具柔切功能太陽光電最大功率追蹤器之研製

Abstract

本文旨在研製一具柔性切換功能之最大功率追蹤器，使太陽能電池輸出能夠穩定維持在最大功率輸出，並且達到開關的柔性切換以減少損失，使轉換效率不高的太陽能電池輸出能量可以達到有效的利用。最大功率追蹤法則採取擾動觀察法，此演算法簡單且穩定，被廣泛使用在各個太陽能光電系統。最大功率追蹤器的基本結構是昇壓型轉換器型態，為了達到最大功率追蹤法則所產生的電流命令，此轉換器採取定電流控制，最後提出一柔性切換緩衝器用以減少此系統的切換損失。 使用MATLAB/simulink模擬軟體對此系統做模擬與分析，依此為根據再透過實作來實際驗證此系統的可行性，完成此最大功率追蹤器。

A maximum power point tracker with soft-switching is the purpose of this thesis. It can reduce the switching loss and achieve soft-switching by a passive snubber, and the PV cells can operate to its maximum power by having Maximum Power Point Tracking (MPPT) implemented. MPPT algorithm uses an easy and stable method named “P&O”, which is widely used in PV system. The structure of the tracker is to boost converters, by constant current control to achieve the current command from MPPT algorithm. At last a soft-switching snubber is used to reduce the switching loss. This system is simulated and confirmed by MATLAB/Simulink, and the tracker for PV systems is implemented by DSP. The experiment results will be given in this thesis.