Synchronisation effects and chaos in the van der Pol-Mathieu oscillator

Analysis of a nonlinear oscillator system with one degree of freedom, which includes the van der Pol self-excitation term and parametric excitation of the Mathieu type is carried out in this paper. Interactions between the parametric and self-excited vibrations for regular and chaotic motion are investigated. Synchronisation areas near the main parametric resonance and transition conditions from regular to chaotic motion are determined in this paper. It is also presented that a small external force causes qualitative and quantitative changes in the main parametric resonance and that the external harmonic force transits the system from chaos to regular motion.