Pole-mounted circuit breaker

Abstract

The invention relates to the field of switches with arc extinguishing devices, in particular to a pole-mounted circuit breaker. The pole-mounted circuit breaker is used for solving the problem that the existing pole-mounted circuit breaker is long in response time of cutting off current during overload or short circuit and is easy to cause equipment damage. The pole-mounted circuit breaker comprises a mechanism box, the mechanism box is provided with three-phase solid-sealed polar poles which are arranged left and right, each solid-sealed polar pole is provided with a top wire inlet end and a bottom wire outlet end, the mechanism box is provided with a fuse corresponding to the rear side of each solid-sealed polar pole, and an isolation disconnecting link is arranged between the wire inlet end of each fuse and the bottom wire outlet end. The mechanism box is provided with an isolation switch operation mechanism which drives the isolation switch to act so as to connect and disconnect the wire inlet end of the fuse and the wire outlet end of the bottom. The wire outlet end of the fuse is the wire outlet end of the main loop. The fuse is fast in response speed and high in reliability, and when the pole-mounted circuit breaker is overloaded and short-circuited, the circuit can be quickly cut off by fusing the fuse wire through the fuse, so that fault expansion is prevented, and equipment damage and maintenance cost are reduced.

Description

Technical Field

[0001] The invention relates to the field of switches with arc extinguishing devices, and in particular to a pole-mounted circuit breaker. Background Art

[0002] A pole-mounted circuit breaker is a switchgear installed on a power line pole, mainly used to quickly cut off the circuit to protect the power system from faults such as short circuits and overloads, to prevent equipment damage and safety accidents such as fires. During maintenance or overhaul, the pole-mounted circuit breaker can isolate the equipment from the power grid to ensure the safety of the staff.

[0003] The Chinese utility model patent with authorization announcement number CN205692757U discloses a vacuum circuit breaker with an insulating knife switch, which includes a mechanism box, on which a three-phase vacuum arc chamber sealed insulating pillar is arranged, the three-phase vacuum arc chamber sealed insulating pillar has a top incoming line end and a bottom outgoing line end, and a mutual inductor is installed on the bottom outgoing line end, and an isolating knife group bracket is arranged on the rear side of the three-phase mechanism box, and an isolating switch operating mechanism and three isolating insulating pull rods connected to the isolating switch operating mechanism are arranged on the isolating knife group bracket, and isolating knife switches are arranged on the upper part of the three isolating insulating pull rods, and an insulating pillar is also arranged on the isolating knife group bracket corresponding to the rear side of the three-phase vacuum arc chamber sealed insulating pillar, the isolating knife switch is located between the inlet end of the insulating pillar and the bottom outgoing line end, and the isolating switch operating mechanism drives the isolating knife switch to conduct and cut off the inlet end of the insulating pillar and the bottom outgoing line end. When in use, the circuit breaker has a large load current. When abnormal conditions such as overload and short circuit occur, if the circuit breaker does not respond in time, the current cannot be cut off in time, and the electrical equipment will be subjected to the impact of abnormal current for a long time, causing equipment damage. Summary of the invention

[0004] The object of the present invention is to provide a pole-mounted circuit breaker to solve the problem that the existing pole-mounted circuit breaker has a long response time to cut off the current when overloaded or short-circuited, which easily causes equipment damage.

[0005] In order to solve the above technical problems, a pole-mounted circuit breaker of the present invention adopts the following technical solutions: The pole-mounted circuit breaker includes a mechanism box, on which are arranged three-phase sealed poles in left and right order, the sealed poles having a top incoming line terminal and a bottom outgoing line terminal, a fuse is provided on the mechanism box at the rear position corresponding to each sealed pole, an isolating knife switch is provided between the fuse incoming line terminal and the bottom outgoing line terminal, the mechanism box is provided with an isolating switch operating mechanism for driving the isolating knife switch to conduct and cut off the fuse incoming line terminal and the bottom outgoing line terminal, and the fuse outgoing line terminal is the outgoing line terminal of the main circuit.

[0006] Furthermore, the fuse is an ejection type fuse.

[0007] Furthermore, the nozzle of the ejection type fuse faces downward.

[0008] Furthermore, the fuse is arranged vertically.

[0009] Furthermore, an insulating connector which cantilevers backwards is provided on the rear side of the mechanism box, and the fuse is installed on the rear side of the mechanism box through the insulating connector.

[0010] Furthermore, the isolating knife switch is a swing-type knife switch, the swing axis of which is located at the bottom outlet terminal, and the inlet terminal of the fuse is provided with an isolating static contact that cooperates with the isolating knife switch.

[0011] Furthermore, a voltage transformer is arranged on the front side of the sealed pole.

[0012] Furthermore, a current transformer is provided at the bottom outlet terminal.

