A method and system for energy management of a hybrid power system supporting dual mode operation

Abstract

The embodiment of the application provides a kind of photovoltaic energy storage power generation system energy management method and system supporting dual-mode operation, by judging local load level in photovoltaic energy storage power generation system, energy storage system can be selected to work in local generation and use self-balancing mode and feed network photovoltaic power fluctuation suppression mode, in local generation and use self-balancing mode, energy storage system can compensate the difference power after photovoltaic power generation and local load action based on its energy storage and transfer capacity, so that local load does not need to absorb energy from power grid;In feed network photovoltaic power fluctuation suppression mode, energy storage system can suppress high-frequency fluctuation component in photovoltaic output power, limit the climbing rate.

Description

Technical Field

[0001] This invention relates to the field of energy management technology for power generation systems, and more particularly to an energy management method and system for a photovoltaic-storage power generation system that supports dual-mode operation. Background Technology

[0002] The development and utilization of renewable energy plays a crucial role in addressing the energy crisis and environmental problems. Given the obvious advantages of solar energy, such as its easy availability, massive quantity, and harmlessness, photovoltaic power generation has become one of the main ways to utilize renewable energy.

[0003] Due to seasonal and climatic factors, photovoltaic power generation exhibits significant fluctuations and uncertainties. As its scale expands, its integration into the power grid can impact the grid's operation, affecting its safe and stable function. Energy storage, capable of storing or releasing a certain amount of electrical energy, can store some energy during peak photovoltaic power generation periods and release it during peak periods, thus achieving peak shaving and valley filling. Considering the relatively high economic cost of energy storage, a single peak shaving and valley filling operation mode cannot fully realize the value of energy storage; therefore, seeking multi-mode reuse of energy storage systems is of significant practical importance. Summary of the Invention

[0004] This invention provides an energy management method and system for a photovoltaic-storage power generation system that supports dual-mode operation, in order to solve the problem that a single peak-shaving and valley-filling operation mode cannot fully realize the value of energy storage, nor can it improve the utilization efficiency of energy storage and the overall economy.

[0005] In a first aspect, embodiments of the present invention provide an energy management method for a photovoltaic-storage power generation system supporting dual-mode operation, wherein the photovoltaic-storage power generation system includes a photovoltaic power source, an energy storage system, and a local load, and the method includes:

[0006] Step S1: Obtain the power of the photovoltaic power source, the energy storage system, and the local load;

[0007] Step S2: If it is determined that the power of the local load exceeds a preset threshold, the energy storage system is controlled to enter the local power generation and consumption self-balancing mode, and the power difference between the local load and the photovoltaic power source is used as the power reference value of the energy storage system; if it is determined that the power of the local load does not exceed the preset threshold, the energy storage system is controlled to enter the grid-feed photovoltaic power fluctuation smoothing mode, and the fluctuation component in the power of the photovoltaic power source is determined based on the moving average filtering algorithm, and the fluctuation component is used as the power reference value of the energy storage system.

[0008] Step S3: Using the power reference value as the set value and the measured energy storage output power as the feedback value, determine the reference current based on the PID controller, and determine the modulation voltage of the three-phase inverter of the energy storage system based on the reference current.

[0009] Preferably, the photovoltaic power source is a single-stage photovoltaic power source, which operates in maximum power point tracking (MPPT) mode.

[0010] Preferably, step S1 specifically includes:

[0011] The output voltage and output current information of the photovoltaic power source, the energy storage system, and the local load are collected to determine the output power of the photovoltaic power source, the energy storage system, and the local load, and to determine the power difference between the local load and the photovoltaic power source.

[0012] Preferably, in step S2, the fluctuation component in the power of the photovoltaic power source is:

[0013]

[0014] In the above formula, Let P be the fluctuation component of the photovoltaic power output at time k. PV (k) represents the output power of the photovoltaic power source measured at time k, and N is the number of sampled data within the sliding window, n∈[1,N].

[0015] Preferably, in step S2, when the energy storage system enters the local generation and consumption self-balancing mode, if the SOC of the energy storage system is greater than the SOC of the energy storage system... max or less than SOC min If the energy storage system is in an overcharge or over-discharge state, the power reference value of the energy storage system is set to 0.

