Relations of the Thunder-Stroke Selectivity and Earth Resistivity

The characteristics of thunder-rain cloud have been introduced after learning the lightning. Two factors of cloud-terra discharge have been analyzed. According to the model which is model of the cloud-terra capacitor simulating as parallel plate capacitor, based on the thunder electric current double index model and the Heidler model that was recommended by the International Electrician Commission in IEC1312-1 in 1995, the quantitative relations of the earth resistivity and first cloud-terra discharge lightning current amplitude value was reduced. There is a conclusion which the earth resistivity and first cloud-terra discharge lightning current amplitude value magnitude become the decreasing function relations. And the thunder-stroke selectivity has been investigated. It has provided the important reference to construct each kind of building and defense the lightning.