Abstract: This invention generally relates to voltage balancing among series-connected power switching devices comprising one or more insulated gate bipolar transistor (IGBT), and more particularly to a method controlling sharing of voltage among series-connected power switching devices, wherein at least one said device is an insulated gate bipolar transistor (IGBT), the method comprising: controlling the IGBT dependent on a reference signal and collector or emitter voltage of the IGBT such that during an off period of said IGBT said reference signal limits an absolute value of collector-emitter voltage of said IGBT to be within a range; and control to temporarily change during said limiting said reference signal from an initial value to a temporary clamp value to reduce said range, said change when each of said devices is in a substantially non-conducting state.