[0016] Preferably, in step S2, when the energy storage system enters the grid-feed photovoltaic power fluctuation smoothing mode, if the SOC of the energy storage system is greater than the SOC of the grid-feed photovoltaic power fluctuation smoothing mode... max or less than SOC min If the energy storage system is in an overcharge or over-discharge state, the power reference value of the energy storage system is set to 0.

[0017] Preferably, the SOC of the energy storage system is:

[0018]

[0019] In the above formula, SoC(k) is the SOC of the energy storage system at time k, and E batt For energy storage capacity, P batt This refers to the output power of the energy storage system.

[0020] Secondly, embodiments of the present invention provide an energy management system for a photovoltaic-storage power generation system that supports dual-mode operation, comprising:

[0021] The acquisition module obtains the power of the photovoltaic power source, the energy storage system, and the local load;

[0022] The mode adjustment module, if it determines that the power of the local load exceeds a preset threshold, controls the energy storage system to enter a local power generation and consumption self-balancing mode, using the power difference between the local load and the photovoltaic power source as the power reference value of the energy storage system; if it determines that the power of the local load does not exceed a preset threshold, it controls the energy storage system to enter a grid-feed photovoltaic power fluctuation smoothing mode, determining the fluctuation component in the power of the photovoltaic power source based on a moving average filtering algorithm, and using the fluctuation component as the power reference value of the energy storage system.

[0023] The energy storage management module uses the power reference value as the set value and the measured energy storage output power as the feedback value. It determines the reference current based on the PID controller and determines the modulation voltage of the three-phase inverter of the energy storage system based on the reference current.

[0024] Thirdly, embodiments of the present invention provide an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the program, it implements the steps of the energy management method for a photovoltaic-storage power generation system supporting dual-mode operation as described in the first aspect of the present invention.

[0025] Fourthly, embodiments of the present invention provide a non-transitory computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of the energy management method for a photovoltaic-storage power generation system supporting dual-mode operation as described in the first aspect of the present invention.

[0026] This invention provides an energy management method and system for a photovoltaic-storage power generation system that supports dual-mode operation. By determining the local load level in the photovoltaic-storage power generation system, the energy storage system can choose to operate in a local self-balancing mode and a grid-feed photovoltaic power fluctuation smoothing mode. In the local self-balancing mode, the energy storage system can compensate for the power difference between photovoltaic power generation and local load based on its energy storage and transfer capabilities, so that the local load does not need to absorb energy from the grid. In the grid-feed photovoltaic power fluctuation smoothing mode, the energy storage system can smooth out the high-frequency fluctuation components in the photovoltaic output power and limit the ramp rate. Attached Figure Description

[0027] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0028] Figure 1 This is a topology diagram of a photovoltaic-storage power generation system according to an embodiment of the present invention;

[0029] Figure 2 This is a flowchart of an energy management method for a photovoltaic-storage power generation system supporting dual-mode operation according to an embodiment of the present invention;

[0030] Figure 3 This is a local load curve according to an embodiment of the present invention;

[0031] Figure 4 This is a comparison chart of photovoltaic output active power and grid-connected active power according to an embodiment of the present invention;

[0032] Figure 5 To output active power for energy storage according to an embodiment of the present invention;

[0033] Figure 6 This is a schematic diagram of the physical structure according to an embodiment of the present invention. Detailed Implementation

[0034] 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.

[0035] In the embodiments of this application, the term "and / or" is merely a description of the relationship between related objects, indicating that there can be three relationships. For example, A and / or B can represent three situations: A exists alone, A and B exist simultaneously, and B exists alone.

[0036] The terms "first" and "second" used in the embodiments of this application are for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion. For example, a system, product, or device that includes a series of components or units is not limited to the listed components or units, but may optionally include unlisted components or units, or may optionally include other components or units inherent to such products or devices. In the description of this application, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0037] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0038] Photovoltaic power generation exhibits significant volatility and uncertainty. As its scale expands, its integration into the power grid can impact the grid's stability and security. Energy storage, capable of storing or releasing a certain amount of electrical energy, can store some energy during peak photovoltaic power generation periods and release it during peak periods, thus achieving peak shaving and valley filling. However, considering the relatively high economic cost of energy storage, a single peak shaving and valley filling operation mode cannot fully realize the value of energy storage, nor can it improve the utilization efficiency and overall economic viability.

