WO2024113110A1

WO2024113110A1 - Electric power management method, and energy storage device and storage medium

Info

Publication number: WO2024113110A1
Application number: PCT/CN2022/134774
Authority: WO
Inventors: 梁志刚; 张宏韬; 张凯; 陈熙; 王雷
Original assignee: 深圳市正浩创新科技股份有限公司
Priority date: 2022-11-28
Filing date: 2022-11-28
Publication date: 2024-06-06
Also published as: CN116210020A8; CN116210020A

Abstract

An electric power management method, wherein the method is applied to an energy storage device. The method comprises: after an energy storage device is connected to a household power grid system, injecting a test electrical signal into the household power grid system by means of the energy storage device; acquiring a response electrical signal, which is fed back by the household power grid system, wherein the response electrical signal corresponds to the test electrical signal; and calculating an electric power of a target electric load in the household power grid system on the basis of the test electrical signal and the response electrical signal.

Description

Electric power management method, energy storage device and storage medium

Technical Field

The present application relates to the field of energy management technology, and in particular to an electric power management method, an energy storage device and a storage medium.

Background technique

The statements herein merely provide background information related to the present application and do not necessarily constitute exemplary techniques.

With the development of science and technology, the power supply in the home is becoming more and more diversified. For example, the home may include one or more power supply sources such as a mains interface, solar energy equipment, and energy storage power supply.

When there are multiple power supplies in a home, the power distribution equipment or part of the power supplies needs to obtain the power consumption of the home to allocate the output of each power supply. In related solutions, it is usually necessary to change the distribution lines in the home and connect corresponding detection devices to the distribution lines in the home to monitor the power consumption of the home, which consumes a lot of manpower and material resources.

Summary of the invention

According to various embodiments of the present application, a method for managing electric power, an energy storage device, and a storage medium are provided.

In a first aspect, the present application provides a method for managing electric power, the method being applied to an energy storage device, the method comprising:

After the energy storage device is connected to the home power grid system, injecting a test electrical signal into the home power grid system through the energy storage device;

Acquire a response electrical signal fed back by the home power grid system, wherein the response electrical signal corresponds to the test electrical signal;

Based on the test electrical signal and the response electrical signal, the electrical power of a target electrical load in the home power grid system is calculated, and the target electrical load includes a resistive electrical load and/or a capacitive electrical load.

In a second aspect, the present application also provides an energy storage device, including:

A memory and a processor; wherein the memory is connected to the processor, and the memory is used to store programs; the processor is used to implement the steps of the electric power management method as described in any one of the embodiments of the present application by running the programs stored in the memory.

In a third aspect, the present application further provides a computer-readable storage medium, which stores a computer program. When the computer program is executed by a processor, the processor implements the steps of the electric power management method as described in any one of the embodiments of the present application.

The details of one or more embodiments of the present application are set forth in the following drawings and description. Other features, objects, and advantages of the present application will become apparent from the description, drawings, and claims.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

FIG1 is a schematic diagram of the steps of a method for managing electric power provided in an embodiment of the present application.

FIG. 2 is a circuit diagram of a method for managing electric power provided in an embodiment of the present application.

FIG3 is a schematic diagram of the steps of another method for managing electric power provided in an embodiment of the present application.

FIG4 is a schematic block diagram of an electric power management device provided in an embodiment of the present application.

FIG5 is a schematic diagram of an energy storage device provided in an embodiment of the present application.

It should be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present application.

Detailed ways

The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

The flowcharts shown in the accompanying drawings are only examples and do not necessarily include all the contents and operations/steps, nor must they be executed in the order described. For example, some operations/steps may also be decomposed, combined or partially merged, so the actual execution order may change according to actual conditions.

It should be understood that the terms used in this application specification are only for the purpose of describing specific embodiments and are not intended to limit the application. As used in this application specification and the appended claims, the singular forms "a", "an" and "the" are intended to include plural forms unless the context clearly indicates otherwise.

It should also be understood that the term “and/or” used in the specification and appended claims refers to and includes any and all possible combinations of one or more of the associated listed items.

To facilitate understanding of the embodiments of the present application, some background information involved in the embodiments of the present application is briefly described below.

