Dynamic modeling and control of a capacitor coupled dc-dc converter

Capacitor coupled dc-dc converter capable of arbitrary high voltage transformation has been recently introduced. The converter consists of a high frequency inverter feeding several rectifiers in parallel through capacitor coupling. The output voltages of the rectifiers are series connected to feed a high voltage dc load. This paper presents a simplified averaged equivalent circuit model for this converter operating in discontinuous conduction mode, along with a detailed dynamic model useful for designing regulators. The averaged equivalent circuit is used to develop a small signal dynamic model valid at a steady state operating point. The small signal model is used to develop the frequency response transfer functions of the converter. The control-to-output and input-to-output transfer function are used to design a controller with excellent dynamic response. The converter and controller model are validated using simulation results.