含构网型新能源发电单元的孤立电网暂态稳定性提升策略  

A transient stability improvement strategy of isolated power grids with grid-forming-based renewable energy power generation units

作　　者：刘瑞平 袁亮[1] 胡铭欣 韩华[1] 刘绪斌 LIU Ruiping;YUAN Liang;HU Mingxin;HAN Hua;LIU Xubin(School of Automation,Central South University,Changsha 410083,China)

机构地区：[1]中南大学自动化学院,湖南长沙410083

出　　处：《电力科学与技术学报》2024年第6期152-161,共10页Journal of Electric Power Science And Technology

基　　金：国家自然科学基金(52307156);长沙市自然科学基金(kq2208279)。

摘　　要：构网型新能源发电单元能为孤立电网提供惯量支撑,但在故障时存在暂态稳定性问题。为解决此问题,研究了构网型新能源发电单元无功外环对孤立电网暂态稳定性的影响机理并提出相应的致稳策略。首先,采用李雅普诺夫直接法探究构网型新能源发电单元输出端电压的稳定边界;其次,提出一种基于输出端电压稳定边界的自适应下垂系数的综合控制策略,该策略不仅能够维持系统功角稳定,还能限制故障电流,而且在保证逆变器安全的同时,可提升系统的暂态稳定性;最后,在MATLAB/Simulink中搭建电磁暂态仿真,仿真结果验证了理论分析的正确性以及所提暂态稳定性提升策略的有效性。The grid-forming-based renewable energy power generation units can provide inertial support to isolated power grids,but they face transient stability issues when faults occur.To address this issue,the impact mechanism of the reactive power outer loop of the grid-forming-based renewable energy power generation units on the transient stability of isolated power grids is studied,and corresponding stability improvement strategies are proposed.Firstly,the Lyapunov direct method is employed to explore the stability boundaries of the output-end voltage of the grid-forming-based renewable energy power generation units.Secondly,a comprehensive control strategy with an adaptive droop coefficient based on the stability boundaries of the output-end voltage is proposed.This strategy not only maintains system power angle stability but also limits fault currents.It enhances the transient stability of the system while ensuring the safety of inverters.Finally,electromagnetic transient simulations are conducted by using MATLAB/Simulink,which validate the correctness of the theoretical analysis and the effectiveness of the proposed transient stability improvement strategy.

关 键 词：孤立电网 构网型 暂态稳定性 李雅普诺夫直接法 下垂系数 

分 类 号：TM712[电气工程—电力系统及自动化]