Multiphase light fixture

Patent metadata

Field	Value
Publication number	US-10009972-B2
Application number	US-201715427252-A
Country	US
Kind code	B2
Filing date	Feb 8, 2017
Priority date	Feb 8, 2016
Publication date	Jun 26, 2018
Grant date	Jun 26, 2018

Abstract

Multiphase lighting fixtures having one or more light emitting diode (LED) light sources are provided. In one example implementation, a light fixture includes one or more light sources, such as LED light sources and a power conversion circuit. The power conversion circuit includes a phase shifting transformer for implementing a phase shift between output phases of secondary windings thereof, a multi-phase rectifier having a first rectifier and a second rectifier connected in parallel for converting a multiphase input power to a rectified output or a six-pulse configuration, a zero sequence blocking transformer for reducing harmonic distortion, an interphase transformer for further reducing harmonic distortion, and a current regulator for providing a constant DC current output to the one or more light sources. In some example implementations, the DC rectified output has a voltage ripple of less than about 7%, or less than about 3%.

First claim

What is claimed is:

1. A light fixture, comprising:
one or more light emitting diode (LED) light sources;
a power conversion circuit, the power conversion circuit configured to receive a multiphase input power comprising three or more alternating current phases and to convert the multiphase input power to a rectified output for powering the one or more LED light sources;
wherein the power conversion circuit comprises a multi-pulse, multiphase rectifier, the multi-pulse, multiphase rectifier having a first rectifier and a second rectifier coupled in parallel, the multi-pulse multiphase rectifier further having a zero sequence blocking transformer coupled to the first rectifier and the second rectifier, a phase shifting transformer having a primary winding, a first secondary winding and a second secondary winding, the first secondary winding coupled to the first rectifier, the second secondary winding coupled to the second rectifier, the multi-pulse multiphase rectifier further comprising an interphase transformer and a current regulator, wherein the current regulator is configured to receive the rectified output and provide a constant current to the one or more light emitting diode (LED) light sources.

2. The light fixture of claim 1 wherein the rectified output for powering the one or more light sources has a voltage ripple.

3. The light fixture of claim 2 , wherein the voltage ripple is less than about 7%.

4. The light fixture of claim 2 , wherein the voltage ripple is less than about 3%.

5. The light fixture of claim 2 , wherein a constant current from the current regulator is generated to power the one or more LED light sources such that the one or more LED light sources have a percent flicker of less than about 7%.

6. The light fixture of claim 2 , wherein a constant current from a current regulator is generated to power the one or more LED light sources such that the one or more LED light sources have a percent flicker of less than about 3%.

7. The light fixture of claim 1 , wherein the phase shifting transformer is configured to provide about a 30° phase shift between an output of the first secondary winding and the second secondary winding.

8. The light fixture of claim 1 , wherein the primary winding has a wye configuration, the first secondary winding has a wye configuration, and the second secondary winding has a delta configuration.

9. The light fixture of claim 1 , wherein the light fixture is a high-bay light fixture.

10. The light fixture of claim 1 , wherein the interphase transformer configured to provide a twenty-four pulse output.

Assignees

• Hubbell Inc

Inventors

• Clawson Jr Thomas N
• Weeks Jr T Warren
• Bailey Chris
• Hamilton Douglas M

Classifications

• H02M7/10 Primary

  arranged for operation in series, e.g. for multiplication of voltage · CPC title

• H05B45/10

  Controlling the intensity of the light · CPC title

• H02M7/068

  mounted on a transformer · CPC title

• H02M1/14

  Arrangements for reducing ripples from DC input or output · CPC title

• H02M7/08

  arranged for operation in parallel · CPC title