Power factor correction converter and control method thereof
A power factor correction converter and a control method are disclosed. A power factor correction converter includes a power conversion module, a capacitor, a third switch unit, and a fourth switch capacitor. The power conversion module includes a first switch, a second switch, a first switch unit, a second switch unit, and an inductor. The first switch is coupled to a first input terminal. The second switch is coupled to a second input terminal. The first switch is coupled between an output terminal and the first switch. The second switch is coupled between the output terminal and the second switch. The inductor is coupled between the first and the second switch unit. The capacitor is coupled to the output terminal. The third switch unit is coupled between the second input terminal and the capacitor. The fourth switch unit is coupled between the first input terminal and the capacitor.
1. A power factor correction converter, comprising:
a power conversion module having a first input terminal, a second input terminal, and an output terminal, the first input terminal and the second input terminal being electrically coupled to an AC power source, the power conversion module comprising a first switch, a second switch, a first switch unit, a second switch unit, and a power factor correction inductor, the first switch being electrically coupled to the first input terminal, the second switch being electrically coupled to the second input terminal, the first switch unit being electrically coupled to the output terminal and the first switch unit and the first switch being electrically coupled to a first voltage node, the second switch unit being electrically coupled to the output terminal and the second switch unit and the second switch being electrically coupled to a second voltage node, the power factor correction inductor being electrically coupled between the first voltage node and the second voltage node;
an output capacitor electrically coupled to the output terminal for generating a DC output voltage;
a third switch unit electrically coupled between the second input terminal and the output capacitor; and
a fourth switch unit electrically coupled between the first input terminal and the output capacitor.
2. The power factor correction converter of claim 1 , wherein each of the first switch unit, the second switch unit, the third switch unit, and the fourth switch unit comprises a switching device.
3. The power factor correction converter of claim 1 , wherein each of the first switch unit and the second switch unit comprises a diode.
4. The power factor correction converter of claim 1 , wherein each of the third switch unit and the fourth switch unit comprises a slow reverse recovery diode.
5. The power factor correction converter of claim 1 , wherein each of the first switch unit and the second switch unit comprises a fast reverse recovery diode, each of the third switch unit and the fourth switch unit comprises a slow reverse recovery diode, and a reverse recovery time of the third switch unit and the fourth switch unit is more than two times of a reverse recovery time of the first switch unit and the second switch unit.
6. The power factor correction converter of claim 1 , further comprising a sensing unit electrically coupled to the output capacitor in series.
7. The power factor correction converter of claim 1 , further comprising a sensing unit electrically coupled between the first input terminal and the AC power source.
8. The power factor correction converter of claim 1 , wherein the power conversion module further comprises:
a coupled inductor electrically coupled to the power factor correction inductor; and
a signal processing circuit electrically coupled to the coupled inductor to detect a current flowing through the coupled inductor.
9. The power factor correction converter of claim 1 , further comprising a DC/DC converter electrically coupled to the output terminal to adjust the DC output voltage.
10. The power factor correction converter of claim 9 , wherein the DC/DC converter comprises a LLC resonant converter, a LC resonant converter, a boost converter, a buck converter, or a buck-boost converter.
11. The power factor correction converter of claim 1 , further comprising:
a first bypass diode electrically coupled between the first input terminal and the output terminal; and
a second bypass diode electrically coupled between the second input terminal and the output terminal.
12. A power factor correction converter, comprising:
a plurality of power conversion modules, each of the power conversion modules having a first input terminal, a second input terminal, and an output terminal, the first input terminal and the second input terminal being electrically coupled to an AC power source, the first input terminals of the power conversion modules being coupled together, the second input terminals of the power conversion modules being coupled together, the output terminals of the power conversion modules being coupled together, each of the power conversion modules comprising a first switch, a second switch, a first switch unit, and a second switch unit, and a power factor correction inductor, the first switch being electrically coupled to the first input terminal, the second switch being electrically coupled to the second input terminal, the first switch unit being electrically coupled to the output terminal and the first switch unit and the first switch being electrically coupled to a first voltage node, the second switch unit being electrically coupled to the output terminal and the second switch unit and the second switch being electrically coupled to a second voltage node, the power factor correction inductor being electrically coupled between the first voltage node and the second voltage node;
an output capacitor electrically coupled to the output terminals for generating a DC output voltage;
a third switch unit electrically coupled between the second input terminals and the output capacitor; and
a fourth switch unit electrically coupled between the first input terminals and the output capacitor.
