Power converter

A power converter, comprising:

• a power conversion circuit configured to connect a first switch with a second switch in series while connecting a third switch with a fourth switch in series;
• separately connecting the first switch with the third switch and the second switch with the fourth switch;
• connecting a second capacitor with two ends of the third switch and the fourth switch;
• connecting a series circuit comprising a first capacitor and a second inductor with a series circuit composed of a third capacitor and a primary winding of a transformer in parallel at the connection point of the first and the second switch and the connection point of the third switch and the fourth switch;
• connecting a first diode, a third inductor and a fourth capacitor in series in a closed manner at one side of a secondary winding of the transformer;
• connecting a second diode, a fourth inductor and the fourth capacitor in series in a closed manner at another side of the secondary winding of the transformer;
• connecting a series circuit comprising an alternating voltage power supply and a first inductor (in parallel) with two ends of the first capacitor;
• connecting a load with two ends of the fourth capacitor;
• and
• a control section comprising a control unit, the control section configured to supply, in order to make a current resulting from mixing a low-frequency component of the alternating voltage power supply with a high-frequency component flow through the power conversion circuit, pulse signals for alternatively opening and closing a first group consisting of the first switch and the fourth switch and a second group consisting of the second switch and the third switch to the first group and the second group based on an input voltage obtained by a unit for detecting a voltage input from the alternating voltage power supply, an output voltage obtained by a unit for detecting a voltage output to the load, a circuital current obtained by a unit for detecting a current flowing through the power conversion circuit and a smoothed voltage obtained by a unit for detecting the voltage of the second capacitor, the control unit further comprising a sine wave generation unit configured to generate a sine wave having the same phase with voltage of the alternating voltage power supply based on the signal of the alternating voltage detected by the alternating voltage detection unit.