Robust optimal control of chaos in permanent magnet synchronous motor with unknown parameters

This paper focuses on the problem of chaos suppression in permanent magnet synchronous motors (PMSM) with uncertain parameters. Firstly, the chaotic characterizations are analyzed, including bifurcation diagram, chaotic attractor, Lyapunov exponents, and power spectrum. Then, by using robust optimal control approach, a simple linear feedback controller is designed to make the system states stable. And the control gains can be obtained from a linear matrix inequality (LMI), which can be resolved easily via the MATLAB LMI toolbox. Based on Lyapunov stability theory, the stability of the proposed scheme is verified. Finally, numerical simulation results are given to demonstrate the effectiveness of the presented method. © JES 2015.