Driver device and driving method for driving a load, in particular a LED unit comprising one or more LEDs

• US 20150002040A1
• Filed: 01/18/2013
• Published: 01/01/2015
• Est. Priority Date: 02/01/2012
• Status: Active Grant

• Current Assignee: Signify Holding B.V. (Signify N.V.)
• Original Assignee: Koninklijke Philips N.V.
• Inventors: Malyna, Dmytro Viktorovych, De Bruycker, Patrick Alouisius Martina
• Granted Patent: US 9,743,467 B2
• Time in Patent Office: Days
• US Class Current: 315/201
• CPC Class Codes: H05B 45/315 Reverse phase-control circuits
• CPC Class Codes: H05B 45/3575 by means of dummy loads or bleeder circuits, e.g. for dimmers
• CPC Class Codes: H05B 45/37 Converter circuits

Abstract

The present invention relates to a driver device (60) for driving a load (12), in particular an LED unit comprising one or more LEDs, said driver device comprising input terminals (28, 30) for receiving an input voltage (V12) from an external power supply (16), output terminals for providing an output voltage to the load (12) for driving the load (12), a converter unit (34) for converting the input voltage (VI 2) to a converted voltage (VI 4) and for providing the converted voltage (VI 4) to internal connection elements (63, 64) of the driver device (60), a signal control device (62) for applying an electrical signal (I) to at least one of the connection elements (63, 64), and a detection circuit for detecting a phase angle of the input voltage (VI 2) by measuring a voltage drop of the converted voltage (VI 4) caused by the electrical signal (I).

Claims

1. Driver device for driving a load, in particular an LED unit comprising one or more LEDs, said driver device comprising:

input terminals for receiving an input voltage from an external power supply,

output terminals for providing an output voltage to the load for driving the load,

a converter unit for converting the input voltage to a converted voltage and for providing the converted voltage to internal connection elements of the driver device,

a signal control device for applying an electrical signal (I) to at least one of the connection elements, and

a detection circuit for detecting a phase angle of the input voltage by measuring a voltage dip of the converted voltage caused by the electrical signal (I).

2. Driver device as claimed in claim 1, wherein the electrical signal (I) is an electrical current (I) drawn from or provided to the connection elements.

3. Driver device as claimed in claim 1, wherein the signal control device comprises an electrical storage element for storing electrical energy and a controllable switch for electrically connecting the electrical storage element to at least one of the connection elements.

4. Driver device as claimed in claim 1, wherein the signal control device further comprises a charge control element connected to the electrical storage element for controlling the electrical charge stored in the electrical storage element.

5. Driver device as claimed in claim 3, wherein the electrical storage element is a charge capacitor.

6. Driver device as claimed in claim 1, wherein the signal control device comprises a current path including a resistor and a controllable switch for connecting the connection elements to each other.

7. Driver device as claimed in claim 1, wherein the signal control device comprises a controllable current source for providing the electrical signal (I).

8. Driver device as claimed in claim 1, wherein the converter unit comprises a rectifier unit connected to the input terminals for rectifying the input voltage to a unipolar voltage provided to the connection elements.

9. Driver device as claimed in claim 1, wherein the detection circuit comprises a differentiator circuit for measuring the voltage dip of the converted voltage.

10. Driver device as claimed in claim 1, wherein the signal control unit is adapted to provide the electrical signal (I) for a time interval less than 1/0 of a half-cycle of the input voltage.

11. Driver device as claimed in claim 1, wherein the input voltage is an alternating phase-cut voltage and wherein the signal control unit is adapted to apply the electrical signal (I) at different points in time within each half cycle of the input voltage to detect a phase angle of the input voltage.

15. Light apparatus comprising:

a light assembly comprising one or more light units, in particular an LED unit comprising one or more LEDs, and

a driver device as claimed in claim 11 for driving said assembly.

12. Driving method for driving a load 12, in particular an LED unit comprising one or more LEDs, said method comprising:

receiving an input voltage from an external power supply at input terminals,

converting the input voltage to a converted voltage and providing the converted voltage to internal connection elements,

applying an electrical signal (I) to at least one of the internal connection elements using a signal control unit, and

detecting a phase angle of the input voltage by detecting a voltage dip of the converted voltage caused by the electrical signal (I).

13. Driving method as claimed in claim 12, wherein the input voltage is an alternating phase-cut voltage and wherein the point in time at which the electrical signal (I) is applied is varied within each half cycle of the input voltage to detect the phase angle of the input voltage.

14. Driving method as claimed in claim 12, wherein the point in time is varied stepwise in consecutive half cycles of the input voltage to detect the phase angle of the input voltage.