Systems and methods for low-power lamp compatibility with a trailing-edge dimmer and an electronic transformer

• US 9,167,664 B2
• Filed: 03/13/2013
• Issued: 10/20/2015
• Est. Priority Date: 07/03/2012
• Status: Active Grant

• Current Assignee: Signify Holding B.V. (Signify N.V.)
• Original Assignee: Cirrus Logic Incorporated
• Inventors: Xie, Yanhui, King, Eric Jerome, Melanson, John L., Kost, Michael A.
• Primary Examiner(s): VU, JIMMY T
• Application Number:
  US13/798,926
• Publication Number:
  US 20140009078A1
• Time in Patent Office: 951 Days
• Field of Search: 315/209.R, 315/276, 315/291, 315/307, 315/308, 315/224, 315/225
• US Class Current: 1/1
• CPC Class Codes: H05B 45/10 Controlling the intensity of the light
• CPC Class Codes: H05B 45/315 Reverse phase-control circuits
• CPC Class Codes: H05B 45/37 Converter circuits
• CPC Class Codes: H05B 47/17 Operational modes, e.g. switching from manual to automatic mode or prohibiting specific operations
• CPC Class Codes: Y02B 20/30 Semiconductor lamps, e.g. solid state lamps [SSL] light emitting diodes [LED] or organic LED [OLED]

Abstract

In accordance with these and other embodiments of the present disclosure, a system and method for providing compatibility between a load and a secondary winding of an electronic transformer driven by a trailing-edge dimmer may include predicting based on an electronic transformer secondary signal an estimated occurrence of a high-resistance state of the trailing-edge dimmer, wherein the high-resistance state occurs when the trailing-edge dimmer begins phase-cutting an alternating current voltage signal and operating the load in a high-current mode for a period of time immediately prior to the estimated occurrence of the high-resistance state.

Claims

1. A lighting apparatus comprising:

a controller to provide compatibility between a load and a secondary winding of an electronic transformer driven by a trailing-edge dimmer, wherein the controller is configured to;

predict based on an electronic transformer secondary signal an estimated occurrence of a high-resistance state of the trailing-edge dimmer, wherein the high-resistance state occurs when the trailing-edge dimmer begins phase-cutting an alternating current voltage signal; and

operate in a high-current mode for a period of time immediately prior to the estimated occurrence of the high-resistance state.

2. The apparatus of claim 1, the controller further configured to operate in a low-impedance mode immediately after the estimated occurrence of the high-resistance state.

3. The apparatus of claim 1, the controller further configured to:

predict based on the electronic transformer secondary signal an estimated occurrence of a trigger event of the electronic transformer, the trigger event corresponding to a rise in an output voltage of the dimmer; and

operate in a high-impedance mode immediately after the estimated occurrence of the trigger event and immediately prior to the high-current mode.

4. The apparatus of claim 3, the controller further configured to operate in a low-impedance mode immediately prior to the estimated occurrence of the high-resistance state.

5. The apparatus of claim 4, the controller further configured to sequentially and cyclically operate in the high-current mode, the low-impedance mode, and the high-impedance mode.

6. The apparatus of claim 1, wherein the controller is further configured to determine a target amount of energy to be delivered to the load during a particular operation in the high-current mode, the target amount of energy based on a control setting of the dimmer.

7. The apparatus of claim 6, the controller configured to:

determine an estimated delivered amount of energy actually delivered to the load during the particular operation in the high-current mode;

calculate an error based on the difference between the target amount of energy and the estimated delivered amount of energy; and

in a subsequent operation in the high-current mode occurring after the particular operation in the high-current mode, determine a second target amount of energy to be delivered to the load during the subsequent operation in the high-current mode, the second target amount of energy based on the error and the control setting of the dimmer.

8. The apparatus of claim 6, the controller further configured to:

predict based on the electronic transformer secondary signal an estimated occurrence of a trigger event of the electronic transformer;

operate in a high-impedance mode immediately after the estimated occurrence of the trigger event and immediately prior to the high-current mode; and

estimate the control setting of the dimmer based on an aggregate duration of the high-current mode and the high-impedance mode.

