Research The Impact Of The Load Models On Angle Stability Of Power System

In the wake of development in long-distance and large capacity transmission, large-scale interconnected power grid shows different stability characteristics with regional power grid. It has great significance to analyze the effect of load model on inter-regional angle stability in interconnected power system. Aiming at this problem, some theoretical analysis and simulation has be done in this paper.Firstly, this paper studies the load model and its dynamic characteristics, finds that compared to the static load, the power absorbed by the induction motor has a fast recovery characteristics after a fault. This feature may have a serious impact on the transient stability of the system. Then, the article describes the linear model of the power system including dynamic loads in detail, conducts the small signal stability analysis on this model, identifies the meaning of eigenvalues, eigenvectors and participation factors in the power system, and gets the conclusions that the motor load ratio will affect the small signal stability.Finally, the article analyzes three four-machine two-area multi-machine power systems whose contact situations are different based on BPA. Simulation results show that influence of the dynamic load ratio on interconnected system transient stability related not only to the location of the dynamic load, but also to the contact situations between the two sub-systems. There is no definite regularity about the influence of the dynamic load ratio on interconnected system small signal stabilit.