Inherent Chaotic Behavior in Vector Control Drives of Induction Machines

Abstract

In the present article, the existence of chaotic behavior in vector control drives of induction machines is investigated, and a method for avoiding this phenomenon is proposed. It is shown that, contrary to previous research, not only do errors in the estimation of rotor and stator resistances and pulse-width modulation switching techniques cause chaotic behavior in the drives, but these drives may show this phenomenon inherently even with exact parameters. Also, a modified second-order map is introduced to analyze and achieve necessary conditions for the occurrence of bifurcation and chaotic responses. Using this map, the bounds of different parameters to avoid chaotic response can be determined. In addition, a method to compute the largest Lyapunov exponent is explained and implemented to the system for proving the existence of chaotic response. Finally, an experimental setup is prepared to verify analytical and numerical results.

Keywords:

• bifurcation
• chaos
• Lyapunov's exponents
• modified Poincare's map
• vector control drives