Steady-state security region (SSR) and its visualization of bulk high voltage power system

This paper studies the steady-state security region (SSR) defined in the injection space and the visualization of its boundary for real bulk power systems based on decoupled power flow equations. The reactive power full SSR is derived from DC flow. The paper describes a model that is convenient to construct active power response SSR using an expanding algorithm. Three conceptions of critical branch, critical bus and active power response SSR are defined, for a specific network configuration and a given injection growth pattern, as well as two algorithms are developed. One of the algorithms is used to identify the critical branch and critical bus in a short period; the other is for computing the response SSR of the critical buses. Based on the algorithms, an approach is presented to display the steady state response security region of a real world power system in real time.