Real-time optimisation of emergency demand response and HVDC power modulation to improve short-term frequency stability of the receiving-end power systems

The Journal of Engineering

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[1] Department of Electrical Engineering, State Key Laboratory of Power Systems, Tsinghua University, Beijing 100084, People's Republic of China;Electric Power Research Institute of State Grid JiBei Electric Power Co., Ltd., Beijing 100045, People's Republic of China;

关键词: HVDC power convertors;    power transmission control;    HVDC power transmission;    power system security;    power system interconnection;    load regulation;    frequency control;    power system stability;    power grids;    frequency stability;    optimisation;    power system control;    frequency response;    HVDC power modulation;    short-term frequency stability;    receiving-end power systems;    varying operation conditions;    frequency instability;    real-time coordinated control strategy;    online-updated frequency response model;    multiple control resources;    emergency demand response;    real-time optimisation;    emergency controls;    short-term frequency dynamics;    existing control strategy;    frequency drops;    emergency frequency control strategy;   

DOI  :  10.1049/joe.2018.8682

来源: publisher

【 摘 要 】

In recent years, large-capacity high-voltage direct currents (HVDCs) have been employed to transfer electricity from the west to the east of China. However, the frequent frequency drops due to HVDC blockings seriously threaten the short-term frequency stability of receiving-end power systems. The existing emergency frequency control strategy is not adaptive to the varying operation conditions and may cause excessive or deficient actions, which could result in inefficient control or high risk of frequency instability. Therefore, a real-time coordinated control strategy is proposed in this study based on the online-updated frequency response model. The model is designed to incorporate multiple types of generators and to reflect the dynamic frequency response of loads. The new control strategy combines multiple control resources, including the emergency demand response and HVDC power modulation, to improve the short-term frequency stability after HVDC failures. By online data preparation and cubic fitting, the nadir of the frequency is expressed as an analytic function of the control variables. A real-time optimisation of emergency controls is achieved to improve the short-term frequency dynamics. Case studies show that the proposed scheme is robust to the varying operation conditions and has lower control cost than the existing control strategy.

【 授权许可】

CC BY