Configure parameters and operating strategies through the additional energy storage unit controller integrated into the host computer system, and output the power response, dynamic characteristics, and performance differences of the energy storage system through the simulation system to complete the virtual-real combined power grid frequency regulation experiment.

[0021] The beneficial effects of this invention are: 1. This AC bus platform based on flywheel and battery hybrid energy storage allows learners to intuitively understand the conversion principle of flywheel through the charging and discharging of flywheel batteries, breaking through the theoretical knowledge barrier; the teaching experimental platform can collect and display core parameters such as flywheel speed, power response time, and charging and discharging efficiency in real time, realizing the quantitative analysis and practical training of flywheel characteristics; 2. By simulating scenarios such as sudden changes in grid load and fluctuations in power generation, the application strategies of flywheels in frequency regulation and transient power support are trained, which are in line with actual engineering needs; the comparison is clear: running in parallel with the lead-acid battery branch, the differences between the characteristics of flywheels ("high power density and fast response") and batteries ("high energy density and long duration") can be intuitively compared, deepening the understanding of the synergy of hybrid energy storage. Attached Figure Description

[0022] Figure 1 The experimental platform topology diagram in Embodiment 1 provided by this invention; Figure 2 This is a topology diagram of the experimental platform in Embodiment 2 provided by the present invention; Figure 3 This is a topology diagram of the experimental platform in Embodiment 3 provided by the present invention; Figure 4 The topology diagram of the simulated load unit provided by this invention; Figure 5 This is a flowchart of the teaching experiment in Embodiment 1 provided by the present invention; Figure 6 This is a flowchart of the teaching experiment in Embodiment 2 provided by the present invention; Figure 7 This is a flowchart of the teaching experiment in Embodiment 3 of the present invention.

[0023] In the diagram: 1. Power grid; 2. AC bus; 31. Flywheel energy storage unit; 311. Flywheel motor; 312. DC / AC bidirectional power electronic converter; 313. AC / DC bidirectional power electronic converter; 32. Battery energy storage unit; 321. Battery pack; 322. AC / DC energy storage converter; 323. Battery management system; 33. Simulated load unit; 331. Resistor branch; 332. Inductor branch; 333. Power electronic switch; 34. Third energy storage unit; 4. Simulated power generation unit; 41. Frequency converter; 42. Asynchronous motor; 43. Permanent magnet synchronous generator; 44. Resistor box; 5. First switch; 6. Host computer system; 7. Second switch. Detailed Implementation

[0024] This specific embodiment is merely an explanation of the present invention and is not intended to limit the invention. After reading this specification, those skilled in the art can make modifications to this embodiment without contributing any inventive element, but such modifications are protected by patent law as long as they fall within the scope of the claims of the present invention.

[0025] It should be noted that when a component is referred to as being "fixed to" or "set on" another component, it can be directly on or indirectly on that other component. When a component is referred to as being "connected to" another component, it can be directly connected to or indirectly connected to that other component.

[0026] It should be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the present invention.

[0027] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of some inventions, "a plurality of" means two or more, unless otherwise explicitly specified.

[0028] Example 1: This embodiment provides: a teaching experimental platform and method for simulating the participation of a hybrid energy storage system in grid frequency regulation, referring to... Figure 1 , 4The system is understood as follows: Grid 1 serves as the voltage and frequency reference for the platform, or as the power source for the simulated power generation unit 4. Grid 1 is electrically connected to the flywheel energy storage unit 31, battery energy storage unit 32, and simulated load unit 33 via AC bus 2. AC bus 2 acts as the hub for energy collection and distribution in the entire energy storage system, and is controlled by the host computer system 6. The output of grid 1 is also electrically connected to the simulated power generation unit 4, which simulates the operating characteristics of a traditional synchronous generator. The output of the simulated power generation unit 4 is electrically connected to AC bus 2. The simulated power generation unit 4 includes a frequency converter 41. The output of grid 1 is electrically connected to the frequency converter 41, which is communicatively connected to the host computer system 6. The output of the frequency converter 41 is electrically connected to the input of the asynchronous motor 42, and the output of the asynchronous motor 42 is mechanically connected to the input of the permanent magnet synchronous generator 43. The output of the permanent magnet synchronous generator 43 is connected to AC bus 2. The frequency converter 41 receives commands from the platform to adjust the speed of the asynchronous motor 42, thereby controlling the active power output of the synchronous generator 43. This simulates the power fluctuations of the prime mover and the rotational inertia of the generator set. The simulated power generation unit 4 also includes a resistor box 44 electrically connected to the AC bus 2. The connection and disconnection of the resistor box 44 simulates the step fluctuations in renewable energy output. By changing the resistance value, it simulates the step changes in load, creating a frequency disturbance source for the system. In the simulated power generation unit 4, the input terminal of the frequency converter 41 is connected to the power grid 1, and its output terminal drives the asynchronous motor 42. The asynchronous motor 42 is mechanically connected to the synchronous generator 43 through a coupling, and the output terminal of the synchronous generator 43 is directly connected to the AC bus 2. Electricity drives the asynchronous motor 42 via the frequency converter 41, which in turn drives the synchronous generator 43 to rotate and generate electricity. The core function of this unit is to simulate the inertial response and primary frequency regulation characteristics of a real power system. By adjusting the output of the frequency converter 41, the input power of the asynchronous motor 42 can be changed, simulating power fluctuations such as those from wind power and photovoltaic power, or the regulation process of conventional thermal power. Specifically, the resistor box 44 connected in parallel to the outlet of the synchronous generator 43 is used to simulate sudden loads on the generator side itself or power fluctuations of the prime mover.

