Energy storage system grid-connected and off-grid integrated test equipment

Abstract

The utility model discloses grid-connected and off-grid integrated test equipment for an energy storage system. The grid-connected and off-grid integrated test equipment comprises an input switch, an input filter, a rectifier, an inverter, an output filter, an AC / DC converter and a battery, the input end of the input switch is connected with a power grid, the output end of the input switch is connected with the input end of the input filter, the output end of the input filter is connected with the alternating-current side of the rectifier, the inverter is connected with the rectifier through a direct-current bus, and the alternating-current side of the inverter is connected with the input end of the output filter. The output end of the output filter is connected with the input end of the AC / DC converter through the grid-connected and off-grid mode change-over switch, the output end of the output filter is connected with the input end of the tested energy storage equipment, and the output end of the AC / DC converter is connected with a battery; according to the test equipment, the grid-connected and off-grid mode change-over switch is controlled, and the change of a control mode is matched, so that one set of equipment not only has a grid-connected test function of the energy storage system, but also has an off-grid test function of the energy storage system.

Description

Technical Field

[0001] The utility model relates to the technical field of power grid detection, and in particular to an integrated on-grid and off-grid testing device for an energy storage system. Background Art

[0002] With the rapid development of the electrochemical energy storage industry, the models and specifications of electrochemical energy storage products are increasing. In order to standardize the electrochemical energy storage industry market and improve the stability of power grid operation, it is necessary to test the grid-connected performance and off-grid performance of electrochemical energy storage products. Grid-connected testing and off-grid testing are important means to test the performance of an electrochemical energy storage system. In order to conduct grid-connected testing and off-grid testing of electrochemical energy storage systems, special testing equipment is required. The testing equipment of the prior art often only has the grid-connected detection function or only has the off-grid detection function. Test devices for grid-connected detection functions, such as various fixed or mobile grid-connected test devices, can only perform voltage adaptability tests, harmonic adaptability tests, high and low voltage fault ride-through tests and other functions in grid-connected performance tests. This type of device cannot simulate load changes and cannot realize off-grid characteristic tests of electrochemical energy storage devices. Test devices for off-grid detection functions, such as electronic loads of various power levels, can simulate load changes within the designed power range to realize off-grid performance tests of electrochemical energy storage devices, but cannot perform voltage adaptability tests, harmonic adaptability tests, high and low voltage fault ride-through tests and other functions in grid-connected performance tests. In summary, since there is no equipment with both detection functions, the detection efficiency of the electrochemical energy storage device is limited, and multiple detection devices also cause a waste of resources and space. Utility Model Content

[0003] The technical problem to be solved by the utility model is to propose an integrated on-grid and off-grid testing device for an energy storage system. The on-grid and off-grid testing device for an energy storage system controls an on-grid and off-grid mode switching switch and cooperates with the change of the control mode to achieve a set of equipment with both on-grid testing function and off-grid testing function of the energy storage system.

[0004] In order to solve the above technical problems, the utility model provides an integrated on-grid and off-grid test equipment for an energy storage system, including an input switch, an input filter, a rectifier, an inverter, an output filter, an AC / DC converter and a battery; the input end of the input switch is connected to the power grid, the output end of the input switch is connected to the input end of the input filter, the output end of the input filter is connected to the AC side of the rectifier, the inverter is connected to the rectifier through a DC bus, the AC side of the inverter is connected to the input end of the output filter, the output end of the output filter is connected to the input end of the AC / DC converter through an on-grid and off-grid mode switching switch, the output end of the output filter is connected to the input end of the energy storage device under test, and the output end of the AC / DC converter is connected to the battery.

[0005] Preferably, when the test device operates in the grid-connected test mode, the grid-connected and off-grid mode switching switch is in an off state, the AC / DC converter and the battery are not working, and the energy storage device under test is in a grid-connected operation state.

[0006] Preferably, when the test device operates in the off-grid test mode, the on-grid and off-grid mode switching switch is in a closed state, the AC / DC converter and the battery are connected to the output filter line, the energy storage device under test is in an off-grid operation state, and the electric energy released by the device is converted by the AC / DC converter and finally absorbed by the battery.

[0007] Preferably, the rectifier and the inverter both adopt two-level converters or multi-level converters.

[0008] Preferably, the output filter includes an output transformer and a three-phase filter capacitor.

[0009] Preferably, the input filter includes a three-phase filter inductor and a three-phase filter capacitor.

[0010] Preferably, the AC / DC converter is used to convert alternating current and direct current, so that the electric energy released from the energy storage device under test is stored in the battery, or the electric energy in the battery is released to the energy storage device under test, or the electric energy in the battery is fed back to the power grid via the output filter, inverter, rectifier, input filter and input switch.

[0011] After adopting the above equipment, the energy storage system on-grid and off-grid integrated test equipment includes an input switch, an input filter, a rectifier, an inverter, an output filter, an AC / DC converter and a battery; the input end of the input switch is connected to the power grid, the output end of the input switch is connected to the input end of the input filter, the output end of the input filter is connected to the AC side of the rectifier, the inverter is connected to the rectifier through a DC bus, the AC side of the inverter is connected to the input end of the output filter, the output end of the output filter is connected to the input end of the AC / DC converter through an on-grid and off-grid mode switching switch, the output end of the output filter is connected to the input end of the energy storage device under test, and the output end of the AC / DC converter is connected to the battery; the energy storage system on-grid and off-grid integrated test equipment realizes that a set of equipment has both on-grid test function and off-grid test function of the energy storage system by controlling the on-grid and off-grid mode switching switch and cooperating with the change of the control mode. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 This is the overall circuit of an energy storage system on-grid and off-grid integrated test equipment of the utility model Figure 1 ;

[0013] Figure 2 This is the overall circuit of an energy storage system on-grid and off-grid integrated test equipment of the utility model Figure 2 .

