結合降壓型直流對直流電源轉換器之太陽能板最大功率追蹤控制

Abstract

由於太陽能光伏發電系統經常會有低功率與隨時會變化的太陽光照射問題，為了解決這些問題，通常採用最大功率點追踪技術(Maximum Power Point Tracking, MPPT)以維持太陽能板的最大功率輸出。本論文提出三個不同最大功率點追踪演算法控制太陽能板的最大功率輸出，分別為可變結構法(Variable Structure method)，擾動觀察法(Perturbation and Observation algorithm, P&O)和增量電導法(Incremental Conductance algorithm, INC)。經由模擬結果顯示，三個不同最大功率點追踪演算法均可成功的追踪到太陽能板的最大功率點(Maximum Power Point)，而其中以增量電導法的穩定度最佳。在實務驗證過程當中，擾動觀察法和增量電導法的實驗結果與理論相符合，並穩定的將輸出功率維持在最大功率點;而可變結構法會因為電流感測器的解析度不夠，難以量測太陽能板輸出電流之微小變化量，導致無法成功追蹤其最大功率點。

Since photovoltaic (PV) systems often encounter two problems: low power efficiency and variable solar irradiation. In order to resolve these problems, PV systems must adopt maximum power point tracking (MPPT) technique to maintain the peak output power of the solar module. This thesis proposes three of the MPPT algorithms to control the peak output power of the solar module. These MPPT algorithms are Variable Structure method, Perturbation and Observation algorithm (P&O), and Incremental Conductance algorithm (INC). From the simulation results, all the MPPT algorithms could track the peak output power of the solar module successfully. The INC algorithm is better than the other two MPPT algorithms because it can stay around the maximum power point stably. From the experimental results, only the P&O algorithm and INC algorithm could reach the maximum power point, but the Variable Structure method fails in maximum power point tracking because the current sensor resolution is not able to measure the current change of the solar module.