Adaptive Lyapunov–Hamiltonian Control Law for Multi-Cell Step-Up Fuel Cell Converters to Enhance DC Microgrid Stability Under Constant Power Loads

This paper proposes an adaptive Lyapunov–Hamiltonian control law for multi-cell interleaved boost converters in fuel cell (FC)-based dc microgrids under constant-power loads (CPLs). Conventional cascade proportional–integral (PI) controller can suffer from degraded damping, oscillation, or chattering when CPL effects become dominant. Using the port-Hamiltonian framework, the proposed method directly links the Lyapunov function to the system Hamiltonian, thereby ensuring large-signal stability through energy shaping and damping injection. Unlike earlier Hamiltonian-based methods, it avoids complex adaptive interconnection gains and introduces an adaptive inductor-current reference generation mechanism requiring only three physically meaningful tuning gains. The method is validated experimentally on a 2.5 kW two-cell interleaved PEMFC boost converter and further compared, through 50 kW simulations, with cascade PI and cascade sliding mode (SM) controllers. Results demonstrate effective dc-bus voltage regulation, balanced current sharing, fast recovery, and oscillation-free operation, with improved damping and robustness under severe CPL disturbances.