Transmission Planning - Load Flows and Beyond

Modern transmission planning is not simply confined to load flow, contingency analysis and stability analysis. With multiple transmission owners whose assets are operated by an ISO/RTO, the traditional function of transmission planning is being subjected to a new dichotomy. Should it take a "top-down" or "bottom-up" approach? while the top-down approach enables the effective use of resources globally, the bottom-up approach makes implementation easier. Consequently, transmission owners are being driven by the "plan global, act local" adage. In this paper, the authors explore the consequences of this paradigm. The paper reviews the traditional transmission planning process and highlights its new needs and implementation models. The paper shows the need for software simulation tools to address these issues and identifies typical requirements for such tools. The paper concludes with a simple three-step approach for its use in integrated transmission planning