高比例电力电子电力系统过电压(一):定义、分类及相关要求

Overvoltage of the Power System Integrated With High Proportion of Power Electronics(I):Definition,Classification and Relevant Requirements

随着新能源发电设备的大量投运和大容量交直流输电工程的相继投产,我国已初步形成高比例电力电子电力系统的基本格局,以过电压为代表的安全问题日渐凸显。然而,高比例电力电子电力系统过电压起因众多、产生机理繁复,对新能源外送及直流输电能力构成了严重制约。为解决上述问题,该文从大电网安全稳定视角出发,首先明确电力系统过电压的基本概念及其分类,分析高比例电力电子电力系统中不同过电压的起因与波形特征。进一步围绕3个实际电网过电压问题较为突出的场景,分析不同场景下过电压产生的原因、各类设备的过电压耐受能力及限制因素,论述传统交流设备过电压及新型电力电子设备在过电压场景中可能存在的安全风险。最后,总结了高比例电力电子电力系统过电压的分析流程,并结合时域仿真算例进行论述说明。

With the integration of large scale of renewable energy plants and large capacity AC/DC transmission projects,the power system integrated with high proportion of power electronics has been formed,and the security and stability problems represented by power system overvoltage have become increasingly prominent.However,the causes and mechanisms of overvoltage are relatively complex,which restricts the capability of renewable energy generation and HVDC transmission.Based on the above considerations,this paper introduces the definition,classification,and characteristics of power system overvoltage.Further,focusing on three scenarios of the actual power grid where the overvoltage problem is more prominent,the causes of overvoltage,the voltage capability constraints of various types of equipment and their limiting factors are analyzed.Then,possible security risks of traditional AC equipment and power electronic equipment under different scenarios are illustrated.At the end of this study,the overvoltage analysis process is summarized,and its applicability is demonstrated through a time-domain simulation example.