Optimal voltage level and line bundling for transmission lines

Building new transmission lines is a challenging issue for connecting expected geothermal power plants located in remote areas to the existing electricity network in Australia. Costs associated with transmission line represent a major component of the total cost, which brings up the importance of accurate optimization studies in the design process of the line. This paper introduces an optimisation approach to determine the optimal voltage level and line bundling for transmission lines. It is shown that for long transmission lines carrying large amount of power, ultra high voltage lines with bundled overhead conductors are effective means to minimize total cost. In the proposed problem formulation, costs associated with overhead conductors, shunt and series reactive power compensation and active power losses are considered to obtain an optimal solution.