Method and apparatus for detecting a failed thyristor

摘要

A method or system consistent with this invention for detecting if a thyristor failed open in an alternating current input phase of a load comprises measuring an instantaneous power delivered to the load during a cycle of the input; determining a peak power delivered to the load during the cycle of the input; calculating an average power delivered to the load during the cycle of the input; and determining if the thyristor failed open by comparing the magnitudes of the peak power and the average power.