Locking device of energy storage confluence cabinet

Abstract

An energy storage confluence cabinet locking device comprises an electromagnetic lock arranged on a confluence cabinet door on the side, a battery management system on the side and an electromagnetic lock power-on loop, and the electromagnetic lock power-on loop is connected with a circuit breaker normally-closed auxiliary contact and an unlocking relay normally-open contact of the confluence cabinet on the side in series. A plurality of voltage sampling points of the voltage sampling unit of the current side battery management system are arranged on the input and output copper bars of the current converging cabinet of the current side and are connected with the positive and negative electrodes of the battery side, and the other plurality of voltage sampling points are connected with the positive and negative electrodes of the energy storage AC device side; the plurality of voltage sampling points are in communication connection with a first control unit of the battery management system, the first control unit is connected in series with a first relay coil, and the plurality of voltage sampling points feed back collected battery side total voltage signals and energy storage converter side total voltage signals to the first control unit; the first control unit controls the normally-closed auxiliary contact of the circuit breaker and the normally-open contact of the unlocking relay to be opened and closed according to received signals, then the electromagnetic lock is opened and closed, and when the electromagnetic lock closes the cabinet door of the bus cabinet on the side, the bus cabinet on the side can be powered on. The confluence cabinet is simple in structural design, and can effectively realize anti-electric shock protection when an operator opens the confluence cabinet for operation.

Description

Technical Field

[0001] The utility model relates to a locking device for preventing electric shock, in particular to a locking device for an energy storage combiner cabinet. Background Art

[0002] As the connection hub between the battery side and the energy storage converter side, the combiner cabinet is responsible for the DC combiner and power circuit opening and closing. A DC circuit breaker is installed in the combiner cabinet, and positive and negative input and output copper bars are provided below the circuit breaker. Since the voltage amplitude on the copper bar is in the range of 0.75-1.5 kV and it is exposed in the combiner cabinet, there is a risk of accidental touch for the operator.

[0003] At present, the common locking scheme for energy storage combiner cabinets is to install an electromagnetic lock on the cabinet door, and use the circuit breaker auxiliary contacts to control the electromagnetic lock to open the circuit breaker before the cabinet door can be opened; or a battery management system with analog sampling is used to collect the total voltage on the battery side, and when the voltage sample is greater than the set threshold voltage, the electromagnetic lock is driven to operate to achieve the purpose of locking the cabinet door.

[0004] However, the existing locking scheme has the following problems:

[0005] (1) Using the circuit breaker auxiliary contacts to control the electromagnetic lock only disconnects the battery side from the energy storage converter side, while the input copper bus in the combiner cabinet is still energized, and the operator is still at risk of electric shock.

[0006] (2) Although the analog sampling battery management system can ensure that there is no voltage on the battery side, for energy storage systems with multiple battery stacks connected in parallel on the DC side, since they are connected in parallel on the DC bus side of the energy storage converter, even if the DC circuit breaker of the combiner cabinet is disconnected, the output copper bus in the combiner cabinet is still energized. At this time, the operator still has the risk of electric shock when opening the cabinet door.

[0007] (3) In the scenario where the cabinet door has been opened, if the dispatch center issues a power command at this time or the charge and discharge time node of the preset plan curve is reached, the battery management system and the energy storage inverter will start the power-on process. At this time, the input and output copper bars in the cabinet will be energized again, and the operator will still be at risk of electric shock when opening the cabinet door.

[0008] The existing energy storage combiner lockout scheme mainly uses the live lockout idea of ​​traditional power distribution equipment, but fails to consider the bidirectional charging and discharging characteristics of the energy storage system (both a power source and a load). At the same time, due to the emergence of the DC side parallel connection scheme of multiple battery stacks, the anti-electric shock function has loopholes, which endangers personal safety.

[0009] Therefore, how to design a locking device for an energy storage combiner cabinet, which has a simple structural design and can effectively protect operators from electric shock when opening the combiner cabinet for operation, is a subject that the inventor has devoted himself to studying. Utility Model Content

[0010] The utility model aims to provide a locking device for an energy storage combiner cabinet, which has a simple structural design and can effectively protect operators from electric shock when opening the combiner cabinet for operation.

