Comparison of three stability analysis methods for delayed cyber-physical power system

• Published in: 2016 China International Conference on Electricity Distribution (CICED) pp. 1 - 5
• Main Authors: Weikang Gao, Hua Ye, Yutian Liu, Liang Wang, Wenbin Ci
• Format: Conference Proceeding
• Language: English
• Published: IEEE 01.08.2016
• Subjects: Asymptotic stability; Delay effects; Delays; eigen-analysis; infinitesimal generator discretization; linear matrix inequality; Numerical stability; Padé approximation; Power system stability; spectral discretization; Stability criteria; time delay
• ISSN: 2161-749X
• DOI: 10.1109/CICED.2016.7576361

The power system with wide-area damping controllers (WADC) embedded is essentially complex delayed cyber-physical power system (DCPPS) since time delays are introduced during transmitting and processing wide-area measurements. In this paper, three methods for stability analysis of DCPPS, i.e., delay-dependent stability criterion in the time domain, Padé approximation-based method as well as explicit infinitesimal generator discretization-based method (EIGD) in the frequency domain are extensively compared from both theoretical and numerical analysis in terms of conservativeness, accuracy, scalability and the capability of handling multiple delays. Simulation results reveals that: (1) The conservativeness in delay margin derived by delay-dependent stability criterion reaches to 7.09% for the two-area four-machine test system. (2) Padé approximation-based eigen-analysis method is sufficiently accurate even a low order of the approximation, e.g., 3 rd order, is used. (3) Padé approximation-based eigen-analysis method is more efficient than EIGD for small stability analysis of large DCPPS.