Control circuit and method for preventing electrochemical energy storage from reversely transmitting electric energy in light storage plant area

Abstract

The invention discloses a control circuit and method for preventing electrochemical energy storage from reversely transmitting electric energy in a light storage plant area, the method comprises a reverse power tripping circuit and a basic circuit, and the basic circuit comprises a power supply circuit, a closing circuit and a tripping circuit; the reverse power tripping circuit comprises an energy storage system discharge state node, a photovoltaic system power generation state node and a reverse power device tripping node, and the reverse power tripping circuit is connected with a tripping coil circuit unit in the tripping circuit in series. According to the method, the energy storage system discharge state node and the photovoltaic system power generation state node are introduced, and the reverse power device trip control is matched to enable the energy storage system to stop operating only when photovoltaic reverse power occurs in the energy storage system discharge time period, so that the operation stability of the energy storage system is improved while related regulations are met, and the workload of operation and maintenance personnel is reduced; and meanwhile, charging of the energy storage system is not affected, the situation that the energy storage system is insufficiently charged is reduced, and income loss is reduced.

Description

Technical Field

[0001] The present invention relates to the field of circuit control technology, and more specifically, to a control circuit and method for preventing electrochemical energy storage from back-feeding electric energy in a photovoltaic storage plant. Background Art

[0002] With the maturity of lithium iron phosphate battery technology and the gradual decline in battery system prices, user-side electrochemical energy storage systems have quietly emerged in China. As the installed capacity of user-side electrochemical energy storage systems increases day by day, their impact on the power grid is gradually emerging, and power-related management departments are increasingly standardizing the management of user-side electrochemical energy storage systems.

[0003] For user-side electrochemical energy storage systems, the relevant power departments do not allow them to send electricity to the grid. The current mainstream method to prevent energy storage systems from sending electricity back to the grid is to install a load data acquisition device at the user's main incoming line. When reverse power occurs, the "energy storage energy management system" sends a command to the "energy storage bidirectional converter" to reduce the discharge power, thereby preventing energy storage from sending electricity back to the grid. However, power supply departments in various places have successively issued regulations that user-side energy storage projects must install special reverse power devices. When reverse power occurs, the device should directly send a "trip" command to the grid-connected switch of the energy storage system, thereby physically cutting off the energy storage system.

[0004] At present, most user factories are equipped with photovoltaic systems, which are allowed to feed electricity back to the grid to generate revenue. When users fail to absorb enough electricity, the photovoltaic system will feed electricity back to the grid. Although the reverse power device has high reliability, it causes the grid-connected switch of the energy storage system to trip indiscriminately during the entire photovoltaic power generation period, resulting in reduced operating stability of the energy storage system, which is not conducive to the development of user-side energy storage systems. Summary of the invention

[0005] The purpose of the present invention is to provide a control circuit and method for preventing electrochemical energy storage from back-feeding electric energy in a photovoltaic storage plant, which introduces a discharge state node of an energy storage system and a power generation state node of a photovoltaic system, and cooperates with the tripping control of a reverse power device so that the energy storage system is shut down only when photovoltaic reverse power occurs during the discharge period of the energy storage system. While meeting relevant regulations, the operating stability of the energy storage system is improved and the workload of operation and maintenance personnel is reduced; at the same time, it does not affect the charging of the energy storage system, reduces the situation of insufficient charging of the energy storage system and reduces profit losses.

[0006] A first aspect of the present invention provides a control circuit for preventing electrochemical energy storage from back-feeding electric energy in a photovoltaic energy storage plant, comprising the following steps:

[0007] Reverse power trip circuit and basic circuit, where

[0008] The basic circuit includes a power supply circuit, a closing circuit and a tripping circuit;

[0009] The reverse power tripping circuit comprises an energy storage system discharge state node, a photovoltaic system power generation state node and a reverse power device tripping node, wherein the reverse power tripping circuit is connected in series with a tripping coil circuit unit in the tripping circuit.

