Novel discrete-time predictive current regulators for parallel resonant DC link inverter

Abstract

This paper presents two kinds of novel discrete-time current control methods for induction motor drives that are fed by Parallel Resonant DC Link Inverter (PRDCLI). They are based on using modified fixed band hysteresis control and optimal control. Since zero bus voltage intervals are generated on the DC link of PRDCLI, the counter electromotive force (EMF) of an induction motor and the average value of DC link voltage can be estimated. Based on the previously estimated values, the proposed current regulators predict phase currents of one and/or two-step ahead resonant cycle. The computer simulation result shows that the proposed control schemes offer not only the advantage of zero-voltage-switching (ZVS) resonant inverters but also a reduced total harmonic distortion (THD) compared with conventional current regulators.