Control strategy for single-phase Z-source inverter

The control strategy for single-phase Z-source inverter, which consisted of Z-source network voltage feedback, ac-side instantaneous feedback and voltage ripple feed-forward loop, was presented. Due to the non-minimum-phase effect of Z-source network, an ac-side instantaneous controller was incorporated based on the Z-source network voltage feedback loop to guarantee fast dynamic response. The Z-source network has voltage ripple during operating with the heavy load, which decreases the performance of the output voltage. The proposed voltage ripple feed-forward controller could modify the modulation index, thus the effects were prevented from propagating into the ac-side and hence the quality of the output ac voltage waveform was improved. Both computer simulation and experimental results verify the effectiveness of the proposed strategy.