用於太陽能發電系統之複合式最大功率追蹤器的研製

Design and Implementation of Hybrid Maximum Power Point Tracker in Solar Power System

蘇郁珺(Yu-Chun Su)

指導教授 ： 歐勝源

國立臺北科技大學/電資學院/電機工程系 電力電子產業研發碩士專班/碩士(2010年)

摘要

本論文提出採用擾動觀察法與開路電壓法完成太陽能發電系統之複合式最大功率追蹤法則。為了改善擾動觀察法之擾動速度，先利用開路電壓法得知最大功率點所相應之電壓值，使DC-DC轉換器之輸入電壓到達所計算之最大功率點電壓，再使用擾動觀察法來追蹤最大功率點。利用所得知之最大功率點電壓值計算出一定範圍，若其後所感測之電壓落在該範圍值內，則使用擾動觀察法實現最大功率追蹤功能；反之，若未落在範圍值內，則使用開路電壓法實現最大功率追蹤功能。為了進一步降低一般擾動觀察法在到達最大功率點時的振盪現象所導致的損失，且藉由太陽能板實測得知當將達到最大功率點與大於最大功率點之範圍內，其功率變化率小，因此利用此特性，當觀察計算其功率到達該範圍內時，設定該次責任週期量與上次責任週期相同，藉以降低擾動觀察法於最大功率點上之擾動損失。最後，使用具有內建式ADC與PWM功能之8bit HT46F49E MCU數位控制器來實現本論文所提最大功率追蹤法則，並藉以驗證所提之功能。

關鍵字

太陽能電池 ； 最大功率點追蹤 ； 升壓型轉換器 ； 擾動觀察法 ； 開路電壓法

並列摘要

This thesis provides a hybrid maximum power point tracking method based on both perturbation and observation method and constant voltage method in solar power system. To improve the tracking speed of perturbation and observation method for the power disturbance, the constant voltage method is initially used to retrieve the voltage corresponding to maximum power point. When the input voltage of used converter reaches the calculated voltage, the perturbation and observation method starts up instead. Furthermore, a value range is defined by the calculated maximum voltages, and if the subsequently sensed voltage value falls within this range, the perturbation and observation method is still used for maximum power tracking. On the other hand, if the sensed voltage value does not fall within the range of values, the constant voltage method is reused to track the maximum power point again. That is, the proposed method will omit small power perturbation to decrease the tracking time and oscillation phenomenon at maximum power point by perturbation and observation method, and therefore the loss reduction. To take advantage of this feature, the duty cycle is set as the same as the previous duty cycle while observing to calculate the power to reach the predetermined range. The digital controller HT46F49E MCU is used to implement the proposed maximum power point tracking method and Boost converter is utilized to act the power topology, and experiments conform the predetermined results.

並列關鍵字

Photo-voltic ； Maximum power point tracking ； Boost converter ； Perturbation and observation ； Open-circuit voltage measurement

參考文獻

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