[0010] In this solution, the energy storage system discharge state node and the photovoltaic system power generation state node are controlled by a preset control device to perform node opening and closing, wherein the preset control device includes a PLC control device.

[0011] In this solution, when the energy storage system is in a discharging state, the energy storage system discharging state node is closed; when the energy storage system is in a charging or static state, the energy storage system discharging state node is opened.

[0012] In this solution, when the photovoltaic system is in a power generation state, the photovoltaic system power generation state node is closed; when the photovoltaic system is in a static or other state, the photovoltaic system power generation state node is opened.

[0013] In this scheme, the power supply circuit includes a control power supply circuit unit and an operation power supply circuit unit; the closing circuit includes a protection closing circuit unit, a closing position monitoring circuit unit, a manual closing circuit unit, a closing coil circuit unit and a remote control closing circuit unit; the tripping circuit includes a remote control tripping circuit unit, a tripping position monitoring circuit unit, a tripping coil circuit unit, a manual tripping circuit unit and a protection tripping circuit unit.

[0014] In this solution, the energy storage system discharge state node, the photovoltaic system power generation state node and the reverse power device tripping node are connected in series to obtain the reverse power tripping circuit.

[0015] In this solution, one side of the reverse power tripping circuit is connected to the input end of the control power supply circuit unit, and the other side is connected to the input end of the tripping coil circuit unit.

[0016] The second aspect of the present invention further provides a control method for preventing electrochemical energy storage from back-feeding electric energy in a photovoltaic storage plant, which is applied to any of the control circuits for preventing electrochemical energy storage from back-feeding electric energy in a photovoltaic storage plant, wherein the method comprises the following steps:

[0017] Detect the charging and discharging status of the energy storage system and the photovoltaic system to control the opening and closing of the energy storage system discharge state node and the photovoltaic system power generation state node, where:

[0018] When the energy storage system is in a discharging state, controlling the energy storage system discharging state node to be closed, and when the energy storage system is in a charging or static state, controlling the energy storage system discharging state node to be opened;

[0019] When the photovoltaic system is in a power generation state, the photovoltaic system power generation state node is controlled to be closed; and when the photovoltaic system is in a stationary state or other states, the photovoltaic system power generation state node is controlled to be opened.

[0020] The third aspect of the present invention further provides a control system for preventing electrochemical energy storage from back-feeding electric energy in a photovoltaic storage plant, comprising a memory and a processor, wherein the memory comprises a control method program for preventing electrochemical energy storage from back-feeding electric energy in a photovoltaic storage plant, and when the control method program for preventing electrochemical energy storage from back-feeding electric energy in a photovoltaic storage plant is executed by the processor, the following steps are implemented:

[0021] Detect the charging and discharging status of the energy storage system and the photovoltaic system to control the opening and closing of the energy storage system discharge state node and the photovoltaic system power generation state node, where:

[0022] When the energy storage system is in a discharging state, controlling the energy storage system discharging state node to be closed, and when the energy storage system is in a charging or static state, controlling the energy storage system discharging state node to be opened;

[0023] When the photovoltaic system is in a power generation state, the photovoltaic system power generation state node is controlled to be closed; and when the photovoltaic system is in a stationary state or other states, the photovoltaic system power generation state node is controlled to be opened.

[0024] The fourth aspect of the present invention provides a computer-readable storage medium, which includes a control method program for preventing electrochemical energy storage from back-feeding electric energy within a photovoltaic storage plant. When the control method program for preventing electrochemical energy storage from back-feeding electric energy within a photovoltaic storage plant is executed by a processor, the steps of a control method for preventing electrochemical energy storage from back-feeding electric energy within a photovoltaic storage plant as described in any of the above items are implemented.

