隨著能源結構的改變，以及環保意識的抬升，全世界逐漸轉而發展不同類型的再生能源，以取代傳統容易導致環境汙染，傷害大自然的發電方式如：火力發電、核能發電等。由於全世界每年建置再生能源之比例逐年升高，故電網中有大容量或許多單相再生能源併接至配電系統時，將會使系統產生三相不平衡的現象；台電公司在配電系統的規劃設計中，大量設置開Y - 開△變壓器組，此設計方式雖可有效降低配電變壓器的設置投資成本，但也增加配電系統不平衡的程度，當電力系統的不平衡程度達到或超過相關標準時，或者將可能使系統無法允許更多的再生能源併入，對再生能源的發展構成極大的阻礙，同時電力系統的三相不平衡現象也會對電力系統及設備產生許多不良的影響。
有鑑於此，本文旨在研究儲能系統於三相不平衡改善之應用，設計電網控制器用於調度三個單相功率轉換器，並組成三相電力系統，以利改善三相不平衡之狀態。其功能包含蒐集電網的電力資訊，並透過計算求得各相所需補償之參數值，並控制三個單相功率轉換器間互相配合輸出。本研究採用實際案場所設計之結構進行模擬測試，藉由模擬結果驗證該方法的有效性。

Along with the alternative approaches to energy configuration and the rising awareness of environmental protection, each country gradually turns into developing different types of renewable energy to replace the traditional methods of power generation, such as thermal power generation and nuclear energy generation. As the proportion of renewable energy is increasing year by year, both high capacity and a great deal of single-phase of renewable energy are expected to be connected to the grid, but unfortunately, it occurs a three-phase unbalance challenge to the system. In the planning settings of the power supply and distribution system provided by Taiwan Power Company, numerous open Y- open △transformers are used. Although this design can effectively reduce the investment cost of distribution transformers sets, it increases the degree of unbalance in power distribution system. Either the level of unbalance meets or exceeds the standards, or the failure of renewable energy to be integrated into the power systems will severely impede the development of renewable energy and further adversely affect power systems and equipment.
In the light of the current three-phase unbalance problem, the purpose of this study is to design a grid controller for dispatching three single-phase power converters in order to reform the three-phase power system avoiding the unbalance tendencies. The major contribution of this is to provide and control the output of three single-phase power converters by collecting the power-grid information to calculate the parameter values for compensating in each separate phase. In this study, the energy storage system adopted from the industry is simulated and tested under practical condition, and the effectiveness of the proposed method is verified by the simulation results.

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