Sensorless torque control of PMSMs for railway traction applications

This work presents a sensorless torque control of permanent magnet synchronous machines (PMSM) in railway traction applications based on the flux estimation. In order to improve the algorithm performance in a wide speed range, some compensation loops are included. Special techniques for standstill and flying start are also proposed. The sensorless control strategy is validated in a railway simulation platform for a 120kW surface mounted PMSM tramway motor prototype.