Optimal design of a tubular linear surface-mounted permanent magnet actuator for high voltage breaker

A 15 slots 8 poles tubular linear surface-mounted permanent-magnet motor (15/8 TLSPM) is proposed in this paper which is used as the actuator of high voltage breaker. Teeth design of the TLSPM is discussed and the detent force is analyzed so as to present an efficient method to reduce undesired fluctuations in thrust force. The detent force is divided into two parts, namely cogging force and end effect force. More attention is paid to minimize the end effect force via searching the most suitable width of the end teeth as end effect force accounts for major proportion in the detent force. The model of the 15/8 TLSPM's finite element analysis (FEA) is constructed where the flux distributions and detent force under different teeth types are analyzed. From the simulated characteristics results the optimal design of TLSPM can be obtained.