Error based zone controller

• US 5,318,104 A
• Filed: 09/16/1992
• Issued: 06/07/1994
• Est. Priority Date: 06/27/1991
• Status: Expired due to Term

• Current Assignee: Honeywell Incorporated (Honeywell International Inc.)
• Original Assignee: Honeywell Incorporated (Honeywell International Inc.)
• Inventors: Buchholz, Robert L., Grald, Eric W., Nelson, Lorne W., MacArthur, J. Ward, Shah, Dipak J.
• Primary Examiner(s): RIVELL, JOHN A
• Application Number:
  US07/946,243
• Time in Patent Office: 629 Days
• Field of Search: 163/22, 236/49.3, 236/1 B, 237/8 R
• US Class Current: 165/208
• 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 11/76 by means responsive to temperature, e.g. bimetal springs
• CPC Class Codes: F24F 11/88 Electrical aspects, e.g. circuits
• CPC Class Codes: F24F 2110/10 Temperature
• CPC Class Codes: G05D 23/1934 each space being provided with one sensor acting on one or more control means

Abstract

The present invention describes an apparatus and method for controlling the temperature in a plurality of comfort zones within a house or building. The invention contemplates a series of zone control devices which are selectively opened or closed to allow heating and/or cooling to individual zones. The temperature in each zone is sensed and compared to a preferred setpoint temperature to determine a temperature error for each zone. The respective temperature error signals for each zone are used to determine the zone of greatest thermal error. The zone of greatest thermal error is used to turn the heating/cooling plant on and off. The remaining zone or zones of lesser thermal error have their zone control devices closed or opened, depending upon the temperature error signal for their respective zones. In this manner, all zones are synchronized to the zone of greatest thermal error and to the cycle of the heating/cooling plant.

Claims

1. A zone control apparatus comprising:

a plurality of comfort zones;

of zone temperature sensor means, one in each of said plurality of comfort zones for generating a first signal representing the temperature of its respective comfort zone;

a plurality of zone setpoint temperature input means, one for each of said plurality of comfort zones for generating a second signal representative of a preferred temperature for its respective comfort zone;

a plurality of zone control means, each for controlling one of said plurality of comfort zones;

a zone controller means for determining a zone temperature error for each of said plurality of comfort zones based upon said first signal for each of said comfort zones and said second signal for each of said comfort zones, for identifying a zone of greatest thermal error distinct from zones of lesser thermal error, for determining a time for which each respective one of said zone control means should be opened, for controlling the opening and closing of said zone control means based upon said zone temperature errors or said time; and

synchronizing means for synchronizing a heating/cooling plant on/off cycle to open/close said zone control means.

2. A zone control apparatus as recited in claim 1 wherein said zone control means includes a means for determining said zone temperature errors as the difference between said first signal and said second signal from each of said plurality of comfort zones.

3. A zone control apparatus as recited in claim 1 wherein said zone controller means includes an integrating means for integrating a difference between said first signal and said second signal of each of said comfort zones for determining said zone of greatest thermal error.

4. A zone control apparatus as recited in claim 1 wherein said heating/cooling plant is a forced air system.

5. A zone control apparatus as recited in claim 4 wherein said zone control means includes a duct damper for each of said plurality of said comfort zones.

6. A zone control apparatus as recited in claim wherein said heating/cooling plant is a hydronic system.

7. A zone control apparatus as recited in claim 6 wherein said zone control means includes a valve for each of said plurality of said comfort zones.

8. A zone control apparatus comprising:

an error measurement means for determining a temperature error for each of a plurality of comfort zones;

a plurality of zone control means, one for each of said plurality of comfort zones;

a program means for identifying a zone of greatest thermal error based upon said temperature error distinct from zones of lesser thermal error, for opening a zone control means for said zone of greatest thermal error; and

a zone controller means for opening all zone control means and for selectively closing zone control means of zones of lesser thermal error based upon said temperature error for each of their respective plurality of comfort zones.

9. A zone control apparatus as recited in claim 8 wherein said error measurement means includes a zone temperature sensor means in each of said plurality of zones for generating a first signal representing the temperature in said comfort zone, a zone setpoint temperature means for generating a second signal representing a preferred temperature of each of said plurality of comfort zones and a determination means for calculating an error signal as a function of said first signal and said second signal.

10. A zone control apparatus as recite in claim 8 wherein said zone control means is a duct damper, one for each of said plurality of comfort zones for a forced air heating/cooling plant.

11. A zone control apparatus as recited in claim 8 wherein said zone control means is a valve, one for each of said plurality of comfort zones for a hydrophonic heating/cooling plant.

12. A zone control apparatus as recited in claim 9 wherein said determining means calculates the difference between said first signal and said second signal as said error signal.

13. A zone control apparatus as recited in claim 9 wherein said determining means calculates the integral of the difference of said first signal and said second signal as said error signal.

