高比例可再生能源接入的输电网结构适应性指标及评估方法

Adaptability Index and Evaluation Method for Power Transmission Network Structure with Integration of High-penetration Renewable Energy

高比例可再生能源并网和交直流混联电网是未来电力系统发展的基本特征,评估不同输电网结构特别是交直流混联电网结构对源—荷双重波动的适应性,将为未来电力系统经济、安全、可靠、灵活运行奠定基础,但适应性评估难于量化且亟待一套新背景下的评价体系。首先,在分析未来高比例可再生能源接入下输电网基本结构特征的基础上给出了输电网结构适应性的定义;然后,提出一套概率化的输电网结构适应性评价指标体系,并基于蒙特卡洛模拟算法和最优经济模型提出一种实用化的适应性指标计算方法;最后,以IEEE 30节点系统作为基础网架,分别对纯交流和交直流混联电网结构适应性做出评价,同时定量研究了不同因素对结构适应性指标的影响及变化规律。算例证明适应性指标能够有效反映不同输电网结构在高比例可再生能源接入下多方面的适应能力。

High-penetration renewable energy system and AC/DC hybrid network are two main basic characteristics of future power systems.Evaluating different network＇s structure adaptability,especially for AC/DC hybrid network,is extremely important for power system to keep economical,safe,reliable and flexible when renewable energy and load both have an increasing trend of uncertainty.However,it is very difficult to evaluate the adaptability quantitatively,so that new indexes considering high-penetration are badly needed.First,this paper analyzes the basic characteristic of network structure and gives the definition of adaptability in the background of strong randomness.Then several probable indexes of structure adaptability are proposed based on the basic characteristic of adaptability.After that,apractical calculation method is put forward,which uses the Monte Carlo simulation and the optimal economic model.Finally,by using the IEEE 30-bus system as the basic network frame,an AC network and an AC/DC hybrid network are respectively evaluated,and different influencing factors of adaptability are researched to find the change regulation.The examples prove that the adaptability index can effectively reflect the adaptability of different transmission network structures with high-proportion renewable energy integration.