基于分段仿射阻抗模型的电压源变流器小扰动稳定域在线构造  

Online Construction of Small-signal Stability Region of Voltage Source Converters Based on Piecewise Affine Impedance Model

作　　者：马悦鑫 王鹏[1] 赵浩然 贺敬 罗嘉 王金龙 MA Yuexin;WANG Peng;ZHAO Haoran;HE Jing;LUO Jia;WANG Jinlong(School of Electrical Engineering,Shandong University,Jinan 250061,Shandong Province,China;State Key Laboratory of Operation and Control of Renewable Energy&Storage Systems(China Electric Power Research Institute),Haidian District,Beijing 100192,China)

机构地区：[1]山东大学电气工程学院,山东省济南市250061 [2]新能源与储能运行控制国家重点实验室(中国电力科学研究院有限公司),北京市海淀区100192

出　　处：《中国电机工程学报》2024年第14期5667-5679,I0019,共14页Proceedings of the CSEE

基　　金：国家电网有限公司科技项目(5100-202155481A-0-5-ZN)。

摘　　要：近年来小扰动振荡事故频发,亟需建立能反映新能源并网系统全工况的在线稳定域。小扰动在线稳定域可以为时变性和波动性下新型电力系统的安全评估和控制优化提供强有力的支撑。因此,提出基于分段仿射阻抗模型的电压源变流器(voltage source converter,VSC)小扰动稳定域在线构造方法。首先,该方法使用电压、功率和频域因子作为分区变量,离线构建VSC的分段仿射阻抗模型。在线计算时根据运行工况可以快速定位运行分区并确定对应的线性仿射模型,从而极大地提高阻抗计算的效率。其次,提出VSC稳定域边界点的双层优化模型,利用改进的广义奈奎斯特判据和复合形法进行快速求解。然后,通过改变双层优化模型的求解方向搜索边界点,基于分段拟合获取准确的边界解析式。最后,仿真算例和实验结果表明,分段仿射阻抗模型与全阶阻抗模型误差小于1%;该方法可以准确和高效地构建在线稳定域。In recent years,oscillation accidents caused by small-signal disturbance increase significantly.Establishing a stability region of grid-tied renewable energy generations under diverse working conditions is crucial for online applications.The stability region provides excellent support for the safety assessment and control optimization of power systems under time-varying and fluctuating conditions.Therefore,this paper proposes an online construction method for the stability region of voltage source converter(VSC)based on the piecewise affine(PWA)impedance model.First,this method constructs the PWA impedance model offline,utilizing voltage,power,and Laplace operators as partition variables.The partition and linear affine model can be quickly located by measuring the operating conditions during online calculations,significantly improving the efficiency of the impedance calculation.Next,a two-layer optimization model for the boundary estimation of the VSC stability region is proposed.An improved Nyquist criterion and a complex method achieve are developed to achieve a fast solution.Then,the boundary points are searched by changing the direction of the two-layer optimal model.An accurate boundary formula is obtained based on the segmental fitting method.Finally,the simulation results show that the deviation between PWA and the full-order impedance model is less than 1%.The proposed method is proven to be able to construct stability region accurately and efficiently.

关 键 词：小扰动建模 阻抗法 分段仿射 稳定域 复合形法 

分 类 号：TM46[电气工程—电器]