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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, a 25-kW bipolar pulsed-power supply for strategic mineral exploration has been described. A 500-V, 12.5-A unit module consisting of a highly efficient LCC resonant converter and a full-bridge-based bipolar pulse-switching unit is designed. The LCC resonant converter has a trapezoidal-shaped resonant current for reduced conduction loss. For achieving high power density, the leakage inductance of the transformer is used as resonant inductance without an external inductor. Moreover, the designed gate drive circuit based on the repetitive short pulse is proposed to operate the frequency range from dc to 8 kHz and reduce the size of the gate transformer. Four modules are connected in series and parallel in order to operate the power supply in either loop mode or grounded dipole mode. Depending on the load condition, the pulse power source capable of delivering the required high voltage and low current (2 kV, 12.5 A) or low voltage and high current (500 V, 50 A) is operated either in grounded dipole mode or loop mode, respectively. In order to satisfy the output voltage balancing of the four modules, the third wire is wound to compensate for the transformer of the LCC resonant converter. Finally, the design of the bipolar pulsed-power supply has been verified based on the experimental results of the field test. [ABSTRACT FROM AUTHOR]

Conventional power supply systems for xenon lamps have only limited applicability in sintering, because sintering needs to drive the lamp itself as well as enable instantaneous and strong discharge of voltage and current for generating intense light. This implies that, for sintering applications, a method should be developed that would enable instantaneous and strong discharge of energy. In this paper, we propose a new xenon lamp sintering system with an additional capacitor charger and bank. The proposed system features three power supplies. Two power supplies, called the trigger and the simmer, ionize gaseous xenon using a 23-kV trigger pulse output and sustain the ionized xenon gas using a 2.5-kW simmer power supply. The used trigger is also specially designed to conduct high current through its transformer, and it makes the proposed system an outstanding high voltage blocking capability. Another 36-kW power supply charges a 130-mF capacitor bank with a high-efficiency resonant converter. In addition, some components such as the simmer blocking diode and the trigger output capacitor are introduced, because combining different power supplies causes operational problems. These components are analyzed with some circuits that show its features, and finally, the validity of the suggested system was confirmed in two steps. First, the simmer power supply and the capacitor charger were tested for the rated operating performance by using a resistive load condition. As a result, the rated operation of the simmer power supply was confirmed under the 2.5-kW output condition, and the efficiency of the capacitor charger was found to be greater than 96% at the rated 36-kW rated load condition. In addition, a pulse discharge current of 900 A was also observed with the equivalent resistor load through a pulsed discharge experiment of the capacitor bank, which was charged at 1500 V. The trigger power supply, whose equivalent resistive load was difficult to realize, was experimented directly using the real xenon lamp to check the stable trigger operation of the xenon lamp at its 23-kV output pulse voltage. After the verification using the resistive load condition, the real operation and performance of the combined xenon lamp power supply system that includes three kinds of power supplies were finally tested and verified by using the actual xenon lamp as a total system. [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 describes the design and analysis of a 42-kW (14 kV, 3 A) high-voltage power supply for a 30-kW industrial magnetron drive. The design is based on a series resonant converter in discontinuous conduction mode (DCM) to take advantage of both the superior arc protection stemming from the current source characteristics and the high power density owing to the use of parasitic elements such as the leakage inductance in the high-voltage transformer. The detailed design procedure for the resonant tank and high-voltage transformer with respect to the input and output specifications is described on the basis of a simplified analysis of the DCM series resonant converter. Special considerations for designing high-power high-voltage power supplies are provided, such as series stacking of diodes for a voltage doubling rectifier and insulation between each winding of the high-voltage transformer. In addition, a comparative study using theoretical equations, simulation, and experimental results was carried out. This study yielded the output voltage and current characteristics at different switching frequencies and verified the advantages of this topology, such as arc protection without an additional protection circuit and high efficiency due to zero-current or zero-voltage switching. Moreover, the parallel operation of two converters with phase shifted gating signal is proposed to reduce the output current ripple and increase power capability for higher power magnetron drive. Additionally, the design considerations of two auxiliary power supplies (a filament power supply: 15 V, 150 A and a magnet power supply: 50 V, 5 A) are also provided and optimized for effective driving industrial magnetron. Finally, the developed power supply was tested with a 30-kW industrial magnetron, and the results prove the reliability and robustness of the proposed scheme. [ABSTRACT FROM PUBLISHER]