Override of nonoccupancy status in a thermostat device based upon analysis of recent patterns of occupancy
View Patent ↗A thermostat system with a thermostat control program is disclosed for controlling a Heating Ventilation and/or Air Conditioning (HVAC) system which incorporates a mechanism for detecting activity or occupancy in a room, area or conditioned space served by the HVAC system. The thermostat control program analyzes levels, counts or other aspects of activity detected in the conditioned space, with an operating sequence which may include pattern recognition techniques. The operating sequence of the thermostat control program may further depend upon time of day, and upon periods of time identified as being periods for special handling of occupancy, or the recognition of occupancy. These factors may then be utilized by the thermostat control program to influence determination of the temperature setpoint, or to select from alternative programming provided either by the user of the thermostat, or by factory programming, with purpose of balancing energy savings and comfort.
1. A control apparatus for controlling space conditioning equipment serving a conditioned space, the apparatus comprising:
a thermostat control unit, which includes a processor, and a computer memory, running under control of a thermostat control program component;
a temperature sensor coupled to the thermostat control unit for providing a signal indicative of current temperature in the conditioned space;
an occupancy sensor coupled to the thermostat control unit generating a signal indicative of current activity in the conditioned space;
a user input mechanism to establish a user desired occupied conditioned space setpoint temperature;
the thermostat control program component including instructions defining logic and related data stored in the computer memory, the instructions defining logic and related data including:
A) instructions for monitoring the signal indicative of current activity and defining an operating sequence to establish a condition of actual occupancy, and to recognize within a recent time interval a pattern of activity described by a timing of a plurality of the signals indicative of current activity and received within that recent time interval;
B) instructions for initiating a condition of occupancy extension upon recognition of the pattern of activity, and maintaining that condition over an extension time period;
C) instructions for forming and maintaining a calculated condition of occupancy which is deemed valid only during the condition of actual occupancy or the condition of occupancy extension;
D) instructions to signal the space conditioning equipment, when the condition of occupancy extension exists, such as to bring the current temperature in the conditioned space closer to the user desired occupied conditioned space temperature,
and in the absence of the condition of occupancy extension, to operate so as to reduce energy usage by the space conditioning equipment.
2. The control apparatus of claim 1 , in which the pattern of activity spans an interval of time longer than fifteen minutes.
3. The control apparatus of claim 1 , in which the recent time interval utilized during recognition of the pattern of activity is more than thirty minutes and less than two hours.
4. The control apparatus of claim 1 in which the extension time period extends at least thirty minutes beyond the end of the condition of actual occupancy.
5. The control apparatus of claim 1 which further includes a real time clock providing at least current time of day information to the thermostat control program, and the extension time period is determined utilizing the current time of day information.
6. The control apparatus of claim 1 which includes further a real time clock providing at least current time of day information to the thermostat control program, and in which upon detecting the pattern of activity, the thermostat control program component extends in time the calculated condition of occupancy for an extension period which is selected from a set of possible extension time periods with selection based upon the current time of day information.
7. The control apparatus of claim 1 in which the operating sequence to recognize the pattern of activity includes:
A) defining a time period for pattern matching that spans greater than 10 minutes;
B) sub-dividing the time period for pattern matching into a plurality of sub-time periods;
C) checking for activity in a selected number of sub-time periods, with the selected number being more than one but not necessarily all of the sub-time periods, and identifying the recognized pattern of activity when activity is detected in at least said selected number of sub-time periods.
8. The control apparatus of claim 7 in which the operating sequence to recognize the pattern of activity further requires that the selected number of sub-time periods be congruent.
9. The control apparatus of claim 7 in which the operating sequence to recognize the pattern of activity is further based upon a count of number of occurrences of the signal indicative of current activity.
10. The control apparatus of claim 7 in which the operating sequence to recognize the pattern of activity is further based upon a count of a number of occurrences of the signal indicative of current activity in a plurality of the sub-time periods.
11. A control apparatus for controlling space conditioning equipment serving a conditioned space, the apparatus comprising
a thermostat control unit, which includes a microprocessor and computer memory, running under control of a thermostat control program component;
a temperature sensor coupled to the thermostat control unit for providing a signal indicative of current temperature in the conditioned space;
an occupancy sensor coupled to the thermostat control unit generating a signal indicative of current activity in the conditioned space;
a user input mechanism to establish a user desired occupied conditioned space setpoint temperature and a user desired unoccupied conditioned space setpoint temperature;
the thermostat control program component including instructions defining logic and related data stored in the computer memory and being operative with:
A) instructions for monitoring the signal indicative of current activity to establish a condition of actual occupancy, and to recognize within a recent time interval a pattern of activity described by a timing of a plurality of the signals indicative of current activity and received in that recent time interval;
B) instructions for initiating a condition of occupancy extension upon recognition of the pattern of activity, and maintaining that condition over an extension time period;
C) instructions for forming and maintaining a calculated condition of occupancy which is deemed valid only during the condition of actual occupancy or the condition of occupancy extension;
D) instructions to establish a user's currently desired conditioned space temperature by selecting, based upon the calculated condition of occupancy, from either a) the user desired unoccupied conditioned space setpoint temperature, or, b) the user desired occupied conditioned space setpoint temperature and to signal the space conditioning equipment to operate so as to bring the current temperature in the conditioned space closer to the user's currently desired conditioned space temperature.
