Temperature control using a sensor network

• US 20060214014A1
• Filed: 03/25/2005
• Published: 09/28/2006
• Est. Priority Date: 03/25/2005
• Status: Active Grant

• Current Assignee: Hewlett Packard Enterprise Development LP (Hewlett-Packard Enterprise Company)
• Original Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Inventors: Sharma, Ratnesh K., Bash, Cullen E., Patel, Chandrakant D.
• Granted Patent: US 7,640,760 B2
• Time in Patent Office: Days
• US Class Current: 236/1.B
• CPC Class Codes: F24F 11/30 for purposes related to the operation of the system, e.g. for safety or monitoring
• CPC Class Codes: F24F 11/63 Electronic processing
• CPC Class Codes: F24F 2110/10 Temperature
• CPC Class Codes: G05D 23/1931 to control the temperature of one space
• CPC Class Codes: H05K 7/20745 within rooms for removing heat from cabinets, e.g. by air conditioning device
• CPC Class Codes: H05K 7/20836 Thermal management, e.g. server temperature control

Abstract

In a method for controlling temperature using a sensor network, the sensors of the sensor network are commissioned and one of a plurality of control schemes for operating a primary actuator configured to vary temperatures of the sensors based upon energy utilization requirements of the plurality of control schemes is selected. In addition, the selected one of the plurality of control schemes is implemented to vary the temperatures detected by the sensors.

Claims

1. A method for controlling temperature using a sensor network, said method comprising:

commissioning the sensors of the sensor network;

selecting one of a plurality of control schemes for operating a primary actuator configured to vary temperatures of the sensors based upon energy utilization requirements of the plurality of control schemes; and

implementing the selected one of the plurality of control schemes to vary the temperatures detected by the sensors.

2. The method according to claim 1, wherein the primary actuator comprises secondary actuators, said secondary actuators comprising a device for controlling supply airflow volume and a device for controlling supply airflow temperature, wherein the plurality of control schemes comprises various schemes for controlling the secondary actuators, and wherein the step of selecting one of the plurality of control schemes further comprises selecting the control scheme requiring the least amount of energy utilization.

3. The method according to claim 1, wherein the step of commissioning the plurality of sensors further comprises assigning the sensors to at least one primary actuator family, the method further comprising:

choosing a control sensor of the sensors, wherein the step of choosing a control sensor comprises choosing as the control sensor, the sensor having the highest positive temperature difference from a setpoint temperature, and if none of the sensors have a positive temperature difference, then choosing as the control sensor the sensor having the largest negative difference from the setpoint temperature.

4. The method according to claim 3, further comprising:

determining a level of difference between a measured temperature and a predefined temperature of the control sensor; and

transmitting an error signal corresponding to the difference.

5. The method according to claim 4, wherein the step of choosing the control sensor further comprises choosing a control sensor in each primary actuator family, and wherein the step of determining a level of difference further comprises determining a level of difference between a measured temperature and a predefined temperature of the control sensors in each primary actuator family and wherein the step of transmitting an error signal further comprises transmitting an error signal corresponding to each of the determined difference levels.

6. The method according to claim 5, wherein the step of selecting one of the plurality of control schemes further comprises selecting one of the plurality of control schemes for each primary actuator family having a chosen control sensor that transmitted an error signal.

7. The method according to claim 6, wherein a primary actuator of the at least one primary actuator family comprises secondary actuators, said secondary actuators comprising a device for controlling supply airflow volume and a device for controlling supply airflow temperature, wherein the plurality of control schemes further comprises schemes for controlling the secondary actuators according to correlations between the supply airflow volume, the supply airflow temperature, and an output of a proportional, integral, derivative (PID) control system, and wherein the step of implementing the selected control scheme further comprises varying at least one of the supply airflow volume, the supply airflow temperature, and the PID control system output according to the correlation corresponding to the selected control scheme.

8. The method according to claim 7, wherein the step of implementing the selected control scheme further comprises manipulating the secondary actuators to have supply airflow volume and supply airflow temperature setpoints that correspond to a first PID control system output level for the selected control scheme.

9. The method according to claim 6, wherein the step of commissioning further comprises assigning a plurality of primary actuator families into at least one zone, and wherein the step of choosing the control sensor further comprises choosing the sensor having the highest positive temperature difference from a setpoint temperature for each zone, and if none of the sensors have a positive temperature difference, then choosing as the control sensor the sensor having the largest negative difference from the setpoint temperature for each zone.

10. The method according to claim 9, wherein the step of implementing the selected control scheme further comprises manipulating the secondary actuators of the primary actuators in each zone to have supply airflow volume setpoints that correspond to a PID control system output level for the control scheme selected for the primary actuator family to which the control sensor belongs and manipulating the secondary actuators of the primary actuators in each zone to have supply airflow temperature setpoints that correspond to respective PID control system output levels for the control schemes selected for each primary actuator family in each zone.

