Dynamic Characteristics Analysis Of DFIG On Small Disturbance At Electromechanical Time Scale Based On Magnitude/phase Motion Equations And Self-stabilizing/en-stabilizing Properties

Wind power has been developing rapidly in recent years.Large scale wind power provided great benefit for society,as well as historic transform for power system.Power electronics devices have been replacing electromagnetic devices gradually,which has changed the dynamic behavior deeply and brought new challenge for the stable operation of power system.At present,stability analysis of wind power system mainly rely on the detailed mathematical model and mathematical tools such as time domain or frequency domain method,which may cover the physical mechanism of the dynamic behavior.Therefore,this paper is devoted to a universal physical modeling and analyzing method.This paper researched on the dynamic characteristics of DFIG on small disturbance at electromechanical time scale,and proposed a modeling method based on the magnitude/ phase motion equations,and analyzing method based on self-stabilizing/en-stabilizing properties.First of all,based on the basic working principle and multi-scale control frame and dynamic characteristics of DFIG,this paper proposed an analyzing thought on electromechanical scale,established the magnitude/phase motion equations of DFIG,and formed the physical concept of "Equivalent Rotor","Virtual Capacitor","Equivalent Spring".Secondly,this paper combined device model with network model and made a simplification,analyzed the self-stabilizing/en-stabilizing properties between magnitude and phase,obtained the stability motion equation,and established the systemically physical concepts and mathematical expression between state and power.Finally,the simulation verified the accuracy of the magnitude/phase motion equation model,and analyzed the influence of different controller parameters on self-stabilizing and en-stabilizing damping/recovery coefficient.