Modeling and analysis of high frequency high voltage multiplier circuit for high voltage power supply

High frequency high voltage power supply has been widely applied in many industrial applications such as the medical X-ray machine and eletrostatic precipitators. As a part of the high frequency high voltage power supply, the electrical performances of the voltage multiplier circuit will influence the behaviors of applications like the X-ray machine such as the imaging quality. The electrical performances include the output voltage drop and voltage ripple, rise time and decay time of output voltage and power losses. In order to get high imaging quality of the X-ray machine and reduce damage to patients, the multiplier circuit is required to be designed with low output voltage drop and voltage ripple as well as fast respond time. This thesis concentrates on the investigation of the electrical performances of the Half-wave series Cockcroft-Walton(HWCW) voltage multiplier circuit. The operations in start-up process and steady state are explained in details and methods to evaluate the electrical performances are introduced. Significant parameters of the multiplier circuit that play a role in determining the electrical performances are investigated. Analysis of impact of the parasitic components on the electrical performances are carried out together with simulations. An analytical power loss model is developed in the thesis by deriviations of currents in the HWCW voltage multiplier circuit. At last, optimization of capacitance distributions are discussed and compared to provide methods when selecting the capacitance values in the circuit. The analyses in the thesis are verified by the simulation results in LTspice.