Circuits and Systems
Technical Dialogue Session
Modeling and Simulation of Converters and Systems
Boost converter, mathematical model, nonlinear saturation, DIDF
Linear small-signal average model of the dc-dc converters is often used to evaluate the converter stability, where the converter instability is customarily featured by divergence. However, in fact, the linear model can hardly holistically characterize the response of the converter due to nonlinearity. Taking the nonlinear components such as saturation into account, this paper establishes an accurate mathematical model of the Boost converter, where the nonlinear saturation is modeled by dual-input describing function (DIDF). This model could successfully predict the limit cycle phenomenon rather than divergence when system is unstable. Simulation results confirm the theoretical expectation.