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This paper describes the design and implementation of a three-phase resonant converter with low ripple and high control accuracy. Based on a three-phase LCC-type resonant converter—which has advantages of low ripple, high-efficiency, and high-power density compared with a single-phase converter—a high-voltage power supply with low ripple (<0.1%) was designed. In addition to the general merits of an LCC-type resonant converter operating at continuous conduction mode—including soft switching, low conduction loss, and current source characteristics—the proposed scheme uses only one phase under a light-load condition by having different leg designs of the gate drive circuit and snubber parameters. This allows the design to overcome the operational constraints of the general LCC-type resonant converter. The distinctive design of the three-phase converter structure provides high efficiency and low ripple not only during rated operation, but also under light-load conditions. In order to analyze the high performance of the proposed scheme from no load to rated load, a PSPICE simulation was carried out. Comparison results with a conventional LCC-type resonant converter based on a single-phase structure are analyzed from the viewpoints of output ripple, losses, and operable load range. Using the proposed converter, a 20-kV, 20-kW high-voltage dc power supply design and implementation was presented with a superior gate drive circuit. Finally, the superiority of the proposed converter was verified through a simulation and experimental results. It was experimentally confirmed that the developed power supply achieves high performance in terms of efficiency (98%), operable load range (0.5–20 kV), and low ripple (0.05%), with a high power density. [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]

This paper presents the design and implementation of a 40-kV, 20-kJ/s high-voltage capacitor charger based on a series/parallel resonant converter. The inclusion of the parallel resonant capacitor component in this circuit results in the production of a trapezoidal resonant current, which reduces conduction loss. This capacitor is practically realized as a part of the balancing network of the high-voltage rectifiers in the secondary side of the circuit. Particular attention in this paper is paid to the high-voltage transformer, which must be carefully designed to provide the required functionality without negative impact on the resonant circuit. A PSpice simulation has been used to prove that the proposed control method for the circuit is valid. This is supported with the experimental results, which verify that the operation of the circuit is as expected and that the converter is able to meet all the design criteria with an efficiency of up to 96%. [ABSTRACT FROM PUBLISHER]

This paper proposes a flyback-circuit-based design of a trigger circuit for a high-power gas switch. By incorporating a flyback circuit in a high-power gas switch, it is possible to generate a high step-up ratio and high-voltage pulse by using a transformer. Furthermore, simple trigger circuit having the minimum possible number of components (transformer and switch) can be realized. When an inductor is used as an energy storage element, energy is stored as a current source, and thus, the element can operate reliably when low impedance exists between the trigger node of the switch after triggering. According to the fundamental operating principle of a flyback circuit, the proposed trigger circuit is designed considering the maximum trigger voltage and energy required for a high-power gas switch. To verify the proposed design procedure and feasibility of the trigger circuit, a compact trigger circuit (7.5 kV, 1.3 mJ/pulse) is simulated using the PSpice program and implemented. Based on this compact circuit, a trigger circuit (20 kV, 100 mJ/pulse) for a triggered vacuum switch (TVS) is developed, and the tests with an actual TVS (3.3 kJ) are carried out. [ABSTRACT FROM AUTHOR]

In this paper, the detailed design of an ion pump power supply is presented. The ion pump power supply was designed based on an LCC resonant topology with high switching frequency to take advantage of a smaller transformer for isolation. Because the proposed ion pump power supply has a 7-kV, 50-mA specification, high-voltage insulation is required. In order to secure insulation reliability, the power supply was designed with eight separate transformers that share primary turns. The spacing between the primary turns and secondary turns allows for increases in the leakage inductance and parasitic capacitance of the transformer. A compact design can be achieved using the parasitic component generated by the proposed design as the resonant parameters of the LCC resonant converter. In addition, based on a trapezoidal approximation of the LCC resonant converter, the resonant parameters are designed to have trapezoidal shapes of the resonant current in order to reduce conduction loss. Finally, the results of the experiment indicate that the developed ion pump power supply can be used effectively in high-voltage and low-current applications. [ABSTRACT FROM AUTHOR]