Monotonic pre-bias start-up of a DC-DC converter
The power conversion module includes a power converter coupled to provide a DC output voltage from an input voltage source. The power converter may have primary and secondary stages, and the power converter may also provide a DC output voltage that is electrically isolated from the input voltage source. Additionally, the power conversion module also includes a voltage controller configured to measure a pre-bias value of the output voltage prior to start-up of the power converter and provide a start-up control signal, wherein the start-up control signal corresponds to an initial output voltage that is greater than the pre-bias value of the output voltage. The initial output voltage includes a start-up voltage margin above the pre-bias value and is maintained for a margin hold time. A method of operating a power conversion module is also provided.
1. A power conversion module, comprising:
a power converter coupled to provide a DC output voltage from an input voltage source; and
a voltage controller configured to measure a pre-bias value of the output voltage prior to start-up of the power converter and provide a start-up control signal, wherein the start-up control signal corresponds to an initial output voltage that is greater than the pre-bias value of the output voltage by a start-up voltage margin, wherein the start-up voltage margin is limited by an output current capability of the power converter.
2. The power conversion module as recited in claim 1 wherein the initial output voltage is maintained for a period of time after start-up of the power converter.
3. The power conversion module as recited in claim 1 wherein the voltage controller is included as at least a portion of a digital controller.
4. The power conversion module as recited in claim 1 wherein the voltage controller has access to a database of applicable start-up voltage margins corresponding to pre-bias values and set-point voltages.
5. The power conversion module as recited in claim 1 wherein at least a portion of the voltage controller is embodied as a software program.
6. The power conversion module as recited in claim 1 further comprising a compensator limiter configured to control the start-up control signal based on maintaining a smooth transition from a pre-bias operation to a set point operation.
7. The power conversion module as recited in claim 1 further comprising a second power converter, wherein as output voltage of the second power converter sets the pre-bias value for the power converter.
8. The power conversion module as recited in claim 6 wherein the compensator limiter is included as at least a portion of a digital controller.
9. The power conversion module as recited in claim 6 wherein at least a portion of the compensator limiter is embodied as a software program.
10. The power conversion module as recited in claim 6 wherein the compensator limiter provides upper and lower limits to the start-up control signal that diverge at a specified rate of change.
11. The compensation limiter as recited in claim 10 wherein the rate of change is adaptive to the pre-bias value of the output voltage.
12. The compensation limiter as recited in claim 10 wherein the rate of change is adaptive to an output voltage droop.
13. A method of operating a power conversion module, comprising:
measuring a pre-bias value of an output voltage prior to start-up of a power converter;
calculating a start-up control signal, wherein the start-up control signal corresponds to an initial output voltage that is greater than the pre-bias value of the output voltage, and wherein calculating the start-up control signal includes employing a database of applicable start-up voltage margins corresponding to pre-bias values and set-point voltages; and
applying the initial output voltage at start-up of the power converter.
14. The method as recited in claim 13 wherein calculating the start-up control signal includes the pre-bias value of the output voltage and a start-up voltage margin.
15. The method as recited in claim 13 wherein the initial output voltage is maintained for a period of time after start-up of the power converter.
16. The method as recited in claim 13 wherein calculating the start-up control signal includes employing at least a portion of a digital controller.
17. The method as recited in claim 13 wherein calculating the start-up control signal includes employing at least a portion of a software program.
18. The method as recited in claim 13 further comprising controlling the start-up control signal based on maintaining a smooth transition from a pre-bias operation to a set point operation.
19. The method as recited in claim 13 further comprising electrically coupling a second power converter to the power converter, wherein as output voltage of the second power converter sets the pre-bias value for the power converter.
20. The method as recited in claim 14 wherein a magnitude of the start-up voltage margin is limited by an output current capability of the power converter.
21. The method as recited in claim 18 wherein controlling the start-up control signal includes monitoring an output current of the power converter.
22. The method as recited in claim 18 wherein controlling the start-up control signal includes employing at least a portion of a software program.
23. The method as recited in claim 18 wherein upper and lower limiting of the start-up control signal diverges at a specified rate of change.
24. The method as recited in claim 23 wherein the rate of change is adaptive to the pre-bias value of the output voltage.
25. The method as recited in claim 23 wherein the rate of change is adaptive to an output voltage droop.