Controlled switching for a group of induction motors

One of the important issues of modern vacuum circuit breakers application is switching a group of induction motors. When switching from inverter-based power supply to direct power supply from the network, over-voltages and inrush currents having an adverse effect on power equipment are possible. This paper suggests a solution using a controlled vacuum circuit breaker. Controlled vacuum circuit breaker helps to reduce over-voltages and inrush currents. Implementation of both controlled switching and phase synchronism for inverter and network voltage decrease over-voltages by 1.2 times of the rated voltage, while inrush torques are eliminated.