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This paper describes the circuit of a capacitor charger for a solid-state Marx modulator. A high-efficiency LCC resonant inverter is proposed for the simultaneous charging of many capacitors in parallel using a multistage transformer and rectifier. Using a high-voltage insulation cable, the charging loop, which represents the primary winding of transformer, is implemented to transfer the power from the resonant inverter to each stage. In addition to the simultaneous charging of separate capacitors, the advantages of the proposed circuit and structure include compact design and reliable insulation performance against high-voltage pulses. Based on the relevant approximation, the simplified analysis of an LCC resonant converter with a trapezoidal shape of resonant current is provided and a 50-kW high-voltage capacitor charger is designed for a 40-kV solid-state Marx modulator. The power stage, which consists of a transformer with four voltage-doubled rectifiers, is designed, and six power stages are configured for generating a pulse output of 40 kV. The detailed implementation of the multistage transformer and rectifier is presented in accordance with the design requirements of a high voltage modulator. Finally, the developed charger achieves 96% of the maximum efficiency and 0.96 of the maximum power factor. The experimental results verify that the proposed circuit and structure can be effectively used for a solid-state Marx modulator. [ABSTRACT FROM PUBLISHER]

This paper describes the design, implementation, and comparison of high-voltage capacitor chargers for a solid-state pulsed power modulator (SSPPM). The three different converter topologies are a series resonant converter operating at a discontinuous conduction mode with switching frequency control (SRC_DCM_SFC), a series resonant converter operating at a continuous conduction mode with phase shifted pulse width modulation control (SRC_CCM_PSPWMC), and a series–parallel resonant converter operating at the CCM with SFC (SPRC_CCM_SFC). On the basis of these converter topologies, 10\-kW\rm{average} high-voltage capacitor chargers are designed for the three types of SSPPMs, which have the following maximum output specifications: 1) SRC_DCM_SFC: 60 kV, 300 A, 3 kpps, and 50 \mus; 2) SRC_CCM_PSPWMC: 10 kV, 50 A, 50 kpps, and 10 \mus; and 3) SPRC_CCM_SFC: 40 kV, 150 A, 7 kpps, and 10 \mus. Although the pulse output specifications are different, it is worth comparing the resonant inverter topologies and the control methods from the viewpoint of the losses, control characteristics, and merits and demerits of the high-voltage capacitor chargers. From the analysis and investigation of the three resonant inverters, the design procedure, including the determination of the resonant tank parameters, is provided, which considers the design of the high-voltage capacitor charger. PSPICE simulation is used to elucidate the effects of the resonant tank structure and its parameters, and the resonant current waveform and losses of the Insulated Gate Bipolar Transistor are compared. Finally, experiments for each charger are performed under various load conditions, and the comparison results of the three capacitor chargers, including the conduction and switching losses, control characteristics, and overall efficiency, are discussed in this paper. [ABSTRACT FROM AUTHOR]