Implementation of Space Vector Switching Technique using a Simplified Approach for a Five Leg Voltage Source Inverter

This paper proposes a simplified approach to implement space vector pulse width modulation (SVPWM) technique for five leg voltage source inverter (VSI) which can drive five-phase machines. SVPWM scheme has greater advantage when it comes to full utilization of DC bus voltage. In this work, the effect of NULL vector is analyzed in detail. A simple technique is introduced in which NULL vector is eliminated which leads to reduced number of switching states. As a result, it is observed that the maximum reduction in the switching losses that can be achieved is approximately 18.52 % which corresponds to the inverter operation at higher modulation indices. In the proposed technique, the switching frequency does not remain constant but swings within a narrow range. Therefore, the magnitude spectrum of voltage without NULL vectors almost remains the same as that of with NULL vectors scenario. A comprehensive analysis of the technique is presented with simulation results in MATLAB/Simulink.