A method and apparatus for dynamically regulated hybrid energy storage power distribution

Abstract

The present application relates to the technical field of direct current micro-grid control, and specifically provides a mixed energy power distribution method and device for dynamic adjustment, comprising: determining a power change factor of a direct current micro-grid system based on a power change rate standard value of the direct current micro-grid system; determining a super capacitor power distribution coefficient based on the power change factor of the direct current micro-grid system; and determining reference output power of the super capacitor and a battery based on the super capacitor power distribution coefficient. The technical scheme provided by the present application realizes power fluctuation caused by system mutation, reasonably distributes power transient component and steady component, respectively inputs / outputs to the super capacitor and the battery, and reduces direct current bus voltage fluctuation on the basis of uniform power distribution, thereby enhancing system stability.

Description

Technical Field

[0001] This invention relates to the field of DC microgrid control technology, specifically to a hybrid energy storage power distribution method and device for dynamic adjustment. Background Technology

[0002] In recent years, with the increasing scale of new energy grid connection, the optimization of energy quality and energy system has become particularly important. Microgrids are small, independent power networks that can operate independently. Compared with AC microgrids, DC microgrids have advantages such as less reactive power. However, due to the intermittency of renewable energy systems and the dynamic changes in load power, the stable operation of DC microgrids in islanded mode is seriously threatened, which may lead to system power imbalance and bus voltage instability. Appropriate energy storage devices are required to maintain the power balance of the system, which increases the demand for reliable and effective coordination strategies.

[0003] In DC microgrids, batteries are the most widely used energy storage device. Battery energy storage systems can be used to compensate for power fluctuations from renewable energy sources and have high energy density, but they are not suitable for high-frequency power output and transient fluctuations. Supercapacitors, as power storage devices, have fast response speeds and complement batteries to some extent. Therefore, a hybrid energy storage system (HESS) composed of batteries and supercapacitors can cope with the complex and variable power demands of the microgrid system through reasonable control strategies, while mitigating fluctuations in bus voltage, a crucial indicator of DC microgrid stability. However, current hybrid energy storage power allocation strategies for dynamic adjustment face various problems and challenges. Summary of the Invention

[0004] To overcome the above-mentioned shortcomings, this invention proposes a method and apparatus for dynamically adjusting hybrid energy storage power allocation.

[0005] Firstly, a method for dynamically adjusting hybrid energy storage power allocation is provided, the method comprising: Determine the power variation factor of a DC microgrid system based on the standard value of the power variation rate of a DC microgrid system; Determining the power allocation coefficient of supercapacitors based on the power variation factor of DC microgrid systems; The reference output power of the supercapacitor and battery is determined based on the supercapacitor power allocation factor.

[0006] Preferably, the standard value for the power change rate of the DC microgrid system is as follows:

[0007] In the above formula, This represents the standard value for the power change rate of a DC microgrid system. This represents the total load power at the current moment. for Total load power before time, To rewind time, This is the normalization coefficient.

[0008] Furthermore, the backtracking time is 0.1 seconds.

[0009] Preferably, the power variation factor of the DC microgrid system is as follows:

[0010] In the above formula, This represents the standard value for the power change rate of a DC microgrid system. The power variation factor of a DC microgrid system. This is a preset limit value.

[0011] Furthermore, the preset limit value is 0.1.

[0012] Furthermore, the power distribution coefficient of the supercapacitor is as follows:

[0013] In the above formula, This refers to the power distribution factor of the supercapacitor. This refers to the current moment.

[0014] Furthermore, the reference output power of the supercapacitor is as follows:

[0015] In the above formula, This is the reference output power of the supercapacitor. This represents the total output power of the energy storage system.

[0016] Furthermore, the reference output power of the battery is as follows:

[0017] In the above formula, This is the reference output power of the battery.

[0018] Secondly, a hybrid energy storage power distribution device for dynamic adjustment is provided, the hybrid energy storage power distribution device for dynamic adjustment comprising: The first determining module is used to determine the power change factor of the DC microgrid system based on the standard value of the power change rate of the DC microgrid system. The second determining module is used to determine the supercapacitor power allocation coefficient based on the power change factor of the DC microgrid system. The third determining module is used to determine the reference output power of the supercapacitor and the battery based on the supercapacitor power allocation coefficient.

[0019] Preferably, the standard value for the power change rate of the DC microgrid system is as follows:

[0020] In the above formula, This represents the standard value for the power change rate of a DC microgrid system. This represents the total load power at the current moment. for Total load power before time, To rewind time, This is the normalization coefficient.

