A theoretical and experimental study of the series-connected magnetic amplifier

The mathematical analysis of magnetic amplifiers is made difficult by the non-linear characteristic of the iron. By simplifying the problem (neglecting leakage reactance and assuming an ideal B/H characteristic) a solution can be obtained which shows that the steadystate and transient operation of an amplifier having one of the two basic circuits analysed, depend on only three dimensionless coefficients. This solution leads to simple semi-graphical methods of determining the steady-state current and flux waveforms, and the response to sudden changes in input; satisfactory agreement between experimental results and theory has been obtained. Improvements in core characteristics have led to a simplified method of designing amplifier windings, and by special circuits amplifier delays have been reduced in the ratio of about 10:1.