Method for estimating temperature at a critical point

• US 9,546,914 B2
• Filed: 10/31/2012
• Issued: 01/17/2017
• Est. Priority Date: 10/13/2008
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: Cox, Keith, Kapoor, Gaurav, Arnold, Vaughn
• Primary Examiner(s): Breene, John
• Assistant Examiner(s): Dinh, Lynda
• Application Number:
  US13/665,308
• Publication Number:
  US 20130060510A1
• Time in Patent Office: 1,539 Days
• Field of Search: 702/130
• US Class Current: 1/1
• CPC Class Codes: G01K 1/20 Compensating for effects of temperature changes other than those to be measured, e.g. changes in ambient temperature
• CPC Class Codes: G01K 7/42 Circuits effecting compensation of thermal inertia; Circuits for predicting the stationary value of a temperature
• CPC Class Codes: G01K 7/425 Thermal management of integrated systems
• CPC Class Codes: G01K 7/427 Temperature calculation based on spatial modeling, e.g. spatial inter- or extrapolation
• CPC Class Codes: G06F 1/206 comprising thermal management
• CPC Class Codes: G06F 1/26 Power supply means, e.g. regulation thereof for memories G11C

Abstract

Methods and apparatuses are disclosed to estimate temperature at one or more critical points in a data processing system comprising modeling a steady state temperature portion of a thermal model at the one or more critical points using regression analysis; modeling the transient temperature portion of the thermal model at the one or more critical points using a filtering algorithm; and generating a thermal model at the one or more critical points by combining the steady state temperature portion of the thermal model with the transient temperature portion of the thermal model. The thermal model may then be used to estimate an instantaneous temperature at the one or more critical points or to predict a future temperature at the one or more critical points.

Claims

1. A machine-implemented method comprising:

retrieving, by a processor of a data processing system having a housing that houses at least the processor and a memory, from the memory of the data processing system, a representation of a thermal model of a temperature of a target location on the housing of the data processing system, wherein the thermal model includes;

a first component which estimates a steady state temperature of the target location on the housing of the data processing system based on a steady state temperature behavior of a location inside of the housing, and

a second component which estimates a transient temperature of the target location on the housing of the data processing system based on a transient temperature behavior of the location inside of the housing;

receiving, by the processor, temperature data from a temperature sensor located at the location inside of the housing;

estimating, by the processor, the temperature of the target location on the housing of the data processing system based on the temperature data for the location inside of the housing using the thermal model; and

initiating a signal, by the processor, in response to the estimated temperature of the target location being at or above a predetermined temperature, wherein the signal causes a reduction in the temperature of the target location on the housing.

2. A non-transitory machine-readable medium storing executable instructions, which when executed, causes a system to perform a method comprising:

retrieving, by a processor of a data processing system having a housing that houses at least the processor and a memory, from the memory of the data processing system, a representation of a thermal model of a temperature of a target location on the housing of the data processing system, wherein the thermal model includes;

a first component which estimates a steady state temperature of the target location on the housing of the data processing system based on a steady state temperature behavior of a location inside of the housing, and

a second component which estimates a transient temperature of the target location on the housing of the data processing system based on a transient temperature behavior of the location inside of the housing;

receiving, by the processor, temperature data from a temperature sensor located at the location inside of the housing;

estimating, by the processor, the temperature of the target location on the housing of the data processing system based on the temperature data for the location inside of the housing using the thermal model; and

initiating a signal, by the processor, in response to the estimated temperature of the target location being at or above a predetermined temperature, wherein the signal causes a reduction in the temperature of the target location on the housing.

