電壓穩定度之發生為電力系統因事故或無法預測的負載增加。透過量測從工作點到電壓崩潰點距離的負載裕度的概念來達成此目標。為了強化多重操作條件下的系統負載裕度使系統達到穩定的負載裕度，本論文利用連續線性規劃法探討預防控制與緊急控制，並且以Matlab軟體與PSAT軟體實現強化控制與預防控制，整體程式包含三部分：第一部份透過連續潮流分析找到電力系統中初始事故與每個斷線事故的負載裕度，接著則求出每種控制器在崩潰點時對於負載裕度的敏感度，本論文討論到的控制器，包含實功/虛功發電機、負載升壓變壓器、並聯電容器、卸載等。第二部分為處理故障事故的篩選與排序，透過故障事故篩選，將故障事故有系統地分類，可以提高控制法的運算效率，而在預防控制與強化控制的過程中，將會探討大多數的故障事故。最後部分是將預防控制與強化控制的問題，轉成連續線性規劃的數學問題來探討，有別於以往的潮流最佳化解決系統負載裕度強化問題，本論文討論的連續線性規劃法也可以透過IEEE的14節點電力系統模型與39節點電力系統模型來做模擬驗證，並且透過與商用軟體-電壓穩定度評估(Voltage Stability Assessment)驗證並比較其模擬結果，證實本篇論文可以透過連續線性規劃法，在探討預防控制與強化控制問題中找到更適合的方法。

Voltage stability occurs when power systems suffered severe contingency or unpredicted load increasing. In order to quantity to voltage instability, the concept of the loading margin has been proposed to measure the distance from the current operating point to the voltage collapse point. This thesis will study preventive and enhancement control actions via the sequential linear programming(SLP) techniques enhance the load margin. The prototype simulation program for preventive control and enhancement control has been implemented in Matlab. The entire program consists of three tasks: First, the continuation power flow will be explored to obtain load margins for the base case and N-1 contingencies. The load margin sensitivity with respect to various control actions, such as active/reactive power generations, LTC transformer taps, shunt capacitors and loads shedding, will also be derived. In the second task, contingency ranking will be performed. The most severe cases will be chosen for studying preventive control and enhancement control. Finally, both preventive control and enhancement control problems will be formulated as SLP problems. Both IEEE 14-bus and 39-bus systems have been tested to validate our methods. Comparison studies between the proposed method and the commercial software VSA demonstrate that the proposed method can indeed find proper control actions preventive control and enhancement control problems.

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