Reactive Power Optimization Of Power Systems With Voltage Stability Constrains

During the connection of the big grids and the application of open-access market principles, the security and stability of the power systems become a big challenge. It is more and more important to find the balance of the security and the economy of the power system.Reactive Power Optimization is an effective measure to find the equal point of the operating power system both considering the security and the economy. The objective of the general Reactive Power Optimization is only to reduce the loss of the power system on condition that the voltage is in a high level. But the research shows that the voltage can be in a high level in the limited point of the steady-state voltage stability. So this thesis presents the Voltage Stability Constrained Reactive Power Optimization formulations. New formulations are on the basis of the theory of the bifurcation and the Jacobi matrix eigenvalue structure analysis incorporating the margin and state index of the voltage stability. The algorithm of the optimization is Predictor-Corrector Primal-Dual Interior Point Method.The optimal model presented in this thesis is tested on a 57-bus system standard network, the calculation results indicate that the constructed model can reduce the loss of the power system under an enough voltage stability margin effectively.