Contribution to the Modeling of Electromagnetic Lightning Transients in High Voltage Power Transmission Lines Connecting Regions With High Storm Density

The power grid connects electricity production to end uses, providing a physical link for the circulation of energy flows while providing services to the community. The rapid development of technology makes power grids increasingly complex, transmission lines play a crucial role in electricity transmission. However, transient phenomena such as short circuits caused by lightning can propagate between substations, affecting power distribution and requiring real-time management of electrical quantities to maintain the frequency and efficiency of these systems. This paper deals with the modeling of electromagnetic transients due to lightning in high-voltage lines, especially in thunderstorm areas. The bi-exponential model allows us to faithfully represent the lightning shock wave and its impact on these lines. The modeling of the lightning electromagnetic field and its coupling with a high-voltage line were carried out using Maxwell's equations and a transmission line model. The FDTD method allowed us to present the results of the voltages and currents induced by this field in the time domain. We used the Laplace transform to obtain frequency results. The study applied to the test network in the Democratic Republic of Congo shows that the voltages induced by lightning, linked to the amplitude of the disturbing current, jeopardize the life and safety of HV equipment. The 2D simulations highlight the importance of the coordination of the insulation to guarantee the stability of the power transmission lines. Integrating a passive ohmic-capacitive damping circuit in the control part of the protection system dedicated to tropical areas could attenuate the electromagnetic lightning transients and improve the performance of the high-voltage line.