A current-mode controlled maximum power point tracking converter for building integrated photovoltaics

This paper presents a current-mode controlled maximum power point tracking (MPPT) converter and BIPV design considerations covering the photovoltaic orientation and tilt angle. An MPPT algorithm featuring rapid convergence and steady-state accuracy is described. The power tracking performance of the proposed MPPT converter has been experimentally verified. The experimental test rig consists of a 65 W multi-crystalline PV panel with controllable illumination to emulate the changes of solar irradiance. The test rig is fitted with a FPGA-DSP controlled rapid prototyping platform for power conditioning. The current-mode control method provides better transient performance than directly perturb the duty-cycle of the converter. A step-size varies in response to the former approach and previous error ensures rapid accurate tracking following shadow effects of clouds or obstructions. The experimental results show that the proposed MPPT converter is capable of reaching the steady-state condition quickly during a transient with negligible oscillations and tracking under dynamic changes of solar irradiance efficiently.