Design and optimization of IGBT gate drivers for high insulation voltage up to 30kV

International audienceIn this article, a design methodology tooptimize IGBT gate drivers for high insulation voltage capability(up to 30kV) is proposed. A Pot core ferrite with circular coilstransformer is used for high insulation capabilities. Theinsulation voltage level is defined by the air gap length and thedielectric material. The pulse width modulation (PWM) signaltransmission and power transmission functions of IGBT gatedriver are studied and optimized. For both functions, theobjective of the studies is to optimize the geometric elements oftransformer and the associated electrical components by the helpof a virtual prototyping tool. Therefore, the optimization resultsare proposed under Pareto fronts: optimization objectives for aset of the barrier insulation thickness. Finally, the experimentalverifications are shown to validate the proposed methodology

On proving the absence of oscillations in models of genetic circuits

International audienceUsing computer algebra methods to prove that gene regulatory networks cannot oscillate appears to be easier than expected. We illustrate this claim on a family of models related to historical examples

Oscillations in the expression of a self-repressed gene induced by a slow transcriptional dynamics

We revisit the dynamics of a gene repressed by its own protein in the case where the transcription rate does not adapt instantaneously to protein concentration but is a dynamical variable. We derive analytical criteria for the appearance of sustained oscillations and find that they require degradation mechanisms much less nonlinear than for infinitely fast regulation. Deterministic predictions are also compared with stochastic simulations of this minimal genetic oscillator