Energy recovery circuit and energy recovery method using the same

• US 7,009,823 B2
• Filed: 06/28/2002
• Issued: 03/07/2006
• Est. Priority Date: 06/28/2002
• Status: Expired due to Fees

• Current Assignee: LG Electronics, Inc. (LG Corporation)
• Original Assignee: LG Electronics, Inc. (LG Corporation)
• Inventors: Yoon, Won Sik, Park, Han Woong, Kim, Cheul U, Kang, Feel Soon
• Primary Examiner(s): Sircus, Brian
• Assistant Examiner(s): Demakis, James A.
• Application Number:
  US10/183,382
• Publication Number:
  US 20040001290A1
• Time in Patent Office: 1,348 Days
• Field of Search: 361/18, 361/58, 361/15, 345/60, 345/204, 359/250, 315/169.2, 315/169.3
• US Class Current: 361/15
• CPC Class Codes: G09G 2330/025 Reduction of instantaneous peaks of current
• CPC Class Codes: G09G 3/2965 using inductors for energy recovery

Abstract

An energy recovery circuit wherein an energy stored in an inductor is applied to a panel to reduce a charge time and improve an energy recovery efficiency. In the energy recovery circuit, a switch, a capacitor and an inductor is provided to form a closed loop. A panel capacitor is equivalently provided at the panel. When the switch is turned on, a current component of an energy is charged in the inductor by an energy charged in the capacitor. When the switch is turned off, an inverse voltage is inducted into the inductor and a closed loop is formed by the inductor and the panel capacitor, thereby applying only an inverse voltage of the inductor to the panel capacitor.

Claims

1. An energy recovery circuit for recovering energy from a panel, comprising:

a first switch, a capacitor and an inductor provided to form a first closed loop;

a panel capacitor equivalently provided at the panel;

a sustain voltage source;

a second switch coupled between the sustain voltage source and the panel capacitor, and

wherein when the first switch is turned on, a current component of an energy is charged in the inductor by an energy charged in the capacitor, and

when the first switch is turned off, an inverse voltage is induced into the inductor and a second closed loop is formed by the inductor and the panel capacitor, thereby applying only an inverse voltage of the inductor to the panel capacitor.

2. The energy recovery circuit as claimed in claim 1, wherein the capacitor is charged by energy recovered from the panel capacitor.

3. The energy recovery circuit as claimed in claim 1, further comprising:

a diode, being provided between the inductor and the panel capacitor, for applying a voltage from the inductor to the panel capacitor while shutting off other voltage.

4. The energy recovery circuit as claimed in claim 1, wherein the sustain voltage source for generating a sustain voltage, and

the second switch to be turned on when a voltage from the sustain voltage source is applied to the panel capacitor, the second switch being different than the first switch, the energy recovery circuit further comprising:

a third switch having one terminal connected to the first switch and the capacitor and another terminal connected to a ground; and

a fourth switch connected between the second switch and the ground.

5. The energy recovery circuit as claimed in claim 3, wherein said inverse voltage induced into the inductor has approximately a voltage level of the sustain voltage source.

6. The energy recovery circuit as claimed in claim 4, wherein when the third switch is turned on, the capacitor, the panel capacitor and the third switch form a third closed loop to recover an energy of the panel capacitor into the capacitor.

7. The energy recovery circuit as claimed in claim 3, wherein when the first switch is turned off, the inductor into which said inverse voltage is induced, the panel capacitor and the diode form the second closed loop.

8. The energy recovery circuit as claimed in claim 4, wherein when the first switch is turned off, the inductor into which said inverse voltage is induced, the panel capacitor and the diode form the second closed loop.

9. The energy recovery circuit as claimed in claim 4, wherein when the fourth switch is turned on, the panel capacitor is connected to the ground for its initialization.

13. The energy recovery circuit as claimed in claim 1, wherein the first closed loop is formed from one terminal of the capacitor, via the inductor and the first switch, into another terminal of the capacitor.

14. The energy recovery circuit as claimed in claim 1, wherein when the first switch is on, current is charged in the inductor due to electric charges discharged from the capacitor.

10. An energy recovery method using an energy recovery circuit including a panel capacitor equivalently provided at a panel, comprising the steps of:

charging a current component of an energy into an inductor by utilizing an energy charged in the capacitor;

deriving an inverse voltage into the inductor;

forming a closed loop by the inductor and the panel capacitor to apply only an inverse voltage of the inductor to the panel capacitor; and

connecting the panel capacitor to ground to initialize the panel capacitor.

11. The energy recovery method as claimed in claim 10, further comprising the step of:

applying a voltage from a sustain voltage source to the panel capacitor.

12. The energy recovery method as claimed in claim 10, further comprising the step of:

recovering an energy charged in the panel capacitor into the capacitor.

15. An energy recovery circuit for a plasma display panel, comprising:

a first switch between nodes of a capacitor and an inductor;

a sustain voltage source; and

a second switch between the sustain voltage source and a panel capacitance, wherein when the first switch is on, a closed loop is formed from one terminal of the capacitor, via the inductor and the first switch, into another terminal of the capacitor to store energy into the inductor based on charges of the capacitor, and

when the first switch is off, an inverse voltage is induced at the inductor and the stored energy is provided to the panel capacitance.

