Method and systems for operating compressors and fan coils using electronically commutated motors

Abstract

A heating, ventilation, and air conditioning (HVAC) system is described that includes a first unit and a second unit. The first unit comprises a controller configured to output a coded compressor activation signal that is based at least partially on a compressor run signal received from a thermostat. The second unit comprises at least a compressor relay. The second unit is configured to receive and decode the coded compressor activation signal from the first unit and is operable to operate the compressor relay based on the decoded content of the coded compressor activation signal.

1 . A heating, ventilation, and air conditioning system comprising: 
 a first unit comprising a controller configured to output a coded compressor activation signal, the coded compressor signal based at least partially on a compressor run signal received from a thermostat; and    a second unit comprising at least a compressor relay, said second unit configured to receive and decode the coded compressor activation signal from said first unit, said second unit operable to operate said compressor relay based on the decoded content of the coded compressor activation signal.    
   
   
       2 . A heating, ventilation, and air conditioning system according to  claim 1  wherein said first unit comprises a high frequency generator arid said second unit comprises a high pass filter and a detector receiving an output of said high pass filter, said first unit configured to combine a compressor run signal received from a thermostat with the high frequency for output as the coded compressor activation signal.  
   
   
       3 . A heating, ventilation, and air conditioning system according to  claim 2  wherein said first unit comprises a blower motor, said high frequency generator integrated into a controller of said blower motor.  
   
   
       4 . A heating, ventilation, and air conditioning system according to  claim 3  wherein said blower motor comprises an electronically commutated motor.  
   
   
       5 . A heating, ventilation, and air conditioning system according to  claim 2  wherein said second unit comprises a compressor relay, an output of said detector operable to control operation of said compressor relay.  
   
   
       6 . A heating, ventilation, and air conditioning system according to  claim 1  wherein said first unit comprises a blower motor, and wherein to provide a coded compressor activation signal, said first unit configured to combine a compressor run signal received from a thermostat with an identifying signal output by said blower motor.  
   
   
       7 . A heating, ventilation, and air conditioning system according to  claim 6  wherein the compressor run signal and the identifying signal are combined using a resistor.  
   
   
       8 . A heating, ventilation, and air conditioning system according to  claim 7  wherein the compressor activation signal is near ground potential when the output of said blower motor in a low impedance state and at an approximate 24 VAC potential when the output of said blower motor is in a high impedance state.  
   
   
       9 . A heating, ventilation, and air conditioning system according to  claim 1  wherein said second unit comprising at least a plurality of compressor relays, each said relay operable to for activating a different stage of a compressor, said second unit configured to receive and decode the coded compressor activation signal from said first unit, said second unit operable to activate an appropriate one of said compressor relays based on the decoded content of the coded compressor activation signal.  
   
   
       10 . A method for controlling operation of a compressor within a heating, ventilation, and air conditioning system, said method comprising: 
 providing a compressor run signal to a first unit;    utilizing the compressor run signal within the first unit to generate a coded compressor activation signal;    outputting the coded compressor activation signal to a second unit that includes a compressor; and    decoding the coded compressor activation signal within the second unit to determine whether the compressor is to be activated.    
   
   
       11 . A method according to  claim 10  providing a compressor run signal to a first unit comprises utilizing a thermostat to output a compressor run signal.  
   
   
       12 . A method according to  claim 10  wherein utilizing the compressor run signal within the first unit to generate a coded compressor activation signal comprises combining the compressor run signal with a high frequency signal for output as the coded compressor activation signal.  
   
   
       13 . A method according to  claim 12  further comprising integrating a high frequency generator into a controller of a blower motor within the first unit.  
   
   
       14 . A method according to  claim 12  wherein decoding the coded compressor activation signal within the second unit comprises: 
 high pass filtering the coded compressor activation signal;    applying a result of the high pass filtering to a detector; and    controlling operation of the compressor based on an output of the detector.    
   
   
       15 . A method according to  claim 10  wherein utilizing the compressor run signal within the first unit to generate a coded compressor activation signal comprises combining a compressor run signal received from a thermostat with an identifying signal output by a blower motor within the first unit.  
   
   
       16 . A method according to  claim 15  wherein combining the compressor run signal with an identifying signal output comprises combining the compressor run signal and the identifying signal utilizing a resistor.  
   
   
       17 . A method according to  claim 15  wherein combining the compressor run signal with an identifying signal output comprises: 
 outputting a coded compressor activation signal at an approximate ground potential when the identifying signal is in a low impedance state; and    outputting a coded compressor activation signal at an approximate 24 VAC potential when the identifying signal is in a high impedance state.    
   
   
       18 . A method according to  claim 17  wherein decoding the coded compressor activation signal further comprises activating the compressor based on a state of the coded compressor activation signal.  
   
   
       19 . A method according to  claim 10  wherein said decoding the coded compressor activation signal within the second unit to determine whether the compressor is to be activated comprises decoding the coded compressor activation signal to determine which compressor stage should be activated.  
   
   
       20 . A blower unit for a heating, ventilation, and air conditioning system, said blower unit configured to receive a compressor run signal from a thermostat and comprising at least one apparatus configured to generate a signal for combination with the compressor run signal, said blower unit further configured to output a combination of the compressor run signal and generated signal as a coded compressor activation signal.  
   
   
       21 . A blower unit according to  claim 20  wherein said at least one apparatus comprises a high frequency signal generator, said blower unit configured to combine the output of said high frequency signal generator with the compressor run signal.  
   
   
       22 . A blower unit according to  claim 21  further comprising an electronically commutated motor comprising a motor controller, said motor controller configured with said high frequency signal generator.  
   
   
       23 . A blower unit according to  claim 20  further comprising a blower motor, said at least one apparatus configured to combine the compressor run signal with an identifying signal output by said blower motor.  
   
   
       24 . A blower unit according to  claim 23  wherein said at least one apparatus is configured to: 
 output a coded compressor activation signal at an approximate ground potential when the identifying signal is in a low impedance state; and    output a coded compressor activation signal at an approximate 24 VAC potential when the identifying signal is in a high impedance state.    
   
   
       25 . A blower unit according to  claim 20  wherein the coded compressor signal comprises information regarding which stage of a compressor is to be activated.  
   
   
       26 . A unit for controlling operation of a compressor, said unit comprising: 
 a compressor run relay; and    a decoder, said decoder comprising a relay coil driver operable to change a state of said compressor run relay, said decoder configured to receive and decode a coded compressor activation signal from an external source, said decoder operable to activate said relay coil driver based on the decoded content of the coded compressor activation signal.    
   
   
       27 . A unit according to  claim 26  wherein said decoder comprises: 
 a high pass filter; and    a detector, said high pass filter configured to receive the coded compressor activation signal and output a signal to said detector, said detector operable to activate said relay coil driver based on an amplitude of the signal received from said high pass filter.    
   
   
       28 . A unit according to  claim 25  wherein said decoder comprises: 
 a high pass filter; and    a detector, said unit comprising a plurality of compressor run relays each configured for activating a single stage of a compressor, said decoder comprising a respective plurality of relay coil drivers, said detector operable to activate a specific said relay coil driver based on the decoded content of the coded compressor activation signal.