Current-Sensorless Robust Sliding Mode Control for the Interleaved DC-DC Boost Converter

Abstract

A current-sensorless, PWM-based robust sliding mode control strategy for the interleaved DC-DC boost converter is proposed that eliminates the need for leg or input current sensors and requires only output-voltage measurement. The proposed extended state estimator maps the multi-phase converter to a mono-phase equivalent, successfully absorbing structural phase asymmetries and parasitic variations into a single lumped uncertainty term. This observer simultaneously estimates the derivative of the output voltage alongside the composite lumped uncertainty, which includes inductor parasitic resistances, parameter variations, input voltage and load changes. A systematic parameter-tuning procedure based on estimator pole placement and open-loop bandwidth guidelines guarantees a critically damped dominant estimation response. Comprehensive multi-case simulations validate the closed-loop system under parametric uncertainties and parasitics, severe unbalanced operating conditions of the two phases, load resistance and input voltage changes and high-frequency noise injection.