With the development of the global power system and the increasing requirement for operation reliability of power system

more and more utilities have proposed to adopt three-pole mechanical gang operation form for circuit breaker of gas-insulated metal-enclosed switchgear（GIS）so to prevent occurrence of open-phase operation of circuit breaker due to deviation of electrical gang operation. The newly developed 252 kV three-pole gang operated circuit breaker by a certain high voltage company is described in detail. In this scheme

the drive structure of"lever box +drive linkage"is adopted to achieve three pole gang operation and such problems as weak synchronization due to drive error between phases

severe lateral force of linkage plate of main shaft and excessive motion mass of three pole gang operated circuit breaker etc

and related test verification is obtained

which can provide a definite reference for other subsequent three pole gang designs.