High efficiency power converter
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.
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.