[0039] Therefore, this invention provides an energy management method for a photovoltaic-storage power generation system that supports dual-mode operation. By determining the local load level in the photovoltaic-storage power generation system, the energy storage system can choose to operate in a local self-balancing mode and a grid-feed photovoltaic power fluctuation smoothing mode. In the local self-balancing mode, the energy storage system, based on its energy storage and transfer capabilities, can compensate for the power difference between photovoltaic power generation and local load, so that the local load does not need to absorb energy from the grid. In the grid-feed photovoltaic power fluctuation smoothing mode, the energy storage system can smooth out high-frequency fluctuation components in the photovoltaic output power and limit the ramp rate. The following will elaborate and describe this method through several embodiments.

[0040] Figure 1 and Figure 2An energy management method for a photovoltaic-storage power generation system supporting dual-mode operation is provided in this embodiment of the invention. The photovoltaic-storage power generation system includes a photovoltaic power source, an energy storage system, a local load, and a public power grid. The method includes:

[0041] Step S1: Obtain the power of the photovoltaic power source, the energy storage system, and the local load;

[0042] In this embodiment, the photovoltaic power source includes a photovoltaic array, and the energy storage system includes a battery, a three-phase inverter (DC / AC inverter), and an energy management system. By collecting the output voltage and current information of the photovoltaic power source, the energy storage system, and the local load, the output power of the photovoltaic power source, the energy storage system, and the local load is determined, and the power difference between the local load and the photovoltaic power source is determined. The photovoltaic power source is a single-stage photovoltaic power source, and the single-stage photovoltaic power source operates in MPPT (Maximum Power Point Tracking) mode.

[0043] The measured output voltage and current information of the photovoltaic power source, energy storage system, and local load can be transmitted to the energy management system of the photovoltaic-energy storage system via a low-bandwidth communication network, and the active power difference can be calculated in the energy management system.

[0044] Step S2: If it is determined that the power of the local load exceeds a preset threshold P L_lim If the power difference between the local load and the photovoltaic power source is not exceeded, the energy storage system will enter a local self-balancing mode. The power reference value for the energy storage system will be the difference between the power of the local load and the photovoltaic output information. L_lim Then, the energy storage system is controlled to enter the grid photovoltaic power fluctuation smoothing mode, and the fluctuation component in the power of the photovoltaic power source is determined based on the moving average filtering algorithm, so as to use the fluctuation component as the power reference value of the energy storage system.

[0045] The fluctuation component in the power of the photovoltaic power source is:

[0046]

[0047] In the above formula, Let P be the fluctuation component of the photovoltaic power output at time k. PV (k) represents the output power of the photovoltaic power source measured at time k, and N is the number of sampled data within the sliding window, n∈[1,N].

[0048] When the energy storage system enters the local generation and consumption self-balancing mode, if the SOC of the energy storage system is greater than the SOC of the energy storage system...max or less than SOC min If the energy storage system is in an overcharge or over-discharge state, the power reference value of the energy storage system is set to 0.

[0049] When the energy storage system enters the grid-feed photovoltaic power fluctuation smoothing mode, if the SOC of the energy storage system is greater than the SOC of the grid-feed photovoltaic power fluctuation smoothing mode... max or less than SOC min If the energy storage system is in an overcharge or over-discharge state, the power reference value of the energy storage system is set to 0.

[0050] Wherein, the energy storage SOC of the energy storage system is:

[0051]

[0052] In the above formula, SoC(k) is the SOC of the energy storage system at time k, and E batt For energy storage capacity, P batt This refers to the output power of the energy storage system.

[0053] Step S3: Using the power reference value as the setpoint and the measured energy storage output power as the feedback value, determine the reference current (I) based on the PID controller. dref I qref , where are the given values ​​for the d-axis and q-axis of the inner current loop, respectively, and the modulation voltage of the three-phase inverter of the energy storage system is determined based on the reference current.

