Development of an Embedded Power Supply System for Thyristor Driver Powered from Cathode-Anode Voltage

The high-power thyristors require reliable power supply for their drivers. The implementation of galvanic isolation for medium voltage applications needs large dielectric gaps and clearances which makes solutions bigger and more expensive. This paper proposes to use cathode-anode voltage variation for the thyristors operated in controlled rectifiers. The additional series capacitors circuit is used to implement power supply for the driver to control the gate voltage and current with respect to cathode electric potential. The functional diagram the power supply is provided and the method for evaluation of the circuit parameters was developed. The simulation model was built, and simulation result showed the feasibility of the proposed solution.