High efficiency power converter

• US 9,143,042 B2
• Filed: 07/22/2013
• Issued: 09/22/2015
• Est. Priority Date: 01/24/1997
• Status: Expired due to Fees

• Current Assignee: SynQor Incorporated
• Original Assignee: SynQor Incorporated
• Inventors: Schlecht, Martin F.
• Primary Examiner(s): Pham, Emily P
• Application Number:
  US13/947,893
• Publication Number:
  US 20140085939A1
• Time in Patent Office: 792 Days
• Field of Search: 363/16, 363/20, 363/21.06, 363/95, 363/97, 363/123, 363/127, 363/131
• US Class Current: 1/1
• CPC Class Codes: H02M 1/007 Plural converter units in cascade push-pull DC/DC converters with pre-regulator H02M3/3374; DC-AC converters following a DC-DC stage including a high frequency transformer H02M7/4807; DC-AC converters following a DC-DC conversion stage generating periodically varying voltages H02M7/4826
• CPC Class Codes: H02M 3/335 using semiconductor devices only
• CPC Class Codes: H02M 3/33546 with automatic control of the output voltage or current H02M3/33561 takes precedence
• CPC Class Codes: H02M 3/33553 with galvanic isolation between input and output of both the power stage and the feedback loop
• CPC Class Codes: H02M 3/33592 having a synchronous rectifier circuit or a synchronous freewheeling circuit at the secondary side of an isolation transformer
• CPC Class Codes: H02M 3/3372 of the parallel type
• CPC Class Codes: H02M 3/3374 with preregulator, e.g. current injected push-pull
• 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 power converter nearly losslessly delivers energy and recovers energy from capacitors associated with controlled rectifiers in a secondary winding circuit, each controlled rectifier having a parallel uncontrolled rectifier. First and second primary switches in series with first and second primary windings, respectively, are turned on for a fixed duty cycle, each for approximately one half of the switching cycle. Switched transition times are short relative to the on-state and off-state times of the controlled rectifiers. The control inputs to the controlled rectifiers are cross-coupled from opposite secondary transformer windings.

Claims

1. A DC-DC power converter system providing plural regulated DC outputs, comprising:

a DC input having a DC input voltage;

an isolating converter comprising;

a primary transformer winding circuit having at least one primary winding that receives power from the DC input; and

a secondary transformer winding circuit having at least one secondary winding coupled to the at least one primary winding and having plural controlled rectifiers, each of the plural controlled rectifiers having a parallel uncontrolled rectifier and being in circuit with at least one secondary winding, to provide an isolated DC output that varies by more than a few percent as the input voltage varies over its design range, the at least one primary winding having a voltage waveform with transition times that are short relative to on-state and off-state times of the plural controlled rectifiers; and

plural non-isolating switching regulators, each of the plural non-isolating switching regulators receiving power from the isolated DC output of the isolating converter and providing one of the plural regulated DC outputs having a regulated voltage.

2. A power converter system as claimed in claim 1 wherein the switching regulators are down converters.

3. A power converter system as claimed in claim 1 wherein signals controlling the controlled rectifiers are provided by the at least one secondary winding.

4. A power converter system as claimed in claim 1 wherein the isolation converter is a step down converter.

5. A power converter system as claimed in claim 1 wherein the DC input provides a voltage within the range of 36 to 75 volts.

6. A power converter system as claimed in claim 1 wherein the isolated DC output of the isolating converter is about 12 volts.

7. A power converter system as claimed in claim 1 wherein each regulated voltage of each of the regulated DC outputs is of a voltage level to drive logic circuitry.

8. A power converter system as claimed in claim 7 wherein the DC input provides a voltage within the range of 36 to 75 volts.

9. A power converter system as claimed in claim 8 wherein the isolated DC output of the isolating converter is about 12 volts.

10. A power converter system as claimed in claim 7 wherein the isolated DC output of the isolating converter is about 12 volts.

11. A power converter system as claimed in claim 1 wherein the isolated DC output drops with increasing current flow through the isolating converter.

12. A power converter system as claimed in claim 1 wherein the at least one primary winding has a voltage waveform with a fixed duty cycle.

13. A power converter system as claimed in claim 12 wherein the DC input provides a voltage within the range of 36 to 75 volts.

14. A power converter system as claimed in claim 13 wherein the isolated DC output of the isolating converter is about 12 volts.

15. A power converter system as claimed in claim 12 wherein the isolated DC output of the isolating converter is about 12 volts.

16. A power converter system as claimed in claim 1 wherein the isolating converter does not regulate the isolated DC output.

17. A DC-DC power converter system providing plural regulated DC outputs, comprising:

a DC input;

an isolating converter comprising;

a primary transformer winding circuit having at least one primary winding that receives power from the DC input; and

a secondary transformer winding circuit having at least one secondary winding coupled to the at least one primary winding and having plural controlled rectifiers, each of the plural controlled rectifiers having a parallel uncontrolled rectifier and being in circuit with at least one secondary winding, to provide an isolated DC output, the at least one primary winding having a voltage waveform with transition times that are short relative to on-state and off-state times of the plural controlled rectifiers and with a fixed duty cycle when the isolating converter is non-regulating; and

plural non-isolating switching regulators, each of the plural non-isolating switching regulators receiving power from the isolated DC output of the isolating converter and providing one of the plural regulated DC outputs having a regulated voltage.

18. A power converter system as claimed in claim 17 wherein each regulated voltage of each of the regulated DC outputs is of a voltage level to drive logic circuitry.

19. A power converter system as claimed in claim 18 wherein the DC input provides a voltage within the range of 36 to 75 volts.

20. A power converter system as claimed in claim 19 wherein the isolated DC output of the isolating converter is about 12 volts.

21. A method of providing plural regulated DC outputs, comprising:

from a DC input having a DC input voltage, providing an isolated DC output that varies by more than a few percent as the DC input voltage varies over its design range by applying power from the DC input through a primary transformer winding circuit, having at least one primary winding, and a secondary transformer winding circuit, having at least one secondary winding coupled to the at least one primary winding and having plural controlled rectifiers, each of the plural controlled rectifiers having a parallel uncontrolled rectifier and being in circuit with the at least one secondary winding, the at least one primary winding having a voltage waveform with transition times that are short relative to on-state and off-state times of the plural controlled rectifiers; and

applying power from the isolated DC output to plural non-isolating switching regulators, each of the plural non-isolating switching regulators providing one of the plural regulated DC outputs having a regulated voltage.

22. A method of providing plural regulated DC outputs, comprising:

from a DC input, providing an isolated DC output by applying power from the DC input through a primary transformer winding circuit, having at least one primary winding, and a secondary transformer winding circuit, having at least one secondary winding coupled to the at least one primary winding and having plural controlled rectifiers, each of the plural controlled rectifiers having a parallel uncontrolled rectifier and being in circuit with the at least one secondary winding, the at least one primary winding having a voltage waveform with transition times that are short relative to on-state and off-state times of the plural controlled rectifiers and with a fixed duty cycle when the isolated DC output is non-regulated; and

applying power from the isolated DC output to plural non-isolating switching regulators, each of the plural non-isolating switching regulators providing one of the plural regulated DC outputs having a regulated voltage.