[0011] In order to achieve the above-mentioned purpose, the technical solution of the utility model is: a locking device for an energy storage combiner cabinet, comprising an electromagnetic lock and a battery management system on this side, which is arranged on the cabinet door of the combiner cabinet on this side, and also includes an electromagnetic lock electrical circuit, wherein the electromagnetic lock electrical circuit is connected in series with the normally closed auxiliary contact of the circuit breaker and the normally open contact of the unlocking relay of the combiner cabinet on this side, and multiple voltage sampling points of the voltage sampling unit of the battery management system on this side are arranged on the input copper bus and the output copper bus of the combiner cabinet on this side, wherein multiple voltage sampling points are connected to the positive and negative electrodes on the battery side, and multiple voltage sampling points are connected to the positive and negative electrodes on the battery side. It is connected to the positive and negative poles of the energy storage AC converter, and multiple voltage sampling points are communicatively connected to the first control unit of the battery management system. The first control unit is connected in series with the first relay coil. Multiple voltage sampling points feed back the collected total voltage signal of the battery side and the total voltage signal of the energy storage converter side to the first control unit. The first control unit controls the opening and closing of the normally closed auxiliary contacts of the circuit breaker and the normally open contacts of the unlocking relay according to the received signals, thereby realizing the opening and closing of the electromagnetic lock. When the electromagnetic lock closes the door of the combiner cabinet on this side, the combiner cabinet on this side can be powered on.

[0012] The utility model provides a locking device for an energy storage combiner cabinet, wherein when the circuit breaker is opened, there is no pressure on the input copper bar and the output copper bar, and the total voltage on the battery side and the total voltage on the energy storage converter side are both less than a safety voltage threshold, the first control unit drives the first relay coil to close, and at the same time the circuit breaker is disconnected, the normally closed auxiliary contact of the circuit breaker closes, so that the electromagnetic lock is electrically unlocked, and the cabinet door of the combiner cabinet on this side is released.

[0013] The utility model discloses a locking device for an energy storage combiner cabinet, wherein the electromagnetic lock is an energized unlocking type electromagnetic lock.

[0014] The utility model provides a locking device for an energy storage combiner cabinet, wherein the battery side includes an energy storage battery compartment on this side and other energy storage battery compartments under the same busbar, the energy storage battery compartment on this side and the other energy storage battery compartments are connected in parallel, the power-on circuit of the energy storage battery compartment on this side and the power-on circuit of the other energy storage battery compartments are connected in series with a door opening locking signal circuit, when the door opening locking signal circuit detects that any one of the combiner cabinet doors is opened, the door opening signal is transmitted to the battery management system on this side and the battery management system of the other energy storage battery compartments, and when the door opening signal is valid, the power-on circuit of the energy storage battery compartment on this side and the power-on circuit of the other energy storage battery compartments are locked.

[0015] The utility model provides a locking device for an energy storage combiner cabinet, wherein the door opening and locking signal circuit comprises a power supply, a cabinet door travel switch and a second relay coil, the power supply, the cabinet door travel switch and the second relay coil are connected in series through a circuit, and the power-on circuit of the energy storage battery compartment on this side and the power-on circuit of the other energy storage battery compartments are respectively connected in series with relay coil conversion contacts controlled to open and close by the second relay coil.

[0016] The utility model provides a locking device for an energy storage combiner cabinet, wherein the power-on circuit of the energy storage battery compartment on this side is connected to the first digital quantity acquisition unit of the battery management system on this side, the first digital quantity acquisition unit is communicatively connected to the first control unit, the power-on circuit of the other energy storage battery compartment is connected to the second digital quantity acquisition unit of the other battery management system, and the second digital quantity acquisition unit is communicatively connected to the second control unit of the other battery management system.

[0017] After adopting the above scheme, the energy storage combiner cabinet locking device of the utility model has the following beneficial effects:

[0018] 1. Use a voltage sampling unit that sets multiple voltage sampling points on the input copper busbar and output copper busbar of the combiner cabinet on this side. This dual-terminal voltage sampling scheme is more suitable for energy storage bidirectional power systems (both power supply and load);

[0019] 2. The requirement of closing the cabinet door is used as a prerequisite for powering on the cabinet, which eliminates the possibility of electric shock to the operator due to sudden power restoration during maintenance.

[0020] 3. By connecting the power-on circuits of the energy storage battery compartments on this side and other energy storage battery compartments in parallel in series with the door opening and locking signal circuit, the loopholes in the operation of the power-on circuits of the existing multiple energy storage battery compartments in parallel are compensated.

