Transient Low Frequency Unsymmetrical Operation of Synchronous Machines

A complete analytical study of the sudden unsymmetrical short circuit of a synchronous machine is given. The method is to find the time constants and the eigenfunctions of the problem. The variation of the time constants, as affected by the external impedances, is shown. Curves of transient currents are computed and checked against experiment. Stress is on low frequency operation. All expressions are given in terms of the classical parameters of the machine, which may be known from classical tests. One of the main objectives of this paper is to prepare the analytical study of the inverter fed synchronous machine.