Parameter compensation of permanent magnet synchronous machines through airgap power feedback

Torque and speed controlled permanent magnet synchronous motor (PMSM) drives suffer from parameter sensitivity effects. These effects are dominant in the torque controlled PMSM drives and are also noticed in torque limited speed controlled PMSM drives. A parameter compensation scheme using airgap power feedback control is proposed in this paper. The fact that the airgap power is easy to predict and to measure and is accurately reflective of the effects of stator resistance, q axis inductance and rotor flux linkage changes: is the reason to use this signal for parameter compensation. The proposed scheme is incorporated in the dynamic model of the PMSM drive and verified for both the torque and speed controlled modes of operation. Simulation results demonstrate the validity of the proposed technique