本論文提出一種改良型極座標牛頓拉森電力潮流演算法，主要用於不平衡的輻射型配電系統。所提出的方法以牛頓拉森法為基礎，結合圖脈理論、卡農降階及注入電流技巧，將負載、並聯電容及變壓器與其他網絡元件整合到匯流排阻抗矩陣中。結合兩種判別機制及應用最佳化因子，用於估測系統之初始電壓值，所估測之初始電壓值與實際收斂解相當接近。使用五個IEEE測試系統在不同條件下進行比較。考量不同變壓器連接方式，所提方法在複雜系統的配電網路上擁有優異的收斂特性。

In this study, an improved Newton-Raphson power flow algorithm in polar coordinates is proposed for unbalanced radial distribution networks. The proposed method incorporates the graph theory, Kron reduction, and injection current methods, based on the Newton-Raphson method. The network elements, including shunt capacitors, transformers, and loads, are combined into the system bus impedance matrix. A combination of two identification processes and optimal multipliers are used to estimate the initial voltages. The estimated voltages can approximate the final converged solutions. To demonstrate the effectiveness of the proposed method, five IEEE test systems are compared under different conditions. The results indicate that the proposed method performs effectively in complex distribution networks with various transformer connections.

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