Selection method of controller gains for position sensorless control of IPMSM drives

Rotor position and speed in sensorless control based on back-electromotive force (back-EMF) estimation can be estimated from back-EMF estimator and rotor position estimator in an interior permanent magnet synchronous motor (IPMSM). Even if the rotor position and speed are correctly estimated by these estimators in the steady state, the performance of estimators in the transient state may be degraded by the gain design of estimators. This paper describes the design method of estimators and current controller to ensure stable sensorless control of IPMSM not only in the steady state but also in the transient state such as for torque or speed variation. The performance of our proposed method is verified through a simulation and experimental results.