Anti-slip Readhesion Control without Speed Sensor for Electric Railway Vehicles

Abstract

Since the advent of railway vehicles with three-phase drive in the 1970s, power semiconductors used in electric railway vehicles have been changed from thyristors to GTO thyristors and IGBTs. As for traction motor control, vector control has come into wide use in place of slip frequency control and vector control without speed sensor is at a trial stage for commercial trains. Anti-slip and readhesion control of railway vehicles has greatly progressed by utilizing wheel axle speed information. Locomotives and electric multiple units with speed-sensor-less vector control in the future should have at least the same adhesion performance as that of the alternatives with speed sensor.
In this paper, a novel anti-slip readhesion control without speed sensor is proposed. By this method small wheel slips can be easily detected. Its performance is expected to be as high as that of the control with speed sensor. This paper enumerates the characteristics of wheel slip phenomenon and anti-slip control for railway vehicles, explains the running test results that show basics of anti-slip readhesion control with speed sensors, describes an outline of the novel anti-slip readhesion control without speed sensor, and verifies the basic functions by simulation.