A shock prevention device for misoperation of a direct current switch cabinet
Patent Information
- Application Number
- CN202522294199.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-10-30
- Publication Date
- 2026-10-27
- Estimated Expiration
- 2035-10-30
AI Technical Summary
[0003]线路测试装置一般装设于开关柜上，通过一次电缆与主回路相连，其一端连接于直流正母线，一端连接于馈出端(图1)；该回路在馈线柜已送电时由于操作人员按规范不能操作开关柜，所以不会发生触电事故；但在馈线柜完成停电操作且手车拉出后，按常规此时操作人员是可以打开柜门并进入开关柜内进行检修和维护操作的，但由于该回路中的接触器上桩头是与直流正母线进行连接，此时本柜停电并拉出手车后，仍存在两种触电风险：一、接触器的上桩头仍是带电的，人员如触碰接触器上桩头则会导致触电；二、接触器此时虽按指令分开，但由于其未有可见断口，因其开断特性，极易出现主触头粘连，而机构已分开的断开假象，让操作人员误认为测试回路已断开，从而产生线路上无电的错误判断，进而在实施检修维护操作中导致触电，该现象已在工程应用中真实发生过，为解决上述两种可能出现的触电风险提出一种直流开关柜误操作的防触电装置
[0010]本实用新型，当馈线柜通电时，断路器小车插入柜内，使得防触电触头与防触电触头盒内端子连接，实现测试回路的导通；当停电时，断路器小车拖出柜内，使得防触电触头与防触电触头盒内端子脱开，实现测试回路的断开，从而实现馈线柜停电后，线路测试回路可靠有效断开，整个测试回路及馈出线路上无电，有效防止触电事故的发生。
Smart Images
Figure CN224908798U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of DC switchgear anti-electric shock technology, specifically an anti-electric shock device for DC switchgear misoperation. Background Technology
[0002] In subway DC traction power supply systems, line faults and the large currents generated during train start-up and shutdown are always significant threats to safe operation. Therefore, preventing DC fast circuit breakers from directly closing on faulty circuits is crucial for ensuring safe operation. DC feeder switches in traction substations are generally equipped with line short-circuit detection and testing systems. Currently, in China, DC fast circuit breakers undergo line testing before closing. If the line test is successful, the circuit breaker closes; conversely, if the line test fails, a short circuit is considered to still exist on the operating line, and to avoid the circuit breaker being subjected to short-circuit current again, it will not reclose.
[0003] Line testing equipment is typically installed on the switchgear and connected to the main circuit via a primary cable. One end of the cable is connected to the DC positive bus, and the other end is connected to the feeder. Figure 1 This circuit prevents electric shock accidents when the feeder cabinet is energized, as operators are prohibited from operating the switchgear according to regulations. However, after the feeder cabinet is de-energized and the trolley is pulled out, operators can normally open the cabinet door and enter the switchgear for inspection and maintenance. But since the contactor terminals in this circuit are connected to the DC positive bus, there are still two risks of electric shock after the cabinet is de-energized and the trolley is pulled out: 1. The contactor terminals are still energized, and touching them will result in electric shock; 2. Although the contactor is separated according to instructions, it has no visible break. Due to its breaking characteristics, the main contacts are easily stuck together, creating the illusion of separation. This can lead operators to mistakenly believe that the test circuit is disconnected, resulting in a false judgment that there is no power on the line, and thus electric shock during inspection and maintenance. This phenomenon has actually occurred in engineering applications. To address these two potential risks of electric shock, an anti-electric shock device for the misoperation of DC switchgear is proposed. Utility Model Content
[0004] The purpose of this utility model is to provide an anti-electric shock device for malfunctions of DC switchgear, so as to solve the problems mentioned in the background art.