12. A method for operating a control apparatus for controlling space conditioning equipment serving a conditioned space, the apparatus comprising
a thermostat control unit, which includes a processor, and a computer memory, running under control of a thermostat control program component;
a temperature sensor coupled to the thermostat control unit for providing a signal indicative of current temperature in the conditioned space;
an occupancy sensor coupled to the thermostat control unit generating a signal indicative of current activity in the conditioned space;
a user input mechanism to establish a user desired occupied conditioned space setpoint temperature;
the thermostat control unit following steps for:
A) monitoring the signal indicative of current activity and
1) based upon that signal establishing a condition of actual occupancy; and
2) recognizing within a recent time interval a pattern of activity described by a timing of a plurality of the signals indicative of current activity received in that recent time interval;
B) upon recognition of the pattern of activity, initiating a condition of occupancy extension, and maintaining that condition over an extension time period;
C) forming and maintaining a calculated condition of occupancy which is deemed valid only during the condition of actual occupancy or the condition of occupancy extension;
D) when the condition of occupancy extension exists, operating in a mode of normal energy usage and signaling the space conditioning equipment such as to bring the current temperature in the conditioned space closer to the user desired occupied conditioned space temperature,
and in the absence of the condition of occupancy extension, operating in a mode for reduced energy usage in comparison to the energy expected to be used during the mode of normal energy usage.
13. A control apparatus for controlling space conditioning equipment serving a conditioned space, the apparatus comprising
a thermostat control unit, which includes a microprocessor and computer memory, running under control of a thermostat control program component;
a temperature sensor coupled to the thermostat control unit for providing a signal indicative of current temperature in the conditioned space;
an occupancy sensor coupled to the thermostat control unit generating a signal indicative of current activity in the conditioned space;
a user input mechanism to establish a user desired occupied conditioned space setpoint temperature and a user desired unoccupied conditioned space setpoint temperature;
the thermostat control program component including instructions defining logic and related data stored in the computer memory and being operative with:
A) instructions for monitoring the signal indicative of current activity to establish a condition of actual occupancy, and to determine within a recent time interval a pattern of activity described by a timing of a plurality of the signals indicative of current activity and received in that recent time interval;
B) instructions for initiating a condition of occupancy extension upon analysis of the pattern of activity, and maintaining that condition over an extension time period;
C) instructions for forming and maintaining a calculated condition of occupancy which is deemed valid only during the condition of actual occupancy or the condition of occupancy extension;
D) instructions to establish a user's currently desired conditioned space temperature by selecting, based upon the calculated condition of occupancy, from either a) the user desired unoccupied conditioned space setpoint temperature, or, b) the user desired occupied conditioned space setpoint temperature and to signal the space conditioning equipment to operate so as to bring the current temperature in the conditioned space closer to the user's currently desired conditioned space temperature.
14. The control apparatus of claim 13 which further includes a real time clock providing at least current time of day information to the thermostat control program, and in which the initiating of the condition of occupancy extension is disabled during certain times of day based upon the current time of day information.
15. The control apparatus of claim 13 which further includes a real time clock providing at least current time of day information to the thermostat control program, and in which the initiating of the condition of occupancy extension is disabled during certain times of day based upon the current time of day information, with further user input from the user input mechanism providing specific times of day for disabling the condition of occupancy extension.
16. The control apparatus of claim 13 which includes further a real time clock providing at least current time of day information to the thermostat control program, and in which upon detecting the pattern of activity, the thermostat control program component extends in time the calculated condition of occupancy for an extension period which is selected from a set of possible extension time periods with selection based upon the current time of day information.
17. A control apparatus for controlling space conditioning equipment serving a conditioned space, the apparatus comprising
a thermostat control unit, which includes a microprocessor and computer memory, running under control of a thermostat control program component;
a temperature sensor coupled to the thermostat control unit for providing a signal indicative of current temperature in the conditioned space;
an occupancy sensor coupled to the thermostat control unit generating a signal indicative of current activity in the conditioned space;
a user input mechanism to establish a user desired occupied conditioned space setpoint temperature and a user desired unoccupied conditioned space setpoint temperature;
the thermostat control program component including instructions defining logic and related data stored in the computer memory and being operative with:
A) instructions for monitoring the signal indicative of current activity to establish a condition of actual occupancy, and to determine, within a recent time interval, patterns of activity, each pattern described by a timing of a plurality of the signals indicative of current activity and received in that recent time interval;
B) instructions for initiating a condition of occupancy extension upon identification of at least one pattern of activity, and maintaining that condition over an extension time period;
C) instructions for forming and maintaining a calculated condition of occupancy which is deemed valid only during the condition of actual occupancy or the condition of occupancy extension;
D) instructions to establish a user's currently desired conditioned space temperature by selecting, based upon the calculated condition of occupancy, from either a) the user desired unoccupied conditioned space setpoint temperature, or, b) the user desired occupied conditioned space setpoint temperature and to signal the space conditioning equipment to operate so as to bring the current temperature in the conditioned space closer to the user's currently desired conditioned space temperature.