[0029] A first switch 5 is installed between the simulated power generation unit 4 and the AC bus 2. The flywheel energy storage unit 31 includes a flywheel motor 311, which is electrically connected to the AC bus 2 via a DC / AC bidirectional power electronic converter 312 and an AC / DC bidirectional power electronic converter 313. The DC / AC bidirectional power electronic converter 312 and the AC / DC bidirectional power electronic converter 313 together form a back-to-back converter system. The AC / DC bidirectional power electronic converter 313 is used to control the power transfer between the flywheel energy storage device and the AC bus. The DC / AC bidirectional power electronic converter 312 is used to control the torque and speed of the flywheel energy storage motor. The flywheel energy storage unit 31, with its fast response characteristics, focuses on absorbing or releasing high-frequency, short-term power components, effectively suppressing rapid frequency changes and instantaneous fluctuations. The battery energy storage unit 32 includes a battery pack 321 and a battery management system 323. The battery pack 321 provides a large energy density; the battery pack 321 is electrically connected to the AC bus 2 via an AC / DC energy storage converter 322. The battery management system 323 is responsible for battery status monitoring and protection; the AC / DC energy storage converter 322 realizes bidirectional conversion between DC power and AC bus 2 power. This unit is mainly used to compensate for low-frequency, long-term power deviations and perform energy balance. The battery energy storage unit 32, with its high energy density, is mainly responsible for dealing with low-frequency, long-term power imbalances and making up for continuous energy gaps, acting as an "energy pool" to maintain long-term frequency stability. Together with the flywheel energy storage unit 31, it forms a frequency regulation system with complementary advantages of high power density and high energy density through coordinated control, jointly undertaking the frequency regulation task. The analog load unit 33 is a three-phase programmable load, consisting of multiple independent resistor branches 331 and inductor branches 332, each branch being electrically connected to AC bus 2 via a power electronic switch 333. The simulated load unit is a three-phase programmable RL load, consisting of multiple sets of resistor and inductor branches that can be independently switched by power electronic switches 333. Through platform programming, it can simulate the dynamic changes of linear loads in the actual power grid, creating system power deficits or surpluses to stimulate frequency regulation. The simulated load unit 33 can accurately simulate the complex changes in grid user loads, i.e., grid-side fluctuations. Through programming settings, it can generate various load curves such as step, ramp, or random fluctuations, realistically reproducing the load uncertainties faced by the power grid in actual operation, thereby testing the system's frequency stability. The flywheel energy storage unit 31, battery energy storage unit 32, simulated load unit 33, simulated generator unit 4, and the first switch 5 are all communicatively connected to the host computer system 6. The host computer system 6 is used to send control commands to each unit, receive operating data, and coordinate the flywheel energy storage unit 31 and battery energy storage unit 32 to cooperate in grid-connected or islanded operation modes to participate in grid frequency regulation. The entire platform's operation mode is flexibly controlled by the host computer system 6, enabling the conversion of grid connection mode, and is used to study the control strategies of hybrid energy storage under different operating conditions.The frequency converter and programmable load that generate fluctuations, the flywheel and battery energy storage converter that perform frequency regulation, and the switches that change the topology are all controlled by the host computer system 6 via a communication bus. This system is the host computer system of the platform. It collects all data, executes and distributes various advanced control algorithms, and fully reproduces the entire dynamic process of energy storage participating in fluctuation regulation, from fluctuation generation and frequency sensing to energy storage coordinated regulation, providing strong experimental support for teaching and scientific research. When an experiment is required, the grid 1 first outputs current, and the platform enters a standby self-test state. After the platform enters the standby self-test state, the energy storage charging and discharging experiment can be conducted. First, the operating conditions to be simulated are determined. After the operating conditions are determined, the energy storage application mode is selected as either the charging and discharging of the flywheel energy storage unit 31, the charging and discharging of the battery energy storage unit 32, or a combination of both. After the energy storage application mode is selected, S42: the host computer system 6 controls the DC / AC side bidirectional power electronic converter 312, the AC / DC side bidirectional power electronic converter 313, and the AC / DC energy storage converter 322 to switch the energy storage application mode. The host computer system 6 displays the response characteristics, power output waveforms, and status parameters of different operating conditions. By recording the waveforms and status parameters, experimental data can be obtained. During the teaching process, students can set different operating conditions through the teaching experimental platform. For example, after the system is powered on and completes its self-test, the flywheel energy storage unit 31 can be controlled to perform rapid charging and discharging to simulate grid frequency regulation, while the battery energy storage unit 32 can be controlled to perform charging and discharging for a longer period of time to balance energy. By observing the response characteristics, power output waveforms, and state parameters of the two energy storage devices under different commands, such as flywheel speed and battery state of charge (SOC), students can intuitively understand the characteristics of high power density and fast response of flywheel energy storage and high energy density of battery energy storage, as well as their complementary advantages in hybrid applications.

