电压型与电流型逆变器序阻抗建模与分析  

Sequence Impedance Modeling and Analysis of Voltage Controlled and Current Controlled Inverters

作　　者：卫楚奇 石磊[1] 周百灵[1] 李伟祚 WEI Chu-qi;SHI Lei;ZHOU Bai-ling;LI Wei-zuo(State Grid Electric Power Research Institute,Jiangsu 211106,China)

机构地区：[1]国网电力科学研究院,江苏南京211106

出　　处：《电力电子技术》2020年第10期107-110,共4页Power Electronics

摘　　要：并网逆变器作为分布式发电与电网的主要接口装置,按照控制方法的不同可以分为电压控制型和电流控制型。在此采用谐波线性化的方法分别建立电压控制型和电流控制型逆变器的小信号序阻抗模型,对比分析两种类型的序阻抗特性。电流控制型的序阻抗在中频段呈负阻抗特性,阻抗幅值很小;电压控制型的序阻抗在中频段呈感性,与电网的阻抗特性相似。电流控制型逆变器接入弱电网容易发生谐波振荡,电压控制型对弱电网有较强的适应性且在高渗透率新能源发电下依旧可以稳定运行。最后通过实验验证了分析的正确性。As the main interface device between distributed generation and power grid,grid connected inverter can be divided into voltage control type and current control type according to different control methods.The harmonic linearization method is used to establish the small signal sequence impedance models of voltage controlled and current controlled inverters respectively,and the two types of sequence impedance characteristics are compared and analyzed.The sequence impedance of current control type is negative in the middle frequency band,and the impedance amplitude is very small.The sequence impedance of voltage control type is inductive in the middle frequency band,which is similar to the impedance characteristics of power grid.The current controlled inverter is easy to produce harmonic oscillation when connected to the weak power grid.The voltage controlled inverter has strong adaptability to the weak power grid and can still operate stably under the high permeability new energy generation.Finally,the correctness of the analysis is verified by experiments.

关 键 词：逆变器 序阻抗建模 弱电网 

分 类 号：TM464[电气工程—电器]