Impact of Chaos Anticontrol and Switching Frequency Variation on MOSFET Junction Temperature and Lifetime

Generating chaos from originally non-chaotic systems is a promising issue. Indeed, chaos has been successfully applied in many fields to improve systems performance. In this work, a Buck converter is chaotified using a combination of the switching piecewise-constant characteristic and of the anticontrol of chaos feedback. For electromagnetic compatibility compliance reasons, this feedback control method is able at the same time to achieve low spectral emissions and to maintain a small ripple of the output voltage and of the inductance current. This new feedback implies a fast and non-linear switching action of the Buck Mosfet on a period of the ramp generator. Thus, it is essential to analyze its thermal performance. This is why we propose an original analysis of the influence of anticontrol of chaos and switching frequency variation on the junction temperature: we investigate the correlation between the lifetime of the power electronic switching component and its thermal stress due to the addition of chaos. It appears that the reduction of the current ripple does not degrade the Mosfet junction thermal performances despite the fast switching of the Mosfet. Furthermore, an insignificant degradation of the Mosfet lifetime is indicated for chaotic behavior versus periodic behavior. Thus, this leads to the conclusion that using anticontrol of chaos produces insignificant accumulated fatigue effect of the Buck converter’s semiconductor.