Stability Analysis of Symmetrical Induction Motor with Parameter Variation

This paper deals with the stability analysis of symmetrical induction motor. The symmetrical induction machine may become unstable over a range of frequencies even though the machine operates from a balanced, sinusoidal, zero impedance source. Small displacement equations valid for small excursions about an operating point are established from the machine equations expressed in synchronously rotating reference frame. Because the resulting equations are linear, any of the conventional techniques may be applied to establish system stability. This paper presents the use of conventional techniques for symmetrical induction machine in synchronously rotating reference frame. The regions of unstability may vary with parameter variation. The machine parameters are affected by variation of temperature and saturation level of the machine. The need for increased accuracy demands a computing model that takes the variation in the parameter during the starting point. This study shows the stability analysis with the parameter variation and effect of parameter variation on stability.