Failed fuse detector and detecting method for rotating electrical equipment

摘要

A method and arrangement of apparatus is provided for remotely and selectively determining the existence of a failed fuse in the rectifier circuit of a brushless exciter rotor. A current transformer is disposed about each fuse in such a way that uses the conductor which carries current to the fuse as the primary winding of the current transformer. A light emitting diode is connected in series with the secondary winding of the current transformer. The emitted light, indicating a current flow through the fuse, is sensed by a stationary photodetector. This method senses the existence of a current flow through the exciter fuses and thereby positively determines each fuse that has not failed. Electronic circuitry is used to synchronize the detection operation with the rotation of the brushless exciter rotor so that each fuse is inspected at a time when it is expected to be carrying its maximum current. Since this method looks for the existence of current through each fuse, it operates in a failsafe manner.