Abstract of Thesis presented at COPPE/UFRJ as a partial fulfillment of the requirements for the degree of Master of Science (M.Sc.)

State Estimation by Interior Point Method With Adjustment of Inequality Constraints

Carlos Alberto Nunes dos Santos Filho

February/2006

Advisor:

Alexandre Pinto Alves da Silva

Department:

Eletrical Engineering

      This dissertation aims at adding inequality constraints of transformer tap position to state estimation in power systems. Inside of a real time supervisory and control environment, the state estimation is the core of security analysis functions because it provides the system's states to the others network analysis tools.
      Two developments are present in this work with the aim of strengthening the estimation process. In the first, the addition of inequality constraints is solved by an interior point method based on logarithmic barrier. In the second, a method of treatment of parameter errors based on residual sensitivity analysis is presented. The propose is to adjust the limits of inequality constraints in each step of state estimation process infering accurancy to the estimate parameter.
      The results obtained with two equivalents of Brazilian network system show the efficiency of the proposed methods.