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This article describes the compact solid-state Marx modulator (SSMM) with a fast rising time and a short pulsewidth based on the modular structure. By stacking of the TO-263-7 packaged silicon carbide mosfets having high voltage and fast switching capabilities, the designed circuit consists of three components, including the Marx capacitor, an on switch for applying pulse to the load, and an off switch to pull down the pulse. The off switch connected in parallel with load is chosen as a mosfet instead of a diode that is used in the conventional Marx generator. Because the off switch provides a discharging path for the stored energy on the parasitic capacitance, it is highly related to the fast falling time. In order to provide complementary driving signal and power for on/off switches, the simple control algorithm with a minimum component count and a reliable drive circuit against the noise are proposed. In addition, the synchronization of all the gate signals and a compact configuration for minimizing the stray inductance are essential to shorten the rising, falling, and pulsewidth. Based on the proposed circuit, the following specifications of the developed SSMM are achieved: the output voltage of 10 kV, the pulsewidth of less than 50 ns, and the rising and falling times of less than 15 ns. [ABSTRACT FROM AUTHOR]

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]

This paper describes a bipolar pulsed power supply for strategic mineral exploration. Depending on the operating conditions, the bipolar pulsed power supply is capable of delivering the required high voltage and low current or low voltage and high current when operated, respectively, in either the grounded dipole mode or the loop mode. Based on a 500-V 12.5-A unit module, series and parallel connections of four modules are configured to satisfy both the grounded dipole mode (2000 V) and the loop mode (50 A), respectively. A unit module comprising an LCC resonant converter and a full-bridge-based bipolar pulse-switching unit is designed. In order to achieve high power density, the leakage inductance of the transformer is used as a resonant inductor in place of an external inductor. Accordingly, the resonant tank parameters are designed to give the resonant current a trapezoidal shape to reduce conduction loss and provide high efficiency. In addition, a simple gate-driving algorithm that uses the repetitive short pulse to cover the frequency range from dc to 8 kHz is proposed to allow the compact design of a minimized gate transformer. In this paper, the detailed design of the resonant circuit and the transformer of a unit module is described, and the operation is verified through simulation and experimental results. Finally, the developed LCC resonant converter achieves the maximum efficiency of 95%, the maximum power factor of 0.96, and a high power density of 806.5 W/L. [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]

This paper presents the design and experimental results of the 36-kW pulsed-power supply for the xenon flash lamp. The continuous conduction mode series-parallel resonant converter is modified. This means that not only the few hundred kilohertz of high switching frequency is introduced to replace the resonant inductor with the leakage inductor of transformer but also the high output current is accomplished by using three-phase delta-connected transformers. In addition, the snubber capacitor of the inverter switches and the power factor correction module is both omitted in the compact structure. Although these main components have changed, the efficiency and power factor of the rated dummy load reach 96% and 0.96%, respectively. Within 36-kW average power, the proposed pulsed-power supply can generate as versatile combination of output pulse. For example, it can generate 20-ms pulse with 1-Hz repetition rate or generate 1-ms pulse with 20-Hz repetition rate. The used insulated gate bipolar transistor is protected from the turn-OFF peak voltage by the snubber circuit, and the effect of the snubber circuit is shown at the actual load condition. [ABSTRACT FROM PUBLISHER]