[0021] Furthermore, the backtracking time is 0.1 seconds.

[0022] Preferably, the power variation factor of the DC microgrid system is as follows:

[0023] In the above formula, This represents the standard value for the power change rate of a DC microgrid system. The power variation factor of a DC microgrid system. This is a preset limit value.

[0024] Furthermore, the preset limit value is 0.1.

[0025] Furthermore, the power distribution coefficient of the supercapacitor is as follows:

[0026] In the above formula, This refers to the power distribution factor of the supercapacitor. This refers to the current moment.

[0027] Furthermore, the reference output power of the supercapacitor is as follows:

[0028] In the above formula, This is the reference output power of the supercapacitor. This represents the total output power of the energy storage system.

[0029] Furthermore, the reference output power of the battery is as follows:

[0030] In the above formula, This is the reference output power of the battery.

[0031] Thirdly, a computer device is provided, comprising: one or more processors; The processor is used to store one or more programs; When the one or more programs are executed by the one or more processors, the hybrid energy storage power allocation method for dynamic adjustment is implemented.

[0032] Fourthly, a computer-readable storage medium is provided having a computer program stored thereon, wherein when the computer program is executed, it implements the aforementioned hybrid energy storage power allocation method for dynamic adjustment.

[0033] The above-described technical solutions of the present invention have at least one or more of the following beneficial effects: This invention provides a method and apparatus for dynamically adjusting hybrid energy storage power allocation, comprising: determining the power variation factor of a DC microgrid system based on a standard value of the power variation rate of the DC microgrid system; determining the supercapacitor power allocation coefficient based on the power variation factor of the DC microgrid system; and determining the reference output power of the supercapacitor and the battery based on the supercapacitor power allocation coefficient. The technical solution provided by this invention determines the system disturbance type based on the standard value of the power variation rate of the DC microgrid system. When a large disturbance occurs, the instantaneous fluctuating power is allocated to the supercapacitor according to a sinusoidal trend, and the steady-state power is allocated to the battery. When a small disturbance occurs, only the battery participates in power allocation. A voltage stabilization mechanism is added to reduce the bus voltage deviation. This achieves reasonable allocation of transient and steady-state power components to the supercapacitor and battery respectively, and addresses the bus voltage deviation during source-load changes, reducing DC bus voltage fluctuations on the basis of uniform power allocation and enhancing system stability. Attached Figure Description

[0034] Figure 1 This is a schematic flowchart of the main steps of the hybrid energy storage power allocation method for dynamic adjustment according to an embodiment of the present invention; Figure 2 This is a load power fluctuation curve diagram according to an embodiment of the present invention; Figure 3 This is a bus voltage fluctuation curve diagram according to an embodiment of the present invention; Figure 4 This is a schematic diagram of the allocation parameters according to an embodiment of the present invention; Figure 5 This is a simulation result diagram of the output power of the battery and supercapacitor in an embodiment of the present invention. Detailed Implementation

[0035] The specific embodiments of the present invention will be further described in detail below with reference to the accompanying drawings.

[0036] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0037] Example 1 See appendix Figure 1 , Figure 1 This is a schematic flowchart illustrating the main steps of a dynamically adjustable hybrid energy storage power allocation method according to an embodiment of the present invention. Figure 1 As shown, the hybrid energy storage power allocation method for dynamic adjustment in this embodiment of the invention mainly includes the following steps: Step S101: Determine the power variation factor of the DC microgrid system based on the standard value of the power variation rate of the DC microgrid system; Step S102: Determine the supercapacitor power allocation coefficient based on the power variation factor of the DC microgrid system; Step S103: Determine the reference output power of the supercapacitor and battery based on the supercapacitor power allocation coefficient.

[0038] In this embodiment, the standard value of the power change rate of the DC microgrid system is as follows:

[0039] In the above formula, This represents the standard value for the power change rate of a DC microgrid system. This represents the total load power at the current moment. for Total load power before time, To rewind time, This is the normalization coefficient.

[0040] In one implementation, the backtracking time is 0.1 seconds.

[0041] In this embodiment, the power variation factor of the DC microgrid system is as follows:

[0042] In the above formula, This represents the standard value for the power change rate of a DC microgrid system. The power variation factor of a DC microgrid system. This is a preset limit value.

[0043] In one implementation, the preset limit value is 0.1.

[0044] In one embodiment, the supercapacitor power distribution coefficient is as follows:

[0045] In the above formula, This refers to the power distribution factor of the supercapacitor. This refers to the current moment.

