Phase-controlled AC-DC power converter

• US 20020109487A1
• Filed: 01/10/2002
• Published: 08/15/2002
• Est. Priority Date: 01/10/2001
• Status: Active Grant

• Current Assignee: Dialog Semiconductor Incorporated (Renesas Electronics Corporation)
• Original Assignee: iWatt, Inc. (Renesas Electronics Corporation)
• Inventors: Wong, Dickson T., Telefus, Mark D.
• Granted Patent: US 6,707,285 B2
• Time in Patent Office: Days
• US Class Current: 323/239
• CPC Class Codes: H02M 1/10 Arrangements incorporating converting means for enabling loads to be operated at will from different kinds of power supplies, e.g. from ac or dc
• CPC Class Codes: H02M 3/285 Single converters with a plurality of output stages connected in parallel parallel operation of a plurality of converters in dc distribution networks H02J1/10
• CPC Class Codes: H02M 7/23 arranged for operation in parallel H02M7/2176 takes precedence

Abstract

An AC to DC power converter, comprising an input, an output, a plurality of pass elements connected in parallel between the input and output, and a controller for switching ON a subset of the plurality of pass elements. The controller sets an ON time for at least one pass element in the subset based on a load at the output and a phase angle of an input voltage at the input. The input voltage may comprise a single or multiphase signal. The number of pass elements in the subset is based on the load. In one embodiment, each pass element comprising a pair of series-connected field effect transistors coupled source to source and operated in fully enhanced mode.

Claims

1. A power converter, comprising:

an input;

an output;

a pass element connected between the input and output; and

a controller for switching the pass element ON and OFF at phase angles of an AC input voltage received at the input in order to regulate a DC output voltage at the output.

2. The power converter of claim 1, the controller switching the pass element ON at a first selected phase angle, and OFF at a second selected phase angle, the first and second phase angles determined by the controller based on the output voltage.

3. The power converter of claim 1, the pass element comprising a pair of seriest5 connected field effect transistors coupled source to source and operated in fully enhanced mode.

4. The power converter of claim 1, comprising a plurality of pass elements connected between the input and output, the controller switching respective pass elements ON and OFF independent of each other.

5. The power converter of claim 4, wherein the number of pass elements switched ON by the controller is based at least in part on the output voltage.

6. The power converter of claim 4, the controller determining phase angles for switching at least two of the respective pass elements ON and OFF based at least in part on balancing current through the respective pass elements.

7. The power converter of claim 4, each pass element comprising a pair of series-connected field effect transistors coupled source to source and operated in fully enhanced mode.

8. The power converter of claim 1, wherein the input voltage comprises a single phase signal.

9. The power converter of claim 1, wherein the input voltage comprises a multiphase signal.

10. A method of regulating power using an AC to DC converter, the power converter comprising an input, an output, and a pass element connected between the input and output, the method comprising:

switching the pass element ON and OFF at phase angles of an AC input voltage received at the input in order to regulate a DC output voltage at the output.

11. The method of claim 10, wherein the pass element is switched ON at a first selected phase angle, and switched OFF at a second selected phase angle, the first and second phase angles determined based on the output voltage.

12. The method of claim 10, the pass element comprising a pair of series-connected field effect transistors coupled source to source and operated in fully enhanced mode.

13. The method of claim 10, the converter comprising a plurality of pass elements connected between the input and output, further comprising switching respective pass elements ON and OFF independent of each other.

14. The method of claim 13, wherein the number of pass elements switched ON is based at least in part on the output voltage.

15. The method of claim 13, wherein phase angles for switching at least two of the respective pass elements ON and OFF is based at least in part on balancing current through the respective pass elements.

16. The method of claim 13, each pass element comprising a pair of series-connected field effect transistors coupled source to source and operated in fully enhanced mode.

17. The method of claim 10, wherein the input voltage comprises a single phase signal.

18. The method of claim 10, wherein the input voltage comprises a multi-phase signal.