In this paper, the design, control and stability analysis of the inverter-based power conditioner - which is connected to the low voltage grid via an LCL filter - is presented to manage the power flow of the Proton Exchange Membrane Fuel Cell (PEMFC). Since the PEMFC-generated voltage is lower than the grid voltage, a DC-DC converter is utilized to increase the PEMFC output voltage. The LCL filter is employed to improve the injected current quality and to reduce the inverter output voltage distortions. This filter can cause resonance and system instability. The current double feedback control method, which uses inverter side and grid side currents as feedback current, is suggested to dampen the resonance and improve harmonic eliminations. The suggested power conditioner system is simulated in MATLAB/Simulink to verify the model performance and the suggested control method. The obtained results show i) good performance of the suggested system in managing PEMFC power flow into the grid, ii) high quality of the injected current and iii) system stability against the grid impedance change disturbances.
Key words: Proton exchange membrane fuel cell; LCL filter; Current double feedback; Stability analysis.
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