DEVELOPMENT OF CROSS-INDUCTIVE CABLE FOR TRAIN LOCATION DETECTION IN THE SUPERCONDUCTING MAGLEV TRAIN CONTROL SYSTEM

摘要

We have developed a cross-inductive cable which serves to detect precisely the current location of a train on the superconducting Maglev railway. In the cross-inductive cable, six paired wires each composed of a twisted and a parallel portions repeated at fixed intervals are arranged so as to be able to detect the train location by calculating the voltages induced to the parallel portions from the signals transmitted from the on-board antennas of the train. The train is levitated and driven forward by the repulsive and attractive forces of the propulsion and levitation coils in the track called "guideway" and the superconducting magnets installed to the train. Train control is effected by the frequency and phase of the electric current applied to the coils, so it is necessary to detect the train location with high accuracy. As the cross-inductive cable is laid with high tension to prevent its expansion and contraction by the wind pressure from the train traveling at high speed as well as by temperature changes, mechanical strength and length accuracy under high tension become also important. The cross-inductive cable that meets these specifications was laid on the Yamanashi Maglev Test Line, and various running tests have been conducted with good results.