Fault Diagnosis in Three-Phase Thyristor Converters Using Microprocessor

A microprocessor-based fault diagnosis scheme is presented for a three-phase fully controlled converter. In addition to the monitoring of the faults, the system also has the provision for a microprocessor-based firing scheme and a feedback-current control loop which provides protection against short circuit across the load terminals. The scheme has been experimentally tested. The osciliograms of some important waveforms are presented.