Net Damping Criterion for Stability Analysis of Grid-tied VSCs in DC Voltage Control Timescale  

作　　者：Dong Wang Yunhe Hou Jiabing Hu 

机构地区：[1]School of Automation,Wuhan University of Technology,Wuhan 430070,China [2]Department of Electrical and Electronic Engineering,The University of Hong Kong,Hong Kong,China [3]HKU Shenzhen Institute of Research and Innovation,Shenzhen 518057,China [4]State Key Laboratory of Advanced Electromagnetic Engineering and Technology,Huazhong University of Science and Technology,Wuhan 430074,China

出　　处：《CSEE Journal of Power and Energy Systems》2020年第3期601-609,共9页中国电机工程学会电力与能源系统学报（英文）

基　　金：This work was supported in part by the Research Grants Council of Hong Kong under Grant GRF 17207818;the National Natural Science Foundation of China under Grant 51677160;the Themebased Research Scheme(TRS)under T23-701/14-N.

摘　　要：Stability of grid-connected VSCs in DC voltage control(DVC)timescales(i.e.,the frequency range of dynamics covering converter outer controls)has recently caught increased attention,while the existing approaches,such as eigenvalue analysis and dq-domain impedance analysis,have respective limitations on addressing these types of stability issues.This paper proposes an alternative net damping criterion dedicated for analyzing the DVC timescale stability in a multi-VSC system.This criterion is strictly mapped from the Nyquist stability criterion utilizing the gain margin concept,which preserves the advantages of the classical positive net damping criterion suggested by Canay[20]–allowing for decomposition analysis of a subsystem’s contribution to the closed-loop stability in a single-input single-output(SISO)framework,but overcomes its deficiency of possibly erroneous prediction of system dynamic behaviors.Case studies show that the proposed criterion can correctly predict some unstable conditions(e.g.,monotonic divergence)which cannot be identified by the classical net damping criterion.Additionally,the condition for when the classical criterion is available is also pointed out,the proposed criterion can also act as a complement of the classical criterion for stability examination.

关 键 词：DC voltage control timescale multiple VSCs net damping criterion stability 

分 类 号：TM712[电气工程—电力系统及自动化]