[0025] The present invention discloses a control circuit and method for preventing electrochemical energy storage from back-feeding electric energy in a photovoltaic storage plant, which introduces a discharge state node of the energy storage system and a power generation state node of the photovoltaic system, and cooperates with the tripping control of the reverse power device so that the energy storage system is shut down only when photovoltaic reverse power occurs during the discharge period of the energy storage system, thereby meeting relevant regulations and improving the operating stability of the energy storage system and reducing the workload of operation and maintenance personnel; at the same time, it does not affect the charging of the energy storage system, reduces the situation of insufficient charging of the energy storage system and reduces profit losses. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 A structural diagram of a control circuit for preventing electrochemical energy storage from back-feeding electric energy in a photovoltaic energy storage plant according to the present invention is shown;

[0027] Figure 2 A flow chart showing a control method for preventing electrochemical energy storage from back-feeding electric energy in a photovoltaic energy storage plant according to the present invention;

[0028] Figure 3 A block diagram of a control system for preventing electrochemical energy storage from back-feeding electric energy in a photovoltaic energy storage plant according to the present invention is shown. DETAILED DESCRIPTION

[0029] In order to more clearly understand the above-mentioned purpose, features and advantages of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be noted that the embodiments of the present application and the features in the embodiments can be combined with each other without conflict.

[0030] In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Therefore, the protection scope of the present invention is not limited to the specific embodiments disclosed below.

[0031] Figure 1 A structural diagram of a control circuit for preventing electrochemical energy storage from back-feeding electric energy in a photovoltaic storage plant according to the present application is shown.

[0032] like Figure 1 As shown, the present application discloses a control circuit for preventing electrochemical energy storage from back-feeding electric energy in a photovoltaic storage plant, comprising:

[0033] Reverse power trip circuit and basic circuit, where

[0034] The basic circuit includes a power supply circuit, a closing circuit and a tripping circuit;

[0035] The reverse power tripping circuit comprises an energy storage system discharge state node, a photovoltaic system power generation state node and a reverse power device tripping node, wherein the reverse power tripping circuit is connected in series with a tripping coil circuit unit in the tripping circuit.

[0036] It should be noted that, in this embodiment, a reverse power tripping circuit is newly provided on the traditional basic circuit, which can solve the problem of reverse power generation in the photovoltaic system during the non-discharge period of the energy storage system without causing the energy storage grid-connected switch to trip incorrectly, wherein the energy storage system discharge state node and the photovoltaic system power generation state node are controlled by a preset control device to perform node opening and closing, wherein the preset control device includes a PLC control device.

[0037] Specifically, when the energy storage system is in a discharging state, the energy storage system discharging state node is closed; when the energy storage system is in a charging or static state, the energy storage system discharging state node is opened; when the photovoltaic system is in a power generation state, the photovoltaic system power generation state node is closed; when the photovoltaic system is in a static or other state, the photovoltaic system power generation state node is opened.

[0038] Furthermore, the basic circuit includes a power supply circuit, a closing circuit and a tripping circuit.

[0039] It should be noted that, in this embodiment, Figure 1 As shown, the power supply circuit includes a control power supply circuit unit and an operation power supply circuit unit; the closing circuit includes a protection closing circuit unit, a closing position monitoring circuit unit, a manual closing circuit unit, a closing coil circuit unit and a remote control closing circuit unit; the tripping circuit includes a remote control tripping circuit unit, a tripping position monitoring circuit unit, a tripping coil circuit unit, a manual tripping circuit unit and a protection tripping circuit unit.

[0040] Furthermore, the reverse power tripping circuit includes an energy storage system discharge state node, a photovoltaic system power generation state node and a reverse power device tripping node, wherein the reverse power tripping circuit is connected in series with a tripping coil circuit unit in the tripping circuit.

[0041] It should be noted that in this embodiment, Figure 1 As shown, the energy storage system discharge state node, the photovoltaic system power generation state node and the reverse power device tripping node are connected in series to obtain the reverse power tripping circuit, wherein one side of the reverse power tripping circuit is connected to the input end of the control power supply circuit unit, and the other side is connected to the input end of the tripping coil circuit unit.

