Ten Years' Experience in Axial Magnetic Field-Type Vacuum Interrupters

About ten years ago, an axial magnetic field electrode was developed for vacuum circuit breakers. Since then, through various improvements in its structure, this electrode has been refined for practical application in vacuum circuit breaker interrupters. The application has successfully covered not only medium-voltage circuit breakers, but also high-voltage (84kV), dc current and large-current circuit breakers. In this paper, our ten years' experience in this area are described.