Show simple item record

dc.contributor.supervisor Rajapakse, Athula (Electrical and Computer Engineering) en_US
dc.contributor.author Nanayakkara, Obada Mudalige Kasun Kavinda
dc.date.accessioned 2014-04-11T21:56:01Z
dc.date.available 2014-04-11T21:56:01Z
dc.date.issued 2014-04-11
dc.identifier.uri http://hdl.handle.net/1993/23451
dc.description.abstract The current technology used for location of permanent faults in high voltage direct current (HVDC) transmission lines and cables is based on the travelling-wave principle. This technology has served well for the conventional point-to-point HVDC systems, but is inadequate to handle emerging HVDC transmission configurations such as schemes with very long overhead lines or cables, schemes with a combination of cable and overhead line segments, and multi-terminal HVDC (MTHVDC) schemes. This research investigated accurate and economical ways to locate the faults on dc transmission lines in the aforementioned emerging HVDC transmission configurations. The accuracy of travelling-wave based fault location methods is highly dependent on the accuracy of measuring the time of arrival of the fault generated travelling waves. Investigations showed that post-processing of detection signals such as the line terminal voltages or surge capacitor currents with continuous wavelet transform yields consistent and accurate fault location results. This method was applied for fault location in HVDC systems with extra-long overhead lines and cables using only the terminal measurements. Simulation results verified the effectiveness of this method in locating the faults in a 2400 km long overhead line and a 300 km long underground cable. A new algorithm was proposed to locate the faults in a two-terminal HVDC system consisting of multiple segments of overhead lines and cables, using only the terminal measurements. Application of the proposed algorithm was analysed through detailed simulations. Correct performance was verified under various scenarios. A new algorithm was developed for locating the faults in a star-connected MTHVDC network. This algorithm is also required only the terminal measurements. Its effectiveness was verified through detailed simulations. Finally, a novel measurement scheme for detection of travelling-wave arrival times was proposed. A prototype of this measurement scheme which uses a Rogowski coil to measure the transient currents through the surge capacitors at the line terminals was implemented. Its effectiveness was validated through field tests in a real HVDC transmission system. The proposed measurement scheme could capture significantly clean signals in an actual substation environment, confirming the practicability of implementing the proposed new algorithms. en_US
dc.rights info:eu-repo/semantics/openAccess
dc.subject HVDC en_US
dc.subject DC line fault location en_US
dc.subject fault location en_US
dc.subject haar wavelet en_US
dc.title Line fault location in emerging HVDC transmission systems en_US
dc.type info:eu-repo/semantics/doctoralThesis
dc.type doctoral thesis en_US
dc.degree.discipline Electrical and Computer Engineering en_US
dc.contributor.examiningcommittee Gole, Aniruddha (Electrical and Computer Engineering) Leung, Carson (Computer Science), McLaren, Peter Grant (Centre for Advanced Power Systems, Florida State University, U.S.A.) en_US
dc.degree.level Doctor of Philosophy (Ph.D.) en_US
dc.description.note May 2014 en_US


Files in this item

This item appears in the following Collection(s)

Show simple item record

View Statistics