Method and system for reciprocating compressor starting

Abstract

Systems and methods of the invention may overcome a higher than normal starting torque for in a reciprocating, electric motor driven air compressor for a vehicle. A detection component can be configured to detect a stall condition for a reciprocating compressor based on a force from compressed air being compressed into a reservoir of the reciprocating compressor. Based upon the detected stall condition, a controller can reverse direction or increase torque to alleviate the stall condition. In the reverse direction mode, the controller component can change a direction of a piston rotation. In the torque increase mode, the controller increases a number of poles for the motor, a line voltage, or a volt/hertz.

What is claimed is: 
     
         1 . A method, comprising:
 removing power from or reducing power to a motor coupled to a reciprocating compressor;   reversing a phase sequence of the motor to force a recompression of a piston of the reciprocating compressor; and   detecting at least one of a reverse stall or a start of the reciprocating compressor while in a reverse direction.   
     
     
         2 . The method of  claim 1 , further comprising reversing a torque direction of the motor to accelerate the piston past a Bottom-Dead-Center (BDC) position based on the detected reverse stall. 
     
     
         3 . The method of  claim 2 , further comprising accelerating the compressor past the BDC position with at least one of a torque of the motor or a pneumatic force on the piston to overcome a force from compressed air being compressed into a reservoir of the reciprocating compressor. 
     
     
         4 . The method of  claim 1 , further comprising driving the compressor in the reverse direction for a duration of time based on the detection of the start of the compressor. 
     
     
         5 . The method of  claim 1 , further comprising reversing a phase direction of the motor after the start of the compressor for a duration of time. 
     
     
         6 . The method of  claim 5 , further comprising returning a stuck loaded control magnet valve (CMV) or an un-loader valve based on the start of the compressor. 
     
     
         7 . The method of  claim 5 , further comprising returning a stuck loaded control magnet valve (CMV) or an un-loader valve based on elevation of a pressure of a reservoir due to the start of the compressor. 
     
     
         8 . The method of  claim 1 , further comprising detecting a stall condition to initiate the reversing of the phase sequence, wherein the stall condition is based on at least one of a control magnet valve stuck failure, a leakage on a high pressure cylinder discharge valve of the compressor, a high pressure cylinder un-loader valve stuck failure, or a low pressure cylinder un-loader valve stuck failure. 
     
     
         9 . The method of  claim 1 , further comprising increasing a torque to start the motor of the compressor with at least one of a pole switching, a line voltage increase, or a volt/hertz increase. 
     
     
         10 . The method of  claim 9 , further comprising increasing the torque to start the motor in at least one of a forward direction of the piston or the reverse direction of the piston. 
     
     
         11 . The method of  claim 9 , further comprising increasing the torque with a selection of a first pole mode to a second pole mode. 
     
     
         12 . The method of  claim 11 , wherein the first pole mode includes a first number of poles and the second pole mode includes a second number of poles in which the second number of poles is greater than the first number of poles, and further comprising detecting a stall condition based on at least one of a compressor speed, a motor current, or a measured pressure signal. 
     
     
         13 . A system, comprising:
 a compressor operatively connected to an electric motor, wherein the compressor includes a reservoir configured to store compressed air; and   a detector component that is configured to detect a stall condition of the compressor;   a controller that is configured to control the following based on the detected stall condition:
 removal of power from the motor of the compressor; 
 reversal of a phase sequence of the motor to force a recompression of a piston of the compressor; and 
 detection of at least one of a reverse stall or a start of the compressor while in a reverse direction as the piston moves to a Top-Dead-Center (TDC) position. 
   
     
     
         14 . The system of  claim 13 , wherein the compressor is a reciprocating compressor with a bi-directional drive system that drives the piston in a forward direction and the reverse direction. 
     
     
         15 . The system of  claim 13 , wherein the controller is further configured to:
 control reversal of a phase direction of the motor to accelerate the piston past a Bottom-Dead-Center (BDC) position based on the detected reverse stall; and   control acceleration of the compressor past the BDC position with at least one of a torque of the motor or a pneumatic force on the piston to overcome a force from compressed air being compressed into a reservoir of the reciprocating compressor.   
     
     
         16 . The system of  claim 13 , wherein the controller is further configured to control at least one of the following:
 a drive of the compressor in the reverse direction for a first duration of time based on the detection of the start of the compressor; or   a reversal of a phase direction of the motor after the start of the compressor for a second duration of time.   
     
     
         17 . The system of  claim 13 , wherein the controller is further configured to increase a torque to start the motor of the compressor by selecting a number of poles used by the motor from a first number to a second number, wherein the second number is greater than the first number. 
     
     
         18 . The system of  claim 13 , wherein the controller is further configured to control an increase to at least one of a line voltage or a volt/hertz to change a torque for an engine start of the compressor. 
     
     
         19 . A system, comprising:
 means for detecting a stall condition for a reciprocating bidirectional compressor based on a force from compressed air being compressed into a reservoir of the reciprocating bidirectional compressor;   means for removing power from a motor of the reciprocating bidirectional compressor;   means for reversing a phase sequence to the motor to force a recompression of a piston of the reciprocating bidirectional compressor; and   means for detecting at least one of a reverse stall or a start of the reciprocating bidirectional compressor while in a reverse direction as the piston moves to a Top-Dead-Center (TDC) position.   
     
     
         20 . A method to accommodate a failure to start a reciprocating air compressor due to a high starting torque associated with wear or failure of a component or system, comprising:
 detecting a stall condition for a reciprocating compressor based on at least one of a compressor speed, a motor current, or a measured pressure signal; and   increasing a torque to start the motor of the compressor with at least one of a pole switching, a line voltage increase, or a volt/hertz increase.