Optimizer for multiple staged refrigeration systems

Abstract

A method and system for dynamically controlling heaters and compressors of multiple zone heating and cooling systems to modulate supply air temperature values to within a predetermined range and operable in a plurality of stages. The system includes a supply air temperature sensor operable to determine the supply air temperature values. The system also includes a control device configured to determine a plurality of system status conditions and activates and inactivates the heaters and compressors in a plurality of stages based on at least some of the plurality of system status conditions.

What is claimed is: 
     
         1 . A method of dynamically controlling heaters and compressors of a multiple zone heating and cooling system operable in a plurality of heater stages and compressor stages including a supply air temperature sensor, the method comprising:
 providing a controller in communication with said supply air temperature sensor and operable to receive supply air temperature values from said supply air temperature sensor;   obtaining a plurality of system status conditions;   staging said plurality of heater stages and compressor stages to modulate said supply air temperature values to within a predetermined range based on at least some of said system status conditions.   
     
     
         2 . The method of  claim 1 , wherein said multiple zone heating and cooling system is a packaged multiple zone heat pump with compression refrigeration system. 
     
     
         3 . The method of  claim 1 , wherein said multiple zone heating and cooling system is a rooftop unit compressor. 
     
     
         4 . The method of  claim 1 , wherein said plurality of system status conditions comprise at least one of a minimum supply air temperature for cooling, maximum supply air temperature for cooling, maximum supply air temperature for heating, rotation time period, number of compressor stages, and minimum time interval between system activation and inactivation. 
     
     
         5 . The method of  claim 1 , wherein obtaining a plurality of system status conditions further comprises providing at least one additional controller in communication with and operable to send said plurality of system status conditions to said controller. 
     
     
         6 . The method of  claim 1 , wherein staging said plurality of heater stages and compressor stages to modulate said supply air temperature values to within a predetermined range based on at least some of said system status conditions further comprises determining a system operating mode. 
     
     
         7 . The method of  claim 6 , wherein determining a system operating mode further comprises providing at least one additional controller in communication with and operable to send said system operating mode to said controller. 
     
     
         8 . The method of  claim 6 , wherein determining a system operating mode further comprises determining said system mode in at least one of a heating mode, a cooling mode, and a ventilation/circulation mode. 
     
     
         9 . The method of  claim 8 , wherein determining a system in at least one of a heating mode, a cooling mode, and a ventilation/circulation mode further comprises:
 providing an outside air temperature sensor in communication with said controller;   measuring outside air temperature values with said outside air temperature sensor;   comparing said outside air temperature values with a predetermined outside air temperature value;   assigning said heating mode when said outside temperature values are lower than said predetermined outside air temperature value;   assigning said cooling mode when said outside air temperature values are higher than said predetermined outside air temperature value;   assigning said circulation/ventilation mode when said outside air temperature values are neither higher than said predetermined outside air temperature value nor lower than said predetermined outside air temperature value.   
     
     
         10 . The method of  claim 8 , wherein determining a system operating mode in at least one of a heating mode, a cooling mode, and a circulation/ventilation mode further comprises:
 assigning said cooling mode when said supply air temperature values are lower than a maximum cooling supply air temperature set point and at least one of said plurality of compressor stages is active;   assigning said cooling mode when said supply air temperature values are lower than a maximum cooling supply air temperature set point and all of said plurality of compressor stages and heater stages are inactive;   assigning said heating mode when said supply air temperature values are above a predetermined minimum heating supply air temperature value and at least one of said plurality of heater stages is active;   assigning said heating mode when said supply air temperature values are above a predetermined minimum heating supply air temperature value and all of said plurality of compressor stages and heater stages are inactive;   assigning said circulation/ventilation mode when said supply air temperature values are between a predetermined minimum and maximum cooling set point and said plurality of compressor stages and heater stages are inactive.   
     
     
         11 . The method of  claim 3 , wherein staging said plurality of heater stages and compressor stages to modulate said supply air temperature values further comprises:
 activating a first heater stage for a predetermined period of time;   activating an additional heater stage when said supply air temperature values are lower than a predetermined minimum heating temperature;   deactivating said first heater stage when said supply air temperature values are above a predetermined maximum heating temperature;   activating a first compressor stage when said supply air temperature values are above a predetermined maximum cooling temperature;   deactivating said first compressor stage when said supply air temperature values are below a predetermined minimum cooling temperature;   activating a second compressor stage when said supply air temperature values are above a predetermined maximum cooling temperature;   deactivating said second compressor stage when said supply air temperature values are below a predetermined minimum cooling temperature;   activating additional compressor stages when said supply air temperature values are above a predetermined maximum cooling temperature;   deactivating said additional compressor stages when said supply air temperature values are below a predetermined minimum cooling temperature.   
     
     
         12 . The method of  claim 2 , wherein staging said plurality of heater stages and compressor stages further comprises the steps of:
 activating a first heater stage for a predetermined period of time and setting said hot/cold switch valve to said heating mode;   deactivating said first heater stage when said supply air temperature values are above a predetermined maximum heating temperature;   activating a first compressor stage when said heater stages and compressors stages are deactivated, said supply air temperature values are above a maximum cooling temperature set point, and said hot/cold switch valve is set to said cooling mode;   activating a first compressor stage when transitioning from said cooling mode to said circulation mode, and said hot/cold switch valve is set to said cooling mode;   deactivating said first compressor stage when said supply air temperature values are below a predetermined minimum cooling temperature value;   activating a second compressor stage when said supply air temperature values are above a predetermined maximum cooling temperature value in a predetermined period of time;   deactivating said second compressor stage when said supply air temperature values are below a predetermined minimum cooling temperature value;   activating additional compressor stages when said supply air temperature values are above a predetermined maximum temperature value in said cooling mode and when at least two or more compressor stages are already active;   deactivating said additional compressor stages when said supply air temperature values are below a predetermined minimum temperature value in said cooling mode and when at least two or more compressor stages are activated;   activating an additional compressor stage when said supply air temperature values are below a predetermined minimum temperature value in said heating mode and when at least two or more compressor stages are activated;   deactivating an additional compressor stage when said supply air temperature values are above a predetermined maximum temperature value in said heating mode and when at least two or more compressor stages are activated.   
     
