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• Analysis of the lines shielding failure and back flashover performance. • Investigating the impact of each flashover parameter by multivariate analysis. • Simulated fault waveforms exhibit similar pattern with recorded field waveforms. • The average peak voltage difference between the simulated and actual data is 6 %. • Obtained waveforms are useful for designing lightning fault classification system. Lightning overvoltage causes outages of transmission lines (TLs) in tropical countries. Identifying and analyzing the key factors responsible for tripping the lines can improve the performance of the lines. In this work, the flashover patterns due to direct lightning strikes on 275 kV double circuit TLs and towers in Malaysia was evaluated with Electromagnetic Transient Program (EMTP-RV). Three parameters that include lightning current magnitude, power frequency angle and tower footing resistance were analyzed on the line performance during direct lightning strikes. The simulated results found that two key parameters, lightning current at 270 kA and footing resistance at 50 Ω, reveal the highest impact on the insulator flashover. This finding was also verified from multivariate analysis results which is rarely found in the previous works in this field. As a key contribution in this work and in validation to the model, the simulated fault waveform patterns and voltage magnitudes were compared with the actual site data obtained from six different locations in Peninsular Malaysia. The analyzed results show a similar waveform pattern with an overall average voltage magnitude difference of 6.0 % before and after fault. The model is useful to electric utilities for analyzing transient performance of TLs. [Display omitted] [ABSTRACT FROM AUTHOR]

• Analysis of NGLA, EGLA, and MCIA performance on mitigating double circuit tripping. • Installing four arresters per tower is the most optimal and universal solution. • All arresters are operating below manufacturers' maximum discharge energy level. • MCIA discharges 54% and 44% less energy than NGLA and EGLA respectively. • The most suitable arrester was selected based on the proposed protocol. Direct lightning strikes on overhead lines and towers causes power system outages. Optimal surge arrester placement is a practical and economical protection technique. From research trends, three types of transmission line arresters are in practice: Non-Gapped Line Arrester (NGLA), Externally Gapped Line Arrester (EGLA) and Multi Chamber Insulator Arrester (MCIA). This study proposed a simplified guide for selecting the most suitable line arrester considering the placement configurations, double circuit outage prevention and energy capabilities. Electromagnetic Transient Program was implemented to analyze back flashover performance of a typical 275 kV double circuit transmission line in Malaysia. Critical flashover parameters considered are lightning current magnitude, tower footing resistance, and power frequency angle. Analyzed results from the three arresters found that installing four arresters, two per circuit, at the lower and upper phases respectively, is the most optimal and universal double outage mitigation technique. Energy comparison reveals that MCIA discharges 54% and 44% less energy than NGLA and EGLA respectively. Also, from 132 kV system results, MCIA discharges 74% and 22% lesser energy respectively. From further validation of the simulation model, NGLA discharged 23.8% more energy than EGLA from experimental results. The proposed guide is applicable to double circuit lines below 275 kV. [ABSTRACT FROM AUTHOR]