EMERGENCY LIGHTING SYSTEMS AND METHODS FOR SOLID STATE LIGHTING APPARATUS

• US 20130127362A1
• Filed: 05/08/2012
• Published: 05/23/2013
• Est. Priority Date: 12/12/2011
• Status: Active Grant

• Current Assignee: IDEAL Industries Lighting, LLC (Ideal Industries Incorporated)
• Original Assignee: CREE Incorporated (Wolfspeed, Inc.)
• Inventors: Harris, Michael James, Trainor, John J., McBryde, James A., Powere, Randell L., O'Flaherly, Patrick J.
• Granted Patent: US 9,835,691 B2
• Time in Patent Office: Days
• US Class Current: 315/224
• CPC Class Codes: F21S 9/022 Emergency lighting devices
• CPC Class Codes: G01R 31/40 Testing power supplies testing photovoltaic devices H02S50/10
• CPC Class Codes: G01R 31/44 Testing lamps
• CPC Class Codes: H02J 9/065 for lighting purposes
• CPC Class Codes: H05B 45/10 Controlling the intensity of the light
• CPC Class Codes: H05B 45/12 using optical feedback
• CPC Class Codes: H05B 45/18 using temperature feedback
• CPC Class Codes: H05B 45/38 using boost topology
• CPC Class Codes: H05B 47/105 in response to determined parameters
• CPC Class Codes: H05B 47/17 Operational modes, e.g. switching from manual to automatic mode or prohibiting specific operations
• CPC Class Codes: H05B 47/19 via wireless transmission
• CPC Class Codes: H05B 47/195 the transmission using visible or infrared light

Abstract

An emergency lighting module for providing emergency power to a solid state luminaire. The emergency lighting module includes a first input configured to receive a DC input voltage from the solid state luminaire, a second input configured to receive a status signal indicative of the status of an AC line voltage, and a first output configured to supply a DC output voltage to the solid state luminaire. The emergency lighting module is configured to supply the DC output voltage to the solid state luminaire in response to a reduction of the AC line voltage.

Claims

1. An emergency lighting module for providing emergency power to a solid state luminaire, the emergency lighting module comprising:

a first input configured to receive a DC input voltage from the solid state luminaire;

a second input configured to receive a status signal indicative of the status of an AC line voltage; and

a first output configured to supply a DC output voltage to the solid state luminaire;

wherein the emergency lighting module is configured to supply the DC output voltage to the solid state luminaire in response to a reduction of the AC line voltage.

2. The emergency lighting module of claim 1, wherein the signal indicative of the status of the AC line voltage comprises an AC line signal and/or a rectified AC line signal.

3. The emergency lighting module of claim 1, further comprising:

a charging circuit configured to receive the DC input voltage from the solid state luminaire and responsively generate a charging signal for charging a rechargeable battery coupled to the emergency lighting module.

4. The emergency lighting module of claim 1, wherein the emergency lighting module is configured to monitor the DC input voltage to detect a brownout condition of the AC line voltage.

5. The emergency lighting module of claim 1, wherein the emergency lighting module comprises a second output configured to supply an AC signal to the luminaire.

6. The emergency lighting module of claim 1, wherein the emergency lighting module is configured to supply a control signal to the luminaire that disables an AC/DC converter of the luminaire in response to reduction of the AC line voltage.

7. The emergency lighting module of claim 1, wherein the emergency lighting module is configured to supply a dimming control signal to the luminaire in response to reduction of the AC line voltage.

8. The emergency lighting module of claim 7, wherein the dimming control signal comprises a pulse width modulation (PWM) control signal.

9. The emergency lighting module of claim 8, further comprising a microcontroller configured to monitor the power status signal and to generate the PWM control signal in response to reduction of the AC line voltage.

10. The emergency lighting module of claim 9, wherein the microcontroller is configured to generate the PWM control signal to have a target duty cycle;

and wherein the microcontroller is configured to initially generate the PWM control signal to have a first duty cycle that is lower than the target duty cycle and to increase the duty cycle of the PWM control signal from the first duty cycle to the target duty cycle.