At present, the power supply in the home is showing a trend of diversification. The home may include one or more power supplies such as the mains interface, solar energy equipment, energy storage power supply, etc. When there are multiple power supplies in the home, for example, when the home has a power grid, energy storage equipment and photovoltaic equipment to supply power to the home load at the same time, it is necessary to obtain the power consumption of the home in order to allocate the output of each power supply to meet the power demand of the home.

In related schemes, when obtaining the household's electricity consumption, it is usually necessary to change the distribution lines in the home, and connect corresponding detection devices in series to the household's distribution lines to monitor the household's electricity consumption, which requires a lot of manpower and material resources.

Therefore, the present application proposes a method for managing electric power consumption, which can realize the management of electric power consumption of a household power grid system without modifying the household power distribution lines, thereby saving manpower, material resources and other resources.

In conjunction with the accompanying drawings, some embodiments of the present application are described in detail below. In the absence of conflict, the following embodiments and features in the embodiments can be combined with each other.

Please refer to Figures 1 and 2. Figure 1 is a schematic diagram of the steps of a method for managing electric power provided in an embodiment of the present application; Figure 2 is a circuit equivalent diagram of a method for managing electric power provided in an embodiment of the present application. The method proposed in the present application can be applied to energy storage devices to achieve electric power management.

As shown in FIG. 1 , the electric power management method includes steps S110 to S130 .

S110: After the energy storage device is connected to the home power grid system, a test electrical signal is injected into the home power grid system through the energy storage device.

In order to achieve power management, the energy storage device can be first connected to the home power grid system through a socket or other means to inject a test electrical signal into the home power grid system, so that the power management of the home power grid system can be achieved based on the test electrical signal.

It should be noted that the embodiment of the present application does not limit the number of groups of injected test electrical signals. For example, one group can be injected at a time, or multiple groups can be injected at a time. The present application will be described later using the example of an energy storage device injecting multiple groups of test electrical signals into a home power grid at one time.

Furthermore, the embodiment of the present application does not limit the frequency of the test electrical signal. For example, the frequency range of the test signal can be within the range of 0 to 100 kHz.

S120: Acquire a response electrical signal fed back by the home power grid system, where the response electrical signal corresponds to the test electrical signal.

After obtaining the response electrical signal fed back by the home power grid system, the energy storage device can obtain the corresponding response electrical signal fed back by the home power grid system through measurement or other methods based on the injected test electrical signal. In this way, the energy storage device can calculate the power consumption of the target power load in the home power grid system based on the test electrical signal and the response electrical signal.

It should be noted that in order to avoid the influence of the inherent frequency of the electrical signal of the power grid itself, the frequency of the test electrical signal injected by the energy storage device should be inconsistent with the mains frequency. In one embodiment, the frequency of the test electrical signal can also be set to not be an integer multiple of the mains frequency. In this way, the energy storage device can better separate the test electrical signal from the response electrical signal, so as to more accurately obtain the response electrical signal fed back by the home power grid system. For example, if the mains frequency in the home power grid system is 60HZ, the frequency of the test electrical signal injected by the energy storage device can be 80HZ. It should be noted that the frequencies in the above embodiments are only used for illustration and are not used to limit the scope of protection of this application. Those skilled in the art can reasonably set them according to their needs.

S130: Calculate the power consumption of the target power load in the home power grid system based on the test electrical signal and the response electrical signal, wherein the target power load includes a resistive power load and/or a capacitive power load.

After the energy storage device obtains the test electrical signal and the response electrical signal, the electrical power consumption of the target electrical load in the home power grid system can be calculated based on the test electrical signal and the response electrical signal.

Optionally, the above-mentioned calculation of the power consumption of the home power grid system based on the test electrical signal and the response electrical signal includes: calculating the equivalent resistance of the target power load in the home power grid system according to the test electrical signal and the response electrical signal; and determining the power consumption of the target power load in the home power grid system based on the equivalent resistance and the supply voltage of the home power grid system.

As shown in FIG2 , the household power grid system includes at least a power grid and a household load. The power grid refers to the power supply network that supplies power to the load when the energy storage device is connected to the household power grid through a socket. Usually, the power grid is the mains. Among them, the household load is a resistive power load and/or a capacitive power load, which can be equivalent to a resistor in the circuit. In addition, the power grid can be equivalent to an ideal voltage source Vg connected in series with an inductor L.

