Saddle-node Bifurcation of Power Systems Analysis in the Simplest Normal Form

That using of the simplest normal form theory, derives the second-order simplest normal form of the power system original differential equation model at the saddle-node bifurcation point, by transforming the higher order solves the problem of resonance coefficient singular, Analysis the system instable phenomenon that is caused by saddle-node bifurcation in use of approximate analytical solution of the power system, In participation factors analysis the impact of the resonance modal to others, reveals the physical mechanism of power system instability caused by saddle-node bifurcation, the saddle-node bifurcation in the voltage collapse at the same time, due to the resonance modal influence, the angle also. There are some values for profound understand the mechanism that system instability be lead by saddle-node bifurcation. Using a power system model verify the above conclusions.