A novel sensorless direct torque control for matrix converter-fed IPM synchronous machine

A new sensorless direct torque control scheme for matrix converter-fed interior permanent magnet synchronous machine is investigated in this paper. Comparing to the classical DTC, the proposed scheme features in low ripples in torque and flux, fixed switching frequency and unity input power factor. Moreover, it significantly reduces the harmonics in the input current even with a small input filter. An adaptive observer is used for the joint estimation of stator flux and rotor speed. The sensorless DTC drive is capable of exhibiting high dynamic and steady-state performance. Experimental results confirm the effectiveness of the proposed method.