A technique for the remote inspection and monitoring of partial discharge (PD) activity using an optical network is described. The network uses a LiNbO3, modulator to modulate the intensity of the transmitted laser light approximately proportional to the voltage applied across the modulator. The laser light is transmitted along an optical fibre and measured remotely by a high-speed optical receiver. A capacitive coupler has been used to detect partial discharge activity and act as the modulator's input voltage source. The electro-optic modulator is passive and does not require a power supply at the site of the PD detection sensor. The system has the additional advantages of being immune to electromagnetic interference, having very little signal transmission attenuation, with good sensitivity, compact size, as well as being convenient to use and safe. Both simulation experiments and practical PD tests on two cable systems have indicated that the optical system provides a feasible remote PD monitoring technique for high voltage cable systems.
P. L. Lewin et al., "Partial Discharge On-line Monitoring for HV Cable Systems using Electrooptic Modulators," IEEE Transactions on Dielectrics and Electrical Insulation, Institute of Electrical and Electronics Engineers (IEEE), Jan 2004.
The definitive version is available at http://dx.doi.org/10.1109/TDEI.2004.1349792
Electrical and Computer Engineering
National Grid Transco
Keywords and Phrases
LiNbO3 Electro-Optic Modulator; Capacitive Coupler; High Voltage Cable; On-Line Monitoring; Partial Discharge
Article - Journal
© 2004 Institute of Electrical and Electronics Engineers (IEEE), All rights reserved.