[0046] In one embodiment, the reference output power of the supercapacitor is as follows:

[0047] In the above formula, This is the reference output power of the supercapacitor. This represents the total output power of the energy storage system.

[0048] In one embodiment, the reference output power of the battery is as follows:

[0049] In the above formula, This is the reference output power of the battery.

[0050] To evaluate the performance of the sinusoidal motion trajectory control strategy, the load power was suddenly increased or decreased at different locations, and the photovoltaic output power was increased from a constant output of 2kW to 4kW. The load power fluctuations were as follows: Figure 2 As shown, For load power, Photovoltaic power, bus voltage Fluctuation situation as follows Figure 3 As shown; the allocation parameters are as follows Figure 4 As shown.

[0051] Depend on Figure 2 , 3 As shown in section 4, in the period of 0-0.4s, the photovoltaic output is higher than the load power. At this time, the bus voltage is maintained at a stable value of around 250V, and the energy storage system charging capacity is maintained at 2kW. In this charging mode, only the battery participates in power storage, while the supercapacitor does not participate in system power regulation.

[0052] At 0.4s, 0.8s, and 1.2s, the PCR factor during the sudden change in load power exceeded the limit value ±0.1, falling within the large disturbance range. The method of this invention was invoked, with the supercapacitor providing the transient component of the system's required power and slowly decreasing it to 0, while the battery provided the steady-state component of the system's required power, ensuring that the bus voltage quickly returned to a stable value of 250V within 0.03s after a brief fluctuation. At 1.6s, the PCR factor did not exceed the limit value ±0.1, falling within the small disturbance range. Only the battery provided the system's required power, ensuring that the bus voltage quickly returned to a stable value of 250V within 0.02s after a 0.7V fluctuation. The supercapacitor's participation in the transient response was 0.2s, and the output power of the battery and supercapacitor were as follows... Figure 5 As shown.

[0053] The above simulation analysis shows that during load power fluctuations, DC microgrids may experience system power imbalances and DC bus voltage fluctuations. This invention can respond quickly by determining the optimal strategy selection based on the system PCR factor during power surges, and promptly complete system power coordination and bus voltage fluctuation adjustment.

[0054] Example 2 Based on the same inventive concept, the present invention also provides a hybrid energy storage power distribution device for dynamic adjustment, the hybrid energy storage power distribution device for dynamic adjustment comprising: The first determining module is used to determine the power change factor of the DC microgrid system based on the standard value of the power change rate of the DC microgrid system. The second determining module is used to determine the supercapacitor power allocation coefficient based on the power change factor of the DC microgrid system. The third determining module is used to determine the reference output power of the supercapacitor and the battery based on the supercapacitor power allocation coefficient.

[0055] Preferably, the standard value for the power change rate of the DC microgrid system is as follows:

[0056] In the above formula, This represents the standard value for the power change rate of a DC microgrid system. This represents the total load power at the current moment. for Total load power before time, To rewind time, This is the normalization coefficient.

[0057] Furthermore, the backtracking time is 0.1 seconds.

[0058] Preferably, the power variation factor of the DC microgrid system is as follows:

[0059] In the above formula, This represents the standard value for the power change rate of a DC microgrid system. The power variation factor of a DC microgrid system. This is a preset limit value.

[0060] Furthermore, the preset limit value is 0.1.

[0061] Furthermore, the power distribution coefficient of the supercapacitor is as follows:

[0062] In the above formula, This refers to the power distribution factor of the supercapacitor. This refers to the current moment.

[0063] Furthermore, the reference output power of the supercapacitor is as follows:

[0064] In the above formula, This is the reference output power of the supercapacitor. This represents the total output power of the energy storage system.

[0065] Furthermore, the reference output power of the battery is as follows:

[0066] In the above formula, This is the reference output power of the battery.

[0067] Example 3 Based on the same inventive concept, this invention also provides a computer device, which includes a processor and a memory. The memory stores a computer program, which includes program instructions. The processor executes the program instructions stored in the computer storage medium. The processor may be a Central Processing Unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. It is the computing and control core of the terminal, and is suitable for implementing one or more instructions. Specifically, it is suitable for loading and executing one or more instructions from the computer storage medium to implement corresponding method flows or corresponding functions, thereby implementing the steps of a dynamically adjustable hybrid energy storage power allocation method in the above embodiments.

