A New Method for Phase-Shift Control and Harmonics Reduction in H-Bridge Z-Source Inverter

Phase-shift control is a common approach to voltage control of traditional H-bridge inverters, but this method has not been used to voltage control of H-bridge Z-source inverter (ZSI) so far. This paper proposes a new phase-shift control method for H-bridge ZSI, which its main difference with phase-shift control of traditional H-bridge inverters is existence of four shoot-through states (short circuit of the H-bridge) in each switching cycle. One of the advantages of proposed method is simultaneous elimination of several harmonics by choosing the appropriate switching angles. Also, with using this phase-shift control method, the amplitudes of low order harmonics for many values of switching angles are less than the amplitudes of low order harmonics in traditional H-bridge VSI. A detailed description of suggested method and comparison with the traditional method are presented in this paper. Simulation results are given to demonstrate the new features of the proposed method.

کلیدواژه ها:

H-bridge Z-source inverter (ZSI) ، phase-shift control ، harmonics elimination ، total harmonic distortion (THD) ، distortion factor (DF)