[0005] To solve the above-mentioned technical problems, this utility model provides the following technical solution: an anti-electric shock device for misoperation of DC switchgear, comprising an anti-electric shock contact and an anti-electric shock contact box. The anti-electric shock contact is fixedly installed on the circuit breaker trolley of the DC switchgear, and the anti-electric shock contact box is fixedly installed in the lower part of the rear cable compartment of the DC switchgear. The anti-electric shock contact is connected to the contacts on the circuit breaker trolley via a primary cable. After the contacts on the circuit breaker trolley are pushed into the switchgear with the circuit breaker trolley, they are connected to the DC positive busbar inside the cabinet. The terminals inside the anti-electric shock contact box are connected to the upper terminals of the contactor in the upper rear line testing device of the switchgear via a cable. The upper terminals of the contactor in the line testing device are simultaneously connected to the DC negative busbar inside the cabinet.
[0006] Preferably, the head structure of the anti-electric shock contact is adapted to the interface structure of the terminals inside the anti-electric shock contact box.
[0007] Preferably, the anti-electric shock contact box is connected to the cabinet at the bottom of the rear cable compartment of the DC switch cabinet through a fixed structure, and corresponds to the anti-electric shock contact on the circuit breaker trolley.
[0008] Preferably, the anti-electric shock contact is connected to the contact on the circuit breaker trolley via a primary cable.
[0009] Compared with the prior art, the beneficial effects achieved by this utility model are:
[0010] This invention allows for the following: When the feeder cabinet is powered on, the circuit breaker trolley is inserted into the cabinet, connecting the anti-electric shock contacts to the terminals inside the anti-electric shock contact box, thus enabling the test circuit to conduct; when the power is off, the circuit breaker trolley is pulled out of the cabinet, disengaging the anti-electric shock contacts from the terminals inside the anti-electric shock contact box, thus disconnecting the test circuit. This ensures that after the feeder cabinet is powered off, the line test circuit is reliably and effectively disconnected, and there is no power on the entire test circuit and feeder lines, effectively preventing electric shock accidents. Attached Figure Description
[0011] Figure 1 This is a schematic diagram of the structure without the anti-electric shock assembly.
[0012] Figure 2 A schematic diagram of the structure after installing the anti-electric shock combination device;
[0013] Figure 3 A schematic diagram of the DC cabinet anti-electric shock combination device;
[0014] Figure 4 Schematic diagram of the anti-electric shock contact structure;
[0015] Figure 5 A schematic diagram of the structure of the contact box for preventing electric shock.
[0016] Among them: 1. Anti-electric shock contact; 2. Anti-electric shock contact box; 3. DC positive busbar; 4. DC negative busbar; 5. Line testing device; 6. Contact on circuit breaker trolley. Detailed Implementation
[0017] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.
[0018] This utility model provides the following technical solution:
[0019] Please see Figure 2 , Figure 3 , Figure 4 and Figure 5 An electric shock protection device for malfunction of DC switchgear includes an electric shock protection contact 1 and an electric shock protection contact box 2. The electric shock protection contact 1 is fixedly installed on the circuit breaker trolley of the DC switchgear, and the electric shock protection contact box 2 is fixedly installed in the lower part of the rear cable compartment of the DC switchgear. The electric shock protection contact 1 is connected to the contact 6 on the circuit breaker trolley through a primary cable. After the contact 6 on the circuit breaker trolley is pushed into the switchgear with the circuit breaker trolley, it is connected to the DC positive busbar 3 inside the cabinet. The terminals inside the electric shock protection contact box 2 are connected to the upper terminal of the contactor in the upper rear line test device 5 of the switchgear through a cable. The upper terminal of the contactor in the line test device 5 is also connected to the DC negative busbar 4 inside the cabinet.
[0020] The head structure of the anti-electric shock contact 1 is compatible with the interface structure of the terminals inside the anti-electric shock contact box 2.
[0021] The anti-electric shock contact box 2 is connected to the cabinet at the bottom of the rear cable compartment of the DC switch cabinet through a fixed structure, and corresponds to the anti-electric shock contact 1 on the circuit breaker trolley.
[0022] The anti-electric shock contact 1 is connected to the contact 6 on the circuit breaker trolley via a primary cable.
