Enhancing Stability and Control of HESS in DC Microgrid Feeding CPLS: An Optimized Terminal Sliding Mode Approach

Abstract

This paper presents the integration of hybrid energy storage systems (HESS) with a DC microgrid network that feeds constant power loads (CPLs), which are challenging to manage due to their destabilizing nature. Single-inductor full-bridge buck-boost converters integrate the HESS with the microgrid. An improved droop controller is proposed for efficient power sharing within the HESS and an optimized terminal slidingmode controller for low-level switching control. The optimized sliding mode controller enhances performance and ensures largesignal stability of the closed-loop system, demonstrated through Lyapunov theory. The proposed method is validated via MATLAB/Simulink simulations and comparative analysis with SMC and integral sliding mode control (ISMC) Finally, real-time performance is evaluated using controller hardware-in-loop (C HIL) tests with Typhoon HIL and TI C2000 microcontrollers.