摘要
电网异步互联后送端系统频率稳定性差,直流频率限制控制器(Frequency Limit Controller, FLC)能够根据频率偏差迅速调节直流功率,稳定送端系统频率。文中基于传统FLC提出了一种改进的自适应直流频率限制器(Adaptive Frequency Limit Controller, AFLC)和利用AFLC参与电网二次调频的协同控制策略。通过对传统FLC作用机理分析和功率转带场景分类,并计及FLC不同控制策略对系统功率转带和频率调控的影响规律,设计了一种自适应直流频率限制器AFLC,在提高系统调频精度的同时可以迅速调控系统发生严重故障时出现的频率偏差。同时依据有功功率分配原则和二次调频的原理,让AFLC参与二次调频并承担部分有功功率。在Matlab/Simulink软件中搭建了云南电网楚穗双回直流输电系统仿真模型对所提策略进行仿真分析,仿真结果表明,所提AFLC控制策略更有效地实现了系统受小扰动后的频率调控和严重故障后功率的转带、AFLC与二次调频配合的策略提高了系统二次调频的恢复速度。
The frequency stability of sending end system is poor after the power grid is asynchronously interconnected.The frequency limit controller can quickly adjust the DC power and stabilize the frequency of the sending system according to the frequency deviation.Based on traditional FLC,this paper proposes an improved adaptive frequency limit controller and a cooperative control strategy using AFLC to participate in the secondary frequency regulation of power grid.By analyzing the action mechanism of traditional FLC,classifying the power transfer scenarios,and considering the influence of different FLC control strategies on system power transfer and frequency regulation,this paper designsan adaptive frequency limit controller which can not only improve the frequency modulation accuracy of the system,but also quickly regulate the frequency deviation in case of serious system failures.Meanwhile,AFLC is designed to participate in secondary frequency modulation and undertake part of the active power according to the principle of active power distribution and the principle of secondary frequency modulation.The simulation model of Chusui actual double circuit DC transmission system of Yunnan power grid is built in Matlab/Simulink software to verify the effectiveness of the proposed strategy.The simulation result shows that the AFLC can more effectively achieve the frequency regulation of the system after small disturbance and the power transfer after serious system failure.The strategy of combining AFLC with secondary frequency modulation can improve the recovery speed of secondary frequency modulation.
作者
辛业春
于浩浩
XIN Yechun;YU Haohao(Key Laboratory of Modern Power System Simulation and Control&Renewable Energy Technology,Ministry of Education(Northeast Electric Power University),Jilin Jilin 132012)
出处
《东北电力大学学报》
2023年第2期55-62,共8页
Journal of Northeast Electric Power University
基金
吉林省科技发展计划项目(20210509059RQ)。
关键词
异步互联
调频策略
直流功率
直流频率限制器
Asynchronous interconnection
Frequency modulation strategies
DC power
Frequency limit control
