Abstract

A study is presented of a dc-dc Boost converter whose output voltage is controlled by naturally sampled constant-frequency PWM operating in both continuous and,discontinuous made. For certain values of the circuit parameters instability occurs, Moreover, nonlinearities may produce bifurcations and chaos when parameters are varied. The goal of this paper is to delimit in the parameter space the region of period-one operation of the converter which is of practical interest for engineering design. Linear analysis and other; conventional methods are sometimes not strong enough to delimit this region, and one must rely on experimental results and careful numerical simulation. The regions are located using two different methods: a prototype which allows variation of all circuit parameters is built up and the results are checked by means of special-purpose C-code simulations, resulting in a good agreement with the experiments. Some families of curves characterize the operational regions, which border on quasiperiodic and subharmonic behavior: these bifurcation phenomena may be related to resonances and to the change of conduction mode.