Steady-state theory of the amplidyne generator

The fundamental steady-state theory of the amplidyne generator is presented in this paper together with methods for calculating the characteristics of the generator from the machine constants. Experimental data obtained on a test machine are compared with calculated results to show the accuracy of the methods and to substantiate the theory. The effects of such factors as brush losses, commutation, and overcompensation and undercompensation on the operation of the generator are explained. Overcompensated and undercompensated machines are treated from the standpoint of both steady-state operation and electrical stability. Methods are given for the determination of the machine constants from open-circuit and short-circuit tests performed on the machine. This method offers the advantage that the machine constants so determined apply for actual conditions of operation and need not be modified to include the effects of such factors as brush and commutation losses, eddy currents, and hysteresis.