[0021] 4. The electromagnetic lock adopts the power-on unlocking type electromagnetic lock, which can avoid the loss of protection function caused by locking circuit failure or secondary power failure. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1This is the electrical circuit diagram of the electromagnetic lock of the combiner cabinet on this side of the energy storage combiner cabinet locking device of the utility model;

[0023] Figure 2 It is a circuit diagram of the power-on circuit of other energy storage battery compartments on the same busbar and the door opening locking signal circuit connected in series on this side of the energy storage combiner locking device of the utility model;

[0024] Figure 3 It is a schematic diagram of the operation of the energy storage combiner cabinet locking device of the utility model to open the cabinet door of the combiner cabinet on this side.

[0025] Number Description:

[0026] 1-Electromagnetic lock 2-Electromagnetic lock power circuit

[0027] 3- Circuit breaker normally closed auxiliary contact 4- Unlocking relay normally open contact

[0028] 5- Voltage sampling unit 6- First control unit

[0029] 7-First relay coil 8-Energy storage battery compartment power-on circuit on this side

[0030] 9-Other energy storage battery compartment power-on circuit 10-Door opening and locking signal circuit

[0031] 11-Power supply 12-Door travel switch

[0032] 13- Second relay coil 14- First relay coil switching contact

[0033] 15- Second relay coil conversion contact 16- First digital quantity acquisition unit

[0034] 17- Second digital quantity acquisition unit 18- Second control unit DETAILED DESCRIPTION

[0035] The present invention is described below based on the embodiments shown in the accompanying drawings. The embodiments disclosed this time can be considered to be illustrative in all aspects and not restrictive. The scope of the present invention is not limited by the description of the following embodiments, but is only shown by the scope of the claims, and includes all variations with the same meaning as the scope of the claims and within the scope of the claims.

[0036] The structure of the energy storage combiner cabinet locking device of the present utility model is described below in conjunction with specific embodiments.

[0037] like Figure 1 As shown, the energy storage combiner locking device of the utility model comprises an electromagnetic lock 1 arranged on the cabinet door of the combiner, a battery management system of the same side and an electromagnetic lock power circuit 2. The electromagnetic lock 1 of the present embodiment is a power-on unlocking type electromagnetic lock.

[0038] The electromagnetic lock electrical circuit 2 is connected in series with the normally closed auxiliary contact 3 of the circuit breaker of the junction box on this side and the normally open contact 4 of the unlocking relay. The battery management system on this side includes a voltage sampling unit 5 and a first control unit 6. The voltage sampling unit 5 includes multiple voltage sampling points. This embodiment adopts four voltage sampling points V1-V4. The four voltage sampling points V1-V4 are arranged on the input copper bus and the output copper bus of the junction box on this side. Two of the voltage sampling points V1 and V2 are electrically connected to the positive and negative poles of the energy storage inverter, and the other two voltage sampling points V3 and V4 are electrically connected to the positive and negative poles of the battery. The four voltage sampling points V1-V4 collect the total voltage U at the input and output ports of the energy storage AC. 1-2 And the total voltage U of the battery input and output ports 3-4 , the four voltage sampling points V1-V4 are connected to the first control unit 6 for communication. The first control unit 6 is connected in series with the first relay coil 7, and the four voltage sampling points V1-V4 collect the total battery voltage U 3-4 And the total voltage U of the energy storage converter 1-2 Feedback is given to the first control unit 6, which controls the opening and closing of the normally closed auxiliary contact 3 of the circuit breaker and the normally open contact 4 of the unlocking relay according to the received signal, thereby realizing the opening and closing of the electromagnetic lock 1. When the circuit breaker is open, the input copper bar and the output copper bar are voltage-free, and the total battery voltage U 3-4 And the total voltage U of the energy storage converter 1-2 When the voltages of the first relay coil 7 and the first control unit 6 drive the first relay coil 7 to close, the circuit breaker is disconnected, and the normally closed auxiliary contact 3 of the circuit breaker closes, so that the electromagnetic lock 1 is unlocked and the cabinet door of the combiner cabinet on this side is released. After the electromagnetic lock 1 closes the cabinet door of the combiner cabinet on this side, the combiner cabinet on this side can be powered on.

