sentences:  The current-fed inverter is different from the voltage-fed system in that it utilizes a variable DC input followed by a large inductor at the input to the inverter bridge.The power circuit features a parallel resonant circuit and can have operating frequencies typically from 1 kHz to 1 MHz.As with the voltage-fed system, SCRs are typically used up to 10 kHz with IGBTs and MOSFETs being used at the higher frequencies.