Comparison of FOC and DTC methods for a Matrix Converter-fed permanent magnet synchronous motor

Abstract

This paper presents a comparison between Field Oriented Control and Direct Torque Control methods of a Matrix Converter-fed (MC) Permanent Magnet Synchronous Motor (PMSM). MC is becoming widely used because of the unity power factor and the lack of energy storage element. FOC method calculates the duty of MC states with use of geometric relations between voltage and current vectors. DTC method, on the other hand, is based on controlling the length and angle of a stator flux linkage vector with MC states chosen from a Switching Table. Simulation research of control algorithms was performed in MATLAB/Simulink 2013b. Authors compared the quality of moment regulation in both methods, including the electromagnetic torque rise time and torque variance. Moreover, influence of a control algorithm on the power grid current was researched in frequency domain by FFT and THD. DTC method for MC proved to be faster in torque control. FOC method, however, has visibly lower torque ripples and lower THD. Both methods performed well in a torque regulation of a MC fed motor.