A large capacity circuit breaker

Abstract

The invention discloses a large-capacity circuit breaker. The large-capacity circuit breaker comprises a plurality of movable contact units, a contact supporting mechanism and an operation connecting rod, wherein each movable contact unit comprises a conductive plate, a flexible connector, movable contacts and an arc main contact which are sequentially connected to one another; the contact supporting mechanism comprises a long magnet yoke plate; three connecting racks sleeve the long magnet yoke plate, namely, the three connecting racks are respectively arranged on a left phase rod, a middle phase rod and a right phase rod of the long magnet yoke plate correspondingly in a penetrating manner; an insulating rack is inserted in each connecting rack; the fronts of bottom plates of the insulating racks are tightly pressed on the long magnet yoke plate; the flexible connector of each movable contact unit is correspondingly clamped in the corresponding insulating rack; and the movable contacts of each movable contact unit are strung together through a corresponding short magnet yoke rod. The large-capacity circuit breaker is simple and reliable in structure and high in work efficiency.

Description

technical field [0001] The invention belongs to the technical field of low-voltage power distribution appliances, and relates to a large-capacity circuit breaker. Background technique [0002] With the doubling of demand in the power industry and the continuous improvement of power grid capacity, the short-circuit current has increased exponentially and dozens of times compared to before, resulting in frequent occurrence of short-circuit accidents. This requires a circuit breaker with ultra-high ultimate short-circuit breaking capacity, instantaneous (short-time) withstand current capability, super-large rated operating breaking current, low temperature rise, segmental reliability, miniaturization, and light weight. [0003] The existing circuit breaker (contact system) has the following disadvantages and deficiencies: [0004] 1) The resistance values ​​of the springs, shafts and contact brackets in the contact system are much larger than those of copper and silver parts. ...

AI Technical Summary

Problems solved by technology

[0015] The purpose of the present invention is to provide a large-capacity circuit breaker, which solves the problems in the prior art such as rising body temperature, unsynchronized opening and closing of the three-phase contact system, low electrodynamic induction compensation, low opening and closing speed, and contact failure. The head is not burned at the same time, the electrical life of the contact is short, and the circuit breaker cannot be miniaturized, lightweight, and large-capacity; in addition, it solves the problem that the contact support of the existing frame circuit breaker exists during the movement process, due to its strength Poor, the traction hole is prone to cracks or even breaks, which affects the service life

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