在再生能源併入電網後安全限制下之能源流隨機最佳化

Abstract

隨著全球已經超過140個國家和地區宣布於2050年實現「淨零排放」的目標，能源轉型成為實現這一目標的關鍵因素。這意味著各國需要大幅度減少對化石燃料的依賴，並加速發展可再生能源的技術，如風能、太陽能和氫能。然而，將再生能源整合進電網的過程中，其不確定性以及間歇性的特點，可能會對電網的穩定性和安全性造成影響。因此，本研究考量到在能源轉型初期階段的風險，提出了具備預防性以及安全性的能源流隨機最佳化模型，以確保電網在升級的過程中盡可能的不受任何負面影響，為社會提供穩定的電力。由於提出的模型具有非凸和非線性的特性，我們透過鬆弛方法把模型鬆弛成二階圓錐規劃(Second-Order Cone Programming, SOCP)問題後並使用數學優化求解器GUROBI進行求解，以驗證模型的可行性以及計算結果的真實性。在數值分析中，分別以5個匯流排以及MATPOWER的30個匯流排之能源流測試集作為驗證模型的依據，並使用了台灣彰化沿海地區的風速和太陽能輻射量作為資料來源，透過拉丁超方格抽樣方法隨機生成場景，模擬再生能源的不確定性。由於僅考慮了發電機的操作成本，再加上再生能源加入的位置為高負載地區，因此，結果顯示使用再生能源併入發電機匯流排的配置方式會比再生能源取代發電機匯流排的配置方式還要來的更低成本。

Energy transition is crucial for achieving the 'net zero emissions' goal announced by over 140 countries and regions worldwide for 2050. This means countries must significantly reduce their reliance on fossil fuels and accelerate the development of renewable energy technologies such as wind, solar, and hydrogen. However, integrating renewable energy into the power system poses challenges due to its uncertainty and intermittency, which can affect the stability and security of the power system. Considering the risks during the preliminary stage of the energy transition, we propose a preventive stochastic security-constrained optimal power flow model to ensure power system stability during upgrades. We reformulate the model into a Second-Order Cone Programming (SOCP) due to the non-convex and non-linearity of the proposed model and use the Gurobi Optimizer to verify the feasibility and accuracy. The case study utilizes power flow test cases comprising 5 buses and 30 buses of MATPOWER for validation, using wind speed and irradiation intensity as renewable energy input data sourced from the coastal areas of Changhua, Taiwan. Scenarios are randomly generated using Latin Hypercube Sampling (LHS) to simulate the uncertainty of renewable energy. Due to the consideration of only the operational costs of generators, in addition to incorporating renewable energy in high-load areas, the results indicate that integrating renewable energy into the generator bus is more cost-effective than replacing it.