Prediction of Electromagnetic Disturbance by Lightning Strike in UHV Substation

Electromagnetic compatibility issue of the protection and control equipment in UHV substation is of great importance to ensure the reliable and stable UHV power grid. Combined the method of moment with the Fourier transform,the transient electromagnetic field at the relay cell zone,current flow in the cable shield and common-mode voltage in the cable core are investigated due to the lightning strike on the lightning rod in UHV substation. The simulation results show that:(1) the maximum transient magnetic field at the relay cell zone is about 2285 A/m and the metal shielding structure on the wall of the relay cell is necessary to satisfy the requirements of pulse magnetic field immunity for the secondary equipment in UHV substation; (2) the current in the cable shield will not lead the secondary cable burned due to the shunt of the multi-cable and auxiliary copper bar; (3) the common-mode voltage on the cable core is below 1kV and satisfies the requirements of surge immunity for the secondary equipment in UHV substation.