DYNAMIC CONVERTER TOPOLOGY

• US 20080259646A1
• Filed: 04/18/2008
• Published: 10/23/2008
• Est. Priority Date: 04/20/2007
• Status: Active Grant

• Current Assignee: Intersil Americas LLC (Renesas Electronics Corporation)
• Original Assignee: Intersil Americas LLC (Renesas Electronics Corporation)
• Inventors: MOUSSAOUI, ZAKI
• Granted Patent: US 8,085,556 B2
• Time in Patent Office: Days
• US Class Current: 363/17
• 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 3/33571 Half-bridge at primary side of an isolation transformer
• CPC Class Codes: H02M 3/33573 Full-bridge at primary side of an isolation transformer

Abstract

Methods and apparatus of dynamic topology power converters are provided. One method includes monitoring at least one variable of the power converter and based on the at least one monitored variable, using a converter topology selected between at least a full-bridge converter topology and a half-bridge converter topology to achieve an efficient operation at a then current operational load.

Claims

1. A method of operating a power converter, the method comprising:

monitoring at least one condition of the power converter; and

based on the at least one monitored condition, using a converter topology selected between at least a full-bridge converter topology and a half-bridge converter topology to achieve an efficient operation at a then current operational load.

2. The method of claim 1, further comprising:

comparing each of the monitored at least one condition with a select threshold; and

changing the converter topology when the monitored at least one condition passes the threshold.

3. The method of claim 1, wherein monitoring the at least one condition further comprises:

monitoring at least one of output current, output power, phase shift, switching frequency, hold up time and temperature.

4. The method of claim 1, wherein monitoring at least one condition of the power converter further comprises:

when running in the full-bridge converter topology, monitoring the phase shift.

5. The method of claim 1, wherein monitoring at least one condition of the power converter further comprises:

when running in the half-bridge converter topology, monitoring the switching frequency.

6. The method of claim 1, further comprising:

selectively disabling the power converters ability to switch between the at least full-bridge converter and the half-bridge converter topologies.

7. A method of operating a DC-to-DC power converter, the method comprising:

determining the efficiency of the power converter; and

when it is determined that the power converter is running below a selected efficiency, switching a converter topology of the power converter between a full-bridge converter topology and a half-bridge converter topology.

8. The method of claim 7, wherein switching from a full-bridge converter topology to a half-bridge converter topology further comprises:

from a first and second pair of switching elements, manipulating a first switching element in the second pair to remain open and a second switching element in the second pair to remain closed.

9. The method of claim 8, wherein switching from a half-bridge converter topology to a full-bridge converter topology further comprises:

allowing the first switching element in the second pair of switching elements and the second switching element in the second pair of switching elements to open and close in a usual manner for full-bridge converter operation.

10. The method of claim 7, wherein determining the efficiency of the power converter further comprises:

monitoring at least one condition related to efficiency; and

comparing each of the at least one variables to a defined threshold.

11. The method of claim 10, wherein monitoring the at least one condition further comprises:

monitoring at least one of output current, output power, phase shift, switching frequency, hold up time and temperature.

12. The method of claim 10, wherein monitoring at least one condition further comprises:

when running in the full-bridge converter topology, monitoring the phase shift.

13. The method of claim 10, wherein monitoring at least one condition further comprises:

when running in the half-bridge converter topology, monitoring the switching frequency.

14. A voltage converter circuit, the circuit comprising:

at least first and second voltage converter topologies, wherein the first voltage converter topology is a full-bridge converter topology and the second voltage converter topology is a half-bridge converter topology;

an output node; and

a controller operable to implement one of the first and second voltage converter topologies to provide an output power to the output node in response to a parameter associated with an output load.

15. The voltage converter of claim 14, wherein the at least first and second voltage converter topologies share a first and second pair of switching elements.

16. The voltage converter of claim 14, wherein the controller is further operable to manipulate the second pair of switching elements to change between the first and second voltage converter topologies.

17. The voltage converter of claim 16, wherein the controller is further operable to switch from a full-bridge converter topology to a half-bridge converter topology by manipulating a first switching element in the second pair to remain open and a second switching element in the second pair to remain closed, and switch from a half-bridge converter topology to a full-bridge converter topology by allowing the first switching element in the second pair and the second switching element in the second pair to open and close in a usual manner for full-bridge converter operation.

18. A DC-to-DC voltage converter, the converter comprising:

a first rail having a first end configured receive a signal at a first potential;

a second rail having a first end configured to receive a signal at a second potential;

an input inductor coupled to the first rail;

a first switching mechanism coupled between the first and second rail configured to control a regulated output of the converter;

a first and second pair of switching mechanisms that form a converter topology of the converter, the first and the second pair of switching elements coupled across the first and the second rail;

a transforming having a primary winding selectively coupled across the first and second rails via the first and second pair of switching mechanisms, the transformer further having at least one secondary winding coupled to a low pass filter coupled to and output node; and

a controller configured to selectively control the second pair of switching mechanisms to change the converter topology between a full-bridge converter and a half-bridge converter.

19. The converter of claim 18, further comprising:

a bridge rectifier coupled to receive the first and second potential signals, the bridge rectifier further coupled between the first and second rails; and

a power factor correction controller coupled to inductor configured to control the duty cycle of the first switching mechanism.

20. The converter of claim 18, wherein the controller is further configured to switch to a half-bridge converter by maintaining a first switch of the second pair of switching mechanisms open and maintaining a second switch in the second pair of switching mechanism closed.

21. An electronic system, the system comprising:

a varying load device having at least one power input;

a converter having at least one output coupled to the at least one power input of the varying load device;

the converter including,

at least first and second voltage converter topologies, wherein the first voltage converter topology is a full-bridge converter topology and the second voltage converter topology is a half-bridge converter topology,

an output node, and

a controller operable to implement one of the first and second voltage converter topologies to provide an output power to the output node in response to a parameter associated with an output load of the varying load device.