因應全球電力需求日益增加與地球暖化等因素，太陽光伏發電系統之使用日趨普及。有鑑於太陽光伏發電系統滲透率過高將會對配電系統電壓帶來一定程度之衝擊，進而限制太陽光伏系統的發展。一個適切的電壓控制策略將能有效地抑制過電壓問題產生，進而減少電壓衝擊並增加太陽光伏發電可饋入系統量。

本文提出一配電網路之電壓控制策略，用於高太陽光伏滲透率之系統，以降低系統電壓衝擊使其符合法定規範，同時減少不必要之太陽光伏發電饋入削減量，進而增加太陽光伏系統之利用率，提高整體之經濟效益。所提電壓控制策略主要透過有載切換開關變壓器、儲能系統與太陽光伏系統之變流器實、虛功控制搭配達成電壓控制的目的。同時為能最有效的利用光伏系統之變流器與儲能系統，本篇論文亦提出一個由粒子群演算法與動態規劃法組成之兩階式最佳化演算法，藉以決定光伏系統變流器與儲能系統最佳設置容量。

本文為驗證所提電壓控制策略之可行性，利用實際之太陽光伏發電量與負載資料分析控制策略之成效，並進一步比較所提方法與文獻現有方法之經濟效益。同時為能了解時間電價費率結構對於電壓控制策略之影響，本文分析三種不同之時間電價費率整體收益。由數值模擬結果顯示，所提之方法確實較文獻現有方法所能獲得之經濟效益更為顯著，電壓控制成效也更好。

Considering the issues of increasing power demand and global warning, the usage of renewable energy, especially the photovoltaic (PV) system, draws extensive attention. However, high penetration of PV generation seriously impacts the voltage of the distribution system, a fact which may further limit the development of PV generation systems. Therefore, an appropriate voltage-control approach is needed to effectively mitigate the over-voltage problem and increase the feed-in power of the PV system.

This thesis proposes a voltage-control strategy for the distribution system with high PV penetration system to reduce the voltage rise and comply with the voltage regulation limits. The control strategy can thus lower feed-in active-power curtailment of the PV systems, due to the over-voltage problem. The proposed voltage-control strategy is realized by managing the transformer on-load tap changer (OLTC), the energy storage system (ESS), and real and reactive power control of the PV inverters. Furthermore, to optimize capacities of the ESS and the PV inverters, a two-level optimization procedure, based on particle swam optimization (PSO) and dynamic programming (DP), is proposed in the thesis.

To verify the feasibility of the proposed voltage-control strategy, real data for PV power generation and load profile are used to analyze the effectiveness of the proposed method. In addition, comparisons are made for the proposed method and the referenced method. Besides, three different kinds of time-of-use tariff (TOU) structures are used to analyze their economic impacts. The simulated numerical results reveal that the proposed strategy can provide more effective voltage-control and increase economic benefits, as compared with the reference method.

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