PROTECTIVE CIRCUIT FOR DIODE SWITCHING DEVICE

摘要

An electrical circuit supplying a load from a voltage source includes a switching device and a diode, and is to be protected from recovery current caused by polarity reversal of the diode during the operation of the switching device. The electrical circuit further includes a transformer having an excitation winding sensing the recovery current through the diode immediately after operation of the switching device, and a sink winding coupled to the excitation winding for inducing in the sink winding a reverse current corresponding to the current in the excitation winding. A unidirectional conducting device directs at least a portion of the reverse current from the sink winding back to the voltage source.