11. The emergency lighting module of claim 10, wherein the microcontroller is configured to decrease the duty cycle of the PWM control signal from the target duty cycle to a final duty cycle that is lower than the target duty cycle.

12. The emergency lighting module of claim 11, wherein the microcontroller is configured to maintain the duty cycle of the PWM control signal at the final duty cycle until the AC line voltage is restored or until battery capacity is exceeded.

13. The emergency lighting module of claim 9, further comprising an AC detector configured to detect a presence of the AC line voltage and to supply an AC detection signal to the microcontroller in response to presence of the AC line voltage.

14. The emergency lighting module of claim 9, further comprising an analog to digital converter configured to receive the DC input voltage and provide a digital signal indicative of a voltage level of the DC input voltage to the microcontroller.

15. The emergency lighting module of claim 9, further comprising:

a charging circuit coupled to the microcontroller, wherein the charging circuit is configured to receive the DC input voltage from the solid state luminaire and to receive a charging control signal from the microcontroller, and responsively generate a charging signal for charging a rechargeable battery coupled to the emergency lighting module; and

a voltage booster circuit coupled to the microcontroller and configured to receive a voltage booster control signal from the microcontroller and a DC battery voltage from the rechargeable battery and responsively generate the DC output voltage that is supplied to the solid state luminaire.

16. The emergency lighting module of claim 15, wherein the microcontroller is configured to cause the voltage booster circuit to generate the DC output voltage in response to reduction of the AC line voltage.

17. The emergency lighting module of claim 16, wherein the microcontroller is configured to cause the voltage booster circuit to generate the DC output voltage to have a voltage level that increases from a first voltage level to a maximum voltage level at a first ramping speed in response to reduction of the AC line voltage.

18. The emergency lighting module of claim 1, wherein the emergency lighting module is configured to ramp the DC output voltage up from an initial voltage level to a target voltage level in response to detecting reduction of the AC line signal.

19. An emergency lighting module for providing emergency power to a solid state luminaire, the emergency lighting module comprising:

a microcontroller;

an AC detector coupled to the microcontroller and configured to detect a presence of an AC line signal;

a first input configured to receive a DC input voltage from the solid state luminaire;

a battery charger coupled to the microcontroller and configured to charge a battery using the DC input voltage in response to a first control signal from the microcontroller; and

a voltage booster coupled to the microcontroller and configured to generate a DC output signal in response to a battery voltage and a second control signal from the microcontroller;

wherein the emergency lighting module is configured to supply the DC output to the solid state luminaire in response to a reduction of the AC line voltage.

20. The emergency lighting module of claim 19, wherein the emergency lighting module is configured to supply a dimming control signal to the luminaire in response to reduction of the AC line voltage.

21. An emergency lighting module for providing emergency power to a solid state luminaire, the emergency lighting module comprising:

a microcontroller; and

an AC detector coupled to the microcontroller and configured to detect a presence of an AC line signal;

wherein the emergency lighting module is configured to supply a dimming control signal to the luminaire in response to reduction of the AC line voltage.

22. The emergency lighting module of claim 21, wherein the microcontroller is configured to receive a module identification signal from the luminaire;

and

wherein the microcontroller is configured to generate the dimming control signal in response to the module identification signal.

23. The emergency lighting module of claim 21, wherein the microcontroller is configured to receive a battery identification signal from a battery.

24. The emergency lighting module of claim 23, wherein the microcontroller is configured to generate the dimming control signal in response to the battery identification signal.

25. The emergency lighting module of claim 23, wherein the microcontroller is configured to control charging of the battery in response to the battery identification signal.

26. The emergency lighting module of claim 21, further comprising a field-replaceable battery pack that houses the battery.

27. A method of operating an emergency lighting module for providing emergency power to a solid state luminaire, comprising:

monitoring an AC line voltage;

generating a DC voltage in response to reduction of the AC line voltage; and

supplying the DC voltage to the solid state luminaire in response to reduction of the AC line voltage.

