基于混合势函数法的并网型直流微电网大扰动稳定性分析  

Large Disturbance Stability Analysis of Grid-connected DC Microgrid Based on Mixed Potential Function Theory

作　　者：武颖 徐永海 王莹鑫 陈林 WU Ying;XU Yonghai;WANG Yingxin;CHEN Lin(State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources(North China Electric Power University),Beijing 102206,China)

机构地区：[1]新能源电力系统全国重点实验室(华北电力大学),北京102206

出　　处：《华北电力大学学报(自然科学版)》2025年第1期44-55,共12页Journal of North China Electric Power University:Natural Science Edition

基　　金：新能源电力系统国家重点实验室(华北电力大学)自主研究课题资助(LAPS202124).

摘　　要：“双高”背景下的直流微电网呈现出非线性强、抗扰性差等特征,导致微电网在遭受大扰动时易产生电压大范围波动、失稳等问题,严重影响其安全稳定运行。为此,针对并网型直流微电网模型,提出基于混合势函数法的系统大扰动稳定性判据,并从推导过程、基本原理的角度分析其稳定性判据保守性产生的机理;针对大、小扰动稳定性的关联,对比基于混合势函数法的大扰动稳定性判据与基于Lyapunov间接法的小扰动稳定性判据,并对稳定性判据的有效性进行验证。然后,分析系统参数、线路故障等因素对系统大扰动稳定性的影响及其作用机理,为设计电压源换流器(voltage source converter,VSC)控制参数与主电路参数、确定系统稳定运行区域提供理论依据。最后,通过电磁暂态仿真验证分析的有效性。The DC microgrid,situated in the context of high penetrations of renewable energy sources and high penetrations of inverter-interfaced devices,exhibits characteristics such as strong nonlinearity and poor disturbance immunity,resulting in issues such as large-scale voltage fluctuation and instability when subjected to large disturbances,which seriously affects the safe and stable operation of the system.Therefore,we proposed a large-signal stability criterion based on the mixed potential function theory for the DC microgrid model with grid-connected VSC,and analyzed the mechanism of the conservatism of the stability criterion.Aiming at the internal correlation of large and small disturbance stability,we compared the large disturbance stability criterion and the small disturbance stability criterion based on Lyapunov indirect method,and verified the validity of large disturbance stability criterion.Then,we analyzed the influence of system parameters,line faults and other factors on the large disturbance stability of the system and its mechanism,which provides a theoretical basis for designing VSC control parameters and main circuit parameters and determining the stable operation area of the system.Finally,the effectiveness of the analysis is verified by electromagnetic transient simulation.

关 键 词：直流微电网 大扰动稳定性 混合势函数法 Lyapunov间接法 VSC 

分 类 号：TM46[电气工程—电器]