基于频率偏移面积的功率缺额计算及低频减载整定  

Power Deficit Calculation and under Frequency Load Shedding Strategy Based on the Frequency Deviation Area

作　　者：刘克天 张钧 李军[1] 陈凡[1] Liu Ketian;Zhang Jun;Li Jun;Chen Fan(School of Electric Power Engineering Nanjing Institute of Technology,Nanjing 211167 China;Grid Development Comprehensive Research Institute State Grid Energy Research Institute Co.Ltd,Beijing 102209 China)

机构地区：[1]南京工程学院电力工程学院,南京211167 [2]国网能源研究院有限公司电网发展综合研究所,北京102209

出　　处：《电工技术学报》2021年第5期1040-1051,共12页Transactions of China Electrotechnical Society

基　　金：南京工程学院引进人才科研启动基金资助项目(YKJ201520)。

摘　　要：针对现有低频减载功率缺额计算不准确、各轮次切负荷量一经整定就固定等缺点,提出一种基于频率偏移面积的功率缺额计算方法和低频减载整定方案。首先,对扰动后同一时刻各母线频率偏移面积与系统惯性中心频率偏移面积近似相等的基本假设进行理论证明;然后,建立惯性中心频率偏移面积与功率缺额之间的关系,低频减载通过测量母线频率偏移面积便可计算功率缺额,设计功率缺额计算程序启动机制,并提出基于缺额大小的低频减载整定方案,低频减载各轮次切负荷量根据功率缺额的大小而改变;最后,分别使用IEEE 39及IEEE 145母线系统对功率缺额计算方法和低频减载方案的有效性进行了验证。算例分析表明:基于频率偏移面积的功率缺额计算方法能够准确计算系统的功率缺额;基于功率缺额大小的低频减载整定方案,在提高系统最低频率及频率恢复速度方面具有一定的优势。Aiming at the power deficit calculation inaccuracy and the fixed amount of load shed by under frequency load shedding(UFLS),a power deficit calculation algorithm and an UFLS strategy based on frequency deviation area are proposed in this paper.The assumption that the frequency deviation areas of every bus are equal to the system center of inertia(COI)frequency deviation area at the same time is theoretically proved.Then,the relationship between the COI frequency deviation area and the system power deficit is derived.The UFLS can calculate the system power deficit only using the local frequency deviation area measured.The startup mechanism of the UFLS power deficit calculation program is designed and different UFLS schemes are proposed.Finally,the power deficit calculation algorithm and UFLS strategy are tested in the IEEE 39 and IEEE 145 bus system.The case studies show that the algorithm in this paper can calculate the power deficit accurately and the UFLS strategy can raise the minimum frequency of the system and accelerate the frequency recovery.

关 键 词：功率缺额计算 低频减载整定策略 频率偏移面积 母线频率 惯性中心频率 

分 类 号：TM761[电气工程—电力系统及自动化]