A High Power Dynamically Flexible Pulse Width Radar Modulator

Stangenes Industries has developed an all solid state Marx type modulator for radar klystron applications with flexible pulse width control. The modulator can supply 90kV pulses with pulse widths from 2muS to greater than 100muS, with a pulse current of greater than 50A, and average power of 130kW. It can be operated in burst mode with dynamically changing pulse width, while maintaining a voltage stability of <0.2% (with duty factor < 3%). The modulator uses 6.5kV IGBTs to both charge and discharge the Marx configuration capacitors. A newly developed high efficiency resonant capacitor charging power supply is used to provide the power for the modulator and maintain the pulse to pulse voltage stability. The modulator can accommodate load arcing and is automatically redundant to insure high availability. The paper will delineate the unique design of the modulator and its performance into a radar klystron.