Analysis of Frequency Oscillation Caused by AGC in Hydro-Dominant Power Grids using Piecewise Linearization Method

作者：Yiping Chen, Liang Xiao, Qin Gao, Kehan Zeng, Shengjing She, Rongzhao Yang · 年份：2020 · DOI：10.1109/pesgm41954.2020.9282099 · 被引用次数：4 · 研究领域：Power System Optimization and Stability、Frequency Control in Power Systems、HVDC Systems and Fault Protection

A piecewise linearization model is developed for the analysis of ultra-low frequency oscillation, taking the nonlinearity of governor deadband and the automatic generation control (AGC) into considerations. Firstly, the ultra-low frequency oscillations occurred in actual power grids are discussed in depth. Then, based on the piecewise linearization model developed, the AGC-excited frequency mode is calculated and key factors that influence the frequency stability are analyzed using the eigenvalue approach. Results show that the governor deadband introduces a frequency mode that likely to be excited by large frequency bias coefficient B of the AGC system. To avoid this frequency oscillation, it is advised that B should be properly tuned under the situation when only the secondary frequency regulation is activated.