[0039] When the door of the combiner cabinet on this side is open and the operator is performing maintenance, in order to prevent the battery management system from receiving a power-on command from the background or other combiners under the same energy storage converter bus in the energy storage system with multiple battery stacks connected in parallel on the DC side from being powered on, causing the combiner cabinet on this side to be energized. Figure 2 As shown, the battery side of this embodiment includes the energy storage battery compartment on this side and other energy storage battery compartments under the same busbar, and the energy storage battery compartment on this side is connected in parallel with other energy storage battery compartments. The power-on circuit 8 of the energy storage battery compartment on this side and the power-on circuit 9 of other energy storage battery compartments are connected in series with the door opening and locking signal circuit 10.

[0040] The door opening and locking signal circuit 10 includes a power supply 11, a door travel switch 12 and a second relay coil 13, which are connected in series through a circuit. The first relay coil switching contact 14 and the second relay coil switching contact 15, which are controlled to be opened and closed by the second relay coil 13, are respectively connected in series in the power-on circuit 8 of the energy storage battery compartment on this side and the power-on circuit 9 of the other energy storage battery compartment.

[0041] The power-on circuit 8 of the energy storage battery compartment on this side is connected to the first digital quantity acquisition unit 16 of the battery management system on this side, and the first digital quantity acquisition unit 16 is communicatively connected to the first control unit 6. The power-on circuit 9 of other energy storage battery compartments is connected to the second digital quantity acquisition unit 17 of other battery management systems, and the second digital quantity acquisition unit 17 is communicatively connected to the second control unit 18 of other battery management systems.

[0042] When the door opening and locking signal circuit 10 detects that the cabinet door of the junction box is opened, the door opening signal is transmitted to the battery management system on this side and the battery management system of other energy storage battery compartments under the same bus. When the door opening signal is valid, the battery management system on this side locks the power-on circuit 8 of the energy storage battery compartment on this side, and the battery management system of other energy storage battery compartments under the same bus locks the power-on circuits of other energy storage battery compartments. Specifically, Figure 2 As shown, when a combiner cabinet door is opened, the door travel switch 12 is closed, the second relay coil 13 is energized, the first relay coil switching contact 14 and the second relay coil switching contact 15 are closed, and the door opening signal is transmitted to the battery management system on this side and the battery management system of other energy storage battery compartments under the same bus respectively. When the signal is valid, the power-on process of the energy storage battery compartment on this side and the power-on process of other energy storage battery compartments under the same bus are locked. In this way, when the combiner cabinet door on any side is opened, the energy storage battery compartment on this side and other energy storage battery compartments under the same bus cannot be powered on, thereby protecting the personal safety of the operator.

[0043] The method for locking the energy storage combiner cabinet using the energy storage combiner cabinet locking device of the utility model is shown in Figure 3 The specific process of using is as follows:

[0044] S1. The operator first issues a command to power off the combiner cabinet on this side through the battery management system on this side;

[0045] S2, open the circuit breaker of the combiner cabinet on this side. If the normally closed auxiliary contact 3 of the circuit breaker is closed, go to step S3; otherwise, go to step S1;

[0046] S3, send a power-off command to all high-voltage boxes on this side;

[0047] S4: After all high-voltage boxes are powered off, if the voltage sampling unit 5 of the battery management system on this side cannot collect the voltage U at the input side of the copper busbar, 3-4 , then go to step S5, otherwise go to step S3;

[0048] S5, then supply power to other energy storage battery compartment combiner cabinets under the same busbar;

[0049] S6: When the DC busbar of the energy storage converter on the local combiner cabinet is not powered, the voltage sampling unit 5 of the battery management system on this side cannot collect the voltage U at the output side of the copper busbar. 1-2, then go to step S7, otherwise go to step S5;

[0050] S7, the first control unit 6 receives the information from the voltage sampling unit 5, drives the first relay coil 7 to be energized, the electromagnetic lock 1 is energized and unlocked, and the cabinet door of the combiner cabinet on this side is opened.

