Adaptive anticipator mechanism for limiting room temperature swings

• US 4,901,918 A
• Filed: 02/27/1989
• Issued: 02/20/1990
• Est. Priority Date: 02/27/1989
• Status: Expired due to Term

• Current Assignee: Gas Technology Institute (GTI Energy)
• Original Assignee: Gas Research Institute (GTI Energy)
• Inventors: MacArthur, J. Ward, Grald, Eric W.
• Primary Examiner(s): Wayner, William E.
• Application Number:
  US07/315,850
• Time in Patent Office: 358 Days
• Field of Search: 364/143, 364/557, 236/46 R, 236/1 R, 236/78 D, 165/12
• US Class Current: 236/78.00D
• CPC Class Codes: G05D 23/1909 whose output amplitude can only take two discrete values
• CPC Class Codes: G05D 23/20 with sensing elements having variation of electric or magnetic properties with change of temperature G05D23/13 takes precedence

Abstract

An adaptive cycle rate thermostat control. A thermostat including a switch and apparatus for heat anticipation operates responsively to an anticipator time constant. Apparatus for sensing room temperature provides an electronic signal proportional to the room temperature sensed. Apparatus for providing an acitivation signal to the switch responsive to the heat anticipation apparatus and sensed temperature cycles a variable-speed heat pump. Apparatus for modifying the anticipator time constant in response to room temperature swings provides the modified anticipator time constant to the heat anticipation means so as to keep room temperature swings within desirable limits while operating the heat pump more efficiently.

Claims

1. An adaptive cycle rate thermostat control comprising:

(a) a thermostat including a switch and a means for heat anticipation which operates responsively to an anticipator time constant and a first error signal;

(b) means for sensing room temperature and providing an electronic signal corresponding to the room temperature to the thermostat;

(c) means for sampling the electronic signal from the sensing means, the sampling means being connected to the output of the sensing means;

(d) means for calculating the room temperature swing based on discerning the maximum and minimum temperatures sampled in the sampling means;

(e) means for comparing the calculated room temperature swing to a predetermined value so as to provide a second error signal;

(f) means for modifying the anticipator time constant wherein the modifying means is responsive to the value of the second error signal; and

(g) means for providing an activation signal to the switch responsive to the heat anticipation means.

2. The apparatus of claim 1 wherein the means for modifying the anticipator time constant comprises proportional, integral and derivative gain blocks which operate on the second error signal and whose outputs are processed through a summing point which, in turn, provides a modified value for the anticipator time constant.

3. The apparatus of claim 2 wherein the means for modifying the anticipator time constant further includes a means for limiting the minimum and maximum values of the anticipator time constant.

4. The apparatus of claim 1 wherein the first error signal is provided by a second means for comparing the temperature set point to the sensed room temperature.

5. The apparatus of claim 4 wherein the activation signal is generated by a third means for comparing which compares the first error signal with the output provided by the heat anticipation means.

6. The apparatus of claim 5 wherein the means for modifying the anticipator time constant comprises proportional, integral and derivative gain blocks which operate on the second error signal and are processed through a summing point which, in turn, provides a modified value for the anticipator time constant.

7. The apparatus of claim 6 wherein the means for modifying the anticipator time constant further includes a means for limiting the minimum and maximum values of the anticipator time constant.

8. An adaptive cycle rate thermostat control comprising:

(a) a thermostat including a switch and means for heat anticipation which operates responsively to an anticipator time constant;

(b) means for sensing room temperature and providing an electronic signal proportional to the room temperature sensed to the thermostat;

(c) means for providing an activation signal to the switch responsive to the heat anticipation means and sensed temperature;

(d) means for modifying the anticipator time constant in response to room temperature swings as calculated from the sensed room temperature and providing the modified anticipator time constant to the heat anticipation means.

9. The apparatus of claim 8 wherein the means for modifying the anticipator time constant comprises proportional, integral and derivative gain blocks which operate on an error signal corresponding to the difference between the sensed temperature room swing and a predetermined value and whose outputs are processed through a summing point which, in turn, provides a modified value for the anticipator time constant.

10. The apparatus of claim 9 wherein the means for modifying the anticipator time constant further includes a means for limiting the minimum and maximum values of the anticipator time constant.

11. The apparatus of claim 8 further including an error signal provided to the thermostat by a first means for comparing a predetermined temperature set point to the sensed room temperature.

12. The apparatus of claim 11 wherein the activation signal is generated by a second means for comparing which compares the error signal with the output provided by the heat anticipation means.

13. The apparatus of claim 12 wherein the means for modifying the anticipator time constant comprises proportional, integral and derivative gain blocks which operate on a second error signal corresponding to the difference between the sensed temperature room swing and a predetermined value and whose outputs are processed through a summing point which, in turn, provides a modified value for the anticipator time constant.

14. The apparatus of claim 13 wherein the means for modifying the anticipator time constant further includes a means for limiting the minimum and maximum values of the anticipator time constant.

15. An adaptive anticipator mechanism for limiting room temperature swings comprising:

(a) means for sensing room temperature having an output providing a signal proportional to the sensed room temperature;

(b) first means for comparing the sensed room temperature signal with a predetermined temperature set point signal and generating a first error signal representing the difference;

wherein the first comparing means is connected to the output of the temperature sensing means;

(c) means for sampling connected to the output of the temperature sensing means wherein the sampling means operates to calculate the sensed temperature room swing and has an output which provides a signal representing the sensed temperature room swing;

(d) a second means for comparing which receives the sensed temperature room swing signal, compares it to a predetermined value and provides the resultant difference as a second error signal;

(e) means for providing gain to the second error signal having an output signal representing the heat anticipation time constant;

(f) means for receiving the heat anticipation time constant and applying maximum and minimum limitations to the heat anticipation time constant;

(g) means for providing heat anticipation responsive to the limited heat anticipation time constant, wherein the heat anticipation means provides an anticipation signal;

(h) third means for comparing the first error signal with the anticipation signal received from the heat anticipation means so as to generate an activation signal from the resultant difference; and

(i) means for switching responsive to the activation signal.

16. The apparatus of claim 15 wherein the means for providing gain comprises proportional, integral and derivative gain blocks which operate on the second error signal and whose outputs are processed through a summing point which, in turn, provides a modified value representing heat anticipation time constant.