Abstract: A saturable reactor diode snubber assembly is provided for use witha brushless excitation system. The diode snubber provided includes a thin film member composed of a saturable magnetic material. The magnetic material is saturated for a large percentage of the current cycle of each pase of the ac exciter. When the current approaches zero and the diode approaches reverse recovery, the magnetic film member of the present invention comes out of saturation and turns linear increasing overall exciter inductance and decreasing current fall rate, thereby reducing reverse recovery peak current and diode stored energy. This in turn reduces the effects of voltage spikes normally experienced during diode reverse recovery. The magnetic material is used at a predetermined thickness such that a desired result is obtainable. One embodiment of the invention involves placing the magnetic material on the side of the armature slot wedge adjacent to the top coil.

Abstract: A method for nondestructively electronically detecting a short circuit in a conductor system which is composed of two parallel inductor groups connected together to form a selected current path when no short circuit exists, by the steps of: disposing a current probe at a selected location of the current path for sensing changes in the current flowing in the path at the selected location; and injecting a fast rate-of-rise current pulse into the path; and monitoring the response of the current probe to provide an indication of the existence of a short circuit.