Power converter with surge voltage suppression

A power converter for converting power received from a power source, and supplying the converted power to a load, comprising:

• a semiconductor switching element;
• a control circuit that controls turning on and off of the semiconductor switching element;
• and
• an LC circuit formed of an inductor and a capacitor, the inductor being connected between the semiconductor switching element and the load, the capacitor being connected between a load side terminal of the inductor and one end of the power source;
• the control circuit providing a control signal for turning the semiconductor switching element into an on-state,
• wherein
• the control signal is configured of a first on-signal and second on-signal,
• an off-state period is provided between the first on-signal and the second on-signal of the control signal, the off-state period being a time practically equivalent to a period of the first on-signal, and
• the period of the first on-signal the off-state period are set to a time practically one-sixth of a resonance cycle of the LC circuit provided between the semiconductor switching element and the load.

A power converter for converting power received from a power source, and supplying the converted power to a load, comprising:

• a semiconductor switching element;
• and
• a control circuit that controls turning on and off of the semiconductor switching element;
• the control circuit providing a control signal for turning the semiconductor switching element into an off-state,
• wherein
• the control signal is configured of a first off-signal and a second off-signal,
• an on-state period is provided between the first off-signal and the second off-signal of the control signal, the on-state period being a time practically equivalent to a period of the first off-signal, and
• the period of the first off-signal and the on-state period provided are set to a time practically one-sixth of a resonance cycle of impedance existing between the semiconductor switching element and the load.

A power converter for converting the power received from a power source, and supplying the converted power to a load, comprising:

• a semiconductor switching element;
• a control circuit that controls turning on and off of the semiconductor switching element;
• and
• an LC circuit formed of an inductor and a capacitor, the inductor being connected between the semiconductor switching element and the load, the capacitor being connected between a load side terminal of the inductor and one end of the power source;
• the control circuit providing a control signal for turning the semiconductor switching element into an off-state,
• wherein
• the control signal is configured of a first off-signal and a second off-signal, an on-state period is provided between the first off-signal and the second off-signal of the control signal, the on-state period being a time practically equivalent to a period of the first off-signal, and the period of the first off-signal and the on-state period are set to a time practically one-sixth of a resonance cycle of the LC circuit provided between the semiconductor switching element and the load.

An apparatus comprising:

• an inductive device;
• a capacitive device coupled to the inductive device;
• a switching device having output terminals coupled to the inductive device and the capacitive device;
• and
• a control device coupled to the switching device, configured to output a sequence of on and off signals to cause a sequence of state changes in the switching device;
• wherein the sequence of on and off signals is configured to cause a sequence of resonance voltage waveforms in the inductive device and capacitive device, caused by the sequence of state changes in the switching device, to combine so as to generate a composite waveform of a predetermined profile;
• wherein the sequence of on and off signals comprises an on signal followed by an off signal of substantially a same duration as the on signal.