A fast and reliable decoupled load flow method in rectangular coordinates

Abstract

The authors present a novel version of the fast decoupled load flow method in rectangular coordinates. The decoupling procedure uses a flat start and is based on the second-order load flow method, which is decoupled by suitable manipulations. There are no simplifications in the derivation of the method and the resulting set of equations has the same accuracy as the original expressions. To evaluate the performance and reliability of this method, a comparison with the Newton-Raphson fast decoupled load flow and second-order load flow methods is presented and discussed. Numerical results are obtained on a Micro VAX computer. Simulations are performed on the IEEE-118 bus system and IEEE-24 bus reliability test system. The tests consider several ill-conditioned cases with high R/X ratio and different load conditions. The method exhibits good convergence behavior. In most of the cases its running time is comparable to that of the standard fast decoupled load flow. >