Design and analysis of a pulse-width-modulated power supply for charging a customized pulse forming network

Team Specialty Products, Inc., in collaboration with Sandia National Laboratories, has built a high voltage pulse modulator for the purpose of calibrating resistive and capacitive voltage dividers. In order to meet performance specifications and lower the cost of the overall system, a power supply was required that can charge a pulse forming network (PFN) in < 5msec at a pulse repetition rate of 5 Hz. The use of a DC power supply and a command charging circuit would meet the performance requirements but such components are costly. By using a pulse width modulation circuit operating at the incoming line voltage, a more cost effective solution was achieved. A customized power supply has been designed that utilizes both a microprocessor to control an insulated gate bipolar transistor (IGBT) and utility grade transformer to efficiently place the desired amount of charge into the PFN. This paper discusses the customized power supply design and an analysis of its performance.