The target power consumption of the home power grid system can be obtained based on the equivalent resistance and the power supply voltage of the home power grid system through the following formula:

Among them, P is the power consumption of the household power grid system; R is the equivalent resistance; U is the effective voltage value of the household power grid system.

The effective voltage value in the home power grid system can be the standard mains voltage value of 220V, or can be obtained by calculating the port voltage. Specifically, after the energy storage device is connected to the home power grid through a port (such as a socket), the voltage value of the port can be collected, and the voltage value of the port can be calculated to obtain the effective voltage value in the home power grid.

The equivalent resistance can be calculated based on the current of the test electrical signal and the voltage of the response electrical signal. In this way, the power consumption of the target electrical load in the home power grid system can be determined based on the equivalent resistance and the effective voltage value of the home power grid system.

Optionally, in order to obtain the equivalent resistance of the target power load in the home power grid system, the port resistance value and the port reactance value of the energy storage device connected to the home power grid can be calculated based on the test electrical signal and the response electrical signal; the equivalent resistance of the target power load in the home power grid system is calculated based on the test electrical signal, the port resistance value and the port reactance value.

It is understandable that the energy storage device is connected to the home power grid through a port (such as a socket). When the energy storage device injects a test electrical signal into the home power grid system through the port, for the energy storage device, the home load and the power grid can be regarded as equivalent loads of the energy storage device, and the energy storage device can obtain the impedance of the equivalent load through the test electrical signal and the response electrical signal, that is, the above-mentioned port resistance value and port reactance value.

Specifically, the port resistance and port reactance can be calculated using the following formula:

Wherein, V is the voltage value of the response electrical signal; i is the current value of the test electrical signal; Rest _is the port resistance value; and Zest _is the port reactance value.

After the energy storage device is connected to the home power grid system, multiple groups of test electrical signals with different current values can be injected into the home power grid, and multiple groups of response electrical signals with corresponding voltage values can be obtained based on the multiple groups of test electrical signals with different current values. Therefore, when the voltage value of the response electrical signal and the current value of the test electrical signal are known, the port resistance value and the port reactance value can be calculated by the above formula.

Furthermore, the household load and the power grid in FIG. 2 are equivalent to being connected in parallel, so the following derivation formula can be obtained:

Among them, R is the equivalent resistance; L is the equivalent inductance of the household power grid system; ω is the angular frequency of the test electrical signal.

In this way, the formula for calculating the equivalent resistance of the target power load of the home power grid system can be derived based on the above two formulas (2) and (3):

Wherein, R is the equivalent resistance; ω is the angular frequency of the test electrical signal; and L is the equivalent inductance of the household power grid system.

It should be noted that the angular frequency of the test electrical signal is 2π times the frequency of the test electrical signal.

Therefore, when the port resistance value and the port reactance value are calculated and the angular frequency of the test electrical signal is known, the equivalent resistance of the power load of the home power grid system can be calculated by the above formula. In this way, the target power consumption of the home power grid system can be calculated based on the relationship formula between the equivalent resistance of the target power load of the home power grid system, the supply voltage of the home power grid system and the power consumption of the home power grid system.

Optionally, when the energy storage device injects multiple groups of test electrical signals into the home power grid at one time, the least squares method can be used to improve the calculation accuracy of the above-mentioned port resistance value and port reactance value, thereby improving the accuracy of power calculation of the target power load in the home power grid system.

It should be noted that the least square method (also known as the least square method) is a mathematical optimization technique. It finds the best function matching of data by minimizing the sum of squares of errors, so that users can use the least square method to easily obtain unknown data and minimize the sum of squares of errors between the obtained data and the actual data. In addition, the least square method can also be used for curve fitting. Some other optimization problems can also be expressed by the least square method by minimizing energy or maximizing entropy.

