The simulation experiment of induction lightning overvoltage on the distribution line

1. RCLP St. Petersbury, Russia The simulation experiment of induction lightning overvoltage on the distribution line Huang Ying1,2, Zeng Rong1, Yu Zhanqing1, Lu Guojun3, Liu Yu3, Wang Zezhong1, Liu Yi1,Tang Bo2 1 State Key Laboratory of Power System, Department of Electrical Engineering, Tsinghua University, 2 College of Electrical Engineering & New Energy, China Three Gorges University 3The Electric Power Test Research Institute of Guangzhou Power Supply Bureau 2014-5-27

2. OUTLINE Conclusions Analysis of the experiment results The basic ideas of simulation experiment Introduction Scheme of simulation experiment

3. Introduction Direct lightning stroke Lightning disterbance Main reason in distribution line Induction lightning • Easier to be carried out • And parameters Controllable • But a degree of distortion Simulation experiment Experiment research methods Full-scale experiment • Carried out without distortion • But influenced by environment and cost much

4. The basic ideas of simulation experiment Reduced scale in velocity of electromagnetic wave propagation in space 1 Reduced scale in current amplitude Si Reduced scale in line capacitance and line inductance Sa Reduced scale in line capacitance and line inductance Sa Reduced scale in time Sa Reduced scale in length Sa

5. Scheme of simulation experiment Overall scheme of simulation experiment 10kV high pressure pulse generator

6. Scheme of simulation experiment current probe voltage divider electric-field probe voltage probe b c d a

7. Scheme of simulation experiment • The reduced scale in length Sa is 1/20. • the length of the simulation distribution line is 11 m, and the height of simulation line is 0.5 m. • The distance between the lightning channel and the centre of the simulation line is 1.1m. • The time of current propagation of the simulation lightning channel from bottom to top is about 60 ns

8. Analysis of the experiment results THE THEORY OF CALCULATION MTLE lightning return model Cooray-Rubinstein electromagnetic propagation model Agrawal field-to-transmission line coupling model calculations lightning induction overvoltage The measured voltage is about 3 times the calculated voltage and the voltage waveform decreases rapidly after the peak. Then reach a negative peak. But the calculated voltage decreases gradually and finally towards zero The waveform measured before 60 ns was low distortion as showed

9. Analysis of the experiment results THE RELATIONSHIP BETWEEN U AND h THE RELATIONSHIP BETWEEN U AND d • The higher the height is, the induction overvoltage is.Themeasured result • The measured result agrees with the calculated result approximately, which increase with the height d linearly • The smaller the distance d is, the earlier the voltage waveform start and the higher the peak is. • The measured result agrees with the calculated result approximately, which decrease with the distance d linearly.

10. Conclusions • The scheme of simulation experiment of induction lightning overvoltage is varied from papers. Because the point of this experiment is the lightning outage rates on distribution line, an accurate measurement at the start of the induction overvoltage waveform is a must • The scheme of the experiment, the waveform before 60 ns is agree with the fact, after the time there is a great distortion • Comparing the measured voltage with the calculated voltage, the two result are matched approximately, so it is with amplitude of induction overvoltage and distance d, amplitude of induction overvoltage and height h. Furthermore, induction overvoltage decrease with the distance d linearly and increase with the height d linearly

11. Thank you!