主动配电网孤岛划分的混合整数规划模型

摘要

Reactive power balance is an important factor restricting the feasibility and safety of islanding. As the main reactive power source of the active distribution network,the power characteristics of the distributed generation( DG)are often neglected so that it is difficult to satisfy the power balance of islands. In order to conciliate accuracy and computational performance,a mixed integer programming model for islanding partition of the active distribution network is established. The P-Q capability limits of DGs are linearized based on the analytic geometry model,which can consider the power characteristics of the doubly-fed wind generator,the synchronous generator,and the voltage source inverter-based generator. The product terms between the voltage and the power in the Kirchhoff ’s current equations are linearized using the bi-linear model. The separation model is used for solving the variations of the islanding network topology and the load shedding problems. The square terms are linearized by adopting the special ordered sets-2. The numerical results of case studies demonstrate that the proposed model is of high accuracy and good adaptability;and DG’s operation satisfies its power characteristics and practical engineering. Furthermore,the rationalizing segmentation is the key to the feasibility of the island scheme and the solution of proposed model, whose recommended value is more than 12. But there is no monotonous relationship between segments and CPU time.%无功平衡是制约孤岛可行性和安全性的重要因素，而作为主动配电网主要无功电源的分布式电源自身功率特性常常被忽视，使孤岛功率平衡难以满足。为调和模型求解速度与准确度的矛盾，构建了一种主动配电网孤岛划分的混合整数规划模型。该模型基于解析几何模型线性化DG的P-Q功率极限，有效计及了双馈风力发电机、同步发电机和逆变型发电机的功率特性；通过双线性模型线性化含电压功率乘积项的基尔霍夫电流方程；分离约束模型解决孤岛网络拓扑变化和负荷切除的问题；采用特殊排序集合2线性化平方项。通过算例验证了所提模型，结果表明：所提模型求解准确度高、适应性好，DG运行点满足功率特性，符合工程实际；合理化分段数取值是保证孤岛方案可行性和模型求解准确度的关键，推荐取分段数大于等于12，但其与求解CPU时间无单调关系。