Specifically, the corresponding response electrical signal can be obtained based on each group of test electrical signals, and the corresponding equivalent resistance R can be calculated. Then, after the energy storage device injects n groups of test electrical signals into the home power grid, n groups of equivalent resistances R1, R2...Rn are obtained, and the best function matching is fitted according to the least squares method and multiple groups of equivalent resistances R1, R2...Rn, and the equivalent resistance data with large errors caused by sampling errors are eliminated according to the best function, so that the obtained equivalent resistance data is the most accurate. Finally, the power consumption of the target power load in the corresponding home power grid system is calculated according to the obtained equivalent resistance R and the above formula (1). In this way, after obtaining the power consumption of multiple groups of home power grid systems, the above data can be optimized by linear regression equations or curve fitting, so as to obtain more accurate power consumption data of the target power load in the home power grid system.

Of course, in some other embodiments, after the energy storage device injects n groups of test electrical signals into the home power grid and obtains n groups of equivalent resistances R1, R2...Rn, it is also possible to obtain n groups of power consumption P1, P2...Pn according to the n groups of equivalent resistance data and the above formula (1). After that, the fitting function is obtained by the least squares method, and the power consumption data with large errors are eliminated according to the fitting function to obtain more accurate power consumption data of the target power load in the home power grid system.

In the embodiment of the present application, by using the energy storage device to inject the test electrical signal into the home power grid system and obtaining the corresponding response electrical signal fed back by the home power grid system, the power consumption management can be realized based on the test electrical signal and the response electrical signal. In addition, in order to improve the accuracy of the power consumption calculation of the target power load in the home power grid system, multiple groups of test electrical signals can be injected at one time, and the least square method can be used to indirectly improve the accuracy of the power consumption calculation of the target power load in the home power grid system.

Please refer to FIG. 3, which is a schematic diagram of the steps of another method for managing power consumption provided by an embodiment of the present application. As shown in FIG. 3, the method for managing power consumption proposed in the present application includes steps S210 to S230. Among them, the method is applied to an energy storage device, the energy storage device is connected to a photovoltaic device, and after calculating the household power consumption of the target power load in the household power grid system based on the test electrical signal and the response electrical signal, it also includes:

Step S210: Obtain the output power of the photovoltaic device.

Since a home may include one or more power sources such as a mains interface, solar equipment, and energy storage power supply, when a home has grid power supply, photovoltaic equipment, and energy storage equipment at the same time, it is necessary to adjust the output of each power supply based on the household power consumption calculated above.

It should be noted that the photovoltaic device can be connected to the energy storage device. Furthermore, the power generated by the photovoltaic device can be used to power the home through the bypass of the energy storage device, or the energy storage device can be charged through the power conversion circuit in the energy storage device. In addition, the photovoltaic device and the energy storage device can also be used to power the home together.

Step S220: When the output power of the photovoltaic device is greater than the power consumption of the target power load in the home power grid system, the photovoltaic device is controlled to independently supply power to the home power grid system.

Based on this, the output power of the photovoltaic device can be obtained, and based on the power consumption of the home grid system obtained above, it can be judged whether the output power of the photovoltaic device is greater than the power consumption of the target power load in the home grid system. When the output power of the photovoltaic device is greater than the power consumption of the target power load in the home grid system, the photovoltaic device is controlled to independently supply power to the home grid system.

In this case, neither the energy storage device nor the power grid needs to supply power to the home, and the energy storage device works in bypass mode. If the energy storage device needs to be charged, and the photovoltaic device still has excess power after meeting the household electricity consumption. The energy storage device can be charged to store excess electricity. Specifically, according to the difference between the power output of the current photovoltaic device and the power consumption of the target power load in the home power grid system, the excess power output of the photovoltaic device, that is, the difference, can be output to the energy storage device, so that the photovoltaic device can generate electricity at maximum power tracking, that is, the photovoltaic device can output the maximum power according to the current lighting conditions, without having to use the power consumption of the target power load in the current home power grid system as the target power to output the corresponding output power, so that the photovoltaic device can convert the light resources with the highest efficiency.

In some embodiments, when the output power of the photovoltaic device is equal to the power consumption of the target power load in the home power grid system, the photovoltaic device can be directly allowed to operate at the maximum power tracking point to output the maximum output power to supply the power consumption of the target power load in the home power grid system, without the need for energy storage equipment and the power grid to provide electricity.

Step S230: When the output power of the photovoltaic device is less than the power consumption of the target power load in the home power grid system, a power supply request instruction is generated according to the power difference between the output power and the power consumption; the power supply request instruction is used to request the energy storage device or the power grid to provide an electrical signal with a power difference.

