Stabilizing Control in Emergencies Part 1. Equilibrium Point and State Determination

A precondition for stabilizing control during emergencies is the knowledge of the system state (normally requires state estimation) and the system stable equilibrium point (normally requires a load flow computation). These cannot be obtained fast enough in the conventional state space and may be un-obtainable when the system structure is unknown as it can be during emergencies. This paper introduces a valid transformed state space in which the components of the state can always be obtained at each bus from small scale local computations based on local measurements at the bus itself. The stable equilibrium point is always the origin of this state space-thus, a definite target for the stabilizing control is always available. Definitions and working equations are presented and these results are utilized for devising a stabilizing control in a companion paper [1].