[0054] Figure 3 This is a curve showing the change in local load over 10 minutes. Figure 4 This refers to the active power output of photovoltaic power sources and the grid-connected active power of photovoltaic-storage combined power generation systems. Figure 5 It outputs active power for energy storage. Combined with... Figure 3 , 4 As shown in section 5, within 0 to 100 seconds, the local load is lower than the threshold P. L_lim At this time, the energy storage system operates in "grid-feed photovoltaic power fluctuation smoothing mode," compensating for the high-frequency components in the fluctuating output power of the photovoltaic power source, reducing the photovoltaic power generation ramp-up rate, and allowing a portion of the photovoltaic output to meet the consumption of local loads. The remaining power can be injected into the distribution network after being smoothed by energy storage, thereby effectively improving the impact of photovoltaic output uncertainty on the distribution network. Between 100s and 400s, as the local load increases, the threshold P... L_lim Above, the energy storage system switches to "local power generation and consumption self-balancing mode." At this time, the active power injected into the grid is balanced to 0 by the energy storage, and the active power difference between the photovoltaic system and the local load is entirely absorbed or provided by the energy storage. This operating mode can achieve local self-consumption under high load conditions. Between 400s and 600s, the local load drops back to the threshold P. L_limAt this point, the energy storage system autonomously switches back to the "grid-feed photovoltaic power fluctuation smoothing mode". As can be seen from the results of the embodiment, the energy management method for a photovoltaic-storage power generation system supporting dual-mode operation provided by this invention can adaptively switch operating modes according to local load levels. Through the coordinated operation of photovoltaic and energy storage, it improves the impact of photovoltaic power fluctuations on the distribution network, enhances the utilization efficiency of energy storage, and increases the economic efficiency of electricity consumption.

[0055] This invention also provides an energy management system for a photovoltaic-storage power generation system that supports dual-mode operation. Based on the energy management method for a photovoltaic-storage power generation system supporting dual-mode operation described in the above embodiments, the method includes:

[0056] The acquisition module obtains the power of the photovoltaic power source, the energy storage system, and the local load;

[0057] The mode adjustment module, if it determines that the power of the local load exceeds a preset threshold, controls the energy storage system to enter a local power generation and consumption self-balancing mode, using the power difference between the local load and the photovoltaic power source as the power reference value of the energy storage system; if it determines that the power of the local load does not exceed a preset threshold, it controls the energy storage system to enter a grid-feed photovoltaic power fluctuation smoothing mode, determining the fluctuation component in the power of the photovoltaic power source based on a moving average filtering algorithm, and using the fluctuation component as the power reference value of the energy storage system.

[0058] The energy storage management module uses the power reference value as the set value and the measured energy storage output power as the feedback value. It determines the reference current based on the PID controller and determines the modulation voltage of the three-phase inverter of the energy storage system based on the reference current.

[0059] Based on the same concept, this invention also provides a schematic diagram of a physical structure, such as... Figure 6 As shown, the server may include a processor 810, a communications interface 820, a memory 830, and a communication bus 840. The processor 810, communications interface 820, and memory 830 communicate with each other via the communication bus 840. The processor 810 can call logical instructions in the memory 830 to execute the steps of the energy management method for a photovoltaic-storage power generation system supporting dual-mode operation as described in the above embodiments. For example, this includes:

[0060] Step S1: Obtain the power of the photovoltaic power source, the energy storage system, and the local load;

[0061] Step S2: If it is determined that the power of the local load exceeds a preset threshold, the energy storage system is controlled to enter the local power generation and consumption self-balancing mode, and the power difference between the local load and the photovoltaic power source is used as the power reference value of the energy storage system; if it is determined that the power of the local load does not exceed the preset threshold, the energy storage system is controlled to enter the grid-feed photovoltaic power fluctuation smoothing mode, and the fluctuation component in the power of the photovoltaic power source is determined based on the moving average filtering algorithm, and the fluctuation component is used as the power reference value of the energy storage system.

