An Analysis of Transients in Magnetic Amplifiers

Analytical expressions are developed for the envelope of the transient output current of a magnetic amplifier when the control voltage is varied. The magnetization curve of the core material is expressed in a convenient analytical form and the differential equations of the system are integrated under certain simplifying assumptions. The analysis applies to transients lasting a few cycles of the supply frequency, or longer; and experimental checks show good agreement within the range of transients specified above. The results are given in the form of dimensionless curves expressing the average flux density, average magnetizing intensity, and output currents as functions of time. Thus the influence of the core material and of factors of design upon the transient response of the amplifier are determined.