13. The power factor correction converter of claim 12 , wherein each of the first switch unit, the second switch unit, the third switch unit, and the fourth switch unit comprises a switching device.
14. The power factor correction converter of claim 12 , wherein each of the first switch unit and the second switch unit comprises a diode.
15. The power factor correction converter of claim 12 , wherein each of the third switch unit and the fourth switch unit comprises a slow reverse recovery diode.
16. The power factor correction converter of claim 12 , wherein each of the first switch unit and the second switch unit comprises a fast reverse recovery diode, each of the third switch unit and the fourth switch unit comprises a slow reverse recovery diode, and a reverse recovery time of the third switch unit and the fourth switch unit is more than two times of a reverse recovery time of the first switch unit and the second switch unit.
17. The power factor correction converter of claim 12 , further comprising:
a DC/DC converter electrically coupled to the output terminal to adjust the DC output voltage.
18. The power factor correction converter of claim 17 , wherein the DC/DC converter comprises a LLC resonant converter, a LC resonant converter, a boost converter, a buck converter, or a buck-boost converter.
19. The power factor correction converter of claim 12 , further comprising:
a first bypass diode electrically coupled between the first input terminal and the output terminal; and
a second bypass diode electrically coupled between the second input terminal and the output terminal.
20. A method for controlling a power factor correction converter, the power factor correction converter having a first input terminal, a second input terminal, and an output terminal, the first input terminal and the second input terminal being electrically coupled to an AC power source, the power factor correction converter comprising a first switch, a second switch, a first switch unit, a second switch unit, a power factor correction inductor, an output capacitor, a third switch unit, and a fourth switch unit, the first switch being electrically coupled to the first input terminal, the second switch being electrically coupled to the second input terminal, the first switch unit being electrically coupled to the output terminal and the first switch unit and the first switch being electrically coupled to a first voltage node, the second switch unit being electrically coupled to the output terminal and the second switch unit and the second switch being electrically coupled to a second voltage node, the power factor correction inductor being electrically coupled between the first voltage node and the second voltage node, the output capacitor being electrically coupled to the output terminal for generating a DC output voltage, the third switch unit being electrically coupled between the second input terminal and the output capacitor, the fourth switch unit being electrically coupled between the first input terminal and the output capacitor, the method comprising:
complementarily turning on the second switch and the second switch unit, turning on the first switch and the third switch unit, and turning off the first switch unit and the fourth switch unit during the positive half cycle of the AC power source to adjust the DC output voltage; and
complementarily turning on the first switch and the first switch unit, turning on the second switch and the fourth switch unit, and turning off the second switch unit and the third switch unit during the negative half cycle of the AC power source to adjust the DC output voltage.
21. The method of claim 20 , wherein the third switch unit is a slow reverse recovery diode, thereby a terminal of the output capacitor is electrically coupled to the second input terminal when the second switch unit is turned off.
22. The method of claim 20 , wherein the fourth switch unit is a slow reverse recovery diode, thereby a terminal of the output capacitor is electrically coupled to the first input terminal when the first switch unit is turned off.
23. The method of claim 20 , further comprising:
providing a first bypass diode, wherein the first bypass diode is configured to be electrically coupled between the first input terminal and the output terminal; and
providing a second bypass diode, wherein the second bypass diode is configured to be electrically coupled between the second input terminal and the output terminal;
wherein the first bypass diode, the second bypass diode, the third switch unit, and the fourth switch unit form a rectifier circuit to charge the output capacitor when an inrush current is generated by the AC power source.