Evaluation of Lightning Overvoltages for Overhead Transmission Lines Using Unscented Transform

The Monte Carlo method (MCM) is the most widely used statistical approach to evaluate the lightning performance (LP) of overhead transmission lines (OTLs). However, the MCM has a very high computational burden, making LP studies time consuming. To overcome this difficulty, this letter proposes a new alternative approach for calculating the the lightning overvoltages (LOs) using the unscented transform method (UTM). This letter compares the UTM and MCM for calculating LO in insulator strings of OTLs through extensive tests carried out using the Alternative Transients Program (ATP). Such LO evaluation is an essential requirement for LP evaluation of a transmission line. The results indicate that the UTM significantly reduces the processing time to generate LOs while its accuracy is similar to that of the MCM.