[0014] The realization of the purpose, functional features and advantages of this application will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0015] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present application clearer and more understandable, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0016] In the description of the present application, it should be understood that the orientations or positional relationships indicated by the terms "center", "upper", "lower", "front", "back", "left", "right", etc. are based on the orientations or positional relationships shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present application. In addition, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

[0017] Embodiment 1

[0018] See also Figure 1 and Figure 2 , Figure 1 This is the overall circuit of an energy storage system on-grid and off-grid integrated test equipment of the utility model Figure 1 ; Figure 2 This is the overall circuit of an energy storage system on-grid and off-grid integrated test equipment of the utility model Figure 2 ;

[0019] The present embodiment discloses an integrated on-grid and off-grid test device for an energy storage system, comprising an input switch, an input filter 10, a rectifier 11, an inverter 12, an output filter 13, an AC / DC converter 15 and a battery 16; the input end of the input switch is connected to the power grid, the output end of the input switch is connected to the input end of the input filter 10, the output end of the input filter is connected to the AC side of the rectifier 11, the inverter 12 is connected to the rectifier 11 through a DC bus, the AC side of the inverter 12 is connected to the input end of the output filter 13, the output end of the output filter 13 is connected to the input end of the AC / DC converter 15 through an on-grid and off-grid mode switching switch, the output end of the output filter 13 is connected to the input end of the energy storage device 14 under test, and the output end of the AC / DC converter 15 is connected to the battery 16.

[0020] Embodiment 2

[0021] This embodiment is based on the first embodiment. In this embodiment, when the test device is running in the grid-connected test mode, the grid-connected and off-grid mode switch is in the disconnected state, the AC / DC converter 15 and the battery 16 are not working, and the energy storage device 14 under test is in the grid-connected operation state;

[0022] When the test equipment operates in the off-grid test mode, the on-grid and off-grid mode switching switch is in a closed state, the AC / DC converter 15 and the battery 16 are connected to the line of the output filter 13, and the energy storage device 14 under test is in an off-grid operation state. The electric energy released by the device is converted by the AC / DC converter 15 and finally absorbed by the battery 16.

[0023] Embodiment 3

[0024] This embodiment is based on the first embodiment. In this embodiment, the rectifier 11 and the inverter 12 both use the same two-level converter or multi-level converter.

[0025] The output filter 13 includes an output transformer and a three-phase filter capacitor, and the input filter 10 includes a three-phase filter inductor and a three-phase filter capacitor.

[0026] Embodiment 4

[0027] This embodiment is based on the first embodiment. In this embodiment, the AC / DC converter 15 is used to convert alternating current and direct current, so that the electric energy released from the energy storage device 14 under test is stored in the battery or the electric energy in the battery is released to the energy storage device under test or the electric energy in the battery is fed back to the power grid via the output filter 13, the inverter 12, the rectifier 11, the input filter 10 and the input switch.

[0028] The energy storage system on-grid and off-grid integrated test equipment controls the on-grid and off-grid mode switching switch and cooperates with the change of control mode to achieve a set of equipment with both on-grid test function and off-grid test function of the energy storage system.

[0029] The preferred embodiments of the present application are described above with reference to the accompanying drawings, but the scope of the present application is not limited thereby. Any modification, equivalent substitution and improvement made by a person skilled in the art without departing from the scope and essence of the present application shall be within the scope of the present application.

Claims

1. An integrated test device for an energy storage system on and off the grid, characterized in that: The invention comprises an input switch, an input filter, a rectifier, an inverter, an output filter, an AC / DC converter and a battery; the input end of the input switch is connected to the power grid, the output end of the input switch is connected to the input end of the input filter, the output end of the input filter is connected to the AC side of the rectifier, the inverter is connected to the rectifier through a DC bus, the AC side of the inverter is connected to the input end of the output filter, the output end of the output filter is connected to the input end of the AC / DC converter through an on-grid and off-grid mode switching switch, the output end of the output filter is connected to the input end of the energy storage device to be tested, and the output end of the AC / DC converter is connected to the battery.

2. The energy storage system on-grid and off-grid integrated test equipment according to claim 1, characterized in that: When the test device operates in the grid-connected test mode, the grid-connected and off-grid mode switching switch is in an off state, the AC / DC converter and the battery are not working, and the energy storage device under test is in a grid-connected operation state.

3. The energy storage system on-grid and off-grid integrated testing equipment according to claim 1, characterized in that: When the test device operates in the off-grid test mode, the on-grid and off-grid mode switching switch is in a closed state, the AC / DC converter and the battery are connected to the output filter line, the energy storage device under test is in an off-grid operation state, and the electric energy released by the device is converted by the AC / DC converter and finally absorbed by the battery.

4. The energy storage system on-grid and off-grid integrated testing equipment according to claim 1, characterized in that: The rectifier and the inverter both adopt two-level converters or multi-level converters.

5. The energy storage system on-grid and off-grid integrated testing equipment according to claim 1, characterized in that: The output filter includes an output transformer and a three-phase filter capacitor.

6. The energy storage system on-grid and off-grid integrated testing equipment according to claim 1, characterized in that: The input filter includes a three-phase filter inductor and a three-phase filter capacitor.

7. The energy storage system on-grid and off-grid integrated testing equipment according to claim 1, characterized in that: The AC / DC converter is used to convert alternating current and direct current, so that the electric energy released from the energy storage device under test is stored in the battery, or the electric energy in the battery is released to the energy storage device under test, or the electric energy in the battery is fed back to the power grid via the output filter, inverter, rectifier, input filter and input switch.

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