Energy management system functions in deregulated power systems

Abstract

The market structures for electric energy and power are changing. In the past interconnected electric utility systems dealt only with each other to buy and sell power and energy. In recent times, the electric power industry is facing the deregulation and restructuring challenges because federal regulations are opening it up to competition. Due to this important change, to maintain a securely operating system will become more difficult. Therefore, the energy management system functions must be improved and adapted to this new deregulated and competitive environment. In this thesis two important functions of the energy management system are studied, the state estimation function and the optimal power flow function. Related to the state estimation function, the robustness of the least absolute value estimator is reviewed, methods to improve its robustness are investigated, and a new procedure based on a matrix stretching method is proposed. The observability problem is also studied and a procedure to solve the measurement placement problem for network observability is developed. Finally methods for solving the optimal power flow problem are reviewed, and an optimal power flow prototype program applied to minimize the generation cost subject to the real power balance and branch power flow limits is developed.