Overvoltages during switching operations of vacuum switching devices

• Main Authors: Vukelja Petar, Naumov Radomir, Mrvić Jovan, Hrvić Dejan
• Format: Article
• Language: English
• Published: Electrical Engineering Institute Nikola Tesla 2013-01-01
• Series: Zbornik Radova: Elektrotehnički Institut "Nikola Tesla"
• Subjects: vacuum circuit breaker; vacuum contactor; overvoltage; network
• Online Access: http://scindeks-clanci.ceon.rs/data/pdf/0350-8528/2013/0350-85281323177V.pdf

This paper presents the results of experimental studies of voltage phenomena in the switching operations of vacuum switching devices made by various manufacturers in several different configurations of 6 kV, 10 kV, 20 kV and 35 kV networks. During switching-on operations of the inductive loads, re-ignition of the electric arc between the contacts of the vacuum switching devices appears. Each arc ignition appearance leads to overvoltages with gradients close to those of lightning overvoltages. Switching-off operations of the inductive loads with vacuum switching devices leads to the cutting of the current before it passed through a natural zero and the appearance of multiple re-ignition of the arc between their contacts. All this leads to significant overvoltages on the equipment insulation. The analysis of surges in the studied networks, and the measures and means to reduce the stress of isolation are proposed.