ISSN 0869-6632 (Print)
ISSN 2542-1905 (Online)

Van der Pol oscillator

Self-oscillating systems with controlled phase of external force

The purpose of this work is to study self-oscillatory systems under adaptive external action. This refers to the situation when the phase of the external action additionally depends on the dynamical variable of the oscillator. In a review plan, the results are presented for the case of a linear damped oscillator. Two cases of self-oscillatory systems are studied: the van der Pol oscillator and an autonomous quasi-periodic generator with three-dimensional phase space.

Wave processes in a ring of memristively coupled self-excited oscillators

The purpose of this work is to reveal intrinsic peculiarities of the dynamics and spatial structure formation in an ensemble of the coupled van der Pol self-oscillators in a case of memristive coupling. Two models of memristive coupling are considered: an idealised memristive model and a real one exhibiting the effect of «forgetting» of an initial state after a long time. Methods. Numerical simulation of the equations describing the system under study by means of the fourthorder Runge–Kutta method is carried out.

Synchronization in coupled self­sustained oscillators with non­-identical parameters

The particular properties of dynamics are discussed for dissipatively coupled van der Pol oscillators, non-identical in values of parameters controlling the Andronov–Hopf bifurcation and nonlinear dissipation. Possibility of a special synchronization regime in an infinitively long band between oscillator death and quasiperiodic areas is shown for such system. Non-identity of parameters of nonlinear dissipation results in specific form of the boundary of the main synchronization tongue, which looks like the mirror letter S.

Chaos in the phase dynamics of q­switched van der pol oscillator with additional delayed feedback loop

We present chaos generator based on a van der Pol oscillator with two additional delayed feedback loops. Oscillator alternately enters active and silence stages due to periodic variation of the parameter responsible for the Andronov–Hopf bifurcation. Excitation of the oscillations on each new activity stage is forced by signal resulting from mixing of the first and the second harmonics of signals from previous activity stages, transported through the feedback loops.

Hyperchaos in a system with delayed feedback loop based on Q-switched van der Pol oscillator

We present a way to realize hyperchaotic behavior for a system based on Q-switched van der Pol oscillator with non-linear signal transformation in the delayed feedback loop. The results of numerical studies are discussed: time dependences of variables, attractor portraits, Lyapunov exponents, and power spectrum. 

The impact of electrical couplings on the dynamics of the ensemble of inhibitory coupled neuron-like elements

Topic. The phenomenological model of ensemble of three neurons coupled by chemical (synaptic) and electrical couplings is studied. Single neuron is modeled by van der Pol oscillator. Aim of work is to study of influence of coupling strength and frequency detuning between elements in the case of regime of sequential activity that is observed in ensemble of neuronlike elements with chemical inhibitory couplings. Method. The research is made with usage of analytical methods of nonlinear dynamics and computer modeling. Results.