Electro-Optical Measurement of Electric Fields for Pulsed Power Systems

Pulsed electric fields (PEFs), which are generated by pulsed power technologies, are being tested for their applicability in food processing through protein conformational change and the poration of cell membranes. In this article, enzyme activity change and the permeabilization of agricultural products using pulsed power technologies are reviewed as novel, nonthermal food processes. Compact pulsed power systems have been developed with repetitive operation and moderate output power for application in food processing. Firstly, the compact pulsed power systems for the enzyme activity change and permeabilization are outlined. Exposure to electric fields affects hydrogen bonds in the secondary and tertiary structures of proteins; as a result, the protein conformation is induced to be changed. The conformational change induces an activity change in enzymes such as α-amylase and peroxidase. Secondly, the conformational change in proteins and the induced protein functional change are reviewed. The permeabilization of agricultural products is caused through the poration of cell membranes by applying PEFs produced by pulsed discharges. The permeabilization of cell membranes can be used for the extraction of nutrients and health-promoting agents such as polyphenols and vitamins. The electrical poration can also be used as a pre-treatment for food drying and blanching processes. Finally, the permeabilization of cell membranes and its applications in food processing are reviewed.

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Pulsed Power Systems for Application of Pulsed Electric Fields in the Food Industry

Pulsed Electric Fields Technology for the Food Industry - Food Engineering Series ◽

10.1007/978-0-387-31122-7_8 ◽

2006 ◽

pp. 223-238 ◽

Cited By ~ 2

Author(s):

Hennie Mastwijk

Keyword(s):

Power Systems ◽

Electric Fields ◽

Food Industry ◽

Pulsed Electric Fields ◽

Pulsed Power

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Electro-Optical Measurement of Intense Electric Field on a High Energy Pulsed Power Accelerator

10.21203/rs.3.rs-163634/v1 ◽

2021 ◽

Author(s):

Israel Owens ◽

Chris Grabowski ◽

Andrew Biller ◽

Ben Ulmen ◽

Nathan Joseph ◽

...

Keyword(s):

Electric Field ◽

Electromagnetic Interference ◽

Pulse Width ◽

Optical Measurement ◽

High Energy ◽

Pulsed Power ◽

Operating Parameters ◽

Radiation Output ◽

Scientific Experiments ◽

High Fields

Abstract We describe a direct electro-optical approach to measuring a strong 118 MV/m narrow pulse width (~33 ns) electric field in the magnetically insulated transmission line (MITL) of a pulsed power accelerator. To date, this is the highest direct external electric field measured electro-optically in a pulsed power accelerator, and it is between two to three orders of magnitude higher than values reported in comparable high energy scientific experiments. The MITL electric field is one of the most important operating parameters in an accelerator and is critical to understanding the properties of the radiation output. However, accurately measuring these high fields using conventional pulsed power diagnostics is difficult due to the strength of interfering particles and fields. Our approach uses a free-space laser beam with a dielectric crystal sensor that is highly immune to electromagnetic interference and does not require an external calibration. Here we focus on device theory, operating parameters, laboratory and pulsed power accelerator experiments as well as challenges that were overcome in the measurement environment.

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Metallic Glasses in High-Energy Pulsed-Power Systems

Glass … Current Issues ◽

10.1007/978-94-009-5107-5_14 ◽

1985 ◽

pp. 188-199 ◽

Cited By ~ 2

Author(s):

Carl H. Smith

Keyword(s):

Power Systems ◽

Metallic Glasses ◽

High Energy ◽

Pulsed Power

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Pulsed Power Systems

Encyclopedia of Physical Science and Technology ◽

10.1016/b0-12-227410-5/00621-9 ◽

2003 ◽

pp. 277-285

Author(s):

M. Kristiansen ◽

J. Dickens

Keyword(s):

Power Systems ◽

Pulsed Power

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Influence of DC Electric Fields on Pollution of HVDC Composite Insulator Short Samples with Different Environmental Parameters

Energies ◽

10.3390/en12122304 ◽

2019 ◽

Vol 12 (12) ◽

pp. 2304 ◽

Cited By ~ 5

Author(s):

Xinhan Qiao ◽

Zhijin Zhang ◽

Xingliang Jiang ◽

Tian Liang

Keyword(s):

Power Systems ◽

Electric Fields ◽

Particle Motion ◽

Particle Diameter ◽

Environmental Parameters ◽

Composite Insulator ◽

High Voltage Direct Current ◽

Electrical Stress ◽

Motion Characteristics ◽

Dc Electric Fields

Pollution-induced flashover is a serious threat to the safe operation of power systems. With the development of High Voltage Direct Current (HVDC), it is necessary to study insulator contamination in DC electric fields. In this paper, the energized wind tunnel contamination test was conducted in order to systematically study the pollution ratio, k (ratio of non-soluble deposit density (NSDD) of a DC-energized condition to a non-energized condition), under different environmental parameters. Later, a two-dimensional contamination model of short samples of an HVDC composite insulator was established. The particle motion characteristics under different environmental parameters were then analyzed by the finite element method (FEM). The research results showed that—the DC electric field had an influence on particle motion but in different environments, the degree of influence was different. In addition, k was found to largely vary, with a variation in the environmental parameters. When the electrical stress (Es) increased from 0 to 70 kV/m, k increased gradually. However, when the wind speed (ws) increased, k experienced a decreasing trend. Finally, as the particle diameter (dp) decreased, k increased at first, followed by a decrease, and then again showed an increase. The results of the pollution ratio, k, for different environmental parameters are of great importance for guiding anti-pollution work in power systems.

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