[0051] The energy storage junction cabinet locking device of the utility model adopts a voltage sampling unit 5 that sets four voltage sampling points V1-V4 on the input copper bus and the output copper bus of the junction cabinet on this side. This dual-end voltage sampling scheme is more suitable for energy storage bidirectional power systems (both power sources and loads). The requirement that the cabinet door of the junction cabinet is closed is used as a prerequisite for powering on the junction cabinet, which eliminates the possibility of electric shock to the operator due to sudden power restoration during maintenance. By connecting the parallel power-on circuit 8 of the energy storage battery compartment on this side, the power-on circuit 9 of other energy storage battery compartments and the door opening lock signal circuit 10 in series, the loopholes of the existing parallel power-on circuits of multiple energy storage battery compartments during operation are compensated. The electromagnetic lock 1 adopts a power-on unlocking type electromagnetic lock to avoid the loss of protection function caused by locking circuit failure or secondary power failure.

[0052] The above-described embodiments are merely descriptions of preferred implementation modes of the present invention, and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary engineering and technical personnel in the field shall fall within the protection scope of the claims of the present invention.

Claims

1. A locking device for an energy storage combiner cabinet, comprising an electromagnetic lock arranged on a cabinet door of the combiner cabinet on this side and a battery management system on this side, characterized in that: It also includes an electromagnetic lock power circuit, which is connected in series with the circuit breaker normally closed auxiliary contact and the unlocking relay normally open contact of the local combiner cabinet. Multiple voltage sampling points of the voltage sampling unit of the local battery management system are set on the input copper bus and the output copper bus of the local combiner cabinet, wherein multiple voltage sampling points are connected to the positive and negative poles of the battery side, and multiple voltage sampling points are connected to the positive and negative poles of the energy storage AC converter side. Multiple voltage sampling points are communicatively connected with the first control unit of the battery management system, and the first control unit is connected in series with the first relay coil. Multiple voltage sampling points feed back the collected total voltage signal of the battery side and the total voltage signal of the energy storage converter side to the first control unit, and the first control unit controls the opening and closing of the circuit breaker normally closed auxiliary contact and the unlocking relay normally open contact according to the received signal, thereby realizing the opening and closing of the electromagnetic lock. When the electromagnetic lock closes the cabinet door of the local combiner cabinet, the local combiner cabinet can be powered on.

2. The energy storage combiner cabinet locking device according to claim 1, characterized in that: When the circuit breaker is opened, there is no pressure on the input copper busbar and the output copper busbar, and the total voltage on the battery side and the total voltage on the energy storage converter side are both less than the safety voltage threshold, the first control unit drives the first relay coil to close, and at the same time the circuit breaker is disconnected, and the normally closed auxiliary contact of the circuit breaker is closed, so that the electromagnetic lock is electrically unlocked and the door of the junction box on this side is released.

3. The energy storage combiner cabinet locking device according to claim 1 or 2, characterized in that: The electromagnetic lock is a power-on unlocking type electromagnetic lock.

4. The energy storage combiner cabinet locking device according to claim 1, characterized in that: The battery side includes the energy storage battery compartment on this side and other energy storage battery compartments under the same busbar. The energy storage battery compartment on this side and the other energy storage battery compartments are connected in parallel. The power-on circuit of the energy storage battery compartment on this side and the power-on circuit of the other energy storage battery compartments are connected in series with the door opening and locking signal circuit. When the door opening and locking signal circuit detects that any door of the junction box is opened, the door opening signal is transmitted to the battery management system on this side and the battery management system of the other energy storage battery compartments. When the door opening signal is valid, the power-on circuit of the energy storage battery compartment on this side and the power-on circuit of the other energy storage battery compartments are locked.

5. The energy storage combiner cabinet locking device according to claim 4, characterized in that: The door opening and locking signal circuit includes a power supply, a cabinet door travel switch and a second relay coil. The power supply, the cabinet door travel switch and the second relay coil are connected in series through a circuit. The power-on circuit of the energy storage battery compartment on this side and the power-on circuit of the other energy storage battery compartments are respectively connected in series with relay coil conversion contacts controlled by the second relay coil to open and close.

6. The energy storage combiner cabinet locking device according to claim 4, characterized in that: The power-on circuit of the energy storage battery compartment on this side is connected to the first digital quantity acquisition unit of the battery management system on this side, and the first digital quantity acquisition unit is communicatively connected to the first control unit. The power-on circuit of the other energy storage battery compartment is connected to the second digital quantity acquisition unit of the other battery management system, and the second digital quantity acquisition unit is communicatively connected to the second control unit of the other battery management system.

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