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Researchers and manufacturers of lithium-ion batteries (LIBs), electric-double-layer capacitors (EDLCs), and lithium-ion capacitors (LICs) have been able to produce devices with power densities previously thought to be impossible. As a result of their higher power density, these devices are able to source high currents to compact pulsed power loads. Though many pulsed power sources already exist which...
High-voltage (HV) ultrashort pulse technologies have found many applications in areas such as medicine, biology, food processing, environmental science and defense. Some applications are dependent on the pulse parameters such as duration, amplitude, shape, as well as the number of pulses applied and the frequency rate. Generators that can produce powerful electrical pulses with adjustable duration,...
Lightning parameters measurement of the transmission lines is the foundation of lightning protection research. It plays an important role in supplying the original accurate data to study the lightning characteristics, analyzing the reason for lightning accidents, and designing the insulation of the transmission line. In this paper, the distribution of the lightning transient electromagnetic fields...
Among the traditional lightning current monitoring systems, it is hard to ensure measuring lightning currents directly, expediently, accurately and safely at the same time. So aiming at solving the problem of measuring the lightning current on the overhead transmission lines, it is necessary to create a novel lightning current monitoring system based on the differential-integral loop which has been...
The design and realization of a nanosecond, high-voltage electric pulse generator for bioelectrical applications is reported in this paper. A Blumlein type architecture was adopted, with some modifications, and realized in a microstrip line configuration with meander-shaped conducting strips, and with ultra-fast, high voltage solid state switches. Three microstrip-lines have been realized in such...
We report on 2D particle-in-cell (PIC) simulations of electrical breakdown incorporating single-surface multipactor with background-gas ionization. The system for study is a semi-infinite, two-electrode Bergeron geometry with an angled dielectric in steady-state fields, with a background gas at variable low pressure. For pressures below a few tens of Pa (a few hundred mTorr), discharges are dominated...
Capacitor charging power supply (CCPS) is a developed technology that utilizes resonant converters topology for high power applications. This paper proposes new a capacitor charging power supply using leg-rotation control method within a phase-shifted PWM full-bridge dc/dc converter. The capacitor charging power supply was connected in series to increase output voltage. Also, the proposed system is...
In many pulsed power applications, high voltage and high frequency square pulses are needed. Traditional Marx type modulators based on solid-state switches often couldn't meet the requirements, especially on frequency and waveform. To solve the problems, a novel solid-state pulsed power modulator based on charging and driving by magnetic ring transformers is introduced in this paper. In order to obtain...
In this work, the electric discharges activity on non-uniformly polluted glass plane insulator model is investigated for increasing applied voltage levels up to flashover. The effect of pollution severity was simulated using pollution solution containing various kaolin concentrations. The polluted sample has a strip that is dry and clean which is parallel to the electrodes planes. Configurations with...
In this work, a powder tailored to fulfill the required conditions for field grading of HV applications was designed using a high-energy ball milling and annealing process. Excellent results in line with requirements were found, and show that this powder can be custom-made for the intended present and future applications. The different powders introduced here are based on aluminum (Al) and boron nitride...
Tumor cell apoptosis by using nanosecond pulsed electric fields (nsPEF) has a great potential in clinical tumor treatment. It is difficult to find the appropriate parameters of nsPEF which can induce substantial apoptotic tumor cells because of selectivity between apoptosis and parameters of pulse number and pulse duration. To obtain the optimum parameters of nsPEF which can achieve large proportion...
Very fast transient overvoltages (VFTO) may result in insulation failures inside or outside gas insulated switchgears (GIS), and most of them are caused by surface flashovers along insulating spacers according to operational experiences. For a good understanding of the discharge process produced by high voltage pulses with a fast rising time, an experimental study on spacer flashover under repetitive...
An all solid-state Marx modulator utilizing Insulated Gate Bipolar Translators (IGBTs) is capable of outputting pulses with variable pulse width, repetitive pulse frequency and varying voltage amplitude. But the relatively slow turn-on speed of IGBT with high current loads result in slow rise time of output pulses. If a magnetic switch (MS) is combined with an all solid-state Marx, it will be quite...
In ozone production using streamer discharges by pulsed power, the concentration of ozone is not high although ozone is produced with high efficiency. To improve ozone concentration, we studied the effects of electrode separation in a coaxial reactor using nanosecond pulsed power. We found that ozone concentration and yield increase with decreasing inside diameter of the outer electrode in the reactor...
The Electra pulsed power system at the Naval Research Laboratory is capable of supplying 16 kJ to a low impedance load within 140 ns, and it allows continuous operation of up to 5 pulses per second for several hours. Four laser triggered SF6 gas switches transfer the stored pulse forming line energy to the load. Each switch has a hold-off voltage of more than 1 MV and transfers a charge of 10 mC per...
A nonlinear lumped element transmission line (NLETL) that consists of a nonlinear LC ladder network whose capacitors are nonlinear and inductors are linear can be used to produce oscillating pulses. This article describes the implementation of an oscillating pulse generator based on such high voltage nonlinear capacitive lines (NLCL) using commercial-off-the-shelf (COTS) components. Instead of using...
This paper describes a novel MOSFET gate driver circuit design for pulsed power application. It is shown that MOSFET switching speed can be enhanced by using an energised inductor as a high current source in series with the gate terminal of a power MOSFET. This topology demonstrates switching speeds of less than 10ns for MOSFETs with high input gate capacitance. It is also shown that by increasing...
A high power resonant three phase switch mode power supply has been constructed at University of Wisconsin to drive a klystron tube. Utilization of a resonant transformer with loosely coupled secondaries allows generation of high boost ratios exceeding the turns ratio while providing high efficiency. Use of nanocrystalline iron cores provides high volt seconds while maintaining low loss at high switching...
To operate power transformers long-term, as well as ensuring their insulating reliability, adequate consideration must also be paid to the age-related decline in various insulating oil characteristics. Previous studies could roughly clarify the key components causing the insulating oil characteristics to decline by adding the components contained in field transformer insulating oil to oil with few...
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