光伏系統在遮陰情況下利用改良式粒子群優化演算技術之最大功率點追蹤

Maximum Power Point Tracking of Photovoltaic Systems with Modified Particle Swarm Optimization Technique Under Partial-Shading Conditions

杜柏憲(Po-Hsien Tu)

指導教授 ： 林容杉

國立暨南國際大學/科技學院/電機工程學系/碩士(2016年)

摘要

本論文的主要目的是開發光伏系統在局部遮陰條件下的最大功率追蹤器。由於天氣是不可預測的，所以系統有可能存在局部和全局的最大功率點。因此，我們必須在遮陰條件下追蹤到全局最大功率點，為了使我們的光伏系統能提供有效的最大功率輸出。
首先，我們建立光伏陣列系統數學模型，並且調查分析在部分遮陰以及沒有遮陰條件下的電壓和功率的輸出。然而，在遮陰條件下的光伏陣列輸出會產生多個最大功率點，所以我們必須找出合適的全局最大功率點追蹤技術。
我們提出一個新的概念來改良傳統的粒子群優化法並加強算法開發能力和提高系統的性能。我們除了使用線性遞減慣性權重外，還應用非線性適應學習因子增強追蹤能力。它能夠避免陷入局部最佳解，並提供系統具有更精確的收斂。實驗結果表明，改良後的粒子群算法在遮陰條件下的全局最大功率點追蹤具有較高的精確度與收斂性。

關鍵字

光伏系統 ； 最大功率點追蹤 ； 粒子群優化法

並列摘要

The major target of this thesis is to develop the maximum power tracker of photovoltaic (PV) systems under the partial-shading conditions. Since the weather is unpredictable, there might exist local and global maximum power points (MPP) in the systems. Therefore, we must be able to track the global MPP under the partial-shading conditions in order to make our PV systems offer effective maximum power output for obtaining optimal system performance.

First of all, the mathematical model is established for a PV array system to investigate and analyze the voltage and power output under partial-shade and non-partial-shade conditioning. However, the output power of PV systems could have various MPP under partial-shading conditions, so we have to determine an appropriate technology for the tracking control of global MPP.

A novel concept is presented to modify the traditional particle swarm optimization method for strengthening algorithm capability and improving the system performance. In addition to using linear decreasing inertia weight, we apply nonlinear adapting learning factors for enhancing the tracking ability. It can avoid falling into local maximum solutions and provide the system to have more accurate convergence. As a result, the simulation results show that the modified particle swarm optimization has the potentials to track the global MPP with accurate rate of convergence under partial-shading conditions.

並列關鍵字

Photovoltaic systems ； Maximum power point tracking ； Particle swarm optimization

參考文獻

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