Three-dimensional finite element analysis of electromagnetic vacuum circuit breaker including a magnetic spring

This paper presents a design of a new highspeed electromagnetic repulsion mechanism for a high-voltage vacuum circuit breaker. This mechanism is based on a Coil-Coil Electromagnetic Repulsion driving and a Permanent Magnet Spring. The latter is used instead of the conventional disk spring due to its more suitable force characteristics for the vacuum interrupter. In this work, we have developed an electromagnetic analysis coupled with motion, which considers the relation of the movement between the plurality of the actuators and the contact of the interrupter connected with a mechanical linkage. Comparing the results from 2D Finite Element Method (FEM) with those from 3D FEM, we understand that 2D FEM is not suitable because of ignoring the magnetic flux distribution inside the yoke of electromagnetic actuator