After receiving the electrical signal with the power difference, the power grid will output a power supply electrical signal corresponding to the power difference to supply power to the household load.

In other embodiments, if the output power of the photovoltaic device is less than the power consumption of the target power load in the home power grid system, a power supply request instruction is generated based on the power difference between the output power and the power consumption; the power supply request instruction is used to request the energy storage device or the power grid to provide power with the power difference.

It is understandable that when the power generation of photovoltaic equipment cannot meet the household electricity demand, the power grid can be preferentially obtained from the power grid, that is, the power grid can be requested to provide an electrical signal with a power difference by generating a power request instruction.

Optionally, since energy storage devices are usually used as backup power, the grid can give priority to supplying power to the home. When the photovoltaic device cannot meet the power demand of the target power load in the home and is not connected to the grid, the energy storage device can be requested to supply power to the home to meet the home's power demand.

In an embodiment of the present application, when a home is simultaneously powered by a power grid, photovoltaic equipment, and energy storage equipment, the output of each power supply can be adjusted based on the power consumption of the home's target power load and the output power of the photovoltaic equipment calculated above to meet the home's electricity needs.

The power management method proposed in this application can use energy storage equipment to inject test electrical signals into the home power grid system, and obtain the corresponding response electrical signals fed back by the home power grid system, and then realize power management based on the test electrical signals and the response electrical signals. In addition, when there are grid power supply, photovoltaic equipment and energy storage equipment in the home at the same time, the output of each power supply can also be allocated based on the calculated target power load power in the home and the output power of the photovoltaic equipment, so as to meet the power demand of the home.

Please refer to FIG. 4 , which is a schematic block diagram of another electric power management device provided in an embodiment of the present application. The computing device may be configured in a server to execute the aforementioned electric power management method.

As shown in FIG. 4 , the electric power management device 200 includes: a signal injection module 210 , an acquisition module 220 , and a calculation module 230 .

The signal injection module 210 is used to inject a test electrical signal into the home power grid system through the energy storage device after the energy storage device is connected to the home power grid system.

The acquisition module 220 is used to acquire a response electrical signal fed back by the home power grid system, wherein the response electrical signal corresponds to the test electrical signal.

The calculation module 230 is used to calculate the household power consumption of the target power load in the household power grid system based on the test electrical signal and the response electrical signal, and the target power load includes a resistive power load and/or a capacitive power load.

It should be noted that those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working processes of the above-described devices and modules and units can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

The method and apparatus of the present application can be used in many general or special computing system environments or configurations, such as personal computers, server computers, handheld or portable devices, tablet devices, multiprocessor systems, microprocessor-based systems, set-top boxes, programmable consumer terminal devices, network PCs, minicomputers, mainframe computers, and distributed computing environments including any of the above systems or devices.

Exemplarily, the above method and apparatus may be implemented in the form of a computer program, and the computer program may be run on the energy storage device shown in FIG. 5 .

Please refer to Figure 5, which is a schematic diagram of an energy storage device provided in an embodiment of the present application. As shown in Figure 3, the energy storage device 300 includes a processor 310, a memory 320 and a network interface connected through a system bus, wherein the memory 320 may include a volatile storage medium, a non-volatile storage medium and an internal memory.

The non-volatile storage medium can store an operating system and a computer program. The computer program includes program instructions, and when the program instructions are executed, the processor 310 can execute any one of the power management methods.

The processor 310 is used to provide computing and control capabilities to support the operation of the entire energy storage device 300 .

The internal memory provides an environment for the operation of the computer program in the non-volatile storage medium. When the computer program is executed by the processor 310, the processor 310 can execute any one of the power management methods.

The network interface is used for network communication, such as sending assigned tasks, etc. Those skilled in the art can understand that the structure of the energy storage device 300 is only a block diagram of a part of the structure related to the solution of the present application, and does not constitute a limitation on the computer device 300 to which the solution of the present application is applied. The specific energy storage device 300 may include more or fewer components than those shown in the figure, or combine certain components, or have a different arrangement of components.

It should be understood that the processor 310 may be a central processing unit (CPU), or other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. Among them, the general-purpose processor may be a microprocessor or the processor may also be any conventional processor, etc.

