Excitation cct. for two sync. motors - has two thyristor switches separately supplying motor excitation windings from exciter

摘要

The excitation circuit for a synchronous motor set consisting of two motors on a common shaft, but of different speeds has an excitation machine supplying a rotary rectifier. A protective circuit is connected in parallel with the rectifier. The rectifier output is coupled via two main thyristors to each of the two motors excitation windings. Each of these excitation windings is bridged by a protective circuit, consisting of two anti-parallel thyristors and an RC shunt element. The anti-parallel thyristors connect each a main thyristor cathode to the junction between the excitation winding and the rectifier.