Untersuchungen zur Beeinflussung des durch Störlichtbögen verursachten Überdrucks in elektrischen Anlagen

Fault arcs in electrical installations occur extremely seldom. However, they can not be avoided totally. Insulation failure, flashover, malfunction or maloperation by service personnel can lead to powerful fault arcs. As a result switchgear installations and even substation buildings may be endangered by thermal and mechanical stress. Metal enclosed switchgears can withstand some hundred mbar overpressure, substation buildings e. g. constructed of bricks may be damaged by overpressures exceeding 3 mbar. The goal of this work is the investigation of possibilities to reduce overpressure due to internal arcs especially in switchgear rooms or substation buildings. The following measures are analysed:- pressure relief openings,- intermediate volumes and relief ducts,- fault arc energy absorbers.Encapsulated (gas insulated) switchgears are provided with overpressure relief devices which lead to the switchgear room.After fault arc ignition pressure rises in the compartment where the arc burns (arc room), the relief devices open and the overpressure in the switchgear room rises. The level of overpressure depends significantly on fault arc duration and power, which can be about some 10 MW in distribution systems. The overpressure reduction in the switchgear room can be achieved e. g. by sufficiently dimensioned pressure relief openings. Another possibility is the use of intermediate rooms as buffer volumes or pressure relief ducts, which can be installed on switchgears draining hot gases. Fault arc energy absorbers are cooling grids, which withdraw energy from hot gases generated by the fault arc with the result of overpressure reduction. The overpressure development is analysed by using two available program packages. The first one leads to pressure results, which are averaged values in the volume under consideration. The second one is a commercial Computational Fluid Dynamics (CFD) tool with three dimensional results. To quantify the effect of fault arc energy absorbers, experiments with a high-current test set-up are performed. The results of these investigations shall contribute to a safe design of measures for overpressure reduction in the case of fault arcs in electrical installations.

Grantor dc:publisher

Publikationsserver der RWTH Aachen University

Year dc:date

2006

Author dc:creator

• Schmale, Michael

Contributors dc:contributor

• Pietsch, Gerhard J.

• info:eu-repo/classification/ddc/620
• Störlichtbogen
• Druckbeanspruchung
• Elektrische Anlage
• Gekapselte elektrische Anlage
• Berechnung
• Ingenieurwissenschaften
• Lichtbogenenergieabsorber
• Störlichtbogenenergieabsorber
• Fault Arc
• Arc Energy Absorber
• Overpressure
• Electrical Installation
• Switchgear

Statement dc:rights

• info:eu-repo/semantics/openAccess

Language dc:language

ger

Identifier

https://publications.rwth-aachen.de/search?p=id:%22RWTH-CONV-123847%22

OAI identifier oai:identifier

oai:publications.rwth-aachen.de:62270