Abstract: A high frequency current-fed inverter of the series/parallel compensated type is started directly with the main thyristors of the inverter by charging the series capacitor through the input inductor of the DC supply during a first time interval with one pole, by discharging the same during a second time interval with the other pole, then passing to free-running operation at an initial frequency from which load operation can begin. The first and second time intervals are established while a constant DC voltage is being applied so that commutation of the outgoing thyristor is insured. DC voltage regulation is eliminated as soon as the free-running operation has been initiated.