[0013] The present invention improves the prior art by connecting a fuse in series in the circuit of the pole-mounted circuit breaker after the isolating switch to improve the safety and reliability of the pole-mounted circuit breaker. The fuse has the characteristics of fast response speed and high reliability. Thus, when an abnormal current appears in the circuit, the circuit can be quickly cut off by melting the fuse, thereby preventing the fault from expanding. The use of the fuse can reduce the probability of faults, reduce equipment damage and maintenance costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a three-dimensional structural schematic diagram of a pole-mounted circuit breaker of the present invention; Figure 2 for Figure 1 A front view of Figure 3 for Figure 1 Rear view of Figure 4 for Figure 1 A top view of Figure 5 for Figure 1 Right view of .

[0015] In the figure: 1. Mechanism box; 2. Disconnector operating mechanism; 3. Isolation frame; 4. Fuse outlet; 5. Isolation insulation pull rod; 6. Fuse; 7. Voltage transformer; 8. Current transformer; 9. Rain cap; 10. Top incoming terminal; 11. Isolation knife switch; 12. Sealed pole; 13. Insulating connector; 14. Aviation plug interface; 15. Circuit breaker opening and closing indication; 16. Energy storage indication; 17. Circuit breaker energy storage handle; 18. Fuse incoming terminal; 19. Bottom outgoing terminal. DETAILED DESCRIPTION

[0016] The present invention improves the prior art. The core concept of the present invention is: a fuse is connected in series in the circuit of the pole-mounted circuit breaker after the isolating switch. The fuse has the characteristics of fast response speed and high reliability. In this way, when an abnormal current appears in the circuit, once the circuit breaker fails to open in time, the circuit can be quickly cut off by melting the fuse to prevent the fault from expanding. The use of the fuse can reduce the probability of fault occurrence, reduce equipment damage and maintenance costs.

[0017] In view of the above invention concept, the present invention provides a pole mounted circuit breaker including: Figure 1 The mechanism box 1 shown in the figure is provided with three-phase solid-sealed poles 12 arranged on the left and right, and the solid-sealed poles 12 have a top inlet terminal 10 and a bottom outlet terminal 19. The moving and static contacts of the circuit breaker are installed in the solid-sealed poles 12, and the circuit breaker operating mechanism is installed in the mechanism box 1. The moving and static contacts are opened and closed by the circuit breaker operating mechanism. Figure 2 As shown, a circuit breaker opening and closing indication 15 is provided on the front side of the mechanism box 1 to quickly indicate the opening and closing status of the circuit breaker. An energy storage indication 16, a circuit breaker energy storage handle 17 and an aviation plug interface 14 are also provided on the front side of the mechanism box 1. The pole-mounted circuit breaker can be connected to the FTU through the aviation plug 14. In this way, remote control commands can be supported. When the operator operates on site, he can complete the operation through the human-computer interaction interface and check the status of the mechanism in the cabinet in real time. A rain cap 9 is also provided on the top of the sealed pole 12 of this embodiment, so as to effectively prevent rainwater; an energy extraction device is provided inside the sealed pole 12 to extract power.

[0018] The mechanism box 1 is provided with the following at the rear side position corresponding to each sealed pole 12: Figure 3 , Figure 4The fuse 6 shown has an isolating knife switch 11 between the fuse inlet terminal 18 and the bottom outlet terminal 19, and the mechanism box 1 is provided with an isolating switch operating mechanism 2 for driving the isolating knife switch 11 to conduct and cut off the fuse inlet terminal 18 and the bottom outlet terminal 19. The mechanism box 1 of this embodiment includes an isolating frame 3, and the isolating switch operating mechanism 2 includes a transmission mechanism in the isolating frame 3 and an isolating insulating pull rod 5 which is transmission-connected to the transmission mechanism and located on the upper part of the isolating frame 3, and the isolating insulating pull rod 5 is rotationally mounted with the isolating knife switch 11 in the middle part of the isolating knife switch 11. The fuse outlet terminal 4 is the outlet terminal of the main circuit. The pole-mounted circuit breaker is a three-phase three-wire system, and the three-phase conductors are respectively connected to the top inlet terminal 10 on the three-phase solid-sealed pole 12, and the fuse outlet terminal 4 is also respectively connected to the three conductors, and the pole-mounted circuit breaker is connected to the external circuit through the conductors. The fuse 6 has the characteristics of fast response speed and high reliability. After the fuse 6 is set in the pole-mounted circuit breaker, when an abnormal current appears in the circuit, if the circuit breaker is not disconnected in time, the fuse 6 can be melted to quickly cut off the circuit to prevent the fault from expanding. The use of the fuse 6 can reduce the probability of faults, equipment damage and maintenance costs.

[0019] In this embodiment, the fuse 6 is an ejection type fuse. The ejection type fuse has a simple structure, excellent breaking performance and arc extinguishing performance, can extinguish the arc by ejecting gas, and can also quickly cut off a large fault current. In addition, in other embodiments, the fuse can also be an open fuse, a semi-enclosed fuse or a tubular fuse.

