Transient-Voltage Characteristics of Silicon Power Rectifiers

The behavior of ten types of silicon rectifiers under transient voltages was studied experimentally. The steady-state peak reverse voltage (PRV) ratings of these rectifiers were from 300-1200 V, and the half-cycle average current ratings were from 25-300 A. The study shows that, at least for the samples tested, the transient-voltage withstand capability of a silicon rectifier does not have any correlation with its PRV rating. A silicon rectifier may be damaged by a transient voltage lower than its PRV rating while it is carrying current in the forward direction. The transient-voltage withstand capability can also be widely divergent for different types of rectifiers of the same PRV rating. It is proposed that the transient-voltage withstand capability of each type of silicon rectifier should be specified along with its steady-state PRV rating.