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Published in James D. Taylor, Introduction to Ultra-Wideband Radar Systems, 2020
David Platts, Oved S. F. Zucker, Iain A. McIntyre
The simplest pulsed power circuit is a capacitor being discharged into a load by a switch as shown in Figure 4.2A. (The inductive analog of this circuit in Figure 4.2B requires an opening switch, which is difficult to make because the inductor will raise the voltage across the switch to attempt to maintain current flow through the switch. The inductive storage circuit should be considered only in special cases, since it is not generally easy to implement at high voltages.) The simple capacitive discharge circuit is the subject of the first exercise in time-dependent circuits that most electrical engineering students tackle. The disadvantage of the circuit is that it produces an output pulse whose amplitude is only equal to the charge voltage. We can do a little better with the circuit in Figure 4.2C, where we use an inductor to ring the load capacitor up to almost twice the voltage of the supply (this happens when Cl < < Cs). However, with the circuit of Figure 4.2C, we pay a penalty in risetime as the inductor rings up to full voltage. The impedance of this circuit is also higher than that of the one in Figure 4.2A. The circuit of Figure 4.2A is limited in risetime only by the closing time of the switch and any stray inductance in the circuit. While this circuit is sometimes used directly, it is often seen driving a voltage multiplier such as a transformer.
Solutions for Power Quality Issues of Wind Generator Systems
Published in Mohd Hasan Ali, Wind Energy Systems, 2017
Capacitors are used in many AC and DC applications in power systems. DC storage capacitors can be used for energy storage for power applications. They have long seen use in pulsed power applications for high-energy physics and weapons applications. However, the present generation of DC storage capacitors sees limited use as large-scale energy storage devices for power systems. Capacitors are often used for very short-term storage in power converters. Additional capacitance can be added to the DC bus of motor drives and consumer electronics to provide added ability to ride voltage sags and momentary interruptions. The main transmission or distribution system application where conventional DC capacitors are used as large-scale energy storage is in the distribution dynamic voltage restorer (DVR), a custom power device that compensates for temporary voltage sags on distribution systems. The power converter in the DVR injects sufficient voltage to compensate for the voltage sag, such that loads connected to the system are isolated from the sag. The DVR uses energy stored in DC capacitors to supply a component of the real power needed by the load.
Study On Generation Of Pulsed High Current With Aluminum Electrolytic Capacitor
Published in B. Raneesh, Nandakumar Kalarikkal, Jemy James, Anju K. Nair, Plasma and Fusion Science, 2018
Pulsed power has a wide variety of application, which includes nuclear fusion research, food processing, particle accelerators, medical treatment, defence sector, etc. [4]. High-voltage and low-inductance capacitors are mainly used in pulsed power application. These energy storage capacitors are used in the generation of high-peak current (kA) [8]. High-voltage energy storage capacitors have a paper dielectric and extended foil electrodes. They are impregnated with castor oil and are suitable for singleshot and repetitive rate applications [6]. Percentage voltage reversals of these high voltage capacitors are generally 80%. On the other hand, aluminum electrolytic capacitors have relatively larger capacitance per unit volume but aluminum electrolytic capacitors with non-solid electrolyte have different sizes, capacitance, and at low voltages. They have capacitance values 0.1 μF to 2.7 F with voltages values ranging from 4 V up to 630 V. They have a wide range of applications in SMPS based power supplies like DC-DC converters, rectified DC voltage, frequency converters as DC link capacitors for drives, inverters, etc. [1]. Aluminum electrolytic capacitors are polarized capacitors. They have to be operated with DC voltage with correct polarity and if correct polarity is not maintained, it will cause explosion. These capacitors, due to high energy density and low voltage, it became suitable to be used with unidirectional semiconductor switches. An aluminum electrolytic capacitor can be used in a limited space application. A capacitive storage pulsed power system consists of a power supply to charge the capacitor bank, a switch, and finally a load [5]. The stored energy in the capacitor bank is discharged into the load to produce a high current pulse.
A Forward Analytic Model of Neutron Time-of-Flight Signals for Inferring Ion Temperatures from MagLIF Experiments
Published in Fusion Science and Technology, 2022
Colin Weaver, Gary Cooper, Christopher Perfetti, David Ampleford, Gordon Chandler, Patrick Knapp, Michael Mangan, Jedediah Styron
Pulsed power compresses electrical energy in space and time to produce short bursts of high power that generate high energy density conditions.3 The Z-Machine can convert 22 MJ of energy stored in 36 Marx generators to 3 MJ of energy deliverable to the center section load hardware in the form of ~100-Mbar drive pressures and ~26-MA currents.2 These conditions allow the Z-Machine to produce >1 MJ of X-rays, which also makes it the most powerful X-ray source in the world.4–6