Digital load control system providing power and communication via existing power wiring

• US 10,231,317 B2
• Filed: 05/08/2017
• Issued: 03/12/2019
• Est. Priority Date: 01/17/2012
• Status: Active Grant

• Current Assignee: Lutron Technology Company LLC
• Original Assignee: Lutron Electronics Company Incorporated (Lutron Electronics)
• Inventors: Taipale, Mark S., Steiner, James P., Zaharchuk, Walter S., Pessina, Michael W., Spira, Joel S.
• Primary Examiner(s): Chen, Sibin
• Application Number:
  US15/589,472
• Publication Number:
  US 20170245353A1
• Time in Patent Office: 673 Days
• CPC Class Codes: H05B 45/10 Controlling the intensity of the light
• CPC Class Codes: H05B 47/11 by determining the brightness or colour temperature of ambient light
• CPC Class Codes: H05B 47/115 by determining the presence or movement of objects or living beings
• CPC Class Codes: H05B 47/185 via power line carrier transmission
• CPC Class Codes: H05B 47/19 via wireless transmission
• CPC Class Codes: Y02B 20/40 Control techniques providing energy savings, e.g. smart controller or presence detection

Abstract

A controller comprises a controllably conductive device adapted to be coupled in series electrical connection between an AC power source and a load control device. The controller also comprises a control circuit coupled to the controllably conductive device for rendering the controllably conductive device conductive each half-cycle of the AC power source to generate a phase-control voltage. The control circuit is operable to render the controllably conductive device conductive for a portion of each half-cycle of the AC power source. The control circuit is operable to transmit a digital message to the load control device for controlling the power delivered to the load by encoding digital information in timing edges of the phase-control voltage, where the phase-control voltage having at least one timing edge in each half-cycle of the AC power source when the control circuit is transmitting the digital message to the load control device.

Claims

1. A controller for controlling power delivered from an AC power source to an electrical load by a load control device, the controller comprising:

a controllably conductive device adapted to be coupled in series electrical connection between the AC power source and the load control device; and

a control circuit coupled to the controllably conductive device for rendering the controllably conductive device conductive each half-cycle of the AC power source to generate a phase-control voltage, the control circuit operable to render the controllably conductive device conductive for a portion of each half-cycle of the AC power source;

wherein the control circuit is operable to transmit a digital message to the load control device for controlling the power delivered to the load by encoding digital information in timing edges of the phase-control voltage, the phase-control voltage having at least one timing edge in each half-cycle of the AC power source when the control circuit is transmitting the digital message to the load control device.

2. The controller of claim 1, wherein the control circuit is operable to control the controllably conductive device each half-cycle to generate a number of sequential data patterns of the phase-control voltage, each data pattern characterized by a first timing edge at a predetermined reference edge time during a first half-cycle and a second timing edge at a data edge time during a second subsequent half-cycle, such that an offset time period exists between the reference edge time and the data edge time of each data pattern, the control circuit operable to transmit the digital message to the load control device by controlling the offset time period in each of the sequential data patterns.

3. The controller of claim 2, wherein the control circuit is operable to transmit the digital message to the load control device by adjusting the offset time period between the reference edge time during the first half-cycle and the data edge time during the second half-cycle to be one of a plurality of possible predetermined offset time periods.

4. The controller of claim 3, wherein the control circuit is operable to transmit digital messages to the load control device by adjusting the offset time period of each data pattern to one of four possible predetermined offset time periods.

5. The controller of claim 4, wherein the control circuit is operable to control the controllably conductive device to generate a third timing edge of the phase-control voltage at a data edge time during a third half-cycle immediately following the second half-cycle of each data pattern, such that a second offset time period exists between the reference edge time during the first half-cycle and the data edge time during the third half-cycle.

6. The controller of claim 4, wherein the control circuit is operable to control the controllably conductive device to generate a third timing edge of the phase-control voltage at a second reference edge time during a third half-cycle immediately following the second half-cycle and a fourth timing edge at a second data edge time during a fourth subsequent half-cycle, such that a second offset time period exists between the second reference edge time and the second data edge time.

