FROM THE IDEA OF THE THREE-PHASE CURRENT TECHNIQUE TO THE LOCOMOTIVE CLASS 120 - AN EXAMPLE OF A LONG-STANDING COOPERATION BETWEEN THE WEST GERMAN RAILROAD SYSTEM (DB) AND INDUSTRY

First applications of the three-phase current technique for electric traction in Germany date back to 1903. Only later was it possible to realize this technique by the combination of power electronics and the three-phase asynchronous motor fed with three-phase voltage of variable amplitude and frequency. A description is given of the early beginnings of the producer leading to testing of the prototype locomotives. The close and successful cooperation between producer and DB is pointed out.