[0042] Figure 2 A flow chart of a control method for preventing electrochemical energy storage from back-feeding electric energy in a photovoltaic storage plant area of ​​the present application is shown.

[0043] like Figure 2 As shown, the present application discloses a control method for preventing electrochemical energy storage from back-feeding electric energy in a photovoltaic storage plant area, which is applied to a control circuit for preventing electrochemical energy storage from back-feeding electric energy in a photovoltaic storage plant area as described in any one of the above, wherein the method comprises the following steps:

[0044] S202, detecting the charging and discharging status of the energy storage system and the photovoltaic system to control the opening and closing of the energy storage system discharge status node and the photovoltaic system power generation status node;

[0045] S204, when the energy storage system is in a discharging state, controlling the energy storage system discharging state node to be closed, and when the energy storage system is in a charging or static state, controlling the energy storage system discharging state node to be opened;

[0046] S206, when the photovoltaic system is in a power generation state, controlling the photovoltaic system power generation state node to be closed; and when the photovoltaic system is in a stationary state or other states, controlling the photovoltaic system power generation state node to be opened.

[0047] It should be noted that, since the above embodiment describes that the energy storage system discharge state node and the photovoltaic system power generation state node are controlled by a preset control device to perform node opening and closing, in this embodiment, it is necessary to detect the charging and discharging state of the energy storage system and the photovoltaic system to control the opening and closing of the energy storage system discharge state node and the photovoltaic system power generation state node.

[0048] Specifically, when the energy storage system is in a discharging state, the energy storage system discharge state node is controlled to be closed, and when the energy storage system is in a charging or static state, the energy storage system discharge state node is controlled to be opened; when the photovoltaic system is in a power generation state, the photovoltaic system power generation state node is controlled to be closed; and when the photovoltaic system is in a static or other state, the photovoltaic system power generation state node is controlled to be opened.

[0049] Figure 3 A block diagram of a control system for preventing electrochemical energy storage from back-feeding electric energy in a photovoltaic energy storage plant according to the present invention is shown.

[0050] like Figure 3 As shown, the present invention discloses a control system for preventing electrochemical energy storage from back-feeding electric energy in a photovoltaic storage plant, comprising a memory and a processor, wherein the memory comprises a control circuit program for preventing electrochemical energy storage from back-feeding electric energy in a photovoltaic storage plant, and the control circuit program for preventing electrochemical energy storage from back-feeding electric energy in a photovoltaic storage plant is executed by the processor to implement the following steps:

[0051] Detect the charging and discharging status of the energy storage system and the photovoltaic system to control the opening and closing of the energy storage system discharge state node and the photovoltaic system power generation state node, where:

[0052] When the energy storage system is in a discharging state, controlling the energy storage system discharging state node to be closed, and when the energy storage system is in a charging or static state, controlling the energy storage system discharging state node to be opened;

[0053] When the photovoltaic system is in a power generation state, the photovoltaic system power generation state node is controlled to be closed; and when the photovoltaic system is in a stationary state or other states, the photovoltaic system power generation state node is controlled to be opened.

[0054] It should be noted that, since the above embodiment describes that the energy storage system discharge state node and the photovoltaic system power generation state node are controlled by a preset control device to perform node opening and closing, in this embodiment, it is necessary to detect the charging and discharging state of the energy storage system and the photovoltaic system to control the opening and closing of the energy storage system discharge state node and the photovoltaic system power generation state node.

[0055] Specifically, when the energy storage system is in a discharging state, the energy storage system discharge state node is controlled to be closed, and when the energy storage system is in a charging or static state, the energy storage system discharge state node is controlled to be opened; when the photovoltaic system is in a power generation state, the photovoltaic system power generation state node is controlled to be closed; and when the photovoltaic system is in a static or other state, the photovoltaic system power generation state node is controlled to be opened.

