Evaluation and Prediction of Over-Voltages Effects Caused by Direct/Indirect Lightning Stroke on Complex Power Distribution Networks Using High Frequency Modeling of the Components

In this paper by transient behavior modeling of all components in the distribution network, the overvoltages caused by direct and indirect of lightning strokes has been predicted. The influence of different parameters have been studied such as lightning current maximum, grounding system with considering its high frequency models and nonlinear phenomenon of soil ionization, the different load models and soil resistivity. Also the effects of different conditions have been evaluated such as the adjacent buildings in urban distribution lines and its role to remove some of surge arresters, use of shielding wire in some areas with high density of lightning, use of cables at the junction of overhead line transformer to reduce the over-voltages. An appropriate algorithm is proposed by considering the parameters affecting lightning overvoltages to evaluate the effects of these overvoltages on the distribution network. The results of this study can be used in choose of the appropriate insulation level for distribution network equipment, economic evaluation in network design and removal and addition of surge arresters.