摘要
异步互联系统调频资源和备用容量的分割使得频率稳定问题突出,利用高压直流输电系统的附加频率控制(AFC)可以实现异步互联系统调频备用共享,参与系统频率调控。文中以改善异步互联系统整体的调频性能和频率质量为目标,研究基于直流两侧电网频率差进行无差控制实现异步互联系统准同步运行的直流AFC对两侧电网频率稳定性的影响。利用换流站交直流系统的功率平衡关系建立较为精确的高压直流输电系统线性化模型,得到异步互联两区域系统的负荷频率控制模型,以此进行特征分析指导AFC参数设计。多场景仿真结果表明,准同步运行的直流AFC在使两侧电网趋于同频运行的同时,能够适应两侧电网的容量自动调节直流功率,有效改善全系统的频率稳定特性。
Frequency stability problem of asynchronous interconnected systems is prominent with the division of frequency regulation resources and reserve capacities.The auxiliary frequency control(AFC)of high-voltage direct current(HVDC)transmission system can realize the sharing of frequency regulation reserves of asynchronous interconnected systems and participate in system frequency regulation.In this paper,with the objectives of improving the overall frequency regulation performance and frequency quality of asynchronous interconnected systems,based on the astatic control of frequency difference between HVDC interconnected AC grids on both sides,the influence of HVDC AFC for pseudo-synchronous operation of asynchronous interconnected systems on the frequency stability of AC grids on both sides is studied.A relatively accurate linearized HVDC model is developed using the power equilibrium relationship of AC-DC systems in converter stations,and the load frequency control model of asynchronous interconnected two-area system is obtained,which is used for eigen-analysis to guide the AFC parameter design.Multi-scenario simulation results indicate that the HVDC AFC for pseudo-synchronous operation can automatically adjust the transmission power of HVDC to the capacity of AC grids on both sides while making AC grids on both sides operate at the same frequency,and effectively improve the frequency stability characteristics of the whole system.
作者
皮杰明
张坤
陈亦平
李崇涛
PI Jieming;ZHANG Kun;CHEN Yiping;LI Chongtao(School of Electrical Engineering,Xi’an Jiaotong University,Xi’an 710049,China;Dispatch and Control Center of China Southern Power Grid,Guangzhou 510663,China)
出处
《电力系统自动化》
EI
CSCD
北大核心
2023年第14期82-92,共11页
Automation of Electric Power Systems
基金
国家重点研发计划资助项目(2022YFB2403500)。
关键词
异步互联系统
准同步运行
高压直流输电系统
附加频率控制
线性化模型
频率稳定性
asynchronous interconnected system
pseudo-synchronous operation
high-voltage direct current(HVDC)transmission system
auxiliary frequency control
linearized model
frequency stability
