本文主旨為研究三主動全橋式轉換器於太陽能儲能系統之應用，並深入分析三主動全橋式轉換器架構之優劣。全橋式轉換器由於寄生元件之因素產生電流偏移，若無針對電流偏移情況修正，將引起電感飽和、虛功率過大、無法達成零電壓切換等問題，導致轉換器效率大幅下降。本文針對電流偏移進行分析、模擬，並提出電流平衡控制改善電流偏移，達到減少虛功率面積、減少元件影響以及改善零電壓切換範圍。
本文提出電流互感器、隔離變壓器以及儲能電感等元件設計方式，並且製作出實體電路進行測試。最終實際完成一台輸入電壓為170 Vdc至280 Vdc、輸出電壓為360 Vdc以及輸出功率為10 kW的直流-直流三主動全橋式轉換器。功率級主要包含三組全橋電路、三個儲能電感、一個電流互感器以及一個三繞組的變壓器。藉由電流互感器偵測輸入電流作為控制器主要回授之變量，利用此變量計算電流偏移量，並使用數位訊號處理器進行控制，達到電流平衡控制。經由實驗結果顯示轉換器在不同輸入電壓為170 V、220 V以及280 V，不同的負載條件下，兩組輸出電壓均可達到360 V。本文所採用之電流平衡控制能有效改善電流偏移情況以及轉換器整體效率，且效率最高可達97.5%。

The main purpose of this thesis is to study the application of triple active bridge converter in solar energy storage system and analyze the advantages and disadvantages of triple active bridge converter. Full bridge converter generates current bias due to uncontrollable factors. If there is not any correction for current bias, it will cause problems such as inductance saturation, excessive negative power, and cannot achieve zero voltage switching, leading to the lower efficiency of the converter. The current balancing control is proposed to improve the current bias issue. The three main concepts will be improved: including reducing the negative power area, the influence of components, and improving the zero-voltage switching range.
Considering the relevant specification of solar energy storage system. A DC-DC triple active bridge converter with an input voltage of 170 Vdc to 280 Vdc, two output voltages of 360 Vdc, and output power of 10 kW was completed. The power stage mainly consisted of three full bridges, three inductors, a current transformer, and a three-winding transformer. The current transformer detects the input current as the main feedback variable of the controller. Using this variable to calculate the current bias and a digital signal processor can achieve current balancing control. The experimental results show that under different input voltages (170 V, 220 V, 280 V) and different load conditions, the output voltages of the two ports can reach 360 V. The current balancing control used in this article can improve the current offset and the highest efficiency can reach 97.5%.

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