Electronic Blast with Remote Capacitor Placement

• US 20080012505A1
• Filed: 11/03/2005
• Published: 01/17/2008
• Est. Priority Date: 11/04/2004
• Status: Active Grant

• Current Assignee: Koninklijke Philips Electronics N.V. (Koninklijke Philips N.V.)
• Original Assignee: Koninklijke Philips Electronics N.V. (Koninklijke Philips N.V.)
• Inventors: Perkins, Seymour, Lord, Jeffrey, Muthu, Subramanian, Clauberg, Bernd
• Granted Patent: US 7,656,670 B2
• Time in Patent Office: Days
• US Class Current: 315/287
• CPC Class Codes: H05B 41/245 for a plurality of lamps
• CPC Class Codes: H05B 41/28 using static converters
• CPC Class Codes: H05B 41/282 with semiconductor devices H05B41/2806, H05B41/288, H05B41/295 take precedence
• CPC Class Codes: Y02B 20/00 Energy efficient lighting technologies, e.g. halogen lamps or gas discharge lamps

Abstract

An electronic ballast with remote capacitor placement includes a first housing (34); a second housing (36); an AC/DC converter (22); a DC bus (24) operably connected to the AC/DC converter (22); a lamp driver (26) operably connected to the DC bus (24); and a storage capacitor (32) connected to the DC bus (24) with capacitor wires (30). The AC/DC converter (22), the DC bus (24), and the lamp driver (26) are disposed in the first housing (34); the storage capacitor (32) is disposed in the second housing (36); and the first housing (34) is thermally isolated and physically separated from the second housing (36).

Claims

1. An electronic ballast comprising:

a first housing 34;

a second housing 36;

an AC/DC converter 22;

a DC bus 24 operably connected to the AC/DC converter 22;

a lamp driver 26 operably connected to the DC bus 24; and

a storage capacitor 32 operably connected to the DC bus 24 with capacitor wires 30;

wherein the AC/DC converter 22, the DC bus 24, and the lamp driver 26 are disposed in the first housing 34;

the storage capacitor 32 is disposed in the second housing 36; and

the first housing 34 is thermally isolated and physically separated from the second housing 36.

2. The electronic ballast of claim 1 further comprising a filter 28 electrically connected between the DC bus 24 and the capacitor wires 30, the filter 28 being disposed at the first housing 34.

3. The electronic ballast of claim 2 wherein the filter 28 comprises:

a filter capacitor 38;

a differential mode EMI coil 40; and

a common mode EMI coil 42, the common mode EMI coil 42 having a first EMI coil 44 magnetically coupled to a second EMI coil 46;

wherein the filter capacitor 38 is connected in parallel across the DC bus 24;

the differential mode EMI coil 40 and the first EMI coil 44 are connected in series between a first side of the DC bus 24 and a first conductor of the capacitor wires 30; and

the second EMI coil 46 is connected in series between a second side of the DC bus 24 and a second conductor of the capacitor wires 30.

4. The electronic ballast of claim 1 wherein the storage capacitor 32 comprises a plurality of capacitors.

5. The electronic ballast of claim 1 wherein the capacitor wires 30 are a shielded conductor pair with a shield 48 electrically connected to common.

6. The electronic ballast of claim 1 wherein the second housing 36 is a grounded metal housing.

7. The electronic ballast of claim 1 further comprising a space 60 formed between the first housing 34 and the second housing 36.

8. The electronic ballast of claim 1 further comprising a third housing 62 disposed between the first housing 34 and the second housing 36.

9. The electronic ballast of claim 1 wherein the first housing 34 is selected from the group consisting of a metal housing and a plastic housing.

10. The electronic ballast of claim 1 wherein the second housing 36 is selected from the group consisting of a metal housing and a plastic housing.

11. An electronic ballast system comprising:

first means for housing an AC/DC converter, a DC bus, and a lamp driver;

second means for housing a storage capacitor; and

means for electrically connecting the DC bus and the storage capacitor;

wherein the first housing means is thermally isolated and physically separated from the second housing means.

12. The system of claim 11 further comprising means for filtering high frequency current from the connecting means.

13. The system of claim 11 further comprising means for shielding the connecting means.

14. An electronic ballast comprising:

a first housing 34;

a second housing 36;

an AC/DC converter 22, the AC/DC converter 22 being operably connected to a mains input 16;

a DC bus 24 operably connected to the AC/DC converter 22;

a lamp driver 26 operably connected to the DC bus 24, the lamp driver 26 being operably connected to a lamp output 18;

a filter 28 operably connected across the DC bus 24; and

a storage capacitor 32 operably connected to the filter 28 with capacitor wires 30;

wherein the AC/DC converter 22, the DC bus 24, the filter 28, and the lamp driver 26 are disposed in the first housing 34;

the storage capacitor 32 is disposed in the second housing 36; and

the first housing 34 is thermally isolated and physically separated from the second housing 36.

15. The electronic ballast of claim 14 wherein the filter 28 comprises:

a filter capacitor 38;

a differential mode EMI coil 40; and

a common mode EMI coil 42, the common mode EMI coil 42 having a first EMI coil 44 magnetically coupled to a second EMI coil 46;

wherein the filter capacitor 38 is connected in parallel across the DC bus 24;

the differential mode EMI coil 40 and the first EMI coil 44 are connected in series between a first side of the DC bus 24 and a first conductor of the capacitor wires 30; and

the second EMI coil 46 is connected in series between a second side of the DC bus 24 and a second conductor of the capacitor wires 30.

16. The electronic ballast of claim 14 wherein the capacitor wires 30 are a shielded conductor pair with a shield 48 electrically connected to common.

17. The electronic ballast of claim 14 further comprising a space 60 formed between the first housing 34 and the second housing 36.

18. The electronic ballast of claim 14 further comprising a third housing 62 disposed between the first housing 34 and the second housing 36.

19. An electronic ballast comprising:

a first housing 34;

an AC/DC converter 22;

a DC bus 24 operably connected to the AC/DC converter 22;

a lamp driver 26 operably connected to the DC bus 24; and

a storage capacitor 32 operably connected to the DC bus 24 with capacitor wires 30;

wherein the AC/DC converter 22, the DC bus 24, and the lamp driver 26 are disposed in the first housing 34; and

the first housing 34 is thermally isolated and physically separated from the storage capacitor 32.

20. The electronic ballast of claim 19 further comprising a filter 28 electrically connected between the DC bus 24 and the capacitor wires 30, the filter 28 being disposed at the first housing 34.

21. The electronic ballast of claim 20 wherein the filter 28 comprises:

a filter capacitor 38;

a differential mode EMI coil 40; and

a common mode EMI coil 42, the common mode EMI coil 42 having a first EMI coil 44 magnetically coupled to a second EMI coil 46;

wherein the filter capacitor 38 is connected in parallel across the DC bus 24;

the differential mode EMI coil 40 and the first EMI coil 44 are connected in series between a first side of the DC bus 24 and a first conductor of the capacitor wires 30; and

the second EMI coil 46 is connected in series between a second side of the DC bus 24 and a second conductor of the capacitor wires 30.

22. The electronic ballast of claim 19 wherein the storage capacitor 32 comprises a plurality of capacitors.

23. The electronic ballast of claim 19 wherein the capacitor wires 30 are a shielded conductor pair with a shield 48 electrically connected to common.

24. The electronic ballast of claim 19 wherein the first housing 34 is selected from the group consisting of a metal housing and a plastic housing.