Research on active voltage stability of distribution network based on the bifurcation theory

Voltage control faces severe challenges owing to the access of the large number of distributed generation in the active power distribution network. The start and development process of voltage instability or collapse and related mathematical conditions were eager to know. Active distribution network is a typical nonlinear nonautonomous systems, Bifurcation theory one of the effective way solving the nonlinear dynamic system was adopted to do a study on voltage instability or collapse in the active power distribution network. Here, the influence of the filter reactor of the micro power interface and reactive load on voltage stability were analyzed, which provided help to understand voltage instability and its boundary conditions. Simulation analysis shows that under the given conditions, With the increase of the filter reactance value, the active power distribution network bifurcated; With the increase of reactive load, the public bus voltage reduced, then active power was in a state of voltage instability. The simulation results are consistent with theoretical analysis. Bifurcation theory can be also applyed in influence of other parameters in the active power distribution network upon voltage stability, its physical concept and the details are clear, the conclusion can provide reference for researchers engaged in the power grid stability.