Analysis and Design of a Thomson Coil Actuator System for an HVDC Circuit Breaker

In this study, we analyze and design a Thomson coil actuator system (TCAS) that ensures stable operation of a high voltage direct current circuit breaker. High voltage direct current circuit breakers require a high-speed actuator and proper brake system that can absorb the kinetic energy of fast-moving mass to prevent damage and malfunction of the device. However, existing brake systems degrade the responsiveness of TCAS. Therefore, the proposed TCAS is designed to improve the low responsiveness of the actuator, which is caused by braking forces, by applying a series spring brake system and latch type holding system. An equivalent circuit model of TCAS that reflects its electromagnetic and kinetic properties is derived and applied to the design of the TCAS. The validity of the proposed TCAS design and analysis model is verified through prototype experiments. The experimental results show that the proposed TCAS completes a 30 mm stroke opening operation in 5.4 ms at a drive voltage of 300 V, and the analysis results reveal that the error rate for the experimental results is 4.65%.