3. A data processing apparatus comprising:

at least one temperature sensor located on a data processing apparatus at a first position inside of a housing of the data processing apparatus;

a memory configured to store a representation of a thermal model for a location on the housing of the data processing apparatus at a second position which is different from the first position inside of the housing, the thermal model having a first component which estimates a steady state temperature of the second location on the housing of the data processing apparatus based on a steady state temperature behavior at the first position inside of the housing of the data processing apparatus and having a second component which estimates a transient temperature of the second location on the housing of the data processing apparatus based on a transient temperature behavior at the first position inside of the housing of the data processing apparatus;

a processor inside of the housing of the data processing apparatus, the processor coupled to the memory and to the at least one temperature sensor, the processor configured to

estimate the temperature of the second position on the housing based on the temperature data for the first location inside of the housing using the representation of the thermal model, and

initiate a signal, by the processor in response to the estimated temperature of the second position being at or above a predetermined temperature, wherein the signal causes a reduction in the temperature of the second position on the housing.

4. A method to estimate temperature of a data processing system comprising:

generating, by a processor of a data processing system, a transient temperature portion of a thermal model of a temperature of a target location on a housing that houses the processor and a memory of the data processing system, including;

filtering, by the processor, a temperature sensor at a plurality of frequencies to obtain a corresponding plurality of filtered values, wherein the temperature sensor is located at a location inside of the housing,

generating, by the processor, a set of weighted values by applying weights to each of the plurality of filtered values, and

combining, by the processor, the set of weighted values to generate the transient temperature portion of the thermal model of the temperature of the target location on the housing of the data processing system;

estimating, by the processor, the temperature of the target location on the housing of the data processing system based on temperature data from the temperature sensor at the location inside of the housing using the transient temperature portion of the thermal model; and

initiating a signal, by the processor, in response to the estimated temperature of the target location being at or above a predetermined temperature, wherein the signal causes a reduction in the temperature of the target location on the housing.

5. The method of claim 4, wherein the plurality of frequencies includes a set of three frequencies including a maximum correlation frequency, a slow moving frequency less than the maximum correlation frequency, and a fast moving frequency greater than the maximum correlation frequency.

6. The method of claim 4, further comprising generating a steady state temperature portion of the thermal model of the target location by performing a regression analysis of the target location at a steady state temperature.

7. The method of claim 6, further comprising choosing additional temperature sensors to perform the regression analysis including:

applying power to the data processing system;

monitoring thermal behavior of a plurality of temperature sensors over time; and

choosing a minimum number of the plurality of temperature sensors to perform the regression analysis.

8. The method of claim 7, wherein the minimum number of temperature sensors includes a pair of the temperature sensors having a maximum variance with respect to the target location.

9. The method of claim 6, further comprising generating the thermal model of the target location by merging the transient temperature portion of the thermal model with the steady state temperature portion of the thermal model.

10. The method of claim 9, further comprising estimating an instantaneous temperature of the target location based on the thermal model.

11. The method of claim 10, further comprising:

generating a future thermal model of the target location based on the thermal model;

predicting a future temperature of the target location based on the future thermal model; and

initiating proactive measures to reduce the temperature of the target location on the housing.

12. The method of claim 11, wherein generating the future temperature model of the target location includes modifying the weights of the set of filtered values used to generate the transient temperature portion of the thermal model.

13. A non-transitory computer-readable storage medium that provides instructions, which when executed by a computer system, cause the computer system to perform a method to estimate temperature of one or more critical points, the method comprising:

generating, by a processor of a data processing system, a transient temperature model of a temperature of a target location on a housing of the data processing system, including;

filtering, by the processor, a temperature sensor at a plurality of frequencies to obtain a corresponding plurality of filtered values, wherein the temperature sensor is located at a location inside of the housing,

generating, by the processor, a set of weighted values by applying weights to each of the plurality of filtered values, and

combining, by the processor, the set of weighted values to generate the transient temperature portion of the thermal model of the temperature of the target location on the housing of the data processing system;

estimating, by the processor, the temperature of the target location on the housing of the data processing system based on temperature data from the temperature sensor at the location inside of the housing using the transient temperature portion of the thermal model; and

initiating a signal, by the processor, in response to the estimated temperature of the target location being at or above a predetermined temperature, wherein the signal causes a reduction in the temperature of the target location on the housing.

14. The non-transitory computer-readable storage medium of claim 13, wherein the plurality of frequencies is a set of three frequencies including a maximum correlation frequency, a slow moving frequency less than the maximum correlation frequency, and a fast moving frequency greater than the maximum correlation frequency.

