| Optimal power flow (OPF) is one of the major issues in the operation of power systems. This problem can be divided into two subproblems, MVar dispatch or optimal reactive power flow (ORPF) and MW dispatch. The Optimal Reactive Power Flow problem is considered in this thesis. An efficient method for minimization of energy loss over time is presented. The existing ORPF formulations minimize the power loss based on one loading condition. In the proposed method, several loading conditions including the on-line and predicted loading profiles are used in the energy loss minimization process.;A new solution method which treats the transformer taps and capacitor/reactor banks as discrete variables is also addressed. The ORPF problem in most applications is formulated as a nonlinear programming (NLP) problem. However, this problem inherently is a Mixed-Integer Nonlinear Programming (MINLP) problem. A new MIINLP formulation of ORPF with the solution method is proposed and implemented.;Finally, the potential benefits of the application of ORPF for the New Brunswick (NB) Power network is addressed. Two main issues are studied: (1) the effect on power loss, and (2) the changes in voltage profile. The study results specify substantial dollar savings due to power loss reduction, and improvement in voltage profile of the NB Power network. The results are also justified by real-time implementation of ORPF. |
