System and method for predicting mechanical failure

Abstract

A system and method for monitoring a motor of a vehicle system monitor operating conditions of the vehicle system and determine whether the operating conditions of the vehicle system match designated operating conditions. Responsive to determining that the operating conditions of the vehicle system that are monitored match the designated operating conditions, an electrical signature representative of an electric current supplied to the motor of the vehicle system is examined and damage to one or more of the motor of the vehicle system or a mechanical coupling of the motor to one or more of a wheel or axle of the vehicle system is identified based on the electrical signature that is examined.

What is claimed is: 
     
         1 . A method comprising:
 monitoring operating conditions of a vehicle system;   determining whether the operating conditions of the vehicle system match designated operating conditions;   responsive to determining that the operating conditions of the vehicle system that are monitored match the designated operating conditions, examining an electrical signature representative of an electric current supplied to a propulsion system of the vehicle system; and   identifying damage to propulsion system based on the electrical signature that is examined.   
     
     
         2 . The method of  claim 1 , wherein the operating conditions include at least one of a speed at which a motor of the propulsion system rotates and a torque generated by the motor. 
     
     
         3 . The method of  claim 1 , wherein the operating conditions include both a speed at which a motor of the propulsion system rotates and a torque generated by the motor. 
     
     
         4 . The method of any other clause, wherein the designated operating conditions include both a designated speed at which a motor of the propulsion system rotates and a designated torque generated by the motor. 
     
     
         5 . The method of  claim 1 , wherein the electrical signature includes a frequency domain spectrum of one or more electrical characteristics of the current supplied to the propulsion system. 
     
     
         6 . The method of  claim 5 , wherein the damage is identified responsive to determining that the electrical signature includes an increased magnitude at one or more fault frequencies associated with the damage to the propulsion system. 
     
     
         7 . A method comprising:
 monitoring operating conditions of a propulsion system of a vehicle system during a baseline time period;   monitoring one or more electrical characteristics of current supplied to the propulsion system during the baseline time period;   examining one or more electrical signatures of the propulsion system to identify at least one electrical signature having reduced variances in magnitude at one or more frequencies associated with damage to the propulsion system; and   determining one or more sets of designated operating conditions of the propulsion system based on the one or more electrical signatures that are examined, wherein the one or more sets of designated operating conditions are used to determine which of subsequently monitored electrical characteristics of the current are to be examined to identify the damage to the propulsion system.   
     
     
         8 . The method of  claim 7 , wherein the operating conditions include both a speed at which a motor of the propulsion system rotates and a torque generated by the motor. 
     
     
         9 . The method of  claim 7 , wherein the designated operating conditions include both a designated speed at which a motor of the propulsion system rotates and a designated torque generated by the motor. 
     
     
         10 . The method of  claim 7 , wherein the one or more electrical signatures includes a frequency domain spectrum of one or more electrical characteristics of the current supplied to the propulsion system. 
     
     
         11 . The method of  claim 10 , further comprising:
 subsequently determining whether additional operating conditions of the vehicle system match the designated operating conditions of at least one of the sets of the one or more designated operating conditions;   responsive to determining that the additional operating conditions of the vehicle system match the designated operating conditions of the at least one of the sets, examining an additional electrical signature of the current supplied to the motor; and   identifying the damage to the propulsion system based on the additional electrical signature that is examined.   
     
     
         12 . A system comprising:
 one or more sensors configured to measure operating conditions of a vehicle system; and   a controller configured to determine whether the operating conditions of the vehicle system match designated operating conditions, the controller also configured to examine an electrical signature representative of an electric current supplied to a motor of the vehicle system responsive to determining that the operating conditions of the vehicle system that are monitored match the designated operating conditions, wherein the controller also is configured to identify damage to one or more of the motor of the vehicle system or a mechanical coupling of the motor to one or more of a wheel or axle of the vehicle system based on the electrical signature that is examined.   
     
     
         13 . The system of  claim 12 , wherein the operating conditions include a speed at which the motor rotates. 
     
     
         14 . The system of  claim 12 , wherein the operating conditions include a torque generated by the motor. 
     
     
         15 . The system of  claim 12 , wherein the operating conditions include both a speed at which the motor rotates and a torque generated by the motor. 
     
     
         16 . The system of  claim 12 , wherein the designated operating conditions include a designated speed at which the motor rotates. 
     
     
         17 . The system of  claim 12 , wherein the designated operating conditions include a designated torque generated by the motor. 
     
     
         18 . The system of  claim 12 , wherein the designated operating conditions include both a designated speed at which the motor rotates and a designated torque generated by the motor. 
     
     
         19 . The system of  claim 12 , wherein the electrical signature includes a frequency domain spectrum of one or more electrical characteristics of the current supplied to the motor. 
     
     
         20 . The system of  claim 12 , wherein the controller is configured to identify the damage responsive to determining that the electrical signature includes an increased magnitude at one or more fault frequencies associated with the damage to the one or more of the motor or the mechanical coupling.