An embodiment of the present application also provides a computer-readable storage medium, on which a computer program is stored. The computer program includes program instructions, and when the program instructions are executed, the electric power management method provided in the embodiment of the present application is implemented.

The computer-readable storage medium may be an internal storage unit of the energy storage device 300 described in the foregoing embodiment, such as a hard disk or a memory of the computer device.

The present application also provides a computer-readable storage medium. The storage medium of the present application stores a computer program that can implement all the above-mentioned power management methods, wherein the computer program can be stored in the above-mentioned storage medium in the form of a software product, including a number of instructions to enable a computer device (which can be a personal computer, server, or network device, etc.) or a processor (processor) to execute all or part of the steps of each implementation method of the present application. The aforementioned storage device includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk and other media that can store program codes, or computers, servers, mobile phones, tablets and other devices.

The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any technician familiar with the technical field can easily think of various equivalent modifications or replacements within the technical scope disclosed in the present application, and these modifications or replacements should be included in the protection scope of the present application. Therefore, the protection scope of the present application shall be based on the protection scope of the claims.

Claims

A method for managing electric power, the method being applied to an energy storage device, the method comprising:

After the energy storage device is connected to the home power grid system, injecting a test electrical signal into the home power grid system through the energy storage device;

Acquire a response electrical signal fed back by the home power grid system, wherein the response electrical signal corresponds to the test electrical signal;

Based on the test electrical signal and the response electrical signal, the electrical power of a target electrical load in the home power grid system is calculated, and the target electrical load includes a resistive electrical load and/or a capacitive electrical load.
The method according to claim 1, characterized in that the step of calculating the power consumption of the target power load in the home power grid system based on the test electrical signal and the response electrical signal comprises:

Calculating the equivalent resistance of the target electrical load in the home power grid system according to the test electrical signal and the response electrical signal;

Based on the equivalent resistance and the power supply voltage of the home power grid system, the power consumption of the target power load in the home power grid system is determined.
The method according to claim 2, characterized in that the calculating the equivalent resistance of the target electrical load in the home power grid system according to the test electrical signal and the response electrical signal comprises:

Based on the test electrical signal and the response electrical signal, calculating a port resistance value and a port reactance value of a port of the energy storage device connected to the home power grid;

The equivalent resistance of the target electrical load in the home power grid system is calculated based on the test electrical signal, the port resistance value, and the port reactance value.
The method according to claim 3, characterized in that the calculating the port resistance value and the port reactance value based on the test electrical signal and the response electrical signal comprises:

Among them, V is the voltage value of the response electrical signal; i is the current value of the test electrical signal; Rest is the port resistance value; and Zest is the port reactance value.
The method according to claim 4, characterized in that the calculating the equivalent resistance of the target power load in the home power grid system based on the test electrical signal, the port resistance value and the port reactance value comprises:

Wherein, R is the equivalent resistance; ω is the angular frequency of the test electrical signal; and L is the equivalent inductance of the home power grid system.
The method according to claim 1, characterized in that the energy storage device is connected to a photovoltaic device, and after calculating the household power consumption of the home grid system based on the test electrical signal and the response electrical signal, further comprising:

Obtaining the output power of the photovoltaic device;

When the output power of the photovoltaic device is greater than the power consumption of the target power load in the home power grid system, controlling the photovoltaic device to independently supply power to the home power grid system;

When the output power of the photovoltaic device is less than the power consumption of the target power load in the home power grid system, a power supply request instruction is generated according to the power difference between the output power and the power consumption; the power supply request instruction is configured to request the energy storage device or the power grid to provide an electrical signal with the power difference.
The method according to claim 1 is characterized in that the frequency of the test electrical signal is N times the mains frequency, where N is not an integer.
The method according to claim 1, characterized in that the number of groups of injected test electrical signals can be one group or more groups;

When a plurality of groups of the test electrical signals are injected, the least square method is used to obtain the electrical power of the target electrical load.
An energy storage device, comprising:

A memory and a processor; wherein the memory is connected to the processor, the memory is configured to store a program, and the processor is configured to implement the steps of the electric power management method as described in any one of claims 1 to 7 by running the program stored in the memory.
A computer-readable storage medium, characterized in that the computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the processor implements the steps of the electric power management method as described in any one of claims 1-7.