Comparison of optimized PWM techniques for overmodulation region of two-level inverters

Four optimized PWM algorithms for the overmodulation region are compared in the paper. The optimization is done to minimize the loss-factor, which indicates the harmonic losses of the AC machine. The loss-factors are computed for different pulse ratios as the function of the modulation index. It is shown in the paper that, which technique has the optimal performance in the lower part of overmodulation as the function of the modulation index and the pulse ratio. The calculated results are verified by laboratory tests.