本論文主旨在研製一台具相移均流控制之交錯式三相Y-Δ接直流-直流轉換器，此系統由兩台三相Y-Δ接轉換器搭配交錯式控制技術所組成，交錯式開關訊號錯相為落後30度，適合應用在高壓輸入、低壓輸出、高功率的應用場合，且本論文提出之均流方法能夠降低輸出漣波。
電路架構是利用三個變壓器組成一次側Y接，二次側Δ接的方式，連接一、二次側為三個半橋電路所組成。此三相Y-Δ電路的變壓器能平均分擔總輸出功率，且根據Y-Δ接的特性，在高壓側利用Y接可降低變壓器的跨壓，在低壓側可利用Δ接來提升輸出電流。本論文首先介紹單台之三相Y-Δ接轉換器，探討三相變壓器的特性及動作原理並推導出傳輸功率及增益分析以及柔切條件。再探討並聯均流的控制種類，以及本論文提出之調變相移及頻率之均流方式，最後實作出一台輸出功率為2.4 kW的實體電路，在不同負載下皆可達成零電壓切換，整體效率最高可在94.5％。

An interleaved three-phase Wye-Delta connected converter with current sharing using phase shift control is presented in this thesis. This system is consisted of two three-phase Wye-Delta converter collaborate with interleaved control technique. The phase of interleaved driving signal is 30 degrees lagging. This topology is appropriated for high input voltage and high output power with low voltage. In addition, the balance current sharing control proposed in this thesis has the capability to reduce the output current ripple.
The power stage is consisted of three Wye-Delta connected transformers and half-bridge switches with resonant tanks. Since the output voltage is fixed, the balanced current distribution can be archived. According to the property of Wye-Delta connected transformer, using wye connection on high voltage side can mitigate the primary side voltage strass; the output current can be increased by using delta connection on low voltage side.
In this thesis, first, three-phase Wye-Delta connected converter will be introduced. Studies of characteristic of three-phase transformer, the operation principles, the power transfer function and soft-switching conditions is discussed later. Finally, a prototype with 2.4 kW output power is built and tested. The measured efficiency is above 94.5 % under a range of load conditions and all the switches can achieve ZVS.

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