Parallel type circuit breakers based on tightly coupled air reactor

Abstract

The invention relates to parallel type circuit breakers based on a tightly coupled air reactor, belonging to the field of high-voltage and high-capacity circuit breaker devices. The invention aims at automatic current sharing and current limiting. Parallel operation of the circuit breakers is realized by adopting the tightly coupled air reactor. The current input ends on two arms of the tightly coupled air reactor are positioned at the same side of the reactor, are short connected and are connected into a system by being welded with a wiring board, the current output ends on the two arms are respectively connected with two circuit breakers after being welded with the wiring board, and the other ends of the circuit breakers are short connected and connected with the system, therefore, the whole parallel type circuit breaker devices based on the tightly coupled air reactor are connected into the system in series, and the wiring board at the output end of the tightly coupled air reactor is supported by a post insulator and is fixed on a prefabricated platform. The circuit breakers are connected in parallel by adopting the tightly coupled air reactor, thereby breaking the short-circuit current by times and improving the entire breaking capability.

Description

Parallel circuit breaker based on tightly coupled air-core reactor technical field The invention relates to a parallel circuit breaker based on a tightly coupled air-core reactor, belonging to the field of high-voltage and large-capacity circuit breaker combination devices. Background technique With the rapid development of the power system, the level of short-circuit current increases sharply, and the interrupting capacity of the original switchgear will not meet the requirements; A generator outlet circuit breaker (GCB) is installed, but the short-circuit current at the outlet of large generators is large, and the breaking capacity of domestic GCB products does not meet the requirements. Even if imported products meet the requirements, their price is extremely expensive, which brings obstacles to the protection of generator outlets. The short-circuit current of the power system is also increasing, especially after the short-circuit current of the 500kV substation increa...

AI Technical Summary

Problems solved by technology

However, directly connecting circuit breakers in parallel has the problem of different phases of operation, and still cannot solve the problem of excessive short-circuit current; realizing parallel connection of circuit breakers with a synchronous holding device not only has low synchronization reliability, but also has a high cost, so it has not been promoted so far ; Although the parallel connection method of direct series inductors can ensure a better current sharing effect, the inductance will increase the normal operating impedance, greatly reduce the transmission capacity of the line, and increase the cost of use

Therefore, the reliability of the above parallel scheme is poor and cannot meet the requirements of parallel breaking

Although the Chinese patent 200710052947.7 "Parallel Circuit Breaker" mentions the parallel connection technology of circuit breakers, it is limited to a conceptual design, and its reactor components are limited to iron core reactors, and there are iron cores such as saturation and heat generation during operation. Inherent Disadvantages of Reactors

Chinese patent 200810197118.2 "Hollow coupling reactor" has the design idea of ​​parallel circuit breaker components—coupling reactor, but does not consider heat dissipation in the specific structure, which will inevitably lead to serious consequences in actual operation, so it is not feasible

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