By Dr. Hazlee Azil Illias (University of Malaya)
The IEEE Dielectrics and Electrical Insulation Society (DEIS) Malaysia Chapter, University of Malaya High Voltage Research Group (UMHVRG), Transformer Working Group and Malaysian High Voltage Network (MyHVnet) have jointly organised a seminar entitled “Transformer bushing – Design, Testing and Maintenance” on 25th August 2015 in the Faculty of Engineering, University of Malaya, Malaysia. The seminar was presented by Ir. Sanuri Bin Ishak, a Principal Researcher and Head of Section of High Voltage Diagnostic (Transformer & Switchgear), Distribution Unit in Tenaga Nasional Berhad (TNB) Research Sdn. Bhd, Malaysia. The seminar was attended by academic staffs and students from various learning institutions and engineers from various industries in Malaysia, who are working actively in high voltage engineering field.
The seminar combined the theory and speaker’s experience in dealing with bushings during his work as a maintenance engineer in TNB. The seminar covered the following aspects; types of bushings, transformer bushing failure modes and causes, bushing testing & diagnostics, bushing physical condition maintenance, bushing selection criteria, bushing storage and handling guide and risk mitigation to improve transformer bushing performance.
After the seminar, participants were brought to the UM High Voltage Laboratory (UMHVL) for a short lab tour. Then, a Transformer Working Group meeting was held and attended by Transformer WG members.
The abstract of the seminar is as follows:
Bushing is one of the components in the transformer. It is used as an insulated current pathway in connecting terminals of a transformer. The purpose of the bushing is to keep the conductor insulated from the surface it is passing through. The inside of the bushing may contain paper insulation and the bushing is often filled with oil to provide additional insulation. Common bushings failure mode fail due to partial discharge degradation in the insulation. Periodic and condition base maintenance are performed to monitor the bushing insulation. Typically, power factor value of a bushing in good condition will remain relatively stable throughout the service life. The seminar combined the theory and speaker’s experience in dealing with bushings during his work as a maintenance engineer in TNB.