[0023] Through the above technical solution, the anti-electric shock contact 1 is fixed on the circuit breaker trolley of the DC switchgear and moves synchronously with the push-in and pull-out of the circuit breaker trolley, serving as the movable connection end of the test circuit. The anti-electric shock contact box 2 is fixed in the lower part of the rear cable compartment of the DC switchgear, its position is fixed, and it serves as the fixed connection end of the test circuit. It precisely corresponds to the anti-electric shock contact 1 on the circuit breaker trolley to ensure that the two can accurately connect or disconnect when the trolley is pushed or pulled. The device is integrated into the original circuit test system through cable connection. The specific path is: DC positive busbar 3 in the cabinet → contact 6 on the circuit breaker trolley → primary cable → anti-electric shock contact 1 → terminal inside the anti-electric shock contact box 2 after connection → cable → contactor terminal of the circuit test device 5 → DC negative busbar 4 in the cabinet. It does not change the core function of the original circuit test device, only through the anti-electric shock assembly. The circuit breaker assembly adds a physical on / off control point for the circuit, controlled by the displacement of the circuit breaker trolley. Since the head structure of the anti-electric shock contact 1 is compatible with the interface structure of the terminals inside the anti-electric shock contact box 2, when the circuit breaker trolley is pushed in, the two can be tightly connected, avoiding poor contact that could cause the circuit test circuit to be broken, ensuring that the circuit test before the circuit breaker is closed is carried out normally. When the circuit breaker trolley is pulled out, the two can be completely separated, with no half-contact state, ensuring that the test circuit is completely disconnected from the positive busbar end to avoid residual energization, ensuring that the position of the contact box 2 is fixed and will not be displaced due to switch cabinet vibration, operation, etc., and always maintains coaxial correspondence with the anti-electric shock contact 1 on the circuit breaker trolley, avoiding the contact 1 and contact box 2 from jamming when the trolley is pushed in due to positional deviation, affecting circuit conduction, or residual contact when disconnected, resulting in the circuit not being de-energized.
[0024] In actual operation, when this device is in use and the feeder cabinet is powered on, the circuit breaker trolley is inserted into the cabinet, connecting the anti-electric shock contact 1 to the terminals inside the anti-electric shock contact box 2, thus enabling the test circuit to conduct. When the power is off, the circuit breaker trolley is pulled out of the cabinet, disengaging the anti-electric shock contact 1 from the terminals inside the anti-electric shock contact box 2, thus disconnecting the test circuit. This ensures that after the feeder cabinet is powered off, the line test circuit is reliably and effectively disconnected, and there is no power on the entire test circuit and feeder line, effectively preventing electric shock accidents.
[0025] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations may be made to these embodiments without departing from the principles and spirit, the scope of which is defined by the appended claims and their equivalents.
Claims
1. A device for preventing electric shock due to misoperation of a DC switchgear, comprising an anti-electric shock contact (1) and an anti-electric shock contact box (2), characterized in that: The anti-electric shock contact (1) is fixedly installed on the circuit breaker trolley of the DC switch cabinet. The anti-electric shock contact box (2) is fixedly installed in the lower part of the rear cable compartment of the DC switch cabinet. The anti-electric shock contact (1) is connected to the contact (6) on the circuit breaker trolley through a primary cable. After the contact (6) on the circuit breaker trolley is pushed into the switch cabinet with the circuit breaker trolley, it is connected to the DC positive bus (3) inside the cabinet. The terminals inside the anti-electric shock contact box (2) are connected to the contactor terminal in the upper rear line test device (5) of the switch cabinet through a cable. The contactor terminal in the line test device (5) is also connected to the DC negative bus (4) inside the cabinet.
2. The anti-electric shock device for misoperation of a DC switchgear according to claim 1, characterized in that: The head structure of the anti-electric shock contact (1) is adapted to the interface structure of the terminals inside the anti-electric shock contact box (2).
3. The anti-electric shock device for malfunction of a DC switchgear according to claim 1, characterized in that: The anti-electric shock contact box (2) is connected to the cabinet at the bottom of the rear cable compartment of the DC switch cabinet through a fixed structure, and corresponds to the anti-electric shock contact (1) on the circuit breaker trolley.
4. The anti-electric shock device for misoperation of a DC switchgear according to claim 1, characterized in that: The anti-electric shock contact (1) is connected to the contact (6) on the circuit breaker trolley via a primary cable.