Method for detecting locomotive traction motor speed signals using magnetoelectric sensors

摘要

#$%^&*AU2013263818A120140703.pdf#####ABSTRACT The invention provides a method which comprises recording triggering time of present and previous rising or falling edges of sensor pulse signals, obtaining present time difference ATm, frequency Fm= 1/ATm, and a present detection value of traction motor speed. When the locomotive operates in a traction or braking mode, current value Im of the traction motor is detected, and current average value Iavr, current imbalance degree Fim, and speed average value Navr of the traction motor is calculated. If Nm Navr x f and P-m Fmax continuously hold true for more than a preset number of times, R, it may determine that an m-th sensor is in a fault state. When the locomotive is in a non-traction and non-braking mode, if Nm Navr x r holds true more than a preset number of times, R, it may determine that the m-th sensor is in a fault state. For a non-fault m-th sensor, if Nm Nmc + A N is true, let Nnc = Nmc + A N; otherwise, if Nm Nmc - A Nm holds true, let Nmc = Nme - A N; otherwise, let Nme = Nm. A fault sensor can be removed, interference can be avoided and the real-time requirements for speed feedback when wheel slip or skid happens can be met. 8