15. The non-transitory computer-readable storage medium of claim 13, further comprising generating a steady state temperature portion of the thermal model of the target location by performing a regression analysis of the target location.

16. The non-transitory computer-readable storage medium of claim 15, further comprising choosing additional temperature sensors to perform the regression analysis including:

applying power to the computer system;

monitoring thermal behavior of a plurality of temperature sensors over time; and

choosing a minimum number of the plurality of temperature sensors to perform the regression analysis.

17. The non-transitory computer-readable storage medium of claim 15, further comprising generating the thermal model of the target location by merging the transient temperature portion of the thermal model with the steady state temperature portion of the thermal model.

18. The non-transitory computer-readable storage medium of claim 17, further comprising estimating an instantaneous temperature of the target location based on the thermal model.

19. The non-transitory computer-readable storage medium of claim 17, further comprising:

generating a future thermal model of the target location based on the thermal model; and

predicting a future temperature of the target location based on the future thermal model.

20. The non-transitory computer-readable storage medium of claim 19, wherein generating the future thermal model of the target location includes modifying the weights of the plurality of filtered values used to generate the transient temperature portion of the thermal model.

21. A method to estimate temperature of a data processing system comprising:

generating, by a processor of a data processing system, a steady state temperature portion of a thermal model of a temperature of a target location on a housing of the data processing system using regression analysis to estimate a steady state temperature of the target location based on a steady state temperature behavior of a temperature sensor located inside of the housing of the data processing system;

generating, by the processor, a transient temperature portion of the thermal model of the temperature of the target location on the housing of the data processing system using a filtering algorithm to estimate a transient temperature of the target location based on a transient temperature behavior of the temperature sensor located inside of the housing of the data processing system;

generating, by the processor, the thermal model of the temperature of the target location on the housing of the data processing system by combining the steady state temperature portion of the thermal model with the transient temperature portion of the thermal model;

estimating, by the processor, an instantaneous temperature of the target location on the housing based on the thermal model; and

initiating a signal, by the processor, in response to the estimated temperature of the target location being at or above a predetermined temperature, wherein the signal causes a reduction in the temperature of the target location on the housing.

22. The method of claim 21, wherein the filtering algorithm comprises:

filtering at least one temperature sensor at a plurality of frequencies to obtain a corresponding plurality of filtered values;

generating a set of weighted values based on applying weights to each of the plurality of filtered values; and

combining the set of weighted values to generate the transient temperature portion of the thermal model of the target location.

23. A non-transitory computer-readable storage medium that provides instructions, which when executed by a computer system, cause the computer system to perform a method to estimate temperature of one or more critical points, the method comprising:

generating, by a processor of a data processing system, a steady state temperature portion of a thermal model of a temperature of a target location on a housing of the data processing system using regression analysis to estimate a steady state temperature of the target location based on a steady state temperature behavior of a temperature sensor located inside of the housing of the data processing system;

generating, by the processor, a transient temperature portion of the thermal model of the temperature of the target location on the housing of the data processing system using a filtering algorithm to estimate a transient temperature of the target location based on a transient temperature behavior of the temperature sensor located inside of the housing of the data processing system;

generating, by the processor, the thermal model of the temperature of the target location on the housing of the data processing system by combining the steady state temperature portion of the thermal model with the transient temperature portion of the thermal model;

estimating, by the processor, an instantaneous temperature of the target location on the housing based on the thermal model; and

initiating a signal, by the processor, in response to the estimated temperature of the target location being at or above a predetermined temperature, wherein the signal causes a reduction in the temperature of the target location on the housing.

24. The non-transitory computer readable storage medium of claim 23, wherein the filtering algorithm comprises:

filtering at least one temperature sensor at a plurality of frequencies to obtain a corresponding plurality of filtered values;

generating a set of weighted values based on applying weights to each of the plurality of filtered values; and

combining the set of weighted values to generate the transient temperature portion of the thermal model of the target location.