Development of Electromagnetically Actuated Vacuum Circuit Breaker for 72kV Rated Switchgear

Abstract

A new electromagnetically actuated vacuum circuit breaker (VCB) has been developed for a 72 kV rated switchgear. Each phase of this VCB has a plurality of compact electromagnetic actuators linked mechanically providing the required driving energy. The mechanical linkage working as a lever magnifies an actuator stroke to the required stroke of a 72 kV rated vacuum interrupter. An electromagnetic analysis coupled with motion, which considers the mechanical linkage of the plural actuators, has been developed for designing the driving behavior of this VCB. Using this analytical method and a quality engineering method known as the Taguchi method, we have clarified effective parameters to reduce the time difference of the driving behavior for tolerance specifications. Moreover, analyzing the oscillatory behavior closing the contacts, a structure of this VCB has been designed to reduce the bounce duration. The developed new VCB has been confirmed that a time difference is short enough and bounce duration is reduced. This VCB is highly reliable against variations in manufacturing and environment.

Development of Mechanical CBM System for Electromagnetically Actuated Vacuum Circuit Breaker

“…We have already completed the commercialization of 7.2 kV-84 kV C-GIS [5][6][7]. We have already completed the commercialization of 7.2 kV-84 kV C-GIS [5][6][7].…”

“…For the first time in the world, this CBM system was mounted on 72 kV dry air insulating C-GIS released in February, 2006. We have already completed the commercialization of 7.2 kV-84 kV C-GIS [5][6][7].…”

“…4 corresponds to the state of Fig. (6) where W is the state parameter, and it is the contact erosion here. As described in the previous section, after the point B, the insulating rod, the movable contact, and the armature move together, and hence the mass of these moving parts increases discontinuously at B.…”

“…In this paper, as an example, the estimation result of the contact erosion is presented, which cannot be easily monitored only by placing displacement sensor because the contact is packed in vacuum valve. (6) where W is the state parameter, and it is the contact erosion here. α, β, .…”

“…In this way, it is not necessary to arrange additional sensors outside the system. (6). Figure 8 shows the schematic illustration of the brief structure of the CBM controller mounted cubic type gas insulated switchgear (C-GIS) prepared by our group.…”