Load frequency control scheme design considering flexible disturbances

• Published in: IET renewable power generation Vol. 14; no. 19; pp. 4142 - 4149
• Main Authors: Chen, Chunyu, Zhang, Kaifeng, Ding, Zhetong, Dong, Wenjie, Li, Xiaoqiang, Liang, Rui
• Format: Journal Article
• Language: English
• Published: The Institution of Engineering and Technology 28.12.2020
• Subjects: active disturbance rejection scheme; area control error; compensation; control system synthesis; disturbance estimation; flexible disturbances; flexible RES suppression; frequency control; frequency stability; good power quality; highly flexible renewable energy sources; highly time‐varying disturbances; large‐scale integration; load frequency control scheme design; load regulation; nonlinear control systems; observers; PI control; power generation control; power imbalance; power system control; power system interconnection; power systems; previous ADR‐based LFC schemes; renewable energy sources; Research Article; RES‐generated disturbances; short time scale; sliding mode control scheme; solar energy; variable structure systems; volatility; active disturbance rejection scheme; large-scale integration; solar energy; power generation control; volatility; disturbance estimation; power system interconnection; good power quality; highly time-varying disturbances; previous ADR-based LFC schemes; area control error; load regulation; PI control; frequency stability; renewable energy sources; control system synthesis; frequency control; RES-generated disturbances; flexible RES suppression; short time scale; flexible disturbances; nonlinear control systems; power systems; compensation; power system control; highly flexible renewable energy sources; power imbalance; variable structure systems; observers; sliding mode control scheme; load frequency control scheme design
• ISSN: 1752-1416; 1752-1424
• DOI: 10.1049/iet-rpg.2019.1289

Good power quality cannot be achieved without the frequency stability of power systems. Nevertheless, with the large-scale integration of highly flexible renewable energy sources (RESs) such as wind and solar energy, frequency stability is threatened by RES-generated disturbances due to their volatility and intermittency especially in the very short time scale. Therefore, a new frequency control scheme should be designed to attenuate these highly time-varying disturbances. In this study, load frequency control (LFC) considering flexible RES suppression is investigated. Inspired by the idea of disturbance estimation and compensation, a novel active disturbance rejection (ADR) scheme is proposed. Unlike previous ADR-based LFC schemes, the proposed one can significantly reduce estimation errors via a novel extended state observer. Then a sliding mode control scheme is used to force the area control error to slide along the equilibrium, thus significantly attenuating the power imbalance. Simulation results show the effectiveness of the proposed schemes.