Fast decoupled state estimation based on current equations

A fast decoupled state estimator (FDSE) based on current equations for the Energy Management System has been presented in this paper. The state estimator algorithm has been developed considering nodal power injections and line power flows as the primary available measurements. This technique avoids gain matrix inversion at each step as the gain matrix developed in this technique remains constant throughout the computation process. The estimation of real and imaginary parts of voltage can be handled separately when the decoupling technique is used which further reduces the resource requirements for this method. The technique presented in this paper has been tested on standard IEEE 14-bus and 118-bus systems and its results are compared with the power equations based FDSE. Results indicate that the current equations based FDSE converges faster than the power equations based FDSE.