Normal form analysis of stressed power systems: incorporation of SVC models

In this paper a comprehensive analytical technique based on normal form theory and symbolic computer algebra is proposed for the analysis of non-linear inter-area oscillations in stressed power systems that incorporate the operation of Static VAR Compensators (SVCs). A second-order representation of the power system is derived that considers the explicit representation of synchronous machines and multiple SVCs in the state representation. On the basis of this model, normal form theory is used to study non-linear power system behaviour following large disturbances. The proposed approach is general and may be extended to include other FACTS devices. A simplified 4-machine, 11-bus test system is used to study the effect of SVC voltage support on system damping.