ENHANCEMENT OF DYNAMIC STABILITY BY COORDINATED CONTROL OF STATIC VAR COMPENSATORS

An analytical tool to assess the influence of large-scale static VAR compensation on system dynamic stability is presented. A linear state model of an electric power system is developed which considers the representation of synchronous machines and controllable static VAR compensation as subsystems of the state model which interact through the network parameters. Interaction characteristics between subsystems are utilized to help in the comprehension of the role of static compensation on system damping. Based on this concept, compensation hierarchies are defined as some static compensators can influence system-wide damping while others effectively behave as local voltage regulators. This approach also allows better utilization of control capabilities. The coordinates setting of system controllers is explored by a dominant eigenvalue optimization technique to supplement information on phase compensation methods.