基于李雅普诺夫函数的带锁相环的VSC大扰动稳定性判据  

Large disturbance stability criterion for a VSC with phase-locked loop based on a Lyapunov function

作　　者：李宇骏 华凤林 陆艺源 张谦 杜正春[1] LI Yujun;HUA Fenglin;LU Yiyuan;ZHANG Qian;DU Zhengchun(Department of Electrical Engineering,Xi’an Jiaotong University,Xi'an 710049,China;Electric Power Research Institute of State Grid Shanxi Electric Power Company,Taiyuan 030001,China)

机构地区：[1]西安交通大学电力工程系,陕西西安710049 [2]国网山西省电力公司电力科学研究院,山西太原030001

出　　处：《电力系统保护与控制》2023年第2期46-54,共9页Power System Protection and Control

基　　金：国家电网有限公司总部科技项目资助(5100-202055389A-0-0-00)。

摘　　要：对于带锁相环的并网VSC大扰动稳定性问题,首先依据VSC的内环电流控制和外环功率控制响应速度差异得到简化二阶非线性模型,然后分别定义了两个李雅普诺夫函数。第一个李雅普诺夫函数具有清晰的动能和势能概念,但推导的稳定域较小,第二个李雅普诺夫函数推导的稳定域较大但缺乏清晰的物理概念。最后结合这两个李雅普诺夫函数,得到实用的稳定性判据,兼具明确的物理意义和较宽的稳定域。如果在系统最后一次动作时已知锁相环状态量,则可以预测系统稳定性。仿真结果验证了该判据的正确性。To study the large disturbance stability of a grid-connected VSC with phase-locked loop, a simplified second order nonlinear model of a VSC is established based on the difference of response speed between inner loop current control and outer loop power control, and two Lyapunov functions are separately defined. The first Lyapunov function has clear kinetic energy and potential energy concepts but a small stable region, while the second Lyapunov function has a wider stable region but lacks clear physical concepts. Combining the two Lyapunov functions, a practical stability criterion is obtained, one which has both clear physical concepts and a relatively large stable region. If the state of the phase-locked loop is known at the time of the system’s last operation, the stability can be predicted. The simulation results well verify the accuracy of the derived stability criterion.This work is supported by the Science and Technology Project of the Headquarters of State Grid Corporation of China(No. 5100-202055389A-0-0-00).

关 键 词：并网VSC 锁相环 大扰动稳定性 LYAPUNOV函数 

分 类 号：TM712[电气工程—电力系统及自动化]