[0030] Example 2, please refer to Figure 2 and Figure 6Based on Embodiment 1, the platform further includes a second switch 7, which is located at the end of the AC bus 2 furthest from the power grid 1 and is communicatively connected to the host computer system 6. The second switch 7 is used to selectively switch the flywheel energy storage unit 31, battery energy storage unit 32, and simulated load unit 33 between the AC bus 2 and the power grid 1, thereby constructing two typical operating conditions. In this embodiment, the host computer system 6 also includes a mode switching module, configured to: in grid-connected operation mode, control the switch to connect each unit to the power grid and perform frequency modulation control based on frequency deviation; in islanded operation mode, control the switch to disconnect each unit from the power grid 1, forming an islanded microgrid, and perform control aimed at stabilizing the voltage and frequency of the AC bus 2. The flywheel energy storage unit 31 and the battery energy storage unit 32 can be selectively connected in parallel to the AC bus 2 via the second switch 7 to construct either a grid-connected operation mode or an islanded operation mode. When an experiment is required, the platform enters a standby self-test state and can then conduct a grid frequency regulation experiment. Step S21 is then implemented: selecting the generator frequency to be simulated. After selection, step S31 is implemented: selecting the simulated generator unit 4 to be connected. Then, the flywheel energy storage unit 31 or the battery energy storage unit 32 to be connected to the microgrid is selected. After selection, step S51 is implemented: the frequency converter 41 is controlled by the teaching experimental platform to output simulated generator power generation; the switching resistor box 44 is used to simulate power generation fluctuations; the simulated load unit 33 is controlled to simulate grid-side fluctuations; and the second switch 7 is controlled to connect the simulated generator unit 4, the flywheel energy storage unit 31, or the battery energy storage unit 32 to the microgrid, thus completing the grid frequency regulation experiment for coordinated control of hybrid energy storage. After the experiment is completed, the experimental data is finally obtained.

[0031] Example 3, please refer to Figure 3 and Figure 7 Based on Embodiment 2, the platform further includes a third energy storage unit 34. The third energy storage unit 34 is located at the end of the second switch 7 furthest from the AC bus 2. The third energy storage unit 34 is communicatively connected to the host computer system 6. The third energy storage unit 34 can be a physical energy storage unit or a virtual energy storage unit. When an experiment is required, the platform enters a standby self-test state and can then perform a simulated energy storage system experiment. First, the third energy storage unit 34 is selected among the energy storage units. If the third energy storage unit 34 is a virtual energy storage unit, it is simulated as a supercapacitor energy storage system, a fuel cell energy storage system, or a flow battery energy storage system. Then, step S33 is implemented: configuring the operating parameters and control strategy of the third energy storage unit 34. Finally, the parameters and operating strategy are configured through the additional energy storage unit controller integrated in the host computer system 6. The power response, dynamic characteristics, and performance differences of the energy storage system are output through the simulation system to complete a combined virtual and real grid frequency regulation experiment.

