Photovoltaics have experienced remarkable development over the past few decades. Key to achieving this progress are high-quality testing and precise measurements. With the increasing prevalence of photovoltaics and new trends in the automotive industry, photovoltaics are gradually being integrated into vehicles, known as Vehicle Integrated Photovoltaics (VIPV). Since VIPV systems are exposed to highly dynamic conditions, standard measurement equipment has proven inadequate for conducting measurements under real operating conditions. Therefore, specialized measurement equipment that can operate under rapidly changing conditions is necessary.
In this thesis, we identified the typical conditions to which VIPV systems are exposed and determined the requirements and functionalities of a measurement system capable of performing quality measurements during typical VIPV system operations. We focused on the design and development of the power section of the system, which enables bidirectional energy conversion between the PV module and the battery and compensates for voltage drops on the connecting conductors. To ensure high adaptability, digitally controlled switching converters (buck and buck-boost) were implemented using advanced microcontroller peripheral units. These not only control the transistors and measure input and output quantities but also execute the Maximum Power Point Tracking (MPPT) algorithm.
Test results demonstrated that both designed converters operate efficiently and meet the set objectives. The buck converter proved to be suitable for voltage drop compensation, with output voltage ripple at maximum load not exceeding 36 mVrms, thereby introducing no additional noise into the system. The buck-boost converter achieves a conversion efficiency above 90 % across the entire operating range, reaching a maximum efficiency of 98,4 % under optimal conditions. The implemented MPPT algorithm, based on the perturb and observe (P&O) method, achieves a tracking efficiency of over 99 % at a tracking frequency of 100 Hz, which is a requirement for mobile VIPV systems and places it well above competing solutions on the market.
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