Pulsed Power Supply Module Research Articles

Development of a Capacitor Bank-Based Pulsed Power Supply Module for Electromagnetic Induction Coilguns

This paper presents some discussions and findings related to the development of the capacitor bank-based pulsed power supply module (PPSM) for an electromagnetic induction coilgun (EIC). Three PPSMs were designed for a three-stage EIC to launch a 21.68-kg projectile at a minimum velocity of 20 m/s. The energy of the PPSM in the first, second, and third stages was 200, 100, and 100 kJ, respectively. Two light-triggered thyristors (LTT) were used as the main switches of the module. The synchronous behaviors of the series LTT, dump circuit, laser diode driver circuit, and protection scheme are analyzed and discussed. The PPSM was built and tested as an EIC system. The simulation results of the PPSM were in agreement with the experimental results. The peak current was about 42 kA at a maximum voltage of 10 kV as in the simulation. The maximum current in the 4-kV launch experiment was 16.47 kA. The velocity of the projectile was more than 25 m/s, which is consistent with the design goal.

Simulation of the Pulsed Power Supply Module Based on Electromagnetic Structure Coupling

It is important to analyze the electromagnetic coupling characteristics in pulsed power supply (PPS) during the design, and electromagnetic force analysis is becoming more and more important with the development of large capacity and miniaturization of PPS module. In this paper, the magnetic force on the metal structure affected by the pulsed electromagnetic field of the reactor is analyzed and calculated by the means of the finite-element code ANSYS. The results show that the electromagnetic force on the metal structure near the reactor is about ten times that of other parts. The eddy current distribution is calculated by the electromagnetic coupling simulation while the stress on the metal frame is analyzed by the electromagnetic structure coupling simulation. The breaking point assumed to be the weakest point in the structure. The weakest point in the structure is indicated by structural stress simulation. The electromagnetic force is reduced by cutting off the main induce loop through simulation, and the eddy current is measured by experiments.

Study on Graphite-Electrode Gas Switch Applied for Pulsed Power Supply With a 700-kA Peak Current

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- $\mu \text{s}$ pulsewidth. The transfer charge per shot is more than 500 C.

Simulation of Electromagnetic Force Between Pulsed Inductor and Internal Structure of Power Supply Module

With the development of electromagnetic launch (EML) technology, the pulsed power supply (PPS) module applied in EML needs to be smaller, lighter, and more compact. Electromagnetic force (EMF) is one of the most serious problems when PPS module works with high current. In this paper, we study the PPS module used in EML technology. The pulsed inductor model is built based on structure characteristics. The distribution of current density in the inductor during discharge is analyzed. The finite element analysis software is used to simulate and analyze the characteristics of the induction current and the EMF. The simulation model is composed of inductor and metals structures. The EMF laws are put forward by simulation of different shaped metals at different positions. By analyzing the distribution of the eddy current and EMF on the metal conductors at different positions, the EMF laws between the inductor and metal conductors in PPS module are presented in this paper.

Development of a Long-Lifetime Spark Gap Switch and Its Trigger Generator for 2.0-MJ Capacitive Pulsed Power Supply Module

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 ${\mu{\rm s}}$ 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.

2.0 MJ脉冲功率源的500 kA气体开关系统

A switch-trigger system for a 2.0 MJ pulsed power supply module has been developed. This paper discusses the design, construction and testing of this switch-trigger system. In the section about the mathematical principles, the equations of the lifetime and stability of the spark gap switch and its trigger generator are given. Extensive testing has proved the operating parameters of the switch-trigger system. The measured discharge current of the 2.0 MJ capacitive pulsed power supply module is demonstrated to be over 500 kA and the transfer charge per shot is over 150 C. The switch trigger system can support more than 200 kC transfer charge, and it can support simultaneous operation of 20 pairs of xeon flash lamps in theory. Moreover, the lifetime of this switch can be extended by replacing the graphite electrodes adopted.

Design, Construction, and Testing of Switches and Trigger Generator for 1.2-MJ Capacitive Pulsed Power Supply Module

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-μs pulsewidth. Moreover, the life test has proved that the switch-trigger system can support more than 1500 discharging processes.