11. The method according to claim 6, wherein the plurality of control schemes further comprises:

a first control scheme that includes a direct linkage between the supply airflow volume setpoint and the supply airflow temperature setpoint, such that the supply airflow volume setpoint increases substantially linearly and the supply airflow temperature decreases substantially linearly as the PID control system output increases;

a second control scheme that includes holding the supply airflow volume setpoint at a substantially constant minimum level and decreasing the supply airflow temperature setpoint substantially linearly until the PID control system output reaches a predefined value, and following arrival at the predefined value, increasing the supply airflow volume setpoint substantially linearly and holding the supply airflow temperature setpoint at a substantially constant minimum temperature level as the PID control system output increases;

a third control scheme that includes increasing the supply airflow volume substantially linearly from the minimum level and holding the supply airflow temperature at a substantially constant maximum temperature level until the PID control system output reaches the predefined value, and following arrival at the predefined value, holding the supply airflow volume setpoint at a substantially constant maximum level and decreasing the supply airflow temperature setpoint substantially linearly as the PID control system output increases; and

a fourth control scheme that includes a sliding window of VFD setpoints based upon SAT setpoints, wherein the window of VFD setpoints comprises minimum VFD setpoints and maximum VFD setpoints that respectively correspond to the SAT setpoints.

12. A system for controlling environmental conditions at a plurality of sensor locations, said system comprising:

a plurality of primary actuators configured to vary conditions detected by the sensors;

a controller configured to implement at least one algorithm configured to;

assign the sensors to one or more primary actuator families according to correlations between the sensors and the plurality of primary actuators;

choose a control sensor;

select a control scheme to operate the plurality of primary actuators based upon the energy utilization required by the primary actuators in maintaining the temperature of the control sensor either below a predefined maximum temperature or above a predefined minimum temperature; and

implement the selected control scheme in response to the control sensor having a temperature above the predefined maximum temperature.

13. The system according to claim 12, wherein the control sensor comprises one of the sensor in a primary actuator family having the highest positive temperature difference from a setpoint temperature and if none of the sensors have a positive temperature difference, the sensor in a primary actuator family having the largest negative difference from the setpoint temperature.

14. The system according to claim 12, wherein each of the primary actuators comprises secondary actuators, said secondary actuators comprising:

a device for controlling supply airflow volume; and

a device for controlling supply airflow temperature, wherein the controller is configured to implement the selected control scheme by manipulating one or both of the supply airflow volume and the supply airflow temperature according to the selected control scheme.

15. The system according to claim 14, wherein the plurality of control schemes comprise schemes for manipulating the secondary actuators of each primary actuator according to correlations between the supply airflow volume, the supply airflow temperature, and an output of a proportional, integral, derivative (PID) control system.

16. The system according to claim 15, wherein the controller is further configured to implement algorithms for manipulating the secondary actuators to operate at a supply airflow volume setpoint and a supply airflow temperature setpoint that correspond to a first PID control system output level for the selected control scheme.

17. The system according to claim 15, wherein the controller is further configured to implement algorithms for assigning the primary actuators into at least one zone and for choosing as a control sensor for each zone, the sensor having the highest positive temperature difference from a setpoint temperature, and if none of the sensors have a positive temperature difference, the sensor having the largest negative difference from the setpoint temperature.

18. The system according to claim 17, wherein the controller is further configured to implement algorithms for manipulating the secondary actuators of the primary actuators in each zone to operate at a supply airflow volume setpoint that corresponds to a PID control system output level for the control scheme selected for the primary actuator family to which the control sensor belongs and for manipulating the secondary actuators of the primary actuators in each zone to have supply airflow temperature setpoints that correspond to respective PID control system output levels for the control schemes selected for each primary actuator family in each zone.

19. The system according to claim 15, wherein control schemes further comprise:

a first control scheme that includes a direct linkage between the supply airflow volume setpoint and the supply airflow temperature setpoint, such that the supply airflow volume setpoint increases substantially linearly and the supply airflow temperature decreases substantially linearly as the PID control system output increases;

a second control scheme that includes holding the supply airflow volume setpoint at a substantially constant minimum level and decreasing the supply airflow temperature setpoint substantially linearly until the PID control system output reaches a predefined value, and following arrival at the predefined value, increasing the supply airflow volume setpoint substantially linearly and holding the supply airflow temperature setpoint at a substantially constant minimum temperature level as the PID control system output increases;

a third control scheme that includes increasing the supply airflow volume substantially linearly from the minimum level and holding the supply airflow temperature at a substantially constant maximum temperature level until the PID control system output reaches the predefined value, and following arrival at the predefined value, holding the supply airflow volume setpoint at a substantially constant maximum level and decreasing the supply airflow temperature setpoint substantially linearly as the PID control system output increases; and

a fourth control scheme that includes a sliding window of VFD setpoints based upon SAT setpoints, wherein the window of VFD setpoints comprises minimum VFD setpoints and maximum VFD setpoints that respectively correspond to the SAT setpoints.

20. A system comprising:

means for sensing conditions at a plurality of locations;

means for actuating, wherein the means for actuating is configured to vary conditions detected by the means for sensing;

means for commissioning sensors;

means for selecting a control scheme to operate the means for actuating; and

means for manipulating the means for actuating according to the control scheme selected by the means for selecting.

21. A computer readable storage medium on which is embedded one or more computer programs, said one or more computer programs implementing a method for controlling temperature using a sensor network, said one or more computer programs comprising a set of instructions for:

assigning the sensors of the sensor network to at least one primary actuator family;

choosing a control sensor;

selecting one of a plurality of control schemes for operating a primary actuator configured to maintain the temperature of the control sensor below a predetermined maximum temperature, wherein the control scheme selection is based upon energy utilization requirements of the plurality of control schemes; and

implementing the selected one of the plurality of control schemes to vary the temperatures detected by the sensors.