Dodecagonal Voltage Space Vector Based PWM Techniques for Switching Loss Reduction in a Dual Inverter Fed Induction Motor Drive

摘要

The dodecagonal space vector generation scheme eliminates the most dominant lower order harmonics fifth and seventh for the entire modulation range, thereby improving the quality of the output waveform and eliminates the sixth harmonic torque pulsations. By considering this advantage, a group of dodecagonal space vector pulsewidth modulation (PWM) techniques is proposed in this article. These techniques improve the harmonic profile of the output waveform further at higher modulation indices compared to conventional dodecagonal space vector PWM. In this article, a generalized closed-form expression for harmonic distortion of various dodecagonal space vector PWM schemes is derived and the analytical results are compared. The proposed PWM techniques are simulated in MATLAB/Simulink environment and validated experimentally on a laboratory prototype. Also, a detailed switching loss analysis for various dodecagonal space vector PWM schemes are obtained and it is shown that the proposed PWM techniques yield lower inverter switching power losses than the conventional scheme throughout the power factor range.