Hydrogen fuel cell-inverter system for grid-connected applications: LCL filter design and optimized control strategies for power quality and standard compliance

This paper presents a hydrogen fuel cell-based inverter system designed for transformer-less grid-connected applications, emphasizing hydrogen as a sustainable energy source for decarbonizing power systems. The proposed system integrates advanced control strategies to mitigate grid-side harmonic distortion, leakage current, and common-mode voltage, ensuring compliance with international power quality standards. DC-link voltage regulation is precisely maintained, and the LCL filter is carefully optimized and designed to significantly improve dynamic performance and system stability. At a DC-link voltage of 300V, the system achieves a leakage current of 135.3 mA, significantly lower than the 225.5 mA observed with conventional methods, and well within the IEC standard threshold. It also reduces grid current total harmonic distortion to 1.84 %, compared to 2.81 % in conventional methods. Simulation and experimental results validate the system's suitability for transformer-less grid-connected applications, offering enhanced reliability and efficiency. By integrating hydrogen fuel cells with advanced inverter technologies, this work demonstrates the potential of hydrogen as a key enabler for clean energy systems, addressing the growing demand for sustainable and grid-compliant power solutions.