W.S. Zaengl

Bio: W.S. Zaengl is an academic researcher. The author has contributed to research in topics: Electrical breakdown & High voltage. The author has an hindex of 3, co-authored 3 publications receiving 1020 citations.

High-voltage engineering: Fundamentals

Abstract: Introduction Generation of high voltages Measurement of high voltages Electrostatic fields and field stress control Electrical breakdown in gases Breakdown in solid and liquid bielectrics Non-destructive insulation test techniques Overvoltages, testing procedures and insulation coordination Design and testing of external insulation Index

Polymer Composite and Nanocomposite Dielectric Materials for Pulse Power Energy Storage

Abstract: This review summarizes the current state of polymer composites used as dielectric materials for energy storage The particular focus is on materials: polymers serving as the matrix, inorganic fillers used to increase the effective dielectric constant, and various recent investigations of functionalization of metal oxide fillers to improve compatibility with polymers We review the recent literature focused on the dielectric characterization of composites, specifically the measurement of dielectric permittivity and breakdown field strength Special attention is given to the analysis of the energy density of polymer composite materials and how the functionalization of the inorganic filler affects the energy density of polymer composite dielectric materials

Streamers in water and other dielectric liquids

Abstract: Experimental results on the inception and propagation of streamers in water generated under the application of high electric fields are reviewed. Characteristic parameters, such as breakdown voltage, polarity of the applied voltage, propagation velocities and other phenomenological features, are compared with similar phenomena in other dielectric liquids and in gases. Consequently, parameters that are expected to influence the development of streamers in water are discussed with respect to the analogous well-established models and theories for the related mechanisms in gases. Most of the data support the notion that an initial low-density nucleation site or gas-filled bubble assists the initiation of a streamer. Details of this theory are laid out explaining the observed differences in the breakdown originating from the anode versus the cathode locations. The mechanisms can also be applied to streamer propagation, although some observations cannot be satisfactorily explained.

Assessment of Eco-friendly Gases for Electrical Insulation to Replace the Most Potent Industrial Greenhouse Gas SF6

Abstract: Gases for electrical insulation are essential for the operation of electric power equipment. This Review gives a brief history of gaseous insulation that involved the emergence of the most potent industrial greenhouse gas known today, namely sulfur hexafluoride. SF6 paved the way to space-saving equipment for the transmission and distribution of electrical energy. Its ever-rising usage in the electrical grid also played a decisive role in the continuous increase of atmospheric SF6 abundance over the last decades. This Review broadly covers the environmental concerns related to SF6 emissions and assesses the latest generation of eco-friendly replacement gases. They offer great potential for reducing greenhouse gas emissions from electrical equipment but at the same time involve technical trade-offs. The rumors of one or the other being superior seem premature, in particular because of the lack of dielectric, environmental, and chemical information for these relatively novel compounds and their dissociation...

Cascade Cockcroft–Walton Voltage Multiplier Applied to Transformerless High Step-Up DC–DC Converter

Abstract: This paper proposes a high step-up dc-dc converter based on the Cockcroft-Walton (CW) voltage multiplier without a step-up transformer. Providing continuous input current with low ripple, high voltage ratio, and low voltage stress on the switches, diodes, and capacitors, the proposed converter is quite suitable for applying to low-input-level dc generation systems. Moreover, based on the n-stage CW voltage multiplier, the proposed converter can provide a suitable dc source for an n + 1-level multilevel inverter. In this paper, the proposed control strategy employs two independent frequencies, one of which operates at high frequency to minimize the size of the inductor while the other one operates at relatively low frequency according to the desired output voltage ripple. A 200-W laboratory prototype is built for test, and both simulation and experimental results demonstrate the validity of the proposed converter.