Bifurcation and Chaos in indirect field-oriented controlled induction motor drive system

In this paper, the higher-order three-phase indirect field-oriented controlled (IFOC) induction motor is modeled in synchronous reference frame. The IFOC induction motor is analyzed numerically to investigate the system behavior due to control parameters change. The slip speed compensator, integral, and proportional gains variations of the speed loop controller are used to confirm the system dynamics. The simulation results show that the chaos behavior is noted in small region of the slip speed compensator gain which is difficult to be observed through the dominant limit cycles and fixed-point solutions. The effects of the integral and proportional gains change on the system dynamic are verified. Also, the system exhibits period-doubling bifurcation (period-2, period-4, period-8, and period-16) route to chaos. The bifurcation diagram and Lyapunov exponent spectrum assign these situations. The phase portrait and time response results are also presented. The system has multistability and coexistence of different attractors for the same system parameters as represented in the basins of attractions plots.