P-I nonlinear control for DC-DC buck converter using a Σ-Δ modulator

This paper presents the design of nonlinear P-I control scheme for Direct Current to Direct Current (DC-DC) converter type Buck for hybrid and high power implementations using a linearized extended method. A continuous-time Σ-Δ modulator performs the over-sampled switching for the converter with benefits in the voltage ripple control, replaced a PWM modulator normally used in DC-DC converters. The proposed laws of control are simulated in Matlab Simulink and the results are shown with responses to different load values, variation in the input voltage and changes in the values of inductance and capacitance; the proposed converter achieves a fast settling time and low output voltage ripple regardless of load variations.