Thermal management in a multi-phase power system

Patent metadata

Field	Value
Publication number	US-9639105-B2
Application number	US-201414543970-A
Country	US
Kind code	B2
Filing date	Nov 18, 2014
Priority date	Nov 18, 2014
Publication date	May 2, 2017
Grant date	May 2, 2017

Abstract

One aspect is a method that includes applying a plurality of incrementally varying voltage targets to a plurality of power phase converters operating in parallel between a source voltage rail and a load voltage rail. A phase temperature of each of the power phase converters is monitored. The phase temperature of each of the power phase converters is compared to a thermal adjustment limit. One or more of the power phase converters are adjusted to reduce an associated output current based on determining that at least one of the power phase converters exceeds the thermal adjustment limit. Power phase converter adjustments can be performed in a balanced manner such that a net sum voltage at the load voltage rail is substantially unchanged after the adjustments.

First claim

What is claimed is:

1. A system comprising:
a plurality of power phase converters operable in parallel between a source voltage rail and a load voltage rail; and
a controller operably coupled to the power phase converters and configured to perform a method comprising:
applying a plurality of incrementally varying voltage targets to the power phase converters;
monitoring a phase temperature of each of the power phase converters;
comparing the phase temperature of each of the power phase converters to a thermal adjustment limit;
adjusting one or more of the power phase converters to reduce an associated output current based on determining that at least one of the power phase converters exceeds the thermal adjustment limit;
determining a remaining thermally deliverable power for each of the power phase converters based on a summing for all of the power phase converters that are active a lesser of a phase output current limit minus a present current output or a remaining estimated current deliverable prior to a thermal shutdown;
comparing the remaining thermally deliverable power to a throttling threshold; and
outputting a throttling command to a load controller to request a load reduction based on the remaining thermally deliverable power crossing the throttling threshold.

2. The system of claim 1 , wherein adjusting one or more of the power phase converters comprises decreasing at least one of the voltage targets for the at least one of the power phase converters that exceeds the thermal adjustment limit.

3. The system of claim 2 , wherein adjusting one or more of the power phase converters comprises increasing at least one of the voltage targets to compensate for the reduction of the associated output current by the at least one of the power phase converters exceeds the thermal adjustment limit.

4. The system of claim 3 , wherein a magnitude of adjustment is determined based on a difference from a mean phase temperature of all of the power phase converters and the phase temperature of each of the one or more of the power phase converters being adjusted.

5. The system of claim 1 , wherein the controller is further configured to perform:
determining a number of power phase converters that are active; and
setting the incrementally varying voltage targets based on an expected temperature and current distribution between the power phase converters under nominal conditions as adjusted by the number of power phase converters that are active.

6. The system of claim 1 , wherein the power phase converters form a first subgroup on a point-of-load card and the system further comprises a second plurality of power phase converters that form a second subgroup on the point-of-load card between the source voltage rail and a second load voltage rail, the first and second subgroups share a common heat sink, and adjustments to the power phase converters are performed at a subgroup level to substantially balance the phase temperature across each of the first and second subgroups.

7. A computer program product comprising:
a computer readable storage medium having computer readable program code embodied therewith, the computer readable program code comprising:
computer readable program code configured for:
applying a plurality of incrementally varying voltage targets to a plurality of power phase converters operating in parallel between a source voltage rail and a load voltage rail;
monitoring a phase temperature of each of the power phase converters;
comparing the phase temperature of each of the power phase converters to a thermal adjustment limit;
adjusting one or more of the power phase converters to reduce an associated output current based on determining that at least one of the power phase converters exceeds the thermal adjustment limit;
determining a remaining thermally deliverable power for each of the power phase converters based on a summing for all of the power phase converters that are active a lesser of a phase output current limit minus a present current output or a remaining estimated current deliverable prior to a thermal shutdown;
comparing the remaining thermally deliverable power to a throttling threshold; and
outputting a throttling command to a load controller to request a load reduction based on the remaining thermally deliverable power crossing the throttling threshold.

8. The computer program product of claim 7 , wherein adjusting one or more of the power phase converters comprises decreasing at least one of the voltage targets for the at least one of the power phase converters that exceeds the thermal adjustment limit.

9. The computer program product of claim 8 , wherein adjusting one or more of the power phase converters comprises increasing at least one of the voltage targets to compensate for the reduction of the associated output current by the at least one of the power phase converters exceeds the thermal adjustment limit.

10. The computer program product of claim 9 , wherein a magnitude of adjustment is determined based on a difference from a mean phase temperature of all of the power phase converters and the phase temperature of each of the one or more of the power phase converters being adjusted.

11. The computer program product of claim 7 , wherein the computer readable program code is further configured for:
determining a number of power phase converters that are active; and
setting the incrementally varying voltage targets based on an expected temperature and current distribution between the power phase converters under nominal conditions as adjusted by the number of power phase converters that are active.

12. The computer program product of claim 7 , wherein the power phase converters form a first subgroup on a point-of-load card and a second plurality of power phase converters form a second subgroup on the point-of-load card between the source voltage rail and a second load voltage rail, the first and second subgroups share a common heat sink, and adjustments to the power phase converters are performed at a subgroup level to substantially balance the phase temperature across each of the first and second subgroups.

Assignees

• IBM

Inventors

• Goth Gary F
• Makowicki Robert P
• Shevach Steven G
• Vandeventer Allan C
• Wei Xiaojin

Classifications

• H02M2001/327

  Electricity · mapped topic

• H02M3/285

  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 title

• H02M1/32

  Means for protecting converters other than automatic disconnection · CPC title

• H02M3/156

  with automatic control of output voltage or current, e.g. switching regulators · CPC title

• G05F3/02 Primary

  Regulating voltage or current · CPC title