Implementation of dual-loop controller for positive output elementary luo converter

two-loop controller has been designed for a positive output elementary Luo (POEL) converter. An H∞ controller is used in the outer loop using the loop-shaping concepts and a sliding mode control (SMC) in the inner loop for the regulation of the output voltage in spite of the perturbations in the line and load voltages. H∞ controller generates the current reference for the converter inductor current, whereas SMC forces the converter inductor current to follow the reference. A practical design that combines the loop-shaping technique with SMC to enhance robustness and sliding performance is proposed. The closed-loop characteristics of a typical low-power POEL converter with the proposed controller implemented in the actual switched model is validated through computer simulations and experimental hardware. The proposed controller is found to be superior because of its low distortion property, good regulating performance and insensitivity to load variations. Nomenclature x iL1 vC1 iL2 v0 T, state variable vector Vo, Vin, Vref instantaneous input voltage, output voltage and reference voltage iref reference