Sensorless Direct Torque and Flux Controlled IPM Synchronous Machine Fed by Matrix Converter Over a Wide Speed Range

This paper proposes a new sensorless direct torque and flux controlled interior permanent magnet synchronous machine drive fed by a matrix converter. Closed-loop control of both torque and stator flux is achieved by using two PI controllers. The input and output voltage vectors are modulated with the indirect space vector modulation technique. Additionally, unity power factor on the power supply side of matrix converter is achieved through closed-loop compensation of the input displacement angle created by the input filter of matrix converter. The adaptive observer used for joint stator flux and rotor speed estimation is enhanced by HF signal injection scheme for stable operation at low speed including standstill. The stator resistance variation is compensated with the current estimation error. The operating range of the drive is extended into high speed region by incorporating field weakening. The sensorless drive exhibits high dynamic and steady-state performances over a wide speed range. The implementation of digital control system for the proposed matrix converter drive is described in this paper. Extensive experimental results confirming the effectiveness of the proposed method are also included.