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This paper proposes an active resonance circuit based on multiple series gaps (MSG) with voltage-dividing network and self-charging trigger device. The working principle of active resonance circuit, MSG, and triggering device is described in detail. To determine the optimal parameter setting of MSG, the effects of the voltage frequency, equalizing resistance, and voltage-dividing capacitance on the voltage distribution of MSG are analyzed by simulation. To realize the interrupting process of short fault current and determine the operation requirements of the main devices of precharge direct current (dc) circuit breaker, a simulation model of interrupting short fault current is performed. Furthermore, an experiment of four-series gaps is presented to verify the turn-on characteristic of the MSG and an experiment of artificial current zero is set up to testify the feasibility of the active resonance circuit. The simulation and experimental results show that the active resonance circuit proposed in this paper can generate an artificial zero current and is suitable for precharge dc circuit breaker. [ABSTRACT FROM AUTHOR]

A 700-kA gas switch with graphite electrodes for pulsed power supply module has been developed. This paper describes the design, construction, and testing of the high-current gas switch and its trigger system. The two-electrode gas switch is selected, which suffers high peak and fast rise time currents. The trigger generator based on resonant charging of a pulse transformer is constructed to trigger the gas spark. An electrodynamic force model of switch electrodes is established. The electrodynamic force of connecting wires is also calculated. By comparison of the mechanical strengths of polyformaldehyde, epoxy, and fiber-reinforced plastic (FRP) rods, where FRP rods are selected as switch rods, the experimental results show that the mechanical strength of the switch increases by 200%. Extensive electric testing has proven the operating parameters of the switch and its trigger system. The experimental results show that the measured discharge current waveform is demonstrated to be over a 700-kA peak current and a 500- \mu \texts pulsewidth. The transfer charge per shot is more than 500 C. [ABSTRACT FROM PUBLISHER]

Two-electrode graphite spark gap switch (TGSGS) is used as the main discharge switch and triggered by a reliable trigger generator in pulsed power conditioning system (PPCS). There would be 108 energy modules in PPCS working at the same time. The reliable operating and jitters of the trigger generators will have impact on the PPCSs performance. In this paper, the working modes of the TGSGS are discussed and the performance of trigger generators in PPCS is tested and presented. A protection strategy of the trigger generator in PPCS is introduced, and effect of the blocking capacitor on the trigger pulse transmission is analyzed and tested. The protection strategy of the trigger generator based on blocking capacitor and fuse can effectively prevent the energy anti-irrigation failure when the pulse transformer core saturated. The blocking capacitor has some effect on the trigger pulse transmission, and has the larger capacitance, getting the higher peak amplitude on the cathode of the TGSGS. It is tried to discuss the working characteristics of the thyristors, and proposes a selection reference of the thyristors in this and other similar applications. The combination of analysis and measurement would be useful for the selection of thyristors and other components. [ABSTRACT FROM PUBLISHER]

Fe-based nanocrystalline (FE-N) cores are widely used in pulsed-power and power electronic systems. In this paper, FE-N cores with high and low residual flux were tested and compared under single impulses. The loss density and permeability of the two FE-N types are evaluated in the usable flux swing range of \(\sim 0.0\) –1.4 T, and a range of magnetization rates of \(\sim 1.0~\mu \) s–6.0 T/ \(\mu \) s. When the loss density and average relative permeability are evaluated for magnetization from initial point to positive saturation based on the initial magnetization curves, the FE-N with low residual flux has lower loss density and larger average relative permeability than the one with high residual flux under low magnetization rates. The loss density and average relative permeability of the two FE-N types are almost the same values under high magnetization rates. The application of the measured results in magnetic switch design and performance analysis is presented. The presented results of the two FE-N cores can be aided in the practical magnetic designs of magnetic switches, pulse transformers, and inductors, but not restricted to those. [ABSTRACT FROM PUBLISHER]

Starting from the updated requirements of an advanced laser system, a switch–trigger system for a 2.0-MJ pulsed power supply (PPS) module is developed. This paper discusses the design, construction, and testing of this switch–trigger system. The two-electrode construction for the spark gap switch is selected because of its superiority in terms of long working life, high peak currents, and fast rise time of currents. The trigger generator based on resonant charging of a pulse transformer is constructed. A magnetic isolator and a pressure controller are the auxiliary equipment of this system. In the section based on mathematical principles, the equations of the lifetime and stability of this spark gap switch with graphite electrodes are given. These expressions can be regarded as the design basis of the same type of switch. As for the trigger generator, the analysis states that an appropriate ratio can be obtained when using the resonant charging based on a core-type pulse transformer. The charging time is dependent on the leakage inductance and the capacitance of the primary and secondary capacitors. Extensive testing proves the operating parameters of the switches and the trigger generator. The measured discharge current waveform of the 2.0-MJ capacitive PPS module is demonstrated to be over 500 kA peak current and 500 \mus pulse width. The life test proves that the switch–trigger system can support more than 200 kC transfer charge. By replacing the electrodes, the lifetime of this switch can be extended furthrer. [ABSTRACT FROM PUBLISHER]

In this paper, starting from the project requirements, a 1.2-MJ pulsed power supply (PPS) module for a high-power laser system has been developed. The main circuit of this module consists of a high energy density capacitor bank, a spark gap switch, a magnetic switch, a trigger generator, and a load subsystem. Due to the superiority in the stability and service life, the two-electrode construction for the spark gap switch, high peak currents, and rise time of the currents is selected. Since a two-electrode spark gap switch has no separate trigger electrode and must be directly overvolted by the trigger generator, a small Marx generator has been designed and constructed for the advantage of the proven compactness and electrical performance. The effect of the magnetic switch represents a couple of functions. One is to block the triggering pulse produced by the Marx generator. Another is to permit the discharging current coming from the main capacitor bank. Finally, the measured discharge current waveform of the 1.2-MJ capacitive PPS module is demonstrated to be over a 300-kA peak current and a 500- \mu\s pulsewidth. Moreover, the life test has proved that the switch–trigger system can support more than 1500 discharging processes. [ABSTRACT FROM AUTHOR]