大扰动下缺额功率分配及频率分布特性研究

Study on Characteristics of Deficient Power Allocation and Frequency Distribution under Large Disturbance

特高压交直流输电工程不断投运,电网功率扰动事件频发。同时越来越多的新能源在电网中取代部分传统机组,导致电力系统的惯量水平下降,对频率支撑能力下降。为此,研究了电网受扰时不平衡功率的分配特性、频率压降的分布特性以及在新能源机组附近产生的连锁反应。根据频率分布的特点提出了区域惯量的概念,并进行仿真分析。结果表明,不平衡功率分配大小与线路阻抗有关,且频率变化率具有分布特性频率响应的分布特性有利于后期新能源并网惯量调频措施的研究。

The UHV AC/DC transmission project has been put into operation continuously,and the power grid power disturbance events occur frequently.At the same time,more and more new energy sources are replacing some traditional units in the power grid,resulting in a decline in the inertia level of the power system and a decline in the ability to support frequency.For this reason,the distribution characteristics of unbalanced power,frequency voltage drop and chain reaction near new energy units were studied when the power grid was disturbed.According to the characteristics of frequency distribution,the concept of regional inertia was proposed and simulated.The results show that the unbalanced power distribution is related to the line impedance and the frequency change rate has the distribution characteristics of the distribution characteristic frequency response,conducive to the research of the new energy grid connection inertia frequency modulation measures in the later stages.