Resonant inverter

A resonant inverter comprising:

• an input capacitor and an inverter which are connected to a DC voltage source;
• a snubber circuit formed by a series circuit of a regeneration resistor and a snubber capacitor, and connected in parallel to each leg of the inverter;
• a clamp diode connected between a drain of a switching element of the inverter and a connection point between the regeneration resistor and the snubber capacitor of the snubber circuit;
• a transformer having a primary winding connected to an AC end of the inverter;
• a resonant coil, a resonant capacitor, and a current sensor connected to a secondary winding of the transformer;
• and
• a control unit for controlling the inverter, wherein
• on the basis of current detected by the current sensor, the control unit controls the switching element of the inverter so as to perform zero voltage switching at a time of turning-on, at a frequency at which a load including the resonant coil and the resonant capacitor becomes capacitive, and performs power regeneration of energy stored in the snubber capacitor to the DC voltage source.