An optimal control for saturated interior permanent magnet linear synchronous motors incorporating field weakening

In this paper, the maximum thrust force per ampere (MTPA) strategy for saturated permanent magnet linear synchronous motors over the entire field weakening region is presented. In other words, influence of magnetic saturation on the MTPA and field weakening strategies as well as motor-inverter limitations is considered. Using the modified MTPA strategy leads to minimized copper losses, and so maximum capacity of motor is utilized. The proposed scheme incorporates all optimal strategies and operates the drive within the voltage and current limits of the motor/inverter. Simulation results for a prototype interior permanent magnet linear synchronous motor demonstrate that the MTPA and field weakening strategies can be successfully implemented for vector controlled saturated permanent magnet linear synchronous motor drives.