Performance Evaluation of High Temperature High Current Conductors

A rapid increase in electric power consumption is witnessed, there is a demand for the uninterrupted power supply. Newer generation units are being built with the increased installed power. The available transmission lines are reaching critical limits of ampacity and sag; hence there exists an intricacy in finding corridors particularly in densely populated cities to construct new overhead lines in many industrialized countries including India. Most of the times, it becomes impossible to obtain a right of way for the new transmission lines; hence, present circumstances demand the use of available lines representing a cheaper solution than going in for an underground transmission. Increasing the transmission capacity of overhead lines using high temperature low sag (HTLS) conductors, replacing original ACSR conductors with approximately the same diameter is one of the techniques. HTLS conductors are capable of withstanding high-temperature, continuous operation above 200 degrees C without loss of tensile strength or increase in sag. In the present work, a computer program is developed in accordance with IEEE Std.738 to estimate the current and temperature distribution for various HTLS conductors and a graphical user interface has been developed to optimize the selection of various hardware accessories used for HTLS conductors. A novel experimental facility has been built for the present study. Results obtained for both simulation and experimental investigations are analyzed and presented. An attempt has also been made to study the effect of magnetic fields due to higher currents in the conductors.