[0056] The fourth aspect of the present invention provides a computer-readable storage medium, which includes a control method program for preventing electrochemical energy storage from back-feeding electric energy within a photovoltaic storage plant. When the control method program for preventing electrochemical energy storage from back-feeding electric energy within a photovoltaic storage plant is executed by a processor, the steps of a control method for preventing electrochemical energy storage from back-feeding electric energy within a photovoltaic storage plant as described in any of the above items are implemented.

[0057] The present invention discloses a control circuit and method for preventing electrochemical energy storage from back-feeding electric energy in a photovoltaic storage plant, which introduces a discharge state node of the energy storage system and a power generation state node of the photovoltaic system, and cooperates with the tripping control of the reverse power device so that the energy storage system is shut down only when photovoltaic reverse power occurs during the discharge period of the energy storage system, thereby meeting relevant regulations and improving the operating stability of the energy storage system and reducing the workload of operation and maintenance personnel; at the same time, it does not affect the charging of the energy storage system, reduces the situation of insufficient charging of the energy storage system and reduces profit losses.

[0058] In the several embodiments provided in the present application, it should be understood that the disclosed devices and methods can be implemented in other ways. The device embodiments described above are only schematic. For example, the division of the units is only a logical function division. There may be other division methods in actual implementation, such as: multiple units or components can be combined, or can be integrated into another system, or some features can be ignored or not executed. In addition, the coupling, direct coupling, or communication connection between the components shown or discussed can be through some interfaces, and the indirect coupling or communication connection of the devices or units can be electrical, mechanical or other forms.

[0059] The units described above as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units; they may be located in one place or distributed on multiple network units; some or all of the units may be selected according to actual needs to achieve the purpose of the present embodiment.

[0060] In addition, all functional units in the embodiments of the present invention may be integrated into one processing unit, or each unit may be separately used as a unit, or two or more units may be integrated into one unit; the above-mentioned integrated units may be implemented in the form of hardware or in the form of hardware plus software functional units.

[0061] A person of ordinary skill in the art can understand that: all or part of the steps of implementing the above method embodiments can be completed by hardware related to program instructions, and the aforementioned program can be stored in a computer-readable storage medium. When the program is executed, it executes the steps of the above method embodiments; and the aforementioned storage medium includes: mobile storage devices, read-only memories (ROM, Read-Only Memory), random access memories (RAM, Random Access Memory), magnetic disks or optical disks, and other media that can store program codes.

[0062] Alternatively, if the above-mentioned integrated unit of the present invention is implemented in the form of a software function module and sold or used as an independent product, it can also be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the embodiment of the present invention can be essentially or partly reflected in the form of a software product that contributes to the prior art. The computer software product is stored in a storage medium and includes several instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the methods described in each embodiment of the present invention. The aforementioned storage medium includes: various media that can store program codes, such as mobile storage devices, ROM, RAM, magnetic disks or optical disks.

Claims

1. A control circuit for preventing electrochemical energy storage from back-feeding electric energy in a photovoltaic energy storage plant, characterized in that: The following steps are involved: Reverse power trip circuit and basic circuit, where The basic circuit includes a power supply circuit, a closing circuit and a tripping circuit; The reverse power tripping circuit comprises an energy storage system discharge state node, a photovoltaic system power generation state node and a reverse power device tripping node, wherein the reverse power tripping circuit is connected in series with a tripping coil circuit unit in the tripping circuit.

2. A control circuit for preventing electrochemical energy storage from back-feeding electric energy in a photovoltaic power plant according to claim 1, characterized in that: The energy storage system discharge state node and the photovoltaic system power generation state node are controlled by a preset control device to perform node opening and closing, wherein the preset control device includes a PLC control device.

