A new method for the predetermination of the load characteristics of synchronous motors

The methods used hitherto for the determination of synchronousmotor and alternatorload-characteristics are similar, and depend on the estimation of the m.m.f.´s and fluxes underload conditions. This is, however, difficult to do with accuracy, owing to saturation, leakage and the different reluctances of the magnetic paths. The paper shows that tests can be performed at low speeds to reproduce exactly the m.m.f. and flux conditions which occur in a synchronous motor at normal speeds and loads. The errors inherent in previous methods are thereby avoided, enabling the synchronousmotor characteristics to b predetermined with a high degree of accuracy. The method described is applicable to cylindrical-rotor and salientpole machines.