A Family of High Step-Up Coupled-Inductor Impedance-Source Inverters With Reduced Switching Spikes

By using coupled inductors, impedance-source inverters can greatly increase their voltage step-up abilities at the expense of high voltage spikes at their dc-links due to leakage inductances. These voltage spikes can then cause damages and greater power losses. Therefore, to better clamp their dc-link voltages, various absorbing circuits have been proposed in this letter for forming a unique family of impedance-source inverters with even higher gains. The abilities of these inverters in clamping their dc-link voltages have been verified by experimental results presented at the end of the letter.