Three-Phase Motor Control using Modified Reference Wave

摘要

This paper describes the implementation of a modified reference wave using discontinuous pulse width modulation (DPWM-S2) technique. DPWM-S2 [1] command technique is a high performance computational control method, having as a main advantage the reduction of the number of commutations of the power transistors within the three-phase inverter, as compared to other modulation techniques, e.g. Sinusoidal Pulse Width Modulation (SPWM) [2], Space Vector Modulation (SVM) [3], etc. The number of commutations is reduced as, considering equations (1) for two intervals of time (out of six), some transistors are in continuous conduction, and power losses in commutation should be in theory by 1/3 smaller if SPWM or SVM techniques were used. With a reduced number of commutations, power losses on the transistors are decreasing, caloric power is decreasing too and, as a result, smaller heat-sinks are needed on the same transistors.