Vector control of permanent magnet synchronous motors including stator iron loss

The speed control ability of permanent magnet synchronous motor (PM motor) is affected by parameter variation and disturbance torque. In this paper, the robust speed control method of PM motors with the disturbance torque observer is proposed, in which the disturbance torque observer is used for the compensation of parameter variations and disturbance torque. The influence of estimation error of disturbance torque is restrained by time-varying feedback gain. Also, the robust current control system of which distorted current is restrained can be constructed with the disturbance voltage observer that estimate the equivalent disturbance voltage including the effect of parameter variations. This control system considers the influence of stator iron loss that increases with increasing driving frequency in high speed operations, conventional control system usually avoids this effect