Application of Domain-Separation Technique for Stability Determination of Five- Phase Induction Motor Drive System

Abstract

The effect of variation of system parameters on dynamic stability of the system can be studied using Domain-separation technique. This technique utilizes two parameters at a time to study the stability of the motor drive. Domain-separation technique is very simple, robust and effective when compared to the conventional classical methods such as Routh Hurwitz, root locus etc. This paper deals with the stability analysis of a five phase induction motor drive based on constant V/f ratio. Complete block diagram of the drive in closed loop mode has been developed and the simplified diagram is obtained thereafter. The overall transfer function is also determined and is used to obtain the stability/instability regions of the drive. The most stable regions for different values of voltage and frequency keeping V/f ratio constant is obtained which indicates the region of maximum stability. The mat lab codes have been developed to carry out the stability analysis of the five phase induction motor drive system.