     
         13 . An optimizer for dynamically controlling heaters and compressors of a multiple zone heating and cooling system to modulate supply air temperature values to within a predetermined range, the optimizer comprising:
 a supply air temperature sensor operable to determine said supply air temperature values;   a control device linked in communication with said supply air temperature sensor and configured to determine a plurality of system status conditions, and based on at least some of said plurality of system status conditions, activate and inactivate said heaters and compressors in a plurality of stages.   
     
     
         14 . The optimizer of  claim 13 , wherein said plurality of system status conditions are further comprised of at least one of a minimum and maximum supply air temperature for cooling, a maximum heating supply air temperature, number of stages, rotation time period, and minimum time interval between system activation and inactivation. 
     
     
         15 . The optimizer of  claim 13 , further comprising:
 an outside air temperature sensor linked in communication with said control device and operable to measure outside air temperature values;   a supervisory controller linked in communication with said control device and operable to send said plurality of system status conditions to said control device.   
     
     
         16 . The optimizer of  claim 13 , wherein said control device is further comprised of a plurality of modules comprising:
 an interface module configured to interface said system information between a human operator and said control device and from an additional controller and said control device;   a sequence module configured to alter the order of said heaters and compressors based on a rotation time interval;   a mode identification module configured to determine a plurality of operating modes;   a control module configured to activate and inactivate said heaters and compressors in said plurality of heater stages and compressor stages.   
     
     
         17 . The optimizer of  claim 16 , wherein said mode identification module is further configured to determine said plurality of operating modes in one of:
 a cooling mode when said supply air temperature values are lower than a maximum cooling supply air temperature set point and at least one of said plurality of compressor stages is active;   a cooling mode when said supply air temperature values are lower than a maximum cooling supply air temperature set point and all of said plurality of compressor stages and heater stages are inactive;   a cooling mode when outside air temperature values are higher than a predetermined outside air temperature value;   a heating mode when said supply air temperature values are below a predetermined minimum heating supply air temperature value and at least one of said plurality of heater stages is active;   a heating mode when said supply air temperature values are above a predetermined minimum heating supply air temperature value and all of said plurality of compressor stages and heater stages are inactive;   a heating mode when outside air temperature values are lower than a predetermined outside air temperature;   a circulation/ventilation mode when said supply air temperature values are between a predetermined minimum and maximum cooling set point and said plurality of compressor stages and heater stages are inactive;   a circulation/ventilation mode when outside air temperature values are neither higher than a predetermined outside air temperature value nor lower than said predetermined outside air temperature value.   
     
     
         18 . The optimizer of  claim 13 , wherein said multiple zone heating and cooling system is a rooftop unit compressor operable in a plurality of heater stages and compressor stages further comprising:
 a first heater stage operable to activate for a predetermined period of time, and operable to deactivate when said supply air temperature values are above a predetermined maximum heating temperature;   additional heater stages operable to activate after the activation of said first heater stage when said supply air temperature values are higher than a predetermined minimum temperature, and operable to deactivate when said supply air temperature values are below a predetermined minimum temperature;   a first compressor stage operable to activate when said supply air temperature values are higher than a predetermined maximum temperature, and operable to deactivate when said supply air temperature values are lower than a predetermined minimum temperature;   additional compressor stages operable to activate after the activation of said first compressor stage when said supply air temperature values are above a predetermined maximum temperature, and operable to deactivate when said supply air temperature values are below a predetermined minimum temperature.   
     
     
         19 . The optimizer of  claim 13 , wherein said multiple zone heating and cooling systems is a packaged multiple zone heat pump with compression refrigeration system comprising:
 a plurality of relays configured to operate said heaters and compressors in a plurality of heater stages and compressor stages;   a switch valve operable to transition said packaged multiple zone heat pump with compression refrigeration system between one of a cooling mode and a heating mode.   
     
     
         20 . The optimizer of  claim 19 , wherein said plurality of heater stages and compressor stages further comprise:
 a first heater stage operable to activate for a predetermined period of time when said hot/cold switch valve is in said heating mode, and operable to deactivate when said supply air temperature values are above a predetermined maximum heating temperature;   a first compressor stage operable to activate when said supply air temperature values are above a predetermined maximum cooling temperature set point and said hot/cold switch valve is set in said cooling mode, and operable to deactivate when said supply air temperature values are below a predetermined minimum cooling temperature value;   a second compressor stage operable to activate when said supply air temperature values are above a predetermined maximum cooling temperature value in a predetermined time period, and operable to deactivate when said supply air temperature values are below a predetermined maximum cooling temperature value;   additional compressor stages operable to activate when said supply air temperature values are above a predetermined maximum temperature value in said cooling mode, and operable to deactivate when said supply air temperatures are below a predetermined minimum temperature value in said cooling mode;   additional compressor stages operable to activate when said supply air temperature values are below a predetermined minimum temperature value in said heating mode, and operable to deactivate when said supply air temperature values are above a predetermined maximum temperature value in said heating mode.