Thermal Management In A Lighting System Using Multiple, Controlled Power Dissipation Circuits

• US 20120112638A1
• Filed: 11/04/2011
• Published: 05/10/2012
• Est. Priority Date: 11/04/2010
• Status: Active Grant

• Current Assignee: Signify Holding B.V. (Signify N.V.)
• Original Assignee: Philips Lighting Holding BV (Signify N.V.)
• Inventors: Melanson, John L., King, Eric J.
• Granted Patent: US 9,497,851 B2
• Time in Patent Office: Days
• US Class Current: 315/117
• CPC Class Codes: H05B 45/00 Circuit arrangements for operating light-emitting diodes [LED]
• CPC Class Codes: H05B 45/10 Controlling the intensity of the light
• CPC Class Codes: H05B 45/3725 Switched mode power supply [SMPS]
• CPC Class Codes: H05B 45/395 Linear regulators
• CPC Class Codes: H05B 45/44 with an active control inside an LED matrix
• CPC Class Codes: H05B 45/46 having LEDs disposed in parallel lines
• CPC Class Codes: H05B 47/10 Controlling the light source
• CPC Class Codes: H05K 1/0203 Cooling of mounted components H05K1/0272 takes precedence
• CPC Class Codes: Y02B 20/00 Energy efficient lighting technologies, e.g. halogen lamps or gas discharge lamps
• CPC Class Codes: Y02B 20/30 Semiconductor lamps, e.g. solid state lamps [SSL] light emitting diodes [LED] or organic LED [OLED]

Abstract

A lighting system includes a controller that is configured to provide thermal management for the lighting system by distributing excess energy in the lighting system through multiple power dissipation circuits. In at least one embodiment, the lighting system is a phase cut compatible, dimmable lighting system having one or more light sources selected from a group consisting of at least one light emitting diode and at least one compact fluorescent lamp. In at least one embodiment, the controller is configured to control the plurality of power dissipation circuits in accordance with a thermal management strategy to dissipate the excess energy in the phase cut compatible, dimmable lighting system. The particular thermal management strategy is a matter of design choice. The power distribution circuits include two of more of: a controlled switch path power dissipation circuit, a controlled link path power dissipation circuit, and a controlled flyback path power dissipation circuit.

Claims

1. An apparatus comprising:

a controller configured to control a plurality of power dissipation circuits in accordance with a thermal management strategy to dissipate excess energy in a phase cut compatible, dimmable lighting system having one or more light sources selected from a group consisting of at least one light emitting diode and at least one compact fluorescent lamp.

2. The apparatus of claim 1 wherein the power dissipation circuits include two or more power dissipation circuits selected from a group consisting of:

a controlled switch path power dissipation circuit, a controlled link path power dissipation circuit, and a controlled flyback path power dissipation circuit.

3. The apparatus of claim 2 wherein the controlled switch path power dissipation circuit is configured to dissipate excess energy by at least a boost switch of a switching power converter during a controlled power dissipation phase, and the controlled power dissipation phase occurs after a charging phase begins and before an end of a subsequent flyback phase of the switching power converter.

4. The apparatus of claim 2 wherein the controlled link path power dissipation circuit is configured to dissipate excess energy to dissipate power in a link path of a switching power converter.

5. The apparatus of claim 2 wherein the controlled flyback path power dissipation circuit is configured to dissipate excess energy by at least a flyback switch during a controlled power dissipation phase, and the controlled power dissipation phase occurs after a charging phase begins and before an end of a subsequent flyback phase of a switching power converter.

6. The apparatus of claim 1 wherein the excess energy comprises energy received by a switching power converter that is greater than an amount of energy to be provided to a load coupled to the switching power converter.

7. The apparatus of claim 1 wherein at least one of the power dissipation circuits is included in a switching power converter.

8. The apparatus of claim 1 wherein the power dissipation circuits are included in power conversion circuitry.

9. The apparatus of claim 1 wherein the controller is further configured to dynamically distribute power dissipation to the power dissipation circuits in response to observed events in the lighting system and in accordance with the thermal management strategy.

10. The apparatus of claim 1 wherein the one or more observed events are selected from a group consisting of:

local temperature measurements and activity of each of the power dissipation circuits.

11. The apparatus of claim 1 wherein the controller is further configured to distribute power dissipation to the power dissipation circuits in a preset manner in accordance with the thermal management strategy.

12. The apparatus of claim 1 wherein the controller includes at least one terminal to receive thermal management strategy data, wherein the thermal management strategy data at least in part establishes the thermal management strategy.

13. The apparatus of claim 1 wherein the controller is further configured to receive temperature data from a plurality of thermal sensors control the plurality of power dissipation circuits in accordance with a thermal management strategy that includes distributing power dissipation to the power dissipation circuits in accordance with the temperature data.

14. The apparatus of claim 1 wherein the thermal management strategy data is specific to a particular type of lighting system.

15. An method comprising:

controlling a plurality of power dissipation circuits in accordance with a thermal management strategy to dissipate excess energy in a phase cut compatible, dimmable lighting system having one or more light sources selected from a group consisting of at least one light emitting diode and at least one compact fluorescent lamp.

16. The method of claim 15 wherein the power dissipation circuits include two or more power dissipation circuits selected from a group consisting of:

a controlled switch path power dissipation circuit, a controlled link path power dissipation circuit, and a controlled flyback path power dissipation circuit.

17. The method of claim 16 further comprising:

controlling a boost switch of the controlled switch path power dissipation circuit during a controlled power dissipation phase to dissipate at least a part of the excess energy, and the controlled power dissipation phase occurs after a charging phase begins and before an end of a subsequent flyback phase of the switching power converter.

18. The method of claim 16 further comprising:

controlling the link path power dissipation circuit to dissipate at least part of the excess energy in a link path of a switching power converter.

19. The method of claim 16 further comprising:

controlling the flyback path power dissipation circuit to dissipate excess energy by at least a flyback switch during a controlled power dissipation phase, and the controlled power dissipation phase occurs after a charging phase begins and before an end of a subsequent flyback phase of a switching power converter.

20. The method of claim 15 wherein the excess energy comprises energy received by a switching power converter that is greater than an amount of energy to be provided to a load coupled to the switching power converter.

21. The method of claim 15 wherein at least one of the power dissipation circuits is included in a switching power converter.

22. The method of claim 15 wherein the power dissipation circuits are included in power conversion circuitry.

23. The method of claim 15 further comprising:

dynamically distributing power dissipation to the power dissipation circuits in response to observed events in the lighting system and in accordance with the thermal management strategy.

24. The method of claim 15 wherein the one or more observed events are selected from a group consisting of:

local temperature measurements and activity of each of the power dissipation circuits.

25. The method of claim 15 further comprising:

distributing power dissipation to the power dissipation circuits in a preset manner in accordance with the thermal management strategy.

26. The method of claim 15 wherein the controller includes at least one terminal to receive thermal management strategy data, wherein the thermal management strategy data at least in part establishes the thermal management strategy.

27. The method of claim 15 further comprising:

receiving temperature data from a plurality of thermal sensors control the plurality of power dissipation circuits in accordance with a thermal management strategy; and

distributing power dissipation to the power dissipation circuits in accordance with the temperature data.

28. The method of claim 15 wherein the thermal management strategy data is specific to a particular type of lighting system.

29. An apparatus comprising:

means for controlling a plurality of power dissipation circuits in accordance with a thermal management strategy to dissipate excess energy in a phase cut compatible, dimmable lighting system having one or more light sources selected from a group consisting of at least one light emitting diode and at least one compact fluorescent lamp.