Open AccessInvestigation on sub‐synchronous oscillations in DFIG‐based transmission system based on improved complex torque coefficients method
Author(s) -
Wang Yijun,
Du Wenjuan,
Chen Chen,
Zhen Zijing,
Wang Haifeng
Publication year - 2019
Publication title -
the journal of engineering
Language(s) - English
Resource type - Journals
ISSN - 2051-3305
DOI - 10.1049/joe.2018.8554
Subject(s) - control theory (sociology) , doubly fed electric machine , torque , transmission (telecommunications) , transmission system , computer science , physics , ac power , power (physics) , control (management) , telecommunications , artificial intelligence , quantum mechanics , thermodynamics
The complex torque coefficients (CTC) method has been widely adopted to investigate the conventional sub‐synchronous oscillation (SSO) issues. However, the application of the CTC method is limited when large‐scale wind power generations are integrated into power systems. Therefore, in order to overcome the disadvantages of the CTC method on the aspects of frequency scan and stability determination, this paper proposes an improved CTC method based on the shaft system modal decoupling and small‐signal self‐excitation theory. The improved method is demonstrated and validated through the IEEE first benchmark power system (FBMPS). By establishing the small‐signal model of the series‐compensated DFIG‐based transmission system, the proposed method is applied to examine the SSO in a grid‐connected DFIG system. Moreover, the impacts of different parameters on the electrical damping characteristics of the system are deeply analysed. In addition, an effective VSC control strategy for suppression of the SSO in series‐compensated DFIG‐based transmission system is proposed.