DIGITAL LOAD CONTROL SYSTEM PROVIDING POWER AND COMMUNICATION VIA EXISTING POWER WIRING

• US 20160295670A1
• Filed: 06/13/2016
• Published: 10/06/2016
• 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
• Granted Patent: US 9,538,618 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• 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 controller for use in a load control system for controlling the power delivered from an AC power source to an electrical load, the controller comprising:

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

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 transmit a forward digital message to the power device by encoding digital information in timing edges of the phase-control voltage; and

a reverse receiving circuit coupled in parallel electrical connection with the controllably conductive device;

wherein the control circuit is operatively coupled to the reverse receiving circuit for receiving a reverse digital message from the power device via the power wiring.

2. The controller of claim 1, wherein a controller voltage is generated across the reverse receiving circuit, the control circuit operable to receive a bit of the reverse digital message by monitoring the magnitude of the controller voltage prior to rendering the controllably conductive device conductive during a half-cycle of the AC power source.

3. The controller of claim 2, wherein the reverse digital message comprises a number of sequential data patterns, the control circuit operable to render the controllably conductive device conductive to generate a first timing edge at a predetermined reference edge time during a first half-cycle of each data pattern of the reverse digital message, and to render the controllably conductive device at a second time during a second half-cycle of each data pattern of the reverse digital message, such that a window time period exists before the second time in the second half-cycle, the control circuit operable to monitor the magnitude of the controller voltage during the window time period to receive the bit of the reverse digital message.

4. The controller of claim 3, wherein the window time period begins approximately a half-cycle time period after the predetermined reference edge time during the first half-cycle.

5. The controller of claim 3, wherein the controller is operable to transmit a continuation pattern before the power device has transmitted the total number of bits of the reverse digital message.

6. The controller of claim 2, wherein the control circuit operable to receive the bit of the reverse digital message by determining whether the magnitude of the controller voltage is either greater than or less than a threshold voltage immediately prior to rendering the controllably conductive device conductive during the half-cycle of the AC power source.

7. The controller of claim 1, further comprising:

a current path in parallel with the controllably conductive device and operable to conductive current through the power device when the controllably conductive device is non-conductive, such that the magnitude of the phase-control voltage is approximately zero volts when the controllably conductive device is non-conductive.

8. The controller of claim 1, wherein the forward digital message includes a query and the reverse digital message includes an answer to the query from the forward digital message.

9. The controller of claim 1, wherein the reverse digital message is split up into a number of packets, the control circuit operable to transmit a continuation pattern between the packets.

10. The controller of claim 9, wherein the controller is operable to transmit a start pattern to begin transmitting a new forward digital message rather than transmitting the continuation pattern after one of the packets of the reverse digital message.

11. The controller of claim 1, wherein the reverse digital message includes feedback information from the power device.

12. The controller of claim 11, wherein the control circuit is operable to transmit the feedback information to an external device.

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

14. The controller of claim 1, further comprising:

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

15. 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 the desired lighting intensity when operating in the dimmer mode, the control circuit operable to transmit a forward digital message by encoding digital information for controlling the intensity of the lighting load in the timing edges of the phase-control voltage when operating in the digital communication mode.