[0020] In this embodiment, the nozzle of the jet-type fuse is downward. When the fuse is melted and an arc is generated, the high temperature of the arc decomposes the surrounding gas-generating medium into gas, and forms pressure in the fuse-carrying tube. The arc and gas generated by the melt melting are ejected downward to extinguish the arc. In addition, in other embodiments, the nozzle of the jet-type fuse can also be set upward. In this case, sufficient space must be reserved above the fuse to ensure that the fuse does not affect the upper equipment.

[0021] In this embodiment, the fuse 6 is arranged vertically. In addition, in other embodiments, the fuse 6 can also be installed on the inclined surface of the isolation frame 3 to be inclined.

[0022] In this embodiment, if Figure 5 As shown, an insulating connector 13 cantilevered backward is provided on the rear side of the isolation frame 3, and the fuse 6 is installed on the rear side of the isolation frame 3 through the insulating connector 13. The connector 13 ensures the installation reliability of the fuse 6 and the isolation frame 3. In addition, in other embodiments, the fuse can also be directly installed on the upper surface of the isolation frame, as long as the installation reliability of the fuse is ensured.

[0023] In the present embodiment, the isolating knife switch 11 is a swing-type knife switch, and its swing axis is at the bottom outlet terminal, and the fuse inlet terminal 18 is provided with an isolating static contact that cooperates with the isolating knife switch 11. One end of the isolating knife switch 11 of the present embodiment is hinged on the bottom outlet terminal 19, and the isolating insulating pull rod 5 of the isolating switch operating mechanism 2 moves to realize the swing of the isolating knife switch 11, thereby realizing its opening and closing with the fuse inlet terminal 18 at the other end. Of course, in another embodiment, the isolating knife switch may also be hinged on the fuse inlet terminal, and the isolating insulating pull rod is driven to move by the isolating switch operating mechanism to realize the swing of the isolating knife switch, thereby realizing its opening and closing with the bottom outlet terminal of the sealed pole at the other end. The swing-type knife switch has a simple structure and is easy to operate. In addition, in other embodiments, the isolating knife switch may also be a direct-acting knife switch.

[0024] In this embodiment, the front side of the sealed pole 12 is provided with Figure 2 The voltage transformer 7 shown. The voltage transformer 7 of this embodiment adopts epoxy resin solid insulation, and has the characteristics of high and low temperature resistance, ultraviolet resistance, and aging resistance. The voltage transformer 7 can be used to monitor the voltage change in the circuit and timely detect voltage fluctuations or abnormal conditions.

[0025] In this embodiment, if Figure 1 As shown, a current transformer 8 is provided at the bottom outlet terminal 19. The current transformer 8 can monitor the magnitude and direction of the current in real time. The current signal provided by the current transformer 8 can realize real-time monitoring and early warning of the circuit state, thereby discovering and solving potential problems in advance.

[0026] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. The patent protection scope of the present invention shall be based on the claims. All equivalent structural changes made using the contents of the description and drawings of the present invention should also be included in the protection scope of the present invention.

Claims

1. A pole-mounted circuit breaker, comprising a mechanism box, on which are arranged three-phase solid-sealed poles arranged left and right, the solid-sealed poles having a top inlet terminal and a bottom outlet terminal, characterized in that: A fuse is provided on the mechanism box at the rear side corresponding to each sealed pole, an isolating knife switch is provided between the fuse input terminal and the bottom output terminal, and the mechanism box is provided with an isolating switch operating mechanism for driving the isolating knife switch to connect and disconnect the fuse input terminal and the bottom output terminal, and the fuse output terminal is the output terminal of the main circuit.

2. The pole mounted circuit breaker according to claim 1, characterized in that: The fuse is an ejection type fuse.

3. The pole mounted circuit breaker according to claim 2, characterized in that: The nozzle of the ejector fuse points downward.

4. The pole mounted circuit breaker according to any one of claims 1 to 3, characterized in that: The fuse is arranged vertically.

5. The pole mounted circuit breaker according to any one of claims 1 to 3, characterized in that: An insulating connector which overhangs backwards is arranged on the rear side of the mechanism box, and the fuse is installed on the rear side of the mechanism box through the insulating connector.

6. The pole mounted circuit breaker according to any one of claims 1 to 3, characterized in that: The isolating knife switch is a swinging knife switch, and its swing axis is located at the bottom outlet end. The inlet end of the fuse is provided with an isolating static contact that cooperates with the isolating knife switch.

7. The pole mounted circuit breaker according to any one of claims 1 to 3, characterized in that: A voltage transformer is arranged at the front side of the sealed pole.

8. The pole mounted circuit breaker according to any one of claims 1 to 3, characterized in that: A current transformer is provided at the bottom outlet terminal.

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