Identification of critical areas for potential wide- area based control in complex power systems based on coherent clusters

This paper describes a novel technique that identifies critical clusters of synchronous generators in multi-machine power systems based on wide-area signal measurements and coherency property between systems´ generators. The technique used in this paper utilises the concept of Centre of Inertia (COI) to represent each identified coherent cluster by its approximate representative angle following a system disturbance. Each cluster´s representative angle is then evaluated with regard to the centre of angle (Inertia) of the entire system. The evaluation, thus, determines the most critical cluster for the encountered disturbance. Therefore, the identified area will be optimal placement for potential wide-area control. For example, transmission lines that connect these critical areas can provide wide-area feedback signals to wide-area based damping controller such that power system oscillations can be dealt with more effectively. The method has been applied to the standard IEEE 16 generator 68 bus system.