Ground leakage power supply for dimming applications

• US 10,505,457 B2
• Filed: 11/06/2017
• Issued: 12/10/2019
• Est. Priority Date: 11/26/2014
• Status: Active Grant

• Current Assignee: Leviton Manufacturing Company Incorporated
• Original Assignee: Leviton Manufacturing Company Incorporated
• Inventors: Papismedov, Levan, Lombardi, Alfred, Ostrovsky, Michael, Keser, Ozgur
• Primary Examiner(s): Fureman, Jared
• Assistant Examiner(s): Yeshaw, Esayas G
• Application Number:
  US15/804,614
• Publication Number:
  US 20180062524A1
• Time in Patent Office: 764 Days
• CPC Class Codes: H02M 1/0006 Arrangements for supplying an adequate voltage to the control circuit of converters
• CPC Class Codes: H02M 1/0032 Control circuits allowing low power mode operation, e.g. in standby mode
• CPC Class Codes: H02M 1/083 for the ignition at the zero crossing of the voltage or the current
• CPC Class Codes: H02M 3/33507 with automatic control of the output voltage or current, e.g. flyback converters H02M3/33561, H02M3/33569 take precedence
• CPC Class Codes: H02M 5/2573 with control circuit
• CPC Class Codes: Y02B 70/10 Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes

Abstract

A dimmer is provided for controlling power to a load, the dimmer having a ground leakage power supply deriving power from a connection of the dimmer to ground. The power supply may be a switching-mode power supply that can be the sole or primary power supply to power operation of the dimmer, including operation of the controller.

Claims

1. A dimmer comprising:

a power switch coupled between a phase input terminal of the dimmer and a load output terminal of the dimmer; and

a controller configured to perform controlling the power switch such that power to a load is selectively controlled, the controlling comprising;

providing to the power switch a pulse width modulation signal comprising a plurality of pulses, each pulse of the plurality of pulses having a duration of 8-12 microseconds.

2. The dimmer of claim 1, wherein the providing provides the pulse width modulation signal starting at or prior to a determined firing angle of a half-cycle of an AC power source to which the phase input terminal is configured to couple, and continuing for a remainder of the half-cycle.

3. The dimmer of claim 2, wherein the providing provides the plurality of pulses to have a duration therebetween that is configured to avoid unlatching of the power switch during provision of the pulse width modulation signal to the power switch during the remainder of the half-cycle.

4. The dimmer of claim 1, wherein the providing provides the plurality of pulses to have a duration therebetween of 8-12 microseconds.

5. The dimmer of claim 4, wherein the power switch comprises a Triode for Alternating Current.

6. The dimmer of claim 4, wherein the providing provides the pulse width modulation signal to have a duty-cycle of 50%.

7. The dimmer of claim 1, wherein the providing provides each pulse of the plurality of pulses to have a duration of 10 microseconds and provides the plurality of pulses to have a duration therebetween of 8-12 microseconds.

8. The dimmer of claim 7, wherein the providing provides the plurality of pulses to have a duration therebetween of 10 microseconds.

9. A ground leakage power supply comprising:

input power conversion circuitry configured to receive an AC voltage, the input power conversion circuitry comprising an AC/DC rectifier and a voltage doubler;

input filter circuitry;

high voltage switching circuitry configured to perform step-down switching mode flyback topology; and

an output circuit configured to generate an output voltage, the output circuit comprising an output filter, output rectifier, and feedback control circuit;

wherein the feedback control circuit is in communication with the high voltage switching circuitry to regulate the output voltage.

10. The ground leakage power supply of claim 9, wherein the input filter circuitry is in communication with the input power conversion circuitry and is configured to perform filtration on a DC voltage input from the input power conversion circuitry.

11. The ground leakage power supply of claim 10, wherein the high voltage switching circuitry is in communication with the input filter circuitry and is configured to perform a step-down conversion of filtered DC voltage, of a first voltage level, input from the input filter, to a second voltage, of a second voltage level.

12. The ground leakage power supply of claim 9, wherein the output circuit is further configured to perform output current limiting of the output voltage.

13. The ground leakage power supply of claim 12, wherein the output circuit is in communication with a switching controller to which the output voltage is provided.

14. The ground leakage power supply of claim 9, wherein the regulating the output voltage comprises regulating the output voltage to achieve an output voltage of +5 volts.

15. The ground leakage power supply of claim 9, further comprising a linear regulator circuit having quiescent current configured for noiseless linear output voltage.

16. The ground leakage power supply of claim 9, further comprising an input current limit circuitry configured to limit input current of the ground leakage power supply to below 500 microamperes.

17. A ground leakage power supply comprising:

a first one or more components configured to rectify and amplify an input voltage to the ground leakage power supply;

a second one or more components configured to perform input filtration on the input voltage;

a third one or more components configured to perform step-down conversion of the input voltage from a first voltage to a second voltage, the first voltage being a higher voltage than the second voltage;

a fourth one or more components configured to rectify and filter the input voltage converted to the second voltage, to provide an output voltage;

a fifth one or more components configured to provide feedback control of the output voltage, the feedback control regulating the output voltage.

18. The ground leakage power supply of claim 17, wherein the third one or more components implement a flyback switch mode topology for the step-down conversion.

19. The ground leakage power supply of claim 17, wherein the fourth one or more components is further configured to perform output current limiting.

20. The ground leakage power supply of claim 17, wherein the regulating the output voltage comprises regulating the output voltage to achieve an output voltage of +5 volts.