Markovian switching model and non‐linear DC modulation control of AC/DC power system. Issue 10 (28th June 2017)

• Record Type: Journal Article
• Authors: Liu, Ziwen; Miao, Shihong; Fan, Zhihua; Han, Ji
• Is Part Of: IET generation, transmission & distribution. Volume 11:Issue 10(2017)
• Page Start: 2654
• Page End: 2663
• Publication Date: 2017-06-28
• Subjects: AC‐DC power convertors -- power system control -- Markov processes -- delays -- robust control -- power system transient stability -- nonlinear control systems; Markovian switching model -- nonlinear DC modulation control -- AC‐DC power system -- continuous‐discrete hybrid system -- random discrete events -- continuous time discrete events -- time‐delay compensation -- Markovian state transition -- robust compensation control -- dual‐infeed AC‐DC system -- transient stability; Electric power production -- Periodicals; Electric power transmission -- Periodicals; Electric power distribution -- Periodicals; 621.3105
• DOI: 10.1049/iet-gtd.2016.1862
• Languages: English
• ISSNs: 1751-8687

Abstract

Abstract : Since the power system is actually a continuous‐discrete hybrid system jointly driven by continuous time and random discrete events, a Markovian switching model of AC/DC power system is established to reflect the operating state of the system. Based on the model, a novel non‐linear DC modulation control with time‐delay compensation is derived to improve the transient rotor‐angle stability of the entire AC/DC power system. The main contributions are: (i) the external events are described as Markovian jumps in system model parameters to reflect the random discrete characteristic of system operating. Meanwhile, the Markovian state transition rates are replaced by the outage rates and repair rates, which avoids expensive computation when the numbers of system operating modes are large; (ii) The time delays are regarded as a kind of bounded disturbance depending on system state and input. By a robust compensation control, the negative influence of time delay disturbance can be eliminated. Simulation performed on a dual‐infeed AC/DC system shows the effectiveness of the proposed method in improving the transient stability of the power system.