A Motor-Drive-Based Operating Mechanism for High-Voltage Circuit Breaker

In order to improve the operation flexibility and reliability of high-voltage circuit breakers (HVCBs) and to realize the full control capability during the opening and closing operations, a new type of motor-drive operating mechanism is investigated in this paper. In this operating mechanism, the travel of the moving contact of HVCB is precisely controlled by controlling the motion of the permanent-magnet synchronous motor (PMSM). A simulation model of the motor control system is built in MATLAB/Simulink and the control algorithm of the PMSM is then introduced. Based on the control theory and simulations, an experimental system with a 126-kV HVCB and a 30-kW PMSM is established to test the motor-drive operating mechanism. The experimental system is an all-digital position servo system with a vector-control algorithm built in a digital signal processor controller. The simulation results and the operating curves from the experimental system show that the proposed motor-drive operating mechanism can fulfill the requirements of HVCB operations and the desired precise travel control of the moving contact of HVCB. This operating mechanism can also enable the intelligent operations of HVCB to meet future requirements of the modern electric power grid.