Dynamic Adaptive Space Vector PWM for Four Switch Three Phase Inverter Fed Induction Motor with Compensation of DC-Link Voltage Ripple

This paper presents and analyses a new dynamic adaptive space vector PWM algorithm for four- switch three-phase inverters (FSTPI) fed induction motor under DC-link voltage ripple. By using reasonable mathematical transform, Space Vector PWM technique for FSTPI under DC-link voltage imbalance or ripples has been proposed, which is based on the establishment of basic space vectors and modulation technique in similarity with six-switch three-phase inverters. This approach has a very important sense to solve hard problems for FSTPI under DC-link voltage imbalance, for example ensuring the required voltage for under modulation mode and over modulation mode I and 2, extended to six-step mode. The compensated technique also allows reduce the size of DC-link capacitors and the cost of the inverter. Matlab/Simulink is used for the simulation of the proposed SVPWM algorithm under DC-link voltage ripple. This SVPWM approach is also validated experimentally using DSP TMS320LF2407a in FSTPI-IM system. The effectiveness of this adaptive SVPWM method and the output quality of the inverter are verified.