Bifurcation analysis for power system voltage stability based on singular perturbation method

The dynamic of a large-scale power system can be represented by parameter dependent differential-algebraic equations (DAE) in the form of ^{x= f(x-y-P)} and ^{()= s[x,y,P)} . When the parameter p of the system (such as load of the system) changes, the stable equilibrium points may lose their dynamic stability at local bifurcation points .Then the system will lose its stability at the feasibility boundary, which is caused by one of three different local bifurcations: the singularity induced bifurcation, saddle-node and Hopf bifurcation. In this paper, the dynamic voltage stability of power system will be introduced and analyzed. Perturb and Taylor´s expansion (PTE) technique is used to describe the DAE by singularly perturbed ordinary differential equations (ODE), and equilibrium manifold is solved by continuation method. The analysis avoids the singularity induced infinity problem, which may happen at reduced Jacobian matrix analysis, and is more computationally attractive.