本論文實現一數位多相降壓直流轉直流電源轉換控制器。相較於單相位降壓控制器，多相系統擁有較好的電壓漣波以及良好的暫態響應。近年來，數位控制的電源轉換器挾其優勢成為研究的熱門議題，如何以數位化的方式實現多相控制器是本論文探討的重點。本控制器採用電壓模式控制，並且在系統架構上附加上電流平衡(Current Balancing)機制、適應性電壓位置(Adaptive Voltage Positioning)機制以及相位遮蔽(Phase Shedding)機制。由於多相位架構的特性，各相位元件數值或阻抗在實際情況下並非完全相等。因此相位間電流的分配成為重要的課題，本論文透過擷取電流資訊且互相比較的方式來調整送達各相位的責任週期，藉此達成電流平衡控制。此外藉由數位化後控制區塊的內部訊號進行演算，即可得知目前負載電流的狀況。可在不需偵測電流資訊的情況下以演算法實現適應性電壓位置控制。而相位遮蔽控制則可以透過關閉相位來適應負載輕重載狀況。本系統使用FPGA平台實現數位控制電路，並搭配自行設計之功率級開發板實現驗證所設計之機制結果皆為正確。

A digitally controlled multiphase DC-DC buck converter has been implemented in this thesis. Comparing to the single phase system, multiphase system has lower voltage ripple and better transient response. Also, in recent years, digitally controlled power converter becomes a hot research relying on its advantage. Therefore, this thesis focuses on how to achieve the multiphase converter by digitally. The system uses voltage control to design and three mechanisms are added into the system, which are current balancing, adaptive voltage positioning (AVP) and auto phase shedding mechanism. Due to the nature of the multiphase structure, element value or impedance cannot be exactly the same between each phase in practice. By this reason, the current sharing between each phase becomes an important issue. In this thesis, the current balance control is achieved by capturing and comparing the current between each phase, and adjusting the duty cycle. In addition, AVP mechanism can be implemented without the need for sensing or sampling the load current condition. This control architecture utilizes the error signal of the digitalized controller to obtain the current information. Moreover, the phase shedding control can promote the efficiency by shutting down one phase. The system was implemented on the FPGA platform with the power stage on PCB. Experimental results show that all the mechanisms were achieved.

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