Patent ID: 8836311

Claim:
A power converter including a plurality of switching circuits connected in series, each of the switching circuits comprising: a non-latching type switching element that has two main terminals and a control terminal; a voltage detector that detects a voltage of an emitter of the non-latching type switching element; a first voltage amplifier that amplifies the voltage of the emitter detected by the voltage detector; a control current source that transmits a control signal into the control terminal according to an output of the first voltage amplifier; a delay device that delays a turn-off timing of transmitting the control signal for a predetermined delay time to synchronize one of the switching circuits with another switching circuit connected in series; a second voltage amplifier that amplifies an output of the delay device; a gate resistor connected to an output side of the second voltage amplifier, wherein the control terminal is connected to an output side of the control current source and is connected to the gate resistor on a side opposite to that of the second voltage amplifier, the plurality of switching circuits include: a first switching circuit having a first non-latching type switching element of a first storage time, and a second switching circuit having a second non-latching type switch element of a second storage time that is longer than the first storage time, and for the first non-latching type switching element, a delay-amount setting signal is set higher than that of the second non-latching type switching element to increase the delay amount of its delay device to make the turn-off timing of the first non-latching type switching element coincident with a turn-off timing of the second non-latching type switching element, so that the first non-latching type switching element has a same amount of loss as the second non-latching type switching element.