[0068] Example 4 Based on the same inventive concept, this invention also provides a storage medium, specifically a computer-readable storage medium (Memory), which is a memory device in a computer device used to store programs and data. It is understood that the computer-readable storage medium here can include both the built-in storage medium in the computer device and extended storage media supported by the computer device. The computer-readable storage medium provides storage space that stores the terminal's operating system. Furthermore, this storage space also stores one or more instructions suitable for loading and execution by a processor. These instructions can be one or more computer programs (including program code). It should be noted that the computer-readable storage medium here can be high-speed RAM or non-volatile memory, such as at least one disk storage device. The processor can load and execute one or more instructions stored in the computer-readable storage medium to implement the steps of the dynamically adjustable hybrid energy storage power allocation method in the above embodiments.

[0069] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0070] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0071] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0072] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0073] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the specific implementation of the present invention. Any modifications or equivalent substitutions that do not depart from the spirit and scope of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. A method for dynamically adjusting hybrid energy storage power allocation, characterized in that, The method includes: Determine the power variation factor of a DC microgrid system based on the standard value of the power variation rate of a DC microgrid system; Determining the power allocation coefficient of supercapacitors based on the power variation factor of DC microgrid systems; The reference output power of the supercapacitor and battery is determined based on the supercapacitor power allocation factor.

2. The method as described in claim 1, characterized in that, The standard value for the power change rate of the DC microgrid system is as follows: In the above formula, This represents the standard value for the power change rate of a DC microgrid system. This represents the total load power at the current moment. for Total load power before time, To rewind time, This is the normalization coefficient.

3. The method as described in claim 2, characterized in that, The backtracking time is 0.1 seconds.

4. The method as described in claim 1, characterized in that, The power variation factor of the DC microgrid system is as follows: In the above formula, This represents the standard value for the power change rate of a DC microgrid system. The power variation factor of a DC microgrid system. This is a preset limit value.

5. The method as described in claim 4, characterized in that, The preset limit value is 0.

1.

6. The method as described in claim 4, characterized in that, The supercapacitor power allocation coefficient is as follows: In the above formula, This refers to the power distribution factor of the supercapacitor. This refers to the current moment.

7. The method as described in claim 6, characterized in that, The reference output power of the supercapacitor is as follows: In the above formula, This is the reference output power of the supercapacitor. This represents the total output power of the energy storage system.

8. The method as described in claim 7, characterized in that, The reference output power of the battery is as follows: In the above formula, This is the reference output power of the battery.

9. A hybrid energy storage power distribution device for dynamic adjustment, characterized in that, The device includes: The first determining module is used to determine the power change factor of the DC microgrid system based on the standard value of the power change rate of the DC microgrid system. The second determining module is used to determine the supercapacitor power allocation coefficient based on the power change factor of the DC microgrid system. The third determining module is used to determine the reference output power of the supercapacitor and the battery based on the supercapacitor power allocation coefficient.

10. The apparatus as claimed in claim 9, characterized in that, The standard value for the power change rate of the DC microgrid system is as follows: In the above formula, This represents the standard value for the power change rate of a DC microgrid system. This represents the total load power at the current moment. for Total load power before time, To rewind time, This is the normalization coefficient.

11. The apparatus as claimed in claim 10, characterized in that, The backtracking time is 0.1 seconds.

12. The apparatus as claimed in claim 9, characterized in that, The power variation factor of the DC microgrid system is as follows: In the above formula, This represents the standard value for the power change rate of a DC microgrid system. The power variation factor of a DC microgrid system. This is a preset limit value.

13. The apparatus as claimed in claim 12, characterized in that, The preset limit value is 0.

1.

14. The apparatus as claimed in claim 12, characterized in that, The supercapacitor power allocation coefficient is as follows: In the above formula, This refers to the power distribution factor of the supercapacitor. This refers to the current moment.

15. The apparatus as claimed in claim 14, characterized in that, The reference output power of the supercapacitor is as follows: In the above formula, This is the reference output power of the supercapacitor. This represents the total output power of the energy storage system.

16. The apparatus as claimed in claim 15, characterized in that, The reference output power of the battery is as follows: In the above formula, This is the reference output power of the battery.

17. A computer device, characterized in that, include: One or more processors; The processor is used to execute one or more programs; When the one or more programs are executed by the one or more processors, the hybrid energy storage power allocation method for dynamic adjustment as described in any one of claims 1 to 8 is implemented.

18. A computer-readable storage medium, characterized in that, It contains a computer program, which, when executed, implements the hybrid energy storage power allocation method for dynamic adjustment as described in any one of claims 1 to 8.

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