Series connection of power switches in high input voltage with wide range power supply for gate driving application

In high power systems design an important issue is to provide low voltages, in the range of tens of Volt, tapping from high voltage input line, which is usually in the range between hundreds of Volt to kilovolt, by means of switching power supplies. Low voltages are needed to supply logic control systems and power semiconductors driving the applications. The supply system has to deal, consequently, with both wide input voltage range and electrical insulation. The evaluation of the operative conditions of a driving system for IGCT devices, used in a transmission system application with wide input voltage range, is described. The design of a 100W supply converter is shown considering all the issues related with the series connection of power devices and the needs of insulation. Converter design, modeling and experimental results are shown together with the evaluation of the efficiency of the proposed solution.