Implementation and Critical Investigation on Modulation Schemes of Three Phase Impedance Source Inverter

Abstract: new control circuits and algorithms are frequently proposed to control theimpedance (z) source inverter in efficient way with added benefits. as a result, severalmodified control techniques have been proposed in recent years. although these techniques are clearly superior to the simple boost control method which was initially proposed alongwith the z-source inverter (zsi), little or conflicting data is available about their merits relating to each other. in this paper, it is shown how the shoot-through periods are insertedin the switching waveforms of the power switches and the performances of them areanalyzed based on the operation of zsi. simple boost control, maximum boost control,constant boost control and space vector modulation based control methods given in the literature has been illustrated with their control characteristics. a critical investigation onripples of the impedance source elements, output voltage controllability, output harmonic profile, transient response of the voltage across the impedance source capacitor and voltage stress ratio etc has been presented with the simulation results. the simulation results are experimentally verified in the laboratory with digital signal processors (dsp). dsp codingfor the above all control techniques has been generated by interfacing matlab/simulinkwith dsp c6000 tool box and signal processing block set.