Interactive computer program for planning the expansion of meshed transmission networks

Abstract A scheme is described for the interactive development of expansion strategies for transmission networks in which stability and voltage considerations are not of prime importance. According to the planning methodology adopted, the transmission/generation system is to be reinforced when it can no longer feed the peak demand without equipment overload in a single contigency. Outages of generators are considered, as well as the outages of transmission lines and transformers. Generation can be redispatched in order to eliminate overloads. If this is not possible, the model minimizes the load curtailment and identifies the weak parts of the system. It also ranks the possible investments according to their effectiveness in reducing the load curtailment. The planning engineer can build, interactively, several expansion policies by successive investment decisions. The model computes the discounted costs of the various policies developed. The files containing the expansion policies created are also automatically managed by the interactive package. The scheme has been implemented in a package called Tranex which consists of two separate interactive computer programs. An example illustrating the application of the method via this package to the Yugoslav network is given, along with computer performance details and an overview of the program structure.