Study of Self-Excitation Over-Voltage and Switching Over-Voltage and Their Suppression Measure in Ultra-High Long Distance Transmission Lines

Based on the discuss and the analyse of the domestic and international study of self excitation over voltage and switching over voltage in 1000kV ultra high voltage long distance transmission line, the main point of the study of these problems is proposed . The first point is the precise production condition of the self excitation over voltage. Besides, the possibility of simultaneity and superposition of the self excitation over voltage aroused by the load rejection in the ultra high voltage long distance transmission line is first proposed in this paper and will result a serious over voltage which will damage the transmission lines transmission equipments and large units. This paper has also indicated that the flexible setting and control technology of the arrestor have a very good prospect .It is proposed to combine the primary and secondary side together to realize the general suppression measure. The main point of the study proposed in this paper is the basic theory of the safe operation of the ultra high voltage grid and the large unit in the future and it has a large economical benefits.