[0032] Compared to the aforementioned embodiments, the core feature of this embodiment lies in further expanding the breadth of energy storage types and constructing a more comprehensive virtual-physical hybrid experimental environment. Based on the original flywheel and battery energy storage, the teaching experimental device integrates various other energy storage systems in a semi-physical simulation format, such as supercapacitor energy storage systems, fuel cell systems, or flow battery systems. These other energy storage systems are not all physical entities; some are virtual energy storage units simulated with high precision by a high-performance real-time simulator within the teaching experimental platform. These virtual units are logically connected to the AC or DC bus through their corresponding analog converter interfaces. Correspondingly, the host computer system 6 also integrates controllers for these additional energy storage units, used to set and adjust their operating parameters and control strategies. This "virtual-physical hybrid" architecture, where the teaching experimental device hardware and simulation platform software jointly constitute a semi-physical simulation platform, brings significant flexibility and scalability. With this multi-energy storage configuration, after the system is powered on and completes its self-test, students can overcome the limitations of physical equipment to study and compare various energy storage technologies, such as the inertial support of flywheels, the energy pool of batteries, the instantaneous power response of supercapacitors, and the dynamic characteristics and performance differences of continuous power generation from fuel cells. They can freely design and verify complex coordinated control strategies. For example, they can make power-type energy storage such as flywheel energy storage and supercapacitors work together to cope with high-frequency, short-term power fluctuations, and make energy-type energy storage such as batteries cope with medium- and low-frequency, long-term energy throughput. They can even introduce fuel cells as a long-term, stable backup power source, thereby constructing and optimizing a hybrid energy storage system covering multiple time scales from seconds to hours.

[0033] In summary, the teaching experimental platform and corresponding experimental methods for simulating hybrid energy storage systems participating in grid frequency regulation provided by the various embodiments of this invention possess outstanding teaching and training value, experimental scenarios closely aligned with engineering realities, and excellent functional scalability and compatibility. Specifically, this platform can not only collect and display core parameters such as flywheel speed, power response time, and battery SOC in real time, allowing learners to intuitively understand the flywheel's "high power density and fast response" and the battery's "high energy density and long range," but also... The platform leverages the unique characteristics of various energy storage technologies, including supercapacitors and fuel cells, through a hybrid virtual-physical architecture. This breaks down theoretical barriers and enables quantitative training on energy storage characteristics. Simultaneously, it accurately simulates complex operating conditions such as sudden changes in grid load and fluctuations in power generation, supporting switching between multiple operating modes, including grid connection and islanding. It replicates the inertial response and frequency regulation characteristics of real power systems, providing a real experimental platform for mastering engineering-grade energy storage frequency regulation schemes. Furthermore, the platform can flexibly expand from a basic flywheel-battery hybrid energy storage architecture to various types of hybrid virtual-physical energy storage systems. Experimental parameters can be adjusted and different energy storage units can be connected according to teaching and research needs. This satisfies both basic teaching and training requirements and supports research on complex hybrid energy storage collaborative control strategies, achieving full coverage of teaching and research scenarios. It provides strong equipment and methodological support for talent cultivation and technological research in the fields of power energy storage and smart grids.

[0034] It is understood that those skilled in the art can combine various implementation methods in the above embodiments under the guidance of the above examples to obtain technical solutions with multiple implementation methods.

[0035] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A teaching experimental platform simulating a hybrid energy storage system participating in grid frequency regulation, comprising a power grid (1), wherein the power grid (1) is electrically connected to a flywheel energy storage unit (31), a battery energy storage unit (32), and a simulated load unit (33) respectively via an AC bus (2), characterized in that: The output end of the power grid (1) is also electrically connected to the simulated power generation unit (4) equipped with a frequency converter (41). The output end of the simulated power generation unit (4) is electrically connected to the AC bus (2). A first switch (5) is provided between the simulated power generation unit (4) and the AC bus (2). The flywheel energy storage unit (31), the battery energy storage unit (32), the simulated load unit (33), the frequency converter (41) and the first switch (5) are all connected to the host computer system (6) for communication.

2. The teaching experimental platform for simulating a hybrid energy storage system participating in grid frequency regulation as described in claim 1, characterized in that, The output end of the power grid (1) is electrically connected to the frequency converter (41), the output end of the frequency converter (41) is electrically connected to the input end of the asynchronous motor (42), the output end of the asynchronous motor (42) is mechanically connected to the input end of the permanent magnet synchronous generator (43), the output end of the permanent magnet synchronous generator (43) is connected to the AC bus (2), and the simulated power generation unit (4) also includes a resistor box (44) electrically connected to the AC bus (2).

3. The teaching experimental platform for simulating a hybrid energy storage system participating in grid frequency regulation as described in claim 2, characterized in that, The flywheel energy storage unit (31) includes a flywheel motor (311), which is electrically connected to the AC bus (2) via a DC / AC bidirectional power electronic converter (312) and an AC / DC bidirectional power electronic converter (313).

