Comparative study of harmonic performance of different modulation techniques for Z-Source inverter

Harmonic currents associated with inverter systems are minimized by means of modulation techniques to ensure power quality. In this paper, an analytic study of harmonic performance of six different modulation techniques for Z-Source inverters is presented. The harmonic spectrum of each modulation technique is estimated using double Fourier series approach. The analytical approach is adopted to exclude the common errors caused by practical conditions from simulation or experimental setups, and to present a fair comparison between the different modulation techniques. A collective evaluation of the modulation techniques using weighted total harmonic distortion is presented; taking into account the impact of the applied voltage gain on the harmonic performance.