Dual-Loop Estimation Based Adaptive Controller for Microgrid Connected Boost Converters

DC microgrids are an excellent solution to integrate modern power generation and consumption with legacy infrastructure. Tightly regulated converters connecting ac and dc loads to the dc bus challenge the stability of the microgrid by showing a constant power load (CPL) behavior. This work proposes a dual-loop estimation based adaptive controller (DLEAC) for converters regulating the dc bus voltage, and a novel nonlinear estimator to identify the CPL and resistive power consumption components. The controller combines a feedback linearization control for the current loop with a traditional dual-loop proportional-integral control structure in which the proportional and integral gains of the voltage controller vary according to the estimated load power, allowing it to maintain constant dynamics at all operating conditions. The proposed methods show low computation complexity and are suitable for implementation on industry-standard microcontrollers. Detailed mathematical procedures, as well as comprehensive simulation and experimental validation are included in this article.