Thrust fluctuation analysis and reduction of PMSLM

Servo characteristics of permanent magnet synchronous linear motors (PMSLM) was improved by studying measures to reduce the thrust fluctuation in PMSLM. Thrust ripple, the cogging effect and the edge effect are the main reasons of thrust fluctuation. The thrust fluctuation due to thrust ripple can be reduced by proper current control strategy. The thrust fluctuation can also be greatly reduced by proper selection of magnet shapes and positioning and magnetizing methods. The cogging effect and edge effect, the important reasons of thrust fluctuation, can be greatly reduced by proper design of the primary and secondary structure.