考虑非高斯耦合不确定性的交直流配电网两阶段概率状态估计  

Two-Stage Probabilistic State Estimation for AC/DC Distribution Network Considering Non-Gaussian Coupling Uncertainties

作　　者：李幸芝 韩蓓[1] 李国杰[1] 汪可友[1] 江秀臣[1] Li Xingzhi;Han Bei;Li Guojie;Wang Keyou;Jiang Xiuchen(Key Laboratory of Control of Power Transmission and Conversion Ministry of Education Shanghai Jiao Tong University,Shanghai 200240 China)

机构地区：[1]上海交通大学电力传输与功率变换控制教育部重点实验室,上海200240

出　　处：《电工技术学报》2020年第23期4949-4960,共12页Transactions of China Electrotechnical Society

基　　金：国家自然科学基金资助项目(51877133)。

摘　　要：目前配电网中配置的量测装置种类简单且数量有限,分布式电源(DG)出力和用户负荷通常具有非高斯分布的不确定性,加剧了交直流配电网状态估计的不确定性和误差。针对这些问题的研究严重滞后于对交直流系统进行灵活调度的发展目标,因此需要研究更有效的交直流配电网状态估计方法来支撑调度系统。该文采用计及电压源换流器(VSC)损耗的模型,基于高斯混合模型(GMM)对非高斯不确定性进行伪量测建模,充分考虑交流和直流配电网间不确定性的耦合计算,提出一种交直流配电网两阶段概率状态估计算法。采用IEEE 33节点修改算例进行交直流配电网仿真,结果表明,所提两阶段算法适用于实时量测少、数据冗余度低的情况;对已有交流状态估计算法继承性好,具有实用性,未来可扩展到三相不平衡交直流配电网状态估计中。At present,real-time measurements implemented in distribution networks only have simple structures and limited quantities.The randomness from DGs(Distributed Generations)and loads are usually non-Gaussian,which exacerbate the uncertainties and errors of state estimations in hybrid AC-DC distribution network.These problems seriously inhibit the development of flexible management in AC-DC distribution networks.Therefore,it is necessary to develop more effective methods for ACDC distribution network state estimations to support hybrid distribution network management.This paper proposes a two-stage probabilistic estimation for AC-DC distribution network.The proposed method is based on voltage source converter(VSC)loss model and Gaussian mixture model(GMM).It gives full consideration of the coupling uncertainties between AC and DC distribution subnetworks.Simulations conducted based on the modified IEEE-33 node AC-DC distribution network show that the proposed two-stage estimation method is suitable for situations with limited real-time measurements and low data redundancy.The method can be practically implemented in existing AC state estimation modules.It can also be extended to consider three-phase unbalanced AC subnetwork in the future.

关 键 词：伪量测建模 交直流配电网 概率状态估计 分布式电源 高斯混合模型 

分 类 号：TM734[电气工程—电力系统及自动化]