Automatic disabling of unpowered locked wheel fault detection

Abstract

A method for detecting a locked wheel on a locomotive is disclosed. The locomotive may have a plurality of wheels, a traction system configured to drive the plurality of wheels, and a controller in communication with the traction system. The fraction system may have a fraction motor coupled to each of the plurality of wheels, a speed sensor associated with each traction motor, an inverter connected to each traction motor, and at least one current sensor associated with each inverter. The method may include the controller detecting an initial locked wheel condition based on signals received from the speed sensors, and the controller determining if the initial locked wheel condition is true based on signals received from the current sensors.

What is claimed is: 
     
         1 . A method for detecting a locked wheel on a locomotive having a plurality of wheels, a traction system configured to drive the plurality of wheels, and a controller in communication with the traction system, the traction system having a traction motor coupled to each of the plurality of wheels, a speed sensor associated with each traction motor, an inverter connected to each traction motor, and at least one current sensor associated with each inverter, the method comprising:
 the controller detecting an initial locked wheel condition based on signals received from the speed sensors; and   the controller determining if the initial locked wheel condition is true based on signals received from the current sensors.   
     
     
         2 . The method of  claim 1 , further comprising the controller disabling a fault annunciation if the initial locked wheel condition is determined to be false. 
     
     
         3 . The method of  claim 2 , further comprising the controller disabling the fault annunciation for a predetermined time period upon determination of the initial locked wheel condition to be false. 
     
     
         4 . The method of  claim 3 , further comprising the controller monitoring current feedback from the current sensors after disabling the fault annunciation. 
     
     
         5 . The method of  claim 4 , further comprising the controller determining the initial locked wheel condition to be true during the predetermined time period when the fault annunciation is disabled, and the controller enabling the fault annunciation upon determination of the initial locked wheel condition to be true. 
     
     
         6 . The method of  claim 4 , further comprising the controller determining the initial locked wheel condition to be false when the predetermined time period elapses, and the controller re-disabling the fault annunciation for a subsequent predetermined time period. 
     
     
         7 . The method of  claim 1 , further comprising the controller determining the initial locked wheel condition to be true when signals received from the current sensors indicate a stalled traction motor. 
     
     
         8 . The method of  claim 7 , further comprising the controller enabling a fault annunciation upon determination of the initial locked wheel condition to be true. 
     
     
         9 . The method of  claim 8 , further comprising the controller sending the fault annunciation to an off-board location via a communication system. 
     
     
         10 . The method of  claim 1 , further comprising the controller determining the initial locked wheel condition to be false when signals received from the current sensors indicate similar feedback between each of the traction motors. 
     
     
         11 . A system for detecting a locked wheel on a locomotive having a plurality of wheels, each of the plurality of wheels having a traction motor coupled thereto, each traction motor having an inverter connected thereto, the system comprising:
 a speed sensor associated with each of the traction motors, each speed sensor configured to detect a speed of the associated traction motor;   at least one current sensor associated with each of the inverters, each current sensor configured to detect a current of the associated inverter; and   a controller in communication with each speed sensor and each current sensor, the controller configured to:
 monitor signals indicative of a speed of each traction motor received from the speed sensors; 
 monitor current feedback associated with each inverter received from the current sensors; 
 compare the current feedback to the signals from the speed sensors; and 
 verify if one of the plurality of wheels is locked. 
   
     
     
         12 . The system of  claim 11 , wherein the current detected by each current sensor is an alternating current (AC) from the inverter to the traction motor. 
     
     
         13 . The system of  claim 11 , wherein the current detected by each current sensor is a direct current (DC) input into the inverter. 
     
     
         14 . The system of  claim 11 , wherein the controller is further configured to determine an initial locked wheel condition when a speed of one traction motor is zero while a speed of the other traction motors is nonzero. 
     
     
         15 . The system of  claim 14 , wherein the controller is further configured to determine the initial locked wheel condition is true when current feedback associated with the one traction motor is different from current feedback associated with the other traction motors. 
     
     
         16 . The system of  claim 15 , wherein the controller is further configured to determine the initial locked wheel condition is false when current feedback associated with the one traction motor is similar to current feedback associated with the other traction motors. 
     
     
         17 . The system of  claim 16 , wherein the controller is further configured to disable a fault annunciation when the initial locked wheel condition is determined to be false. 
     
     
         18 . The system of  claim 17 , wherein the controller is further configured to disable the fault annunciation for a predetermined period of time. 
     
     
         19 . The system of  claim 18 , wherein the controller is further configured to continue monitoring current feedback after the fault annunciation is disabled. 
     
     
         20 . A method for preventing fault annunciation of a false positive locked wheel condition on a locomotive, the locomotive having a plurality of wheels, a traction system configured to drive the plurality of wheels, and a controller in communication with the traction system, the traction system having a traction motor coupled to each of the plurality of wheels, an inverter connected to each traction motor, a speed sensor associated with each traction motor, and at least one current sensor associated with each inverter, the method comprising:
 the controller monitoring signals received from the speed sensors;   the controller determining an initial locked wheel condition based on the signals from the speed sensors;   the controller monitoring current feedback from the current sensors;   the controller determining the initial locked wheel condition to be false based on the current feedback; and   the controller disabling a fault annunciation of the initial locked wheel condition.