An Improved Multilevel SVPWM and Its Generalized Algorithm

The modulation is the key technique for multilevel inverter, an improved line voltage modulation strategy is proposed, which is based on the nonorthogonal KL coordinates SVPWM and makes some further comprehensive analysis on the original conclusions. The advantage of the strategy is that it has clearer physical meaning and more simple form. One improved three phases balance modulation algorithm for the single phase is got by the proper arrangement of output vectors taking advantage of the basic circuit theory; and then the generalized modulation strategy is deduced, which is suitable for three phases unbalance situation by the consideration of pulse area equal principle. This proposed modulation algorithm has simple format and clear physical concept, in addition, it's easy for the digital implementation. The digital simulations and experiments are presented to verify the conclusions.