Journal
INTERNATIONAL JOURNAL OF ELECTRICAL POWER & ENERGY SYSTEMS
Volume 104, Issue -, Pages 269-278Publisher
ELSEVIER SCI LTD
DOI: 10.1016/j.ijepes.2018.07.010
Keywords
Ultra-low frequency oscillation (ULFO); The vector margin (VM) method; Performance limitation; Governor parameter optimization; Nyquist stability criterion; Robust control
Categories
Funding
- National Key R&D Program of China [2016YFB0900605]
Ask authors/readers for more resources
Yunnan Grid, a hydro-dominated system, has experienced many times ultra-low frequency oscillations (ULFO) since the grid is connected to the China Southern Grid via DC ties in 2016. The root cause of the oscillation phenomena is investigated in this work. The vector margin (VM) method, which has a closed-form stability margin expression, is utilized to analyze the phenomena, the analysis reveals that the large phase lags of hydro-power turbines at the oscillation frequency are the culprit. It is proved analytically that a hydro-dominated system model always includes a right-half-plane zero, and this zero introduces the large phase lag afore-mentioned and places a fundamental conflict between the stability and tracking performance. A frequency-domain robust fixed-order controller design method is proposed to maximize the tracking performance with specified stability margin in multiple operating points. Case studies of the four-machine two-area system and Yunnan Grid validate the introduced results.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available