再生能源的使用率日益增加促進分散式電源形成微電網，微電網中最核心的設備就是電網形成變流器。電網形成變流器應能夠在離網並聯模式或併網模式下運行。本論文旨在研製單相全橋式變流器，使用電網形成變流器的控制架構實現變流器離網並聯控制、併網功率控制。變流器並聯系統使用兩台單相全橋式變流器與垂降控制的架構，實現變流器根據負載的功率需求調整變流器的輸出。此外，本論文採用虛擬阻抗的方法抑制因輸電線阻抗相異造成的循環電流過大的問題。併網控制部分實現注入實功率控制與低電壓穿越控制。為了精進控制效能，本論文使用PSIM模擬軟體設計硬體電路參數、控制電路參數，並使用MATLAB Simscape最佳化雙回路控制中的PI參數。實作以單相全橋式變流器搭配數位訊號處理器TMS320F28335驗證其效能。

The increasing use of renewable energy is promoting the distributed generation to form microgrids. Within microgrids, the most crucial component of power electronic equipment is the grid forming inverter. The grid forming inverter should be able to operate either in off-grid paralleling mode or grid-tied mode. This thesis aims to develop single-phase full-bridge inverters, utilizing the control architecture of grid-forming inverter to achieve off-grid paralleling operation and grid-tied operation. The parallel inverter configuration employs two single-phase full-bridge inverters with droop control to adjust the power outputs based on load demand. A virtual impedance method is introduced to suppress circulating currents between two parallel inverters due to different line impedances. When the inverter operates in grid-tied mode, a low-voltage ride-through control is introduced to smoothly handle voltage transients. To achieve better control performance, this thesis employs PSIM simulation software to design control loop parameters. Furthermore, the MATLAB Sim-scape is utilized to optimize the PI parameters in dual-loop control. The design is validated using a single-phase full-bridge inverter with the digital signal processor TMS320F28335.

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