Power conversion circuit and power conversion apparatus with same

A power conversion apparatus comprising:

• M power conversion circuits, each power conversion circuit comprising:
• a first terminal including a first positive electrode and a first negative electrode;
• a second terminal including a second positive electrode and a second negative electrode, wherein the second negative electrode is electrically connected with the first negative electrode;
• a first switching conversion unit comprising a first switch and a third switch, which are electrically connected with each other in series, wherein a second terminal of the first switch is electrically connected with the first positive electrode, a first terminal of the third switch is electrically connected with the first negative electrode;
• a second switching conversion unit, wherein a first terminal of the first switch is electrically connected with a first terminal of the second switching conversion unit, a second terminal of the second switching conversion unit is electrically connected with the first negative electrode, and a third terminal of the second switching conversion unit is electrically connected with the second positive electrode;
• a flying capacitor;
• and a magnetic element comprising a first winding and a second winding, wherein the first winding and the second winding interact with each other to result in an electromagnetic coupling effect, a first terminal of the first winding is electrically connected with a second terminal of the third switch, a second terminal of the first winding is electrically connected with the second positive electrode, and the second winding and the flying capacitor are serially connected between the first terminal of the first switch and the first terminal of the first windings;
• wherein a turn ratio between the second winding and the first winding is N:1, and N is a positive value;
• wherein the first switch and the third switch are periodically operated at a switching cycle, and the switching cycle has a duty cycle;
• and wherein the switching cycle comprises a first working period and a second working period, wherein an electrode of a voltage of the flying capacitor is the same as an electrode of a voltage of the second winding during the first working period, and the electrode of the voltage of the flying capacitor is opposite to the electrode of the voltage of the second winding during the second working period.