16. The energy recovery circuit as claimed in claim 15, wherein when the first switch is off, another closed loop is formed by the inductor and the panel capacitance.

17. The energy recovery circuit as claimed in claim 16, wherein when the first switch is off, only the inverse voltage of the inductor is applied to the panel capacitance.

18. The energy recovery circuit as claimed in claim 15, wherein the capacitor is charged by energy from the panel capacitance.

19. The energy recovery circuit as claimed in claim 15, further comprising:

a diode between the inductor and the panel capacitance to apply a voltage from the inductor to the panel capacitance while shutting off other voltages.

20. The energy recovery circuit as claimed in claim 15, wherein the sustain voltage source to generate a sustain voltage,

the second switch to be turned on when a voltage from the sustain voltage source is applied to the panel capacitance, the second switch being different than the first switch, the energy recovery circuit further comprising:

a third switch having one terminal coupled to the first switch and the capacitor and another terminal coupled to GROUND; and

a fourth switch coupled between the second switch and GROUND.

21. The energy recovery circuit as claimed in claim 20, wherein when the first switch is off, only the inverse voltage of the inductor is applied to the panel capacitance.

22. The energy recovery circuit as claimed in claim 21, wherein said inverse voltage is approximately a voltage level of the sustain voltage source.

23. The energy recovery circuit as claimed in claim 20, wherein when the third switch is turned on, the capacitor, the panel capacitance and the third switch form another closed loop to recover energy of the panel capacitance into the capacitor.

24. The energy recovery circuit as claimed in claim 20, wherein when the first switch is turned off, the inductor, the panel capacitance and the diode form another closed loop.

25. The energy recovery circuit as claimed in claim 20, wherein when the fourth switch is turned on, the panel capacitance is coupled to GROUND to initialize the panel capacitance.

26. An energy recovery method of a plasma display panel comprising:

turning on a first switch to store energy from a capacitor into an inductor;

turning off the first switch to apply current to a panel capacitance based on an inverse voltage induced at the inductor; and

turning on a second switch to apply a voltage from a sustain voltage source to the panel capacitance.

27. The energy recovery method of claim 26, wherein turning on the first switch forms a closed loop from one terminal of the capacitor, via the inductor and the first switch, into another terminal of the capacitor.

28. The energy recovery method of claim 27, wherein turning off the switch forms another closed loop that includes the inductor and the panel capacitance.

29. The energy recovery method as claimed in claim 28, wherein the second switch is provided between the sustain voltage source and the panel capacitance, the second switch being different than the first switch.

30. The energy recovery method as claimed in claim 28, further comprising:

recovering energy in the panel capacitance into the capacitor.

31. The energy recovery method as claimed in claim 28, further comprising:

coupling the panel capacitance to GROUND to initialize the panel capacitance.

32. An energy recovery circuit comprising:

a first switch, a second switch, a third switch and a fourth switch that operate to charge and discharge a panel capacitance;

an inductor;

a capacitor; and

a sustain voltage source to provide a sustain voltage, wherein the second switch is provided between the sustain voltage source and the panel capacitance and is turned on for applying the sustain voltage source to the panel capacitance, the third switch having one terminal coupled to the first switch and the capacitor and another terminal coupled to a prescribed potential, and the fourth switch is coupled between the second switch and the prescribed potential.

33. The energy recovery circuit of claim 32, wherein when the first switch is turned on, a current component of energy is charged in the inductor based on energy in the capacitor.

34. The energy recovery circuit of claim 32, when the first switch is turned off, an inverse voltage is induced into the inductor and a closed loop is formed by the inductor and the panel capacitance, thereby applying an inverse voltage of the inductor to the panel capacitance.

35. The energy recovery circuit of claim 34, wherein said inverse voltage is approximately a voltage level of the sustain voltage source.

36. The energy recovery circuit of claim 32, further comprising:

a diode provided between the inductor and the panel capacitance to apply a voltage from the inductor to the panel capacitance while shutting off other voltages.

37. The energy recovery circuit of claim 36, wherein when the first switch is turned off, the inductor, the panel capacitance and the diode form a closed loop.

38. The energy recovery circuit of claim 32, wherein when the third switch is turned on, the capacitor, the panel capacitance and the third switch form a closed loop to recover energy of the panel capacitance into the capacitor.

39. The energy recovery circuit of claim 32, wherein when the first switch is turned off, the inductor, the panel capacitance and the diode form a closed loop.

40. The energy recovery circuit of claim 32, wherein when the fourth switch is turned on, the panel capacitance is coupled to GROUND for initialization.

41. The energy recovery circuit of claim 32, wherein the fourth switch is directly coupled to the prescribed potential.

42. The energy recovery circuit of claim 32, wherein the another terminal of the third switch is directly coupled to the prescribed potential.