本文旨在設計及研製單相及三相的四支路電感耦合換流器，具有並聯多階位準的功能，適用於大電流換流器應用場合。採用耦合電感抑制循環電流，並使電路能工作較高基本頻率並提高動態響應。系統採用電壓及電流閉迴路控制，使輸出電壓接近實際命令值，並回授各支路電流與其平均值完成各支路電流平衡控制，達到電流平衡目的，提升整體電路穩定度。使用四組交錯式脈波寬度調變控制，以降低輸出的諧波含量，提升整體電力品質。本系統採用德州儀器之數位信號處理器TMS320F28075作為控制的核心，內建有PWM模組，其控制系統皆由軟體程式完成，以減少實體硬體電路。
本文已建立四支路電感耦合換流器的模式，以及單相及三相電壓及電流閉迴路控制策略，並以Matlab/Simulink應用軟體模擬，驗證系統控制策略之可行性。本文已完成單相系統的輸出功率為3kW及三相系統的總輸出功率為6kW，系統頻率範圍60~200Hz的實體製作。單相系統頻率為60Hz輸出功率為3kW的實測結果，輸出電壓總諧波失真率為2.40%；輸出功率為1kW頻率為200Hz時，輸出電壓總諧波失真率為1.40%。三相系統實測方面，頻率為60Hz，總輸出功率為6kW時，輸出電壓總諧波失真率為1.13%；總輸出功率為3kW其頻率為200Hz時，輸出電壓總諧波失真率為1.68%。單相及三相系統的電流平衡指標 均低於3%，每支路電感電流達到均流效果。單相系統在3kW操作其效率為97.8%，三相系統在6kW操作其效率為98.6%。從實測結果驗證本文系統與控制策略之可行性。

This thesis aims to design and develop single-phase and three-phase inverter with four-branch coupled inductor, which have the function of parallel multi-level levels, and are suitable for high-current inverter applications. Using coupled inductors to suppress circulating currents, and enable the circuit to work at a higher fundamental frequency and improve dynamic response. The system adopts voltage and current closed-loop control to make the output voltage close to the command value, and feedback the current of each branch and its average value to complete the current balance control of each branch to achieve the purpose of current balance and improve the stability of the system. Four sets of interleaved pulse width modulation control are used to reduce the output voltage harmonic content and improve the overall power quality. This system uses the digital signal processor TMS320F28075 of Texas Instruments as the core of the control, with a built-in PWM module, and the control system is completed by software programs to reduce hardware circuits.
This system has established the four-branch inductively coupled converter mode, as well as single-phase and three-phase voltage and current closed-loop control strategies, and simulated it with Matlab/Simulink application software to verify the feasibility of the system control strategy. This system has completed the single-phase system with the output power of 3kW and a three-phase system with a total output power of 6kW, and the range of system's fundamental frequency is 60~200Hz. When the single-phase system's frequency is 60Hz and the output power is 3kW, the total harmonic distortion of the output voltage is 2.40%; when the output power is 1kW and the frequency is 200Hz, the THDv is 1.40%. For the three-phase system, when the frequency is 60Hz and the total output power is 6kW, the THDv is 1.13%; when the total output power is 3kW and the frequency is 200Hz, the THDv is 1.68%. The current balance indicators of single-phase and three-phase systems are both less than 3%, and the inductor current of each branch achieves a current-sharing effect. The efficiency of single-phase system is 97.8% in 3kW operation, and the efficiency of three-phase system is 98.6% in 6kW operation. The results verify the feasibility of the system and control strategy in this thesis.

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