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Volume 13 | Issue 5 | Year 2026 | Article Id. IJEEE-V13I5P101 | DOI : https://doi.org/10.14445/23488379/IJEEE-V13I5P101

Design of Reduced-Order Observer-Based Optimal Controller for SMIB System to Enhance Dynamic Stability

K Himaja, Venkatampalli Maheswari , Sapvath Vinod Kumar

Received Revised Accepted Published
04 Feb 2026 03 Apr 2026 02 Apr 2026 30 May 2026

Citation :

K Himaja, Venkatampalli Maheswari , Sapvath Vinod Kumar, "Design of Reduced-Order Observer-Based Optimal Controller for SMIB System to Enhance Dynamic Stability," International Journal of Electrical and Electronics Engineering, vol. 13, no. 5, pp. 1-10, 2026. Crossref, https://doi.org/10.14445/23488379/IJEEE-V13I5P101

Abstract

This paper introduces a Reduced-Order Observer–Based Optimal Controller (ROOBC) strategy integrated for a Thyristor-Controlled Series Compensator (TCSC) to effectively enhance the dynamic stability of a unique system. The proposed control scheme employs an ROOBC to estimate the unmeasured system states, like rotor angle, thereby lowering computational complexity while maintaining effective control performance. An Optimal State-Feedback Control (OSFC) law is designed based on the estimated states to improve the system dynamic response under disturbance. The effectiveness of the proposed ROOBC-based TCSC controller is checked on a unique system and compared with conventional TCSC control, Power System Stabilizer (PSS), and the system without control. Stability assessment is carried out through eigenvalue analysis and time-domain simulations at the nominal operating condition. The results demonstrate that the proposed ROOBC-based TCSC significantly enhances dynamic stability and provides superior dynamic performance compared to the other control strategies considered.

Keywords

Damping Ratio, Dynamic Stability, Eigenvalues, PSS, ROOBC, TCSC.

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