Estimating the fall in generator voltage following an impact load

Abstract Equations have been derived for calculating the changes in voltage that occur at the terminals of an alternator following the sudden application of a load. The influence of saturation within the machine, at the instant of application and during the subsequent transient, on the performance of the machine is defined. Rules are outlined to accommodate saturation when applying the equations so that voltage changes can be calculated accurately whatever the initial and shock load conditions. The effectiveness of the equations and techniques outlined are demonstrated in tests on a micromachine model and on a practical alternator.