Controlling the chaotic n-scroll Chua's circuit with two low pass filters

Controlling chaos in the chaotic n-scroll Chua's circuit is studied. The proposed control method is based on two low pass filters. First, the unstable fixed points in the n-scroll Chua's circuit are classified into two types according to the characteristics of the eigenvalues of Jacobian at the fixed points. Then the controllability of these two-types of fixed points is studied. Theoretical analysis shows that the first type of fixed points can be stabilized with two stable low pass filters, and the second type of fixed points can be stabilized with a stable low pass filter and an unstable low pass filter. With an appropriately chosen feedback gain k, Hopf bifurcation can be generated and corresponding period orbits can be obtained. Numerical simulations show that the proposed control method is robust to the variations of the system parameters.