Title: Insulation Aspects of DC Power Distribution and Photovoltaic Installations

Speakers: Prof. Dr. Peter Zeller and Christoph Diendorfer

Abstract:
DC power distribution systems have numerous benefits compared to AC systems such as no skin effect, no reactive power, and reduced dielectric losses. With the increasing performance of power electronic semiconductors, DC systems can be an economical solution for medium voltage systems and could become an important technology for electrical energy supply.

DC systems come with their own set of challenges. One issue researchers have to investigate is the different fault behavior such as stable glowing contact and arcing effects, and special DC (surface) breakdown effects. All around the world, the scientific community is focusing on novel monitoring solutions for DC insulation systems and the detection and localization of arcs, to provide fundamental technologies and realize early switch-off approaches, which would limit the negative effects of arc fault in electrical equipment.

The seminar will be split into two selected topics out of the whole DC system protection aspects: (1) DC surface breakdown effects and arc and glowing contact detection in DC (PV) systems, and (2) DC surface breakdown experiments at a gap distance of 1 cm with different levels and types pollution and insulator materials. The talk will describe the experimental setup, the instrumentation, and discuss the measurement results.
Initial arcing experiments have been carried out using a 400 V PV system with a special contact system, providing the spectrum of contact current and voltage in order to analyze the different spectra of healthy contacts, glowing contacts, and arcing contacts. The introduced results (high speed filming of the arc) show details of arc behavior originating the measured spectra. A comparison of the spectra indicates an appropriate approach to identify arcs, but not glowing contacts in DC systems.

Biographies:
Dr. Peter Zeller graduated from the Technical University Vienna in Electrical Energy Engineering.With his PhD work he investigated the interaction of the arc plasma with the cold surrounding air in arc chutes. He was the head of the international development department for surge arresters at ABB Switzerland before he joined the University of Applied Sciences Upper Austria. Currently he is the head of the international (and in English taught) study programs bachelor and master of Electrical Energy Engineering. Dr. Peter Zeller researches in the fields of high voltage engineering, electric arcs and DC Grid technology.

Christoph Diendorfer MSc graduated from the university in applied science Upper Austria in Automation Engineering. His Master thesis focused on a fully automated recovery in a Medium Voltage Direct Current shipboard power system in less than 8 ms. Later he started his career as a researcher in the University of Applied Science Upper Austria in the field of high-current engineering.

This event is jointly organized by the IEEE PES Georgia Tech Student Branch, the Energy Club at Georgia Tech, and the Plasma and Dielectrics Lab. Light refreshments will be served.