Sensorless Speed Vector Control of a Trapezoidal back-EMF PMSM Machine using Pseudo-Park Transformation for Fan Motor Drives

摘要

This paper uses an extension of Park's transformation to model a permanent magnet non-sinusoidal machine on pseudo-dq axes, achieving with it the speed and torque vector control with a performance equal to those of sinusoidal machines drives. By analogy to the latter, this is accomplished by decomposing the machine current into two components, namely the torque and flux components. In addition to the dq-axes vector control, a sensorless control strategy is implemented using a linear back-EMF observer on pseudo dq-axes cascaded with a rotor position tracking controller. The paper presents an in-depth model derivation, focusing on the use of the pseudo-Park transformation and how to decouple the output of the current controllers, i.e., decoupling of the d-q channel dynamics. Emphasis is given as well to the estimation of the rotor speed and position. Simulation results are used to validate the proposed model and sensorless control strategy.