Dynamic eigenvalue analysis of a self-excited induction generator feeding an induction motor

This paper presents both transient responses and dynamic stability of an isolated self-excited induction generator (SEIG) supplying an induction motor load. The d-q axis small-signal induction-machine models based on stationary and synchronously rotating reference frames are employed to calculate system eigenvalues versus time under different operating conditions. A nonlinear magnetizing curve of the studied SEIG is represented by an arctangent continuous function to replace piecewise linear approximations or a polynomial, and the cross saturation effect in the SEIG can be easily included. From the analyzed results, the proposed method can give a clear investigation on system dynamic behavior from the viewpoint of small-signal stability. The experimental results obtained from laboratory induction machines confirm the validity of the proposed approach.