4. The teaching experimental platform for simulating a hybrid energy storage system participating in grid frequency regulation as described in claim 2, characterized in that, The battery energy storage unit (32) includes a battery pack (321) and a battery management system (323). The battery pack (321) is electrically connected to the AC bus (2) through an AC / DC energy storage converter (322).

5. The teaching experimental platform for simulating a hybrid energy storage system participating in grid frequency regulation as described in claim 2, characterized in that, The simulated load unit (33) is a three-phase programmable load. The three-phase programmable load consists of multiple independent resistor branches (331) and inductor branches (332), and each branch is electrically connected to the AC bus (2) through a power electronic switch (333).

6. A teaching experimental platform for simulating hybrid energy storage systems participating in grid frequency regulation as described in any one of claims 1-5, characterized in that, The platform also includes a second switch (7), which is located at the end of the AC bus (2) away from the power grid (1). The AC bus (2) is electrically connected to the flywheel energy storage unit (31), the battery energy storage unit (32) and the simulated load unit (33) through the second switch (7). The second switch (7) is also connected to the host computer system (6) for communication.

7. The teaching experimental platform for simulating a hybrid energy storage system participating in grid frequency regulation as described in claim 6, characterized in that, The platform also includes a third energy storage unit (34), which is located at the end of the second switch (7) away from the AC bus (2). The third energy storage unit (34) is connected to the host computer system (6) for communication. The third energy storage unit (34) is a physical energy storage unit or a virtual energy storage unit.

8. The experimental method for a teaching experimental platform applied to simulating hybrid energy storage systems participating in grid frequency regulation as described in claim 7, characterized in that, Includes the following steps: S1: The power grid (1) outputs current, and the platform enters standby self-test state; S2: Based on the target experiment type, select the corresponding experimental function branch and execute the corresponding experimental operation. The experimental function branch includes at least one of the following: power grid frequency regulation experiment branch, energy storage charging and discharging condition experiment branch, and simulated energy storage system experiment branch. S3: Complete the target experiment and obtain experimental data.

9. A teaching experiment method for simulating a hybrid energy storage system participating in grid frequency regulation as described in claim 8, characterized in that, When the experimental function branch in step S2 is the power grid frequency regulation experimental branch, the experimental execution steps include: S21: Select the generator frequency to be simulated; S31: Select to connect to the analog power generation unit (4); S41: Select the flywheel energy storage unit (31) or battery energy storage unit (32) that needs to be connected to the microgrid. S51: The frequency converter (41) is controlled by the teaching experimental platform to output the simulated generator to generate electricity. The power generation fluctuation is simulated by switching the resistor box (44). The grid-side fluctuation is simulated by controlling the simulated load unit (33). The simulated generator unit (4) or flywheel energy storage unit (31) and battery energy storage unit (32) are connected to the microgrid by controlling the second switch (7) to complete the grid frequency regulation experiment of hybrid energy storage coordinated control.

10. The teaching experiment method for simulating a hybrid energy storage system participating in grid frequency regulation as described in claim 8, characterized in that, When the experimental function branch in step S2 is the energy storage charging and discharging condition experimental branch, the experimental execution steps include: S22: Determine the operating conditions that need to be simulated; S32: Select an energy storage application mode, wherein the energy storage application mode includes charging and discharging of flywheel energy storage unit (31), charging and discharging of battery energy storage unit (32) or charging and discharging of hybrid energy storage unit; S42: The teaching experimental platform controls the DC / AC side bidirectional power electronic converter (312), AC / DC side bidirectional power electronic converter (313) and AC / DC energy storage converter (322) to realize the switching of energy storage application mode, and displays the response characteristics, power output waveform and status parameters under different operating conditions.

11. The teaching experiment method for simulating a hybrid energy storage system participating in grid frequency regulation as described in claim 8, characterized in that, When the experimental function branch in step S2 is the simulated energy storage system experimental branch, the experimental execution steps include: S23: When the third energy storage unit (34) is a virtual energy storage unit, select the third energy storage unit (34) to simulate it as a supercapacitor energy storage system, a fuel cell energy storage system or a flow battery energy storage system; S33: Configure the operating parameters and control strategy of the third energy storage unit (34); S43: Configure parameters and operating strategies through the additional energy storage unit controller integrated by the host computer system (6), and output the power response, dynamic characteristics and performance differences of the energy storage system through the simulation system to complete the virtual and real grid frequency regulation experiment.

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