Discharge pressure estimation for compressor

Abstract

A compressor has a controller which is provided with current information for a current passing into a motor associated with the compressor. The compressor includes a compressor pump unit driven by the motor, and a discharge line. The controller is programmed to utilize the current information to predict a discharge pressure at the discharge of the compressor.

1 . A compressor comprising:
 a controller provided with current information for a current passing into a motor associated with said compressor, said compressor including a compressor pump unit driven by said motor, and a discharge line; and   said controller being programmed to utilize said current information to predict a discharge pressure at the discharge of the compressor.   
     
     
         2 . The compressor as set forth in  claim 1 , wherein a suction pressure sensor provides suction pressure information to said controller. 
     
     
         3 . The compressor as set forth in  claim 2 , wherein a temperature at the motor is utilized to fine-tune the discharge pressure estimate. 
     
     
         4 . The compressor as set forth in  claim 1 , wherein said controller also takes in information from a location remote from said compressor and utilizes said information to calculate an alternative discharge pressure estimate, and said alternative discharge pressure estimate being compared to said discharge pressure estimate based upon current, and an indication of a potential problem being made should said two pressures differ by more than a predetermined amount. 
     
     
         5 . The compressor as set forth in  claim 1 , wherein the controller is provided with curves correlating current with discharge pressure and these are utilized to calculate the discharge pressure.