Since 750 kV transmission lines locate in the high altitude areas of northwest China where the environment condition is comparatively severe, the electromagnetic environmental problems in substations appear to be more prominent. As can be seen from the field observation results of the in-service substation, the frequent or permanent presence of corona discharge is obvious adjacent to the corona rings and end fitting hardware. This can result in distinct consequences of radio interference and audible noise, thus it may necessitate reasonable design of corona rings to improve the E-Field conditions. In this article, using a three-dimensional finite element method model, the E-Field distribution of circuit with value controlled reactors in the 750 kV substations is researched. According to both actual knowledge of phenomena and practical experiences form test facilities and lines in operation, a viable value of E-Field intensity is ascertained to control the electric field, and the configurations of some corona rings are optimized subsequently to diminish the corona discharge. And then an exhaustive suggestion about the design and arrangement of corona rings is proposed. The results could provide experiences and references for the design of 750 kV AC substation, and better technical performance and economic competitiveness is predicted to be implemented.
[1]
Zongren Peng,et al.
Study on the voltage-sharing performance of porcelain insulators on 750kV compact double circuit transmission line
,
2009,
2009 IEEE 9th International Conference on the Properties and Applications of Dielectric Materials.
[2]
L. E. Zaffanella,et al.
Audible-Noise Reduction by Bundle Geometry Optimization
,
1973
.
[3]
Jiansheng Yuan,et al.
A finite element domain decomposition combined with algebraic multigrid method for large-scale electromagnetic field computation
,
2006,
IEEE Transactions on Magnetics.
[4]
Numerical performance of the distributed vector finite-element time-domain algorithm
,
2004,
IEEE Transactions on Magnetics.
[5]
Zhang Shi-ling.
Voltage-sharing Characteristics of Porcelain Insulators for UHV AC Transmission Lines
,
2010
.