计及频率波动的新能源机组脱网概率预测  

Off-grid Probability Prediction of New Energy Units Considering Frequency Fluctuations

作　　者：张嘉怡 任惠[1] 王希 王威 ZHANG Jiayi;REN Hui;WANG Xi;WANG Wei(Department of Electrical Engineering,North China Electric Power University,Baoding 071003,China;Marketing Service Center,State grid Hebei Electric Power Co.,Ltd.,Shijiazhuang 050000,China;Baoding Power Supply Branch,State grid Hebei Province Electric power Co.,Ltd.,Baoding 071051,China)

机构地区：[1]华北电力大学电力工程系,河北保定071003 [2]国网河北省电力有限公司营销服务中心,河北石家庄050000 [3]国网河北省电力有限公司保定供电分公司,河北保定071051

出　　处：《电力科学与工程》2024年第12期23-32,共10页Electric Power Science and Engineering

基　　金：国家自然科学基金资助项目(51107040)。

摘　　要：近年来,多次大停电事故分析结果显示,在故障发展过程中,频率涉网保护动作会使新能源机组脱网,加剧系统状态恶化。高占比新能源电力系统惯量相对减小。当功率扰动出现时,系统的频率响应轨迹呈现偏差增大和变化率增高的特征。这种响应可能会触发发电机组的涉网保护,进而导致低频减载动作,使故障扩大。基于此,在考虑系统频率波动的基础上,对发电机的可靠性模型进行研究。采用可靠性理论中的应力强度干涉模型建立了新能源机组脱网概率的计算模型,实现了对新能源机组脱网概率的实时评价。用系统事故后3种算例中所提取的系统频率数据进行验证。结果表明所提出方法可以用于对新能源机组脱网导致电力系统发生连锁故障概率进行实时评价。In recent years,the analysis results of multiple blackouts show that the frequency network-related protection action will cause the new energy units to off-grid and aggravate the deterioration of the system status in the process of fault development.The inertia of new energy power system with the high proportion is relatively.When the power disturbance occurs,the frequency response trajectory of the system shows the characteristics of increasing deviation and increasing rate of change.This response may trigger the grid-related protection of generating units,which in turn leads to low-frequency load shedding actions and expands the fault.Based on this,the reliability model of the generator is studied on the basis of considering the frequency fluctuation of the system.The stress intensity interference model in reliability theory is used to establish a calculation model for the off-grid probability of new energy units,and the real-time evaluation of the off-grid probability of new energy units is realized.Validation is performed using the system frequency data extracted from the three examples after a system accident.The results show that the proposed method can be used for real-time evaluation the probability of cascading failures in the power system due to the off-grid of new energy units.

关 键 词：连锁故障 新能源机组脱网 频率预测 可靠性分析 系统惯量 

分 类 号：TM712[电气工程—电力系统及自动化]