Analysis of power system frequency oscillations with intentional governor deadbands using describing functions. (October 2019)

• Record Type: Journal Article
• Authors: Chen, Lei; Lu, Zongxiang; Min, Yong; Yu, Rui; Liu, Baisi; Chen, Qun
• Is Part Of: International journal of electrical power & energy systems. Volume 111(2019)
• Page Start: 390
• Page End: 397
• Publication Date: 2019-10
• Subjects: Damping torque -- Describing function -- Frequency oscillation -- Governor deadband -- Periodic solution; Electrical engineering -- Periodicals; Electric power systems -- Periodicals; Électrotechnique -- Périodiques; Réseaux électriques (Énergie) -- Périodiques; Electric power systems; Electrical engineering; Periodicals; 621.3
• DOI: 10.1016/j.ijepes.2019.04.021
• Languages: English
• ISSNs: 0142-0615

Abstract

Highlights: A method is proposed to analyze frequency oscillations with governor deadbands. Stability criteria based on eigenvalue locus with frequency amplitudes are given. Effect of a deadband on frequency oscillations is analyzed using damping torque. Abstract: Frequency oscillations are observed in several power systems. Governor deadband introduces nonlinearity to the system and affects frequency oscillations. A method using describing functions is proposed to analyze frequency oscillations with multiple intentional governor deadbands, including nonstep and step implementations. The deadbands are represented as gains of their describing functions dependent on frequency amplitudes, and the locus of eigenvalues with frequency amplitudes is computed to study the behavior of frequency oscillations. The stability criteria based on the eigenvalue locus are given. The relative location of the locus of damping ratios to the horizontal axis determines the behavior of frequency oscillation. The effect of a deadband on frequency oscillations is analyzed using the damping torque. Whether a deadband is beneficial or detrimental to frequency oscillations is affected by the damping torque of the prime mover. Time-domain simulation results validate the proposed methods and conclusions.