Bifurcation of Limit Cycles of a Perturbed Pendulum Equation

Year:    2024

Author:    Jihua Yang

Journal of Nonlinear Modeling and Analysis, Vol. 6 (2024), Iss. 2 : pp. 371–391

Abstract

This paper investigates the limit cycle bifurcation problem of the pendulum equation on the cylinder of the form $\dot{x} = y, \dot{y} = − {\rm sin} x$ under perturbations of polynomials of ${\rm sin} x,$ ${\rm cos} x$ and $y$ of degree $n$ with a switching line $y = 0.$ We first prove that the corresponding first order Melnikov functions can be expressed as combinations of anti-trigonometric functions and the complete elliptic functions of first and second kind with polynomial coefficients in both the oscillatory and rotary regions for arbitrary $n.$ We also verify the independence of coefficients of these polynomials. Then, the lower bounds for the number of limit cycles are obtained using their asymptotic expansions with $n = 1, 2, 3.$

Journal Article Details

Publisher Name:    Global Science Press

Language:    English

DOI:    https://doi.org/10.12150/jnma.2024.371

Journal of Nonlinear Modeling and Analysis, Vol. 6 (2024), Iss. 2 : pp. 371–391

Published online:    2024-01

AMS Subject Headings:   

Copyright:    COPYRIGHT: © Global Science Press

Pages:    21

Keywords:    Pendulum equation complete elliptic function Melnikov function limit cycle.

Author Details

Jihua Yang