In nominal Pi model, it is assumed that the half of the capacitance concentrate at the each end of the line. The medium transmission line is sub-divided into Pi – model and T – model. The effect of the line is more at high frequency, and their leakages inductance and capacitance is considered to be neglected. The capacitance of the medium transmission line is considered to be lumped at one or more point of the lines. The capacitance of the medium transmission line cannot be ignored. The line which is ranging from 80 to 240 km is termed as a medium transmission line. While studying the performance of the short transmission line only resistance and the inductance of the line is calculated. The effect of capacitance on the short transmission line is negligible, but for cable where the distance between the conductor is small, the effect of capacitance cannot be ignored. I have handcrafted this course to allow students to acquire core fundamental knowledge. The capacitance of the line is governed by their length. Transmission Power Engineering Fundamentals is a comprehensive video course where you can learn industry specific knowledge about the Transmission power system that you would not have known unless you worked within the utility industry for a number of years. If the line is not more than 80 KV or if the voltage is not over than 66 KV then the line is known as the short transmission line.

The comparison chart of the transmission line is shown in the figure below. The term performance means the sending end voltage, sending end currents, sending end power factor, power loss in the line, efficiency of the transmission line, regulate and limit of power flow during efficiency and transmission, regulation and limits of power during steady state and transient condition. These parameters along with the load and the transmission line determine the performance of the line. The transmission line has resistance R, inductance L, capacitance C and the shunt or leakage conductance G.

Electrical transmission lines basics