Research on force and direct thrust control for a permanent magnet synchronous linear motor

Magnetic field of a permanent magnet synchronous linear motor (PMSLM) has been analyzed at first. Then thrust force has been taken into account completely in the paper. Experiment results are coincident with calculation of finite element method. It is obviously observed undulate force, which has effect on force control in drive system. Direct torque control has prominence characteristic of fast response. Simulation analysis for the prototype shows that the control schema can be applied in linear motor driving and the undulate force can be controlled effectively by suitable strategy even complex magnetic field distribution and particular end-effect.