9. The apparatus of claim 6, wherein the controller is configured to, for each n-th operation of the high-current mode:

predict based on the electronic transformer secondary signal an estimated occurrence of a trigger event of the electronic transformer; and

operate in the high-current mode from the estimated occurrence of the trigger event to the estimated occurrence of the high-impedance mode.

10. The apparatus of claim 9, wherein n is an odd positive integer.

11. The apparatus of claim 1, the period of time based on a control setting of the dimmer.

12. The apparatus of claim 11, the controller further configured to:

predict based on the electronic transformer secondary signal an estimated occurrence of a trigger event of the electronic transformer;

operate in a high-impedance mode immediately after the estimated occurrence of the trigger event and immediately prior to the high-current mode; and

estimate the control setting of the dimmer based on an aggregate duration of the high-current mode and the high-impedance mode.

13. The apparatus of claim 1, wherein the load comprises a lamp.

14. The apparatus of claim 13, wherein the lamp comprises a light-emitting diode lamp.

15. The apparatus of claim 13, wherein the lamp comprises a lamp having a multifaceted reflector form factor.

16. A method of using a controller for providing compatibility between a load and a secondary winding of an electronic transformer driven by a trailing-edge dimmer comprising:

predicting based on an electronic transformer secondary signal an estimated occurrence of a high-resistance state of the trailing-edge dimmer, wherein the high-resistance state occurs when the trailing-edge dimmer begins phase-cutting an alternating current voltage signal; and

operating the load in a high-current mode for a period of time immediately prior to the estimated occurrence of the high-resistance state.

17. The method of claim 16, further comprising operating in a low-impedance mode immediately after the estimated occurrence of the high-resistance state.

18. The method of claim 16, further comprising:

predicting based on the electronic transformer secondary signal an estimated occurrence of a trigger event of the electronic transformer, the trigger event corresponding to a rise in an output voltage of the dimmer; and

operating the load in a high-impedance mode immediately after the estimated occurrence of the trigger event and immediately prior to the high-current mode.

19. The method of claim 18, further comprising operating the load in a low-impedance mode immediately prior to the estimated occurrence of the high-resistance state.

20. The method of claim 19, further comprising sequentially and cyclically operating the load in the high-current mode, the low-impedance mode, and the high-impedance mode.

21. The method of claim 16, further comprising determining a target amount of energy to be delivered to the load during a particular operation in the high-current mode, the target amount of energy based on a control setting of the dimmer.

22. The method of claim 21, further comprising:

determining an estimated delivered amount of energy actually delivered to the load during the particular operation in the high-current mode;

calculating an error based on the difference between the target amount of energy and the estimated delivered amount of energy; and

in a subsequent operation in the high-current mode occurring after the particular operation in the high-current mode, determining a second target amount of energy to be delivered to the load during the subsequent operation in the high-current mode, the second target amount of energy based on the error and the control setting of the dimmer.

23. The method of claim 21, further comprising:

predicting based on the electronic transformer secondary signal an estimated occurrence of a trigger event of the electronic transformer;

operating the load in a high-impedance mode immediately after the estimated occurrence of the trigger event and immediately prior to the high-current mode; and

estimating the control setting of the dimmer based on an aggregate duration of the high-current mode and the high-impedance mode.

24. The method of claim 21, further comprising, for each n-th operation of the high-current mode:

predicting based on the electronic transformer secondary signal an estimated occurrence of a trigger event of the electronic transformer; and

operating the load in the high-current mode from the estimated occurrence of the trigger event to the estimated occurrence of the high-impedance mode.

25. The method of claim 24, wherein n is an odd positive integer.

26. The method of claim 16, the period of time based on a control setting of the dimmer.

27. The method of claim 26, further comprising:

predicting based on the electronic transformer secondary signal an estimated occurrence of a trigger event of the electronic transformer;

operating the load in a high-impedance mode immediately after the estimated occurrence of the trigger event and immediately prior to the high-current mode; and

estimating the control setting of the dimmer based on an aggregate duration of the high-current mode and the high-impedance mode.

28. The method of claim 16, wherein the load comprises a lamp.

29. The method of claim 28, wherein the lamp comprises a light-emitting diode lamp.

30. The method of claim 28, wherein the lamp comprises a multifaceted reflector form factor.