Method for monitoring and controlling traction motors in locomotives

Abstract

The present invention is directed to a locomotive comprising energy storage units, such as batteries, a prime energy source, such as a diesel engine, and an energy conversion device, such as a generator. The locomotive comprises one or more of the following features: a separate chopper circuit for each traction motor and a controller operable to control separately and independently each axle/traction motor.

1 - 20 . (canceled)  
     
     
         21 . A method for addressing non-synchronous wheel slippage, comprising: 
 providing a plurality of traction motors, each of the plurality of traction motors being independently coupled to and driving at least one wheel;    detecting an operating characteristic of each of the plurality of traction motors;    determining that the at least one wheel corresponding to a first traction motor is experiencing wheel slippage; and    in response to the determining step, reducing power supplied to the first traction motor for a selected period of time while continuing to provide power in excess of the reduced power to the remaining traction motors.    
     
     
         22 . The method of  claim 21 , wherein the determining step comprises: 
 determining that the operating characteristic of the first traction motor has a predetermined relationship with an operating characteristic setpoint.    
     
     
         23 . The method of  claim 22 , wherein the operating characteristic is at least one of a corresponding operating speed of each of the plurality of traction motors and a corresponding electrical current supplied to each of the plurality of traction motors and further comprising: 
 comparing a detected operating characteristic detected for each of the traction motors to the operating characteristic setpoint and wherein, when the detected operating speed has the predetermined relationship with the operating characteristic setpoint, the at least one wheel of the corresponding traction motor is determined to be experiencing wheel slippage.    
     
     
         24 . The method of  claim 22 , wherein the reducing step is performed until the detected operating characteristic for the first traction motor no longer has the predetermined relationship with the operating characteristic setpoint.  
     
     
         25 . A controller operable to perform the steps of  claim 21 .  
     
     
         26 . A system for addressing non-synchronous wheel slippage, comprising: 
 a plurality of traction motors, each of the plurality of traction motors being independently coupled to and driving at least one wheel;    a plurality of sensors operable to sense an operating characteristic of each of the plurality of traction motors, wherein each of the sensors corresponds to a traction motor; and    a controller operable to determine that the at least one wheel corresponding to a first traction motor is experiencing wheel slippage and, in response thereto, reduce a level of power supplied to the first traction motor for a selected period of time while continuing to provide levels of power in excess of the reduced power to the remaining traction motors.    
     
     
         27 . The system of  claim 26 , wherein the controller is further operable to determine that the operating characteristic of the first traction motor has a predetermined relationship with a speed set point.  
     
     
         28 . The system of  claim 27 , wherein the controller is further operable to compare a detected operating characteristic detected for each of the traction motors to the operating characteristic set point and, when the detected operating characteristic exceeds the operating characteristic set point, determine that the at least one wheel of the corresponding traction motor is experiencing wheel slippage.  
     
     
         29 . The system of  claim 26 , wherein the controller is operable to reduce the level of power supplied to the first traction motor until the at least one wheel of the first traction motor is no longer experiencing slippage.  
     
     
         30 . The system of  claim 26 , wherein the controller is operable to increase the level of power supplied to the first traction motor when the at least one wheel of the first traction motor has a detected operating speed in excess of the speed set point.  
     
     
         31 . The system of  claim 26 , wherein the operating characteristic is a corresponding electrical current supplied to each of the traction motors.