[0062] Step S3: Using the power reference value as the set value and the measured energy storage output power as the feedback value, determine the reference current based on the PID controller, and determine the modulation voltage of the three-phase inverter of the energy storage system based on the reference current.

[0063] Furthermore, the logical instructions in the aforementioned memory 830 can be implemented as software functional units and, when sold or used as independent products, can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, essentially, or the part that contributes to the prior art, or a part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0064] Based on the same concept, embodiments of the present invention also provide a non-transitory computer-readable storage medium storing a computer program containing at least one piece of code executable by a master control device to control the master control device to implement the steps of the energy management method for a photovoltaic-storage power generation system supporting dual-mode operation as described in the above embodiments. For example, it includes:

[0065] Step S1: Obtain the power of the photovoltaic power source, the energy storage system, and the local load;

[0066] Step S2: If it is determined that the power of the local load exceeds a preset threshold, the energy storage system is controlled to enter the local power generation and consumption self-balancing mode, and the power difference between the local load and the photovoltaic power source is used as the power reference value of the energy storage system; if it is determined that the power of the local load does not exceed the preset threshold, the energy storage system is controlled to enter the grid-feed photovoltaic power fluctuation smoothing mode, and the fluctuation component in the power of the photovoltaic power source is determined based on the moving average filtering algorithm, and the fluctuation component is used as the power reference value of the energy storage system.

[0067] Step S3: Using the power reference value as the set value and the measured energy storage output power as the feedback value, determine the reference current based on the PID controller, and determine the modulation voltage of the three-phase inverter of the energy storage system based on the reference current.

[0068] Based on the same technical concept, this application also provides a computer program, which, when executed by a main control device, is used to implement the above-described method embodiments.

[0069] The program may be stored, in whole or in part, on a storage medium packaged with the processor, or in part or in whole on a memory not packaged with the processor.

[0070] Based on the same technical concept, embodiments of this application also provide a processor for implementing the above-described method embodiments. The processor may be a chip.

[0071] In summary, the energy management method and system for a photovoltaic-storage power generation system supporting dual-mode operation provided by the embodiments of the present invention can select to operate in a local self-balancing mode and a grid-feed photovoltaic power fluctuation smoothing mode by judging the local load level in the photovoltaic-storage power generation system. In the local self-balancing mode, the energy storage system can compensate for the power difference after the interaction between photovoltaic power generation and local load based on its energy storage and transfer capabilities, so that the local load does not need to absorb energy from the grid. In the grid-feed photovoltaic power fluctuation smoothing mode, the energy storage system can smooth the high-frequency fluctuation components in the photovoltaic output power and limit the ramp rate.

[0072] The various embodiments of the present invention can be combined arbitrarily to achieve different technical effects.

[0073] In the above embodiments, implementation can be achieved, in whole or in part, through software, hardware, firmware, or any combination thereof. When implemented in software, it can be implemented, in whole or in part, as a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, all or part of the processes or functions described in this application are generated. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions can be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another. For example, the computer instructions can be transmitted from one website, computer, server, or data center to another website, computer, server, or data center via wired (e.g., coaxial cable, fiber optic, digital subscriber line) or wireless (e.g., infrared, wireless, microwave, etc.) means. The computer-readable storage medium can be any available medium accessible to a computer or a data storage device such as a server or data center that integrates one or more available media. The available medium can be a magnetic medium (e.g., floppy disk, hard disk, magnetic tape), an optical medium (e.g., DVD), or a semiconductor medium (e.g., solid-state drive).

[0074] Those skilled in the art will understand that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. This program can be stored in a computer-readable storage medium, and when executed, it can include the processes described in the above method embodiments. The aforementioned storage medium includes various media capable of storing program code, such as ROM or random access memory (RAM), magnetic disks, or optical disks.