3. A control circuit for preventing electrochemical energy storage from back-feeding electric energy in a photovoltaic power plant according to claim 2, characterized in that: When the energy storage system is in a discharging state, the energy storage system discharging state node is closed; when the energy storage system is in a charging or static state, the energy storage system discharging state node is open.

4. A control circuit for preventing electrochemical energy storage from back-feeding electric energy in a photovoltaic power plant according to claim 3, characterized in that: When the photovoltaic system is in the power generation state, the photovoltaic system power generation state node is closed; when the photovoltaic system is in a static or other state, the photovoltaic system power generation state node is open.

5. A control circuit for preventing electrochemical energy storage from back-feeding electric energy in a photovoltaic power plant according to claim 4, characterized in that: The power supply circuit includes a control power supply circuit unit and an operation power supply circuit unit; the closing circuit includes a protection closing circuit unit, a closing position monitoring circuit unit, a manual closing circuit unit, a closing coil circuit unit and a remote control closing circuit unit; the tripping circuit includes a remote control tripping circuit unit, a tripping position monitoring circuit unit, a tripping coil circuit unit, a manual tripping circuit unit and a protection tripping circuit unit.

6. A control circuit for preventing electrochemical energy storage from back-feeding electric energy in a photovoltaic power plant according to claim 5, characterized in that: The energy storage system discharge state node, the photovoltaic system power generation state node and the reverse power device tripping node are connected in series to obtain the reverse power tripping circuit.

7. A control circuit for preventing electrochemical energy storage from back-feeding electric energy in a photovoltaic power plant according to claim 6, characterized in that: One side of the reverse power trip circuit is connected to the input end of the control power supply circuit unit, and the other side is connected to the input end of the trip coil circuit unit.

8. A control method for preventing electrochemical energy storage from back-feeding electric energy in a photovoltaic power plant, characterized in that: A control circuit for preventing electrochemical energy storage from back-feeding electric energy in a photovoltaic power plant area as described in any one of claims 1 to 7, wherein the method comprises the following steps: Detect the charging and discharging status of the energy storage system and the photovoltaic system to control the opening and closing of the energy storage system discharge state node and the photovoltaic system power generation state node, where: When the energy storage system is in a discharging state, controlling the energy storage system discharging state node to be closed, and when the energy storage system is in a charging or static state, controlling the energy storage system discharging state node to be opened; When the photovoltaic system is in a power generation state, the photovoltaic system power generation state node is controlled to be closed; and when the photovoltaic system is in a stationary state or other states, the photovoltaic system power generation state node is controlled to be opened.

9. A control system for preventing electrochemical energy storage from back-feeding electricity in a photovoltaic power plant, characterized in that: The invention comprises a memory and a processor, wherein the memory comprises a control method program for preventing electrochemical energy storage from transmitting electric energy backwards in a photovoltaic storage plant area, and the control method program for preventing electrochemical energy storage from transmitting electric energy backwards in a photovoltaic storage plant area is executed by the processor to implement the following steps: Detect the charging and discharging status of the energy storage system and the photovoltaic system to control the opening and closing of the energy storage system discharge state node and the photovoltaic system power generation state node, where: When the energy storage system is in a discharging state, controlling the energy storage system discharging state node to be closed, and when the energy storage system is in a charging or static state, controlling the energy storage system discharging state node to be opened; When the photovoltaic system is in a power generation state, the photovoltaic system power generation state node is controlled to be closed; and when the photovoltaic system is in a stationary state or other states, the photovoltaic system power generation state node is controlled to be opened.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium includes a control method program for preventing electrochemical energy storage from back-feeding electric energy within a photovoltaic storage plant. When the control method program for preventing electrochemical energy storage from back-feeding electric energy within a photovoltaic storage plant is executed by a processor, the steps of a control method for preventing electrochemical energy storage from back-feeding electric energy within a photovoltaic storage plant as described in claim 8 are implemented.

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