Novel Optimistic approach for design of a UHV AC Transmission Line in India from View Point of Maximum Permissible Exposure Values of Fields

Along the transmission corridor, overhead transmission lines require a portion of land which is to be reserved as right-of-ways (ROW). Main criteria to obtain suitable value of ROW is effects produced by static electric field, magnetic fields and effects due to corona phenomena. A tough need therefore exists to determine the distribution of these fields, especially electric fields throughout the corridor along the length of transmission lines. Determination of the maximum value of the electric and magnetic fields produced by transmission lines close to ground surface has thus become significant. The present research work deals with estimation of electric and magnetic field distribution along with corona effects all the way through the length of an ultra-high voltage transmission line corridor. Analysis is carried out by making use of newly developed computer software that uses MATLAB as programming platform. Charge simulation method (CSM) has been used for computation whereas Maxwell's potential coefficient theory forms the fundamental base of computations. Results for 1200 kV Ultra High Voltage AC line are presented here. Single circuit horizontal line configuration has been considered for analysis. Profiles of all the fields are plotted in 3D environment to find maximum possible value of the fields considering effects of sag through catenary model. Optimization is carried out through a recently developed objective function with the help of Genetic Algorithm. Novel fitness function developed here suggests design modifications in transmission line tower geometries to achieve cost benefits. All the field magnitudes are satisfactorily within permissible limits as suggested in National and International standards.