Circuit breaker and insulation method thereof

Abstract

The invention discloses an insulation structure used for a moving part and a vacuum circuit breaker including the insulation structure. The moving part is contained in an insulation shell body and can move between at least two positions. The moving part comprises an electriferous first end, a grounded second end opposite to the first end and an insulation portion arranged between the first end and the second end, wherein the first end is insulated with the second end through the insulation portion. The moving part is characterized by further comprising an extensible insulating part. The inner periphery side of the insulating part is connected with the periphery of the insulation portion in an enclosing and air seal mode. The peripheral side of the insulation portion is connected with the insulation shell body in an air seal mode so that the first end is separated from the second end in the air seal mode.

Description

technical field [0001] The invention relates to a circuit breaker, especially a medium-high voltage vacuum circuit breaker, and relates to an insulation structure and an insulation method for the vacuum circuit breaker. Background technique [0002] A circuit breaker is an electrical device commonly used in a circuit, which is used to disconnect the circuit in the event of a fault such as overload or overheating in the circuit. Circuit breakers can be divided into low voltage circuit breakers and high voltage circuit breakers according to their rated voltage. High-voltage circuit breakers are usually used in circuits with a voltage exceeding 1000V. They can not only cut off or close the no-load current and load current in the high-voltage circuit, but also cut off the overload current and short-circuit current through the function of the relay protection device when the system fails. . Commonly used high-voltage circuit breakers include oil circuit breakers (more oil circu...

AI Technical Summary

Problems solved by technology

[0006] However, this traditional high-voltage circuit breaker still has problems in insulation, that is, when there is a transient high pulse voltage in the system, the live end of the insulating pull rod connected to the vacuum bubble end and the phase of the operating mechanism There is an instantaneous high voltage difference between the ground terminals of the connected insulating rods. If the length of the insulating part of the insulating rod is insufficient, this high voltage difference will cause the air in the insulating barrel to be broken down, thereby causing vacuum bubbles to move the terminal. short circuit problem

In order to prevent this problem, it is necessary to increase the length of the insulating part of the insulating tie rod, but this solution is not conducive to the overall size reduction of the circuit breaker, which is contrary to the current development trend

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