Reduction of Output Impedance of Buck Converter with Genetic Algorithm

This paper introduces a technique to reduce the output impedance in the PWM buck converters with voltage-mode control (VMC) without requiring low Equivalent Series Resistance (ESR) output capacitors. Proposed technique uses the infinity norm ( ) to convert the problem into an optimization problem. Obtained optimization problem is solved with the aid of Genetic Algorithm (GA). The proposed technique is applied to a sample buck converter operating in Continuous Conduction Mode (CCM). Simulink simulation is used to test the suggested method. Simulation results showed a considerable decrease in the low frequency region of output impedance. Such a decrease in output impedance is very desired for low voltage high current loads like computer CPU’s.

Keywords:

DC-DC converters, load transients, output impedance of buck converter State Space Averaging (SSA).,

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