Electric power converting apparatus and induction heating apparatus

A power converter comprising:

• a converter circuit that transforms an input power-supply voltage to a transformed output voltage, the converter circuit including a switch that is switched by a converter gate signal;
• a capacitor smoothing the output voltage output by the converter circuit;
• an inverter circuit that converts a direct-current voltage smoothed by the capacitor into an alternating-current voltage and supplies electric power to a load;
• a current sensor that detects current that is output by the capacitor and is input directly to the inverter circuit without passing through any other component;
• a frequency detector that detects a frequency of a frequency component having a maximum amplitude among frequency components of the current flowing from the capacitor to the inverter circuit, based on a detection result of the current sensor;
• a phase detector that detects a phase of the frequency component having the maximum amplitude among the frequency components of the current flowing from the capacitor to the inverter circuit, and detects a time when each amplitude of the frequency component having the maximum amplitude is zero, based on the detection result of the current sensor;
• a carrier oscillator that generates a pulse width modulation carrier signal;
• a carrier signal controller that controls frequency and phase of the pulse width modulation carrier signal generated by the carrier oscillator, and causes the carrier oscillator to generate a corrected pulse width modulation carrier signal by controlling the frequency and the phase of the pulse width modulation carrier signal generated by the carrier oscillator, based on a detection result of the frequency detector and a detection result of the phase detector, the corrected carrier signal having a frequency that matches the frequency detected by the frequency detector and a rise time synchronized to the time detected by the phase detector;
• and
• a gate drive circuit that generates the converter gate signal based on the corrected phase-modulated carrier signal, and inputs the converter gate signal to the switch of the converter circuit to control switching of the switch of the converter circuit,
• wherein the convertor circuit transforms the input power supply voltage to the transformed output voltage due to the convertor gate signal switching of the switch of the converter circuit.