New approach for planning high-voltage transmission networks

The capital investment required for transmission, subtransmission and distribution networks amounts to roughly over 50% of the total investment for the whole power system. Hence, the problem of planning these networks has received increased attention. The present paper proposes a new and simple planning approach. The process is initialised by considering all possible routes with the maximum allowable number of parallel circuits for each route. As loads and generation schedules are predetermined, system model equations are solved using matrix inversion to obtain line flows. A criterion is established to determine the least effective circuit or route to be chosen for removal in the next step. The line flow and removal procedure is repeated to achieve a planned network which will serve the load, without overloading the lines. Finally, an iterative procedure has been developed to realise the reliability level constraint.