Bifurcation analysis of the influence of generator excitation forms on system voltage stability

Based on a typical power system model, this paper simulates the scenario of the increase of active power output of a proximal generator around certain bus node and applies bifurcation theory to study the influence of different excitation forms on system voltage stability after reaching generator excitation saturation. With numerical bifurcation analysis software MATCONT, the simulation analysis results show that the smaller the excitation output upper limit value is, the earlier the bus voltage reaches the Hopf bifurcation with the increase of active power output. In the case of self-shunt excitation, the output of the excitation upper limit value is constrained by the generator terminal voltage. Therefore, the bifurcation point in this case occurs earlier than that in the case of separate excitation.