高比例电力电子电力系统频率响应的惯量体系研究

Research on Inertia System of Frequency Response for Power System With High Penetration Electronics

高比例电力电子电力系统中,大规模新能源与直流跨区输电接入替代了原同步电网的部分同步机,系统惯量在特点及形式上发生改变,由此带来的低惯量问题改变了系统频率特性,传统惯量响应体系及分析方法面临挑战。该文从传统同步系统频率响应机理出发,阐述电力电子设备接入对系统频率动态过程的影响。针对高比例电力电子电力系统的复杂惯量响应特性,在充分分析惯量响应阶段影响因素及作用机理基础上,从惯性为抵抗系统频率变化的物理属性出发,对同步发电机惯量的概念进行拓展,提出电力系统广义惯量定义,并从系统层面对不同惯量形式进行梳理并分类,形成系统频率响应的广义惯量响应体系及分析方法。最后,介绍新能源接入对系统惯量进而对系统频率的影响,并对未来电力系统广义惯量水平进行推演,从而为高比例电力电子电力系统频率稳定研究奠定基础。

In the power system with high penetration electronic devices, parts of synchronous machines were replaced by large-scale renewable energy and DC transmission. The system inertia has changed in characteristics and form. The traditional inertia response system and analysis methods are facing challenges. In this paper, the impact of power electronic devices integration on the system frequency dynamic process was described based on the frequency response mechanism of traditional synchronous system. Aiming at the complex inertia response characteristics of power system with high penetration electronics, the concept of synchronous generator inertia was extended and generalized inertia definition of power system was proposed in this paper based on the physical properties of inertia to resist the frequency change of the system. Different forms of inertia were combed and classified from system levels, which formed the generalized inertia response and analysis method for power system of high penetration electronics. Finally, the impact of renewable energy on system frequency was introduced and the generalized inertia level of future system was deduced, which laying the foundation for the frequency stability research of power system with high penetration electronics.