Power electronic converters are commonly used in daily life, and the nonlinear phenomena that arise during their operation have garnered significant attention. Several classical nonlinear phenomena are introduced, and their causes are discussed. Then, the Hopf bifurcation phenomenon is analyzed in detail through specific examples. In addition, the causes and cases of coexisting attractor phenomena in power electronic converters are analyzed. Based on these discussions, potential directions for studying nonlinear system dynamics in power electronics are presented.