AC drive technology for locomotives

The author describes the use of GTO (gate turn-off) thyristors and microprocessor technology in connection with three-phase AC drive engineering for locomotives. The high power ratings of these devices, combined with efficient evaporation-bath cooling methods, have reduced the size and weight of the necessary powerful onboard converter equipment; AC drives are thus continuing to gain acceptance for traction applications. Examples that are given include Amtrak´s new diesel electric locomotives, the high-speed trains of the German Federal Railways, and the new high-performance locomotives of RENFE, the Spanish State Railway