Design and Modelling of SRC Based Capacitor Charging Power Supply for High Power Klystron Modulator Using MULTISIM

Capacitor charging power supplies (CCPS) with series resonant converter (SRC) topology are being widely used in place of conventional high voltage dc power supplies in Klystron-modulators. The advantages include small size, zero current switching and wide load range operation. A model of CCPS is developed in MULTISIM/Pspice with features of controlling the repetition frequency(PRF) of discharging pulse forming network (PFN) and switching frequency of series resonant converter (SRC). Transient analysis simulation of the model is carried out in Pspice. The results show that model can charge a 0.282 μF PFN (6-section) capacitors from 0 to 24 kV in 1.11 ms at a PRF of 300 Hz. By operating the model at the maximum PRF data has been collected from other nodes of the CCPS circuit so as to determine the specifications of components required for the development. Further, components for developing CCPS have been selected based on these derived specifications. This MULTISIM model of CCPS is regularly used during different stages of development to verify the signals acquired, deduce reasons for any component failures. This model comes in handy during the development of such complex system reducing the time of development by reducing the iterations required for rectifying the design.