MPPT based sliding mode control for fuel cell connected grid system

The fuel cell has become a promising alternative to fossil sources due to its clean and efficient energy. However, it is challenging to connect the fuel cell generator to the electrical grid due to the high nonlinearity of the fuel cell. This paper deals with the problem of controlling a Proton-exchange membrane fuel cell connected to the electrical grid. In fact, a high step-up DC stage composed of an interleaved boost and a three-level boost converter, is used to ensure the maximum point power tracking, and to enhance the fuel cell voltage. Then the DC power is delivered to a half-bridge inverter and injected into the grid via an LCL filter. This study aims to design a nonlinear controller based on the sliding mode approach in order to ensure the following objectives: i) Guarantee the maximum power of the PEM Fuel cell ii) Guarantee the proper current sharing among models of IBC. iii) Regulate the interior voltage in order to improve and stabilize the FC energy. iv) Regulate the DC link voltage. v) Ensure the three-level boost series voltage balance. vi) Ensure the power factor correction. The efficiency of the proposed controller is verified and validated through numerical simulation using Matlab Simulink environment.