The Analysis of Weakness and Limitations for the Protective Angle Method based on IEC Standard 62305

The protective angle method based on IEC standard 62305 is an important concept that is popularly utilized to design the air termination for the external lightning protection system because this method can be easily implemented based on trigonometric calculation. However, the protective angle method demonstrates the weakness and limitation in a factor of the penetration distance which is rarely mentioned in publications. Especially, the penetration distance of the protective angle method is difficult to evaluate. The penetration distance is always neglected implementation while the penetration distance directly influences the lightning flash into the structure’s building. Thus, the effect of a penetration distance cannot be definitely neglected.As mentioned above, this article presents the simulation results and analysis of the penetration distance for the protective angle method based on IEC standard 62305, as well as, this article illustrates the concerned mathematical correlation and the approximate correlation for implementation respectively.