Pulse train controlled quadratic buck converter operating in discontinuous conduction mode

Abstract

Emerging technologies in the field of integrated circuits demand wider conversion ratios with a substantial reduction in size and weight. Quadratic buck converter is a popular choice for such an application which is investigated under voltage-mode pulse train control operating in discontinuous conduction mode. The combination of high-power control pulse P H and low-power control pulse P L in a control pulse repetition cycle which has a significant effect on the control performance of the system is studied. For a reliable design, a complete assessment of its dynamics under all possible operating conditions is essential for its safe operating horizons. Computer simulations are performed to capture the periodic transformation undergone due to border collision bifurcation. However, the stable periodic operation is examined with the supporting evidence of movement of eigenvalues from 2D discrete-time model and maximal Lyapunov exponent obtained using QR factorisation method for the variation in the input voltage and the load conditions. An experimental setup is also built to verify the system dynamics which are observed in simulations and analytical results.