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

• US 10,159,139 B2
• Filed: 04/20/2018
• Issued: 12/18/2018
• Est. Priority Date: 03/14/2013
• Status: Active Grant

• Current Assignee: Lutron Technology Company LLC
• Original Assignee: Lutron Electronics Company Incorporated (Lutron Electronics)
• Inventors: Taipale, Mark S., Gredler, Timothy P., Bhat, Akshay
• Primary Examiner(s): Owens, Douglas W
• Assistant Examiner(s): Fernandez, Pedro C
• Application Number:
  US15/958,702
• Publication Number:
  US 20180242431A1
• Time in Patent Office: 242 Days
• 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 45/37 Converter circuits
• CPC Class Codes: H05B 45/375 using buck topology
• CPC Class Codes: H05B 45/38 using boost topology
• CPC Class Codes: H05B 47/105 in response to determined parameters
• CPC Class Codes: H05B 47/11 by determining the brightness or colour temperature of ambient light
• CPC Class Codes: H05B 47/13 by using passive infrared detectors
• CPC Class Codes: H05B 47/185 via power line carrier transmission
• CPC Class Codes: H05B 47/19 via wireless transmission
• CPC Class Codes: H05B 47/195 the transmission using visible or infrared light
• CPC Class Codes: Y02B 20/40 Control techniques providing energy savings, e.g. smart controller or presence detection

Abstract

A two-way load control system comprises a power device, such as a load control device for controlling an electrical load receiving power from an AC power source, and a controller adapted to be coupled in series between the source and the power device. The load control system may be installed without requiring any additional wires to be run, and is easily configured without the need for a computer or an advanced commissioning procedure. The power device receives both power and communication over two wires. The controller generates a phase-control voltage and transmits a forward digital message to the power device by encoding digital information in timing edges of the phase-control voltage. The power device transmits a reverse digital message to the controller via the power wiring.

Claims

1. A method for controlling power delivered from a power source to an electrical load, the method comprising:

transmitting a forward digital message to a power device via an electrical wiring by encoding digital information in timing edges of a periodic voltage;

receiving a reverse digital message from the power device via the electrical wiring; and

transmitting a short pattern immediately prior to the power device transmitting the reverse digital message, the short pattern configured to synchronize the power device to a frequency of the periodic voltage;

wherein the forward digital message comprises a command for causing the power device to control the power delivered to the electrical load, and wherein the short pattern has a length shorter than a length of the forward digital message.

2. The method of claim 1, further comprising:

controlling a controllably conductive device to generate the periodic voltage;

wherein a controller voltage is generated across the controllably conductive device, and wherein receiving the reverse digital message comprises decoding digital information in the controller voltage.

3. The method of claim 2, wherein the periodic voltage comprises a phase-control voltage, the controllably conductive device adapted to be coupled in series electrical connection between an AC power source and the power device for generating the phase-control voltage.

4. The method of claim 3, wherein receiving the reverse digital message comprises receiving a bit of the reverse digital message prior to when the controllably conductive device is rendered conductive during a half-cycle of the AC power source.

5. The method of claim 4, wherein transmitting the forward digital message further comprises rendering the controllably conductive device conductive to generate a first timing edge at a predetermined reference edge time during a first half cycle of a data pattern of the reverse digital message, wherein a window time period exists during a second half-cycle of the data pattern after a zero-crossing of the second half-cycle, a beginning of the window time period being approximately one half-cycle duration after the predetermined reference edge time.

6. The method of claim 4, wherein receiving the reverse digital message further comprises monitoring a magnitude of the controller voltage during the window time period to receive the bit of the reverse digital message.

7. The method of claim 1, wherein the reverse digital message is split up into a number of packets, and wherein transmitting the short pattern comprises transmitting a continuation pattern between the packets.

8. The method of claim 7, further comprising:

beginning a transmission of a new forward digital message by transmitting a start pattern rather than transmitting the continuation pattern after one of the packets of the reverse digital message.

9. The method of claim 7, wherein transmitting the continuation pattern comprises transmitting the continuation pattern before the power device has transmitted an entirety of the reverse digital message.

10. The method of claim 1, wherein transmitting the short pattern comprises transmitting a retry pattern if the reverse digital message has an error, and wherein the retry pattern is configured to cause the power device to retransmit the reverse digital message.

11. A method for communicating digital messages comprising:

generating a periodic voltage on an electrical wiring that is adapted to be coupled to a power device;

transmitting a forward digital message to the power device via the electrical wiring by encoding digital information in timing edges of the periodic voltage;

receiving a reverse digital message from the power device via the electrical wiring; and

transmitting a short pattern immediately prior to the power device transmitting the reverse digital message, the short pattern configured to synchronize the power device to a frequency of the periodic voltage, and wherein the short pattern has a length shorter than a length of the forward digital message.

12. The method of claim 11, wherein the reverse digital message is split up into a number of packets, and wherein transmitting the short pattern comprises transmitting a continuation pattern between the packets.

13. The method of claim 12, further comprising:

beginning a transmission of a new forward digital message by transmitting a start pattern rather than transmitting the continuation pattern after one of the packets of the reverse digital message.

14. The method of claim 12, wherein transmitting the continuation pattern comprises transmitting the continuation pattern before the power device has transmitted an entirety of the reverse digital message.

15. The method of claim 11, wherein transmitting the short pattern comprises transmitting a retry pattern if the reverse digital message has an error, and wherein the retry pattern is configured to cause the power device to retransmit the reverse digital message.

16. A method for communicating digital messages comprising:

receiving a periodic voltage from a controller via an electrical wiring;

decoding a forward digital message in response to digital information encoded in timing edges of the periodic voltage received from the controller via the electrical wiring;

transmitting a reverse digital message to the controller via the electrical wiring; and

receiving a short pattern from the controller immediately prior to a power device transmitting the reverse digital message, the short pattern configured to synchronize the power device to a frequency of the periodic voltage, and wherein the short pattern has a length shorter than a length of the forward digital message.

17. The method of claim 16, wherein the reverse digital message is split up into a number of packets, and wherein receiving a short pattern comprises receiving a continuation pattern between transmissions of the packets of the reverse digital message.

18. The method of claim 17, further comprising:

receiving a start pattern to begin receiving a new forward digital message rather than receiving the continuation pattern after transmitting one of the packets of the reverse digital message.

19. The method of claim 17, further comprising:

measuring a period of the periodic voltage using the continuation pattern.

20. The method of claim 17, wherein receiving the continuation pattern comprises receiving the continuation pattern before the reverse digital message has been transmitted in its entirety.

21. The method of claim 16, wherein receiving a short pattern comprises receiving a retry pattern if the reverse digital message has an error, the method further comprising retransmitting the reverse digital message after receiving the retry pattern.