High-frequency control of devices internal to a hermetic compressor

Abstract

A system for transmitting control signals to internal devices of a compressor is provided. The compressor includes a housing, a hermetic power terminal and a motor for powering the compressor. The system includes a frequency converter that is disposed externally of the compressor housing. The frequency converter converts a control signal to a high-frequency signal. A frequency decoder is disposed inside the compressor housing. The frequency decoder decodes and converts the high-frequency signal to a driver signal. An AC input power source provides electrical power to the motor, and power transmission lines connect the AC input power source to the hermetic power terminal. The frequency converter is electrically coupled to the frequency decoder by two power transmission lines. The frequency decoder generates a driver signal in response to the high frequency signal for operating at least one of the internal devices of the compressor.

1 . A system for transmitting control signals to internal devices of a compressor, wherein the compressor includes a housing, a sealed power terminal, and a motor for powering the compressor, the system comprising:
 a first signal converter disposed externally of the compressor housing, the first signal converter being configured to receive a control signal and convert the control signal to a modulated signal;   a second signal converter disposed internally of the compressor housing, the second signal converter being configured to decode the modulated signal;   a plurality of power transmission lines connected to an AC input power source, the plurality of power transmission lines also connected to the sealed power terminal;   wherein the first signal converter is electrically coupled to at least one power transmission line of the plurality of transmission lines to transmit the modulated signal to the second signal converter, and the second signal converter is coupled to the at least one power transmission line and configured to receive the modulated signal and to generate a driver signal in response to the modulated signal for operating at least one of the internal devices of the compressor.   
   
   
       2 . The system of  claim 1 , wherein the first signal converter is a frequency converter and the second signal converter is a frequency decoder; the frequency converter configured to convert the modulated signal to a high-frequency signal. 
   
   
       3 . The system of  claim 1 , wherein the first signal converter modulates the signal using a modulating technique selected from one of frequency modulation (FM), amplitude modulation (AM), burst encoding or digital encoding. 
   
   
       4 . The system of  claim 1 , wherein the second converter is configured to convert a second signal received from at least one device disposed within the compressor, and convert the second signal to a modulated second signal, and the first converter is configured to receive the modulated second signal and convert the modulated second signal to a data signal or an external control signal. 
   
   
       5 . The system of  claim 1 , wherein the at least one internal device of the compressor is an internal solenoid valve configured to modulate the capacity of the compressor in response to the generated driver signal. 
   
   
       6 . The system of  claim 1 , wherein the at least one internal device of the compressor is an internal solenoid valve, the internal solenoid valve being disposed between a high-pressure side of the compressor and a low-pressure side of the compressor, the internal solenoid valve configured to equalize the high-pressure side and the low-pressure side in response to the generated driver signal. 
   
   
       7 . The system of  claim 6 , wherein the internal solenoid valve is a normally open valve that is actuated to the closed position in response to the generated driver signal when the compressor is operating. 
   
   
       8 . The system of  claim 6 , wherein the internal solenoid valve is a normally closed valve that is actuated to the closed position in response to the generated driver signal when the compressor is operating. 
   
   
       9 . The system of  claim 6 , wherein the pressure of the high-pressure side and the low-pressure side provides reduced torque on the motor for a delay period. 
   
   
       10 . The system of  claim 9 , wherein the delay period is equal to the time for the motor to reach a predetermined operating speed. 
   
   
       11 . The system of  claim 1 , wherein the first converter and the second converter are each connected between a conductor of the AC input power source and the compressor housing 
   
   
       12 . The system of  claim 1 , wherein the AC input power source is a multi-phase power source and the first converter and the second converter are each connected across two corresponding phases of a multi-phase AC power input. 
   
   
       13 . The system of  claim 1 , wherein the AC input power source is a single phase power source and the first converter and the second converter are each connected between a neutral conductor and a power conductor of the single phase power source. 
   
   
       14 . A refrigeration system comprising:
 a compressor, a condenser, and an evaporator connected in a closed refrigerant loop the compressor having a motor to power the compressor and wherein the compressor includes a housing and a hermetic power terminal;   a frequency converter disposed externally of the compressor housing, the frequency converter configured to receive a control signal and convert the control signal to a high-frequency signal;   a frequency decoder disposed internally of the compressor housing, the frequency decoder configured to decode the high-frequency signal and convert the high-frequency signal to a driver signal; and   a plurality of power transmission lines connected to the hermetic power terminal;   wherein the frequency converter is electrically coupled to at least one power transmission line of the plurality of transmission lines to transmit the high-frequency signal to the frequency decoder, and the frequency decoder is coupled to the at least one power transmission line and configured to receive the high-frequency signal and to generate a driver signal in response to the high-frequency signal for operating at least one of the internal devices of the compressor.   
   
   
       15 . The system of  claim 14 , wherein the frequency decoder is configured to convert a second signal received from at least one device disposed within the compressor, and convert the second signal to a second high-frequency signal, and the first converter is configured to receive the second high-frequency signal and convert the second high-frequency signal to a data signal or an external control signal. 
   
   
       16 . The system of  claim 14 , wherein the at least one internal device of the compressor is an internal solenoid valve configured to modulate the capacity of the compressor in response to the generated driver signal. 
   
   
       17 . The system of  claim 14 , wherein the at least one internal device of the compressor is an internal solenoid valve, the internal solenoid valve being disposed between a high-pressure side of the compressor and a low-pressure side of the compressor, the internal solenoid valve configured to equalize the high-pressure side and the low-pressure side in response to the generated driver signal. 
   
   
       18 . The system of  claim 17 , wherein the internal solenoid valve is a normally open valve that is actuated to the closed position in response to the generated driver signal when the compressor is operating. 
   
   
       19 . The system of  claim 17 , wherein the internal solenoid valve is a normally closed valve that is actuated to the open position in response to the generated driver signal when the compressor is operating. 
   
   
       20 . The system of  claim 17 , wherein the pressure of the high-pressure side and the low-pressure side provides reduced torque on the motor for a delay period. 
   
   
       21 . A method for controlling internal devices of a hermetic compressor wherein the compressor includes a housing, a hermetic power terminal and a motor for powering the compressor, the method comprising:
 receiving a control signal;   converting the control signal to a high-frequency signal;   transmitting the high-frequency signal on an AC input power line of the compressor;   decoding the high-frequency signal;   generating a driver signal in response to the decoded high-frequency signal; and   controlling an internal device of the hermetic compressor using the generated driver signal.