14. A zone control apparatus to supply conditioned air to a plurality of comfort zones comprising:

a plurality of comfort zones;

an air temperature conditioning means for modifying the temperature of circulating air;

a distribution means for proportioning said air from said air temperature conditioning means to each of said plurality of comfort zones;

means for circulating said air to cause air to flow through said distribution means to said plurality of comfort zones;

a plurality of dampers, one for each of said plurality of comfort zones, for closing off the flow of air to each of said plurality of comfort zones;

a temperature setting means in each of said plurality of comfort zones for setting a preferred temperature for each of said plurality of comfort zones;

a temperature measuring means in each of said plurality of comfort zones for measuring the actual temperature in each of said plurality of comfort zones;

means for calculating an error determining error signal for each of said plurality of comfort zones, each of said error signals being a function of the difference between said preferred temperature and said actual temperature for each of said plurality of comfort zones;

a time calculation means for determining a duct damper open time for each of said plurality of comfort zones;

an error selection means for selecting a comfort zone having the greatest error signal and designating said one of said plurality of comfort zones as a zone of greatest thermal error (ZGTE) and for designating all remaining comfort zones as zones of lesser thermal error (ZLTE);

a first duct damper opening means for opening said plurality of duct dampers when said air temperature conditioning means is turned on;

a second duct damper opening means for maintaining said duct damper of said zone of greatest thermal error open at all times;

a first duct damper closing means for selectively closing each of said plurality of duct dampers of the zones of lesser thermal error when the error signal of said zone of lesser error is zero or when the duct damper open time for the zone of lesser thermal error has been exceeded and for maintaining said duct damper closed until said air temperature conditioning means has been turned off and again turned on;

a first plant switching means for turning off the air temperature conditioning means when the error signal for the zone of greatest thermal error equals zero; and

a second plant switching means for turning on the air temperature conditioning means when the error signal of the zone of greatest thermal error exceeds a predetermined differential switching error.

15. A method of controlling the temperature in a plurality of comfort zones comprising the steps of:

generating an error signal for each of a plurality of comfort zones, wherein said error signal is a function of the difference between a measured temperature and a preferred setpoint temperature;

providing a zone control device for each of said plurality of comfort zones;

determining a zone of greatest thermal error from said error signals as opposed to zones of lesser thermal error;

opening the zone control device of the zone of greatest thermal error; and

selectively closing the zone control devices of the zones of lesser thermal error, wherein the error signal for each of the zones of lesser thermal error reaches zero, or when a predetermined open time has been exceeded.

16. A method of controlling the temperature in a plurality of comfort zones as recited in claim 15, wherein the step of generating an error signal includes determining the difference between a preferred setpoint temperature and a measured temperature.

17. A method of controlling the temperature in plurality of comfort zones as recited in claim 15, wherein the step of generating an error signal includes integrating the difference between a preferred setpoint temperature and a measured temperature.

18. A method of controlling the temperature in a plurality of comfort zones comprising the steps of:

providing a plurality of comfort zones;

providing a plurality of zone temperature sensors, one in each of said plurality of comfort zones;

providing a plurality of zone setpoint temperature input means, one in each of said plurality of comfort zones;

providing a plurality of zone control means, each for controlling one of said plurality of said comfort zones;

determining a zone temperature error for each of said plurality of comfort zones from said zone temperature sensors and said temperature input means;

determining a zone of greatest thermal error based upon said zone temperature error;

designating the remaining comfort zones as zones of lesser thermal error;

opening the zone control means for the zone of greatest thermal error; and

selectively closing the zone control means for each of the zones of lesser thermal error when said error signal for that zone equals zero.

19. A method of controlling the temperature in a plurality of comfort zones as recited in claim 18, wherein said step of determining a zone temperature error includes integrating the difference between the zone temperature sensor and said temperature input means to determine a temperature error for each of said plurality of comfort zones.

20. A method of controlling the temperature in a plurality of comfort zones comprising the steps of:

measuring the temperature in each comfort zone and creating a first signal representative of the temperature measured;

setting a preferred temperature for each of the comfort zones and generating a second signal representative of a preferred setpoint temperature;

determining an error signal by calculating the difference between the first signal and the second signal for each of the comfort zones;

determining the zone of greatest thermal error as the comfort zone having the greatest error;

designating the remaining comfort zones as zones of lesser thermal error;

turning on a heating/cooling plant to supply temperature conditioned air to each comfort zone when the error of the zone of greatest thermal error exceeds a predetermined level;

providing an air flow control means in each of said comfort zones;

opening the air flow control means for each zone when the heating/cooling plant is turned on;

maintaining the air control means for the zone of greatest thermal error open during the heating/cooling plant on cycle;

selectively closing the air flow means to each of the zones of lesser thermal error when the error signal for that particular comfort zones equals zero; and

turning off the heating/cooling plant when the error signal for the zone of greatest thermal error equals zero.

21. A method for controlling the temperature in a plurality of comfort zones as recited in claim 20, wherein the step of determining the zone of greatest thermal error is sequentially determined by polling each of the zones of lesser thermal error, closing their respective dampers as required, eliminating zones of lesser thermal error whose duct dampers have been closed and recalculating a zone of greatest thermal error from those zones whose duct dampers are open.