7. The controller of claim 4, wherein a duration of one of the possible predetermined offset time periods is approximately the length of a half-cycle of the AC power source.

8. The controller of claim 7, wherein the possible predetermined offset time periods differ by approximately 100 microseconds.

9. The controller of claim 8, wherein a rise time of the phase-control voltage when the control circuit renders the controllably conductive device conductive is less than approximately 10 microseconds.

10. The controller of claim 2, further comprising:

a zero-crossing detector for generating a control signal representative of the zero-crossings of the AC power source;

wherein the control circuit is operable to receive the control signal representative of the zero-crossings of the AC power source and to render the controllably conductive device conductive at the reference edge time relative to the zero-crossing of the first half-cycle.

11. The controller of claim 10, wherein the control circuit is operable to render the controllably conductive device conductive at the data edge time in the second half-cycle relative to the reference edge time of the first half-cycle.

12. The controller of claim 1, wherein the controller comprises a two-wire device.

13. The controller of claim 12, further comprising:

a power supply coupled in parallel electrical connection with the controllably conductive device for conducting a charging current to generate a supply voltage for powering the control circuit.

14. The controller of claim 13, further comprising:

a current limit circuit coupled in series electrical connection with the power supply for limiting a magnitude of the charging current.

15. The controller of claim 12, wherein the controllably conductive device is operable to conduct a load current from the AC power source to the electrical load.

16. The controller of claim 1, further comprising:

an RF receiver coupled to the control circuit for receiving an RF signal;

wherein the control circuit is operable to transmit the digital message to the load control device for controlling the power delivered to the load in response to the received RF signal.

17. The controller of claim 16, wherein the RF receiver is operable to receive an RF signal from one of a plurality of RF transmitters, the control circuit operable to adjust data representing a channel of the digital message transmitted to the load control device in response to the one of the RF transmitters from which the RF signal was received.

18. The controller of claim 1, wherein the phase-control voltage comprises a forward phase-control voltage, and each timing edge comprising a rising edge of the phase-control voltage.

19. The controller of claim 1, wherein the phase-control voltage comprises a reverse phase-control voltage, and each timing edge comprising a falling edge of the phase-control voltage.

20. The controller of claim 1, further comprising:

a neutral terminal adapted to be coupled to a neutral side of the AC power source.

21. The controller of claim 1, wherein the control circuit is operable to alternately operate in a dimmer mode and a digital communication mode, the control circuit operable to render the controllably conductive device conductive each half-cycle at a phase angle that is dependent upon a desired lighting intensity of the electrical load when operating in the dimmer mode, the control circuit operable to transmit the digital message by encoding digital information for controlling the intensity of the electrical load in the timing edges of the phase-control voltage when operating in the digital communication mode.

22. The controller of claim 1, wherein the phase-control voltage has at least one timing edge in each half-cycle of the AC power source when the control circuit is transmitting a digital message to the load control device and when the control circuit is not transmitting a digital message to the load control device.

23. The controller of claim 1, wherein the control circuit is operable to render the controllably conductive device fully conductive for a plurality of consecutive half-cycles when the control circuit is not transmitting a digital message to the load control device.

24. A controller for controlling power delivered from an AC power source to a lighting load, the controller comprising:

a controllably conductive device adapted to be coupled in series electrical connection between the AC power source and the lighting load; and

a control circuit coupled to the controllably conductive device for rendering the controllably conductive device conductive for a portion of each half-cycle of the AC power source for generating a phase-control voltage to control an intensity of lighting load;

wherein the control circuit is operable to alternately operate in a dimmer mode and a digital communication mode, the control circuit operable to render the controllably conductive device conductive each half-cycle at a phase angle that is dependent upon a desired lighting intensity when operating in the dimmer mode, the control circuit operable to transmit digital messages by encoding digital information for controlling the intensity of the lighting load in timing edges of the phase-control voltage when operating in the digital communication mode.

25. The controller of claim 24, wherein the control circuit is field-configurable to change between the dimmer mode and the digital communication mode.

26. The controller of claim 25, wherein the control circuit is configured to change between the dimmer mode and the digital communication mode using an advanced programming mode.