[0075] 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 them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. An energy management method for a photovoltaic-storage power generation system supporting dual-mode operation, wherein the photovoltaic-storage power generation system includes a photovoltaic power source, an energy storage system, and a local load, characterized in that, The method includes: Step S1: Obtain the power of the photovoltaic power source, the energy storage system, and the local load; Step S2: If it is determined that the power of the local load exceeds a preset threshold, the energy storage system is controlled to enter the local power generation and consumption self-balancing mode, and the power difference between the local load and the photovoltaic power source is used as the power reference value of the energy storage system; if it is determined that the power of the local load does not exceed the preset threshold, the energy storage system is controlled to enter the grid-feed photovoltaic power fluctuation smoothing mode, and the fluctuation component in the output power of the photovoltaic power source is determined based on the moving average filtering algorithm, and the fluctuation component is used as the power reference value of the energy storage system. Step S3: Using the power reference value as the set value and the measured energy storage output power as the feedback value, determine the reference current based on the PID controller, and determine the modulation voltage of the three-phase inverter of the energy storage system based on the reference current.

2. The energy management method for a photovoltaic-storage power generation system supporting dual-mode operation according to claim 1, characterized in that, The photovoltaic power supply is a single-stage photovoltaic power supply, which operates in maximum power point tracking (MPPT) mode.

3. The energy management method for a photovoltaic-storage power generation system supporting dual-mode operation according to claim 1, characterized in that, Step S1 specifically includes: The output voltage and output current information of the photovoltaic power source, the energy storage system, and the local load are collected to determine the output power of the photovoltaic power source, the energy storage system, and the local load, and to determine the power difference between the local load and the photovoltaic power source.

4. The energy management method for a photovoltaic-storage power generation system supporting dual-mode operation according to claim 1, characterized in that, In step S2, the fluctuation component in the output power of the photovoltaic power source is: In the above formula, Let P be the fluctuation component of the photovoltaic power output at time k. PV (k) represents the output power of the photovoltaic power source measured at time k, and N is the number of sampled data within the sliding window, n∈[1,N].

5. The energy management method for a photovoltaic-storage power generation system supporting dual-mode operation according to claim 1, characterized in that, In step S2, when the energy storage system enters the local generation and consumption self-balancing mode, if the SOC of the energy storage system is greater than the SOC of the energy storage system... max or less than SOC min If the energy storage system is found to be in an overcharged or over-discharged state, the power reference value of the energy storage system is set to 0.

6. The energy management method for a photovoltaic-storage power generation system supporting dual-mode operation according to claim 1, characterized in that, In step S2, when the energy storage system enters the grid-feed photovoltaic power fluctuation smoothing mode, if the SOC of the energy storage system is greater than the SOC of the grid-feed photovoltaic power fluctuation smoothing mode... max or less than SOC min If the energy storage system is found to be in an overcharged or over-discharged state, the power reference value of the energy storage system is set to 0.

7. The energy management method for a photovoltaic-storage power generation system supporting dual-mode operation according to claim 5 or 6, characterized in that, The method for measuring the State of Charge (SOC) of the energy storage system is as follows: In the above formula, SoC(k) is the SOC of the energy storage system at time k, and E batt For energy storage capacity, P batt This refers to the output power of the energy storage system.

8. An energy management system for a photovoltaic-storage power generation system supporting dual-mode operation, characterized in that, include: The data acquisition module obtains the power from photovoltaic power sources, energy storage systems, and local loads. If the mode adjustment module determines that the power of the local load exceeds a preset threshold, it controls the energy storage system to enter a local power generation and consumption self-balancing mode, using the power difference between the local load and the photovoltaic power source as the power reference value of the energy storage system. If it is determined that the power of the local load does not exceed a preset threshold, the energy storage system is controlled to enter the grid-feed photovoltaic power fluctuation smoothing mode. The fluctuation component in the power of the photovoltaic power source is determined based on the moving average filtering algorithm, and the fluctuation component is used as the power reference value of the energy storage system. The energy storage management module uses the power reference value as the set value and the measured energy storage output power as the feedback value. It determines the reference current based on the PID controller and determines the modulation voltage of the three-phase inverter of the energy storage system based on the reference current.

9. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the program, it implements the steps of the energy management method for a photovoltaic-storage power generation system supporting dual-mode operation as described in any one of claims 1 to 7.

10. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that, When executed by a processor, the computer program implements the steps of the energy management method for a photovoltaic-storage power generation system supporting dual-mode operation as described in any one of claims 1 to 7.

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