Summary: | 碩士 === 長庚大學 === 電機工程學系 === 98 === In this thesis, we proposed and implemented a 12-bit area-efficient folded all-digital maximum power point tracking (MPPT) chip based on gain-adaptive perturb-and-observe algorithm for photovoltaic energy conversion system. Alternative to DSP or micro controller, realizing the MPPT algorithm by using ASIC can achieve higher energy conversion efficiency, lower power consumption and smaller chip area. By using gain-adaptive perturb-and-observe MPPT algorithm, it can overcome the periodic perturbation issues in conventional perturb-and-observe MPPT algorithm, which can save overall system power consumption. By using the proportional integral controller, we can track the maximum power point fast and stable. As compared with the conventional perturb-and-observe MPPT algorithm under high intensity sun illumination, the gain-adaptive perturb-and-observe algorithm can track three times faster. As compared with the conventional perturb-and-observe MPPT algorithm under low intensity sun illumination, the gain-adaptive perturb-and-observe algorithm can perform the same power conversion efficiency. By using folding VLSI architecture, we can save a 77% chip area and 70% power consumption in realizing the MPPT algorithm. Finally, our proposed MPPT chip is implemented in TSMC0.18μm process, while the chip area is 0.85mm*0.79mm and the power conversion efficiency is 97.9%.
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