Study of linear models in steady state analysis of power systems

This paper studies quantitatively the relative merits of commonly used linear models in steady state power system analysis. The 'DC model' assumes negligible resistances and flat voltage profiles, and relates the bus phase angles to real power injections. A new linear model which accounts for the voltage and reactive power flows is developed and used in the comparative study. The first iteration of the Jacobian matrix, and the fast decoupled models are other linear models considered in the study. The figure of merit for comparison is taken as the root mean square difference of similar quantities such as bus voltages and line active and reactive flows. A six-bus system from Wood et al. (1996) is used for the testing. Results show significant potential for the new linear model.