28. The method of claim 27, further comprising:

generating a dimming control signal and supplying the dimming control signal to the solid state luminaire in response to reduction of the AC line voltage.

29. The method of claim 28, wherein the dimming control signal comprises a pulse width modulation (PWM) signal.

30. The method of claim 29 further comprising initially generating the PWM control signal to have a first duty cycle that is lower than a target duty cycle and increasing the duty cycle of the PWM control signal from the first duty cycle to the target duty cycle.

31. The method of claim 30, further comprising decreasing the duty cycle of the PWM control signal from the target duty cycle to a final duty cycle that is lower than the target duty cycle.

32. The method of claim 31, further comprising maintaining the duty cycle of the PWM control signal at the final duty cycle until the AC line voltage is restored.

33. A method of testing a solid state luminaire including a test switch, using an emergency lighting module including a battery, the method comprising:

monitoring the test switch for actuation;

in response to actuation of the test switch, determining if the test switch was actuated for more than a threshold time;

in response to the actuation of the test switch for more than the threshold of time, operating the solid state luminaire on battery power for a test period in excess of one hour without requiring continued actuation of the test switch during the test period; and

supplying a dimming signal to the solid state luminaire during the test period.

34. The method of claim 33, wherein the dimming signal causes the solid state luminaire to become more dim over a duration of the test period.

35. The method of claim 33, further comprising:

in response to actuation of the test switch, checking a charge level of the battery; and

in response to the charge level of the battery being less than a threshold charge level, ignoring the test switch actuation.

36. The method of claim 33, further comprising:

in response to the actuation of the test switch for less than the threshold of time, operating the solid state luminaire on battery power for a shortened test period.

37. An emergency lighting module for providing emergency power to a solid state luminaire, the emergency lighting module comprising:

a microcontroller;

an AC detector coupled to the microcontroller and configured to detect a presence of an AC line signal, wherein the emergency lighting module is configured to supply a DC voltage and a dimming control signal to the luminaire in response to reduction of the AC line voltage;

a test switch coupled to the microcontroller, wherein the microcontroller is configured to test operation of the emergency lighting controller in response to actuation of the test switch; and

a wireless interface coupled to the test switch and configured to enable wireless actuation of the test switch.

38. The emergency lighting module of claim 37, wherein the wireless interface comprises a visible light detector that is configured to actuate the test switch in response to a visible light signal.

39. The emergency lighting module of claim 37, wherein the wireless interface comprises an infrared detector that is configured to actuate the test switch in response to an infrared signal.

40. The emergency lighting module of claim 37, wherein the wireless interface comprises a bluetooth receiver that is configured to actuate the test switch in response to a bluetooth signal.

41. The emergency lighting module of claim 37, wherein the wireless interface comprises a WIFI detector that is configured to actuate the test switch in response to a WIFI signal.

42. An emergency lighting module for providing emergency power to a solid state luminaire, the emergency lighting module comprising:

a first input configured to receive a DC input voltage from the solid state luminaire;

a second input configured to receive a status signal indicative of the status of an AC line voltage;

a third input configured to receive a module type signal from the solid state luminaire; and

a first output configured to supply a DC output voltage to the solid state luminaire; and

a second output configured to supply a dimming control signal to the solid state luminaire;

wherein the emergency lighting module is configured to supply the DC output voltage and the dimming control signal to the solid state luminaire in response to a reduction of the AC line voltage; and

wherein the dimming control signal is selected in response to the module type signal.

43. The emergency lighting module of claim 42, wherein the dimming control signal comprises a pulse width modulation (PWM) control signal, and wherein a duty cycle of the PWM control signal is selected in response to the module type signal.

44. The emergency lighting module of claim 42, wherein the dimming control signal is selected to cause the solid state luminaire to generate a predetermined light output regardless of a lumen rating of the solid state luminaire.