考虑载波相位的并网逆变器多机并联系统建模与环流产生机理分析  

Modeling of Grid-connected Inverter Multi-machine Parallel System Considering Carrier Phase and Analysis of Loop Current Generation Mechanism

作　　者：郑仙 史明明 喻建瑜 费骏韬 谢文强 ZHENG Xian;SHI Mingming;YU Jianyu;FEI Juntao;XIE Wenqiang(Electric Power Research Institute of State Grid Jiangsu Electric Power Co.,Ltd.,Nanjing 211103,China)

机构地区：[1]国网江苏省电力有限公司电力科学研究院,南京211103

出　　处：《高电压技术》2025年第4期1579-1588,I0005,共11页High Voltage Engineering

基　　金：国网江苏省电力有限公司科技项目(J2022028)。

摘　　要：为了探究分布式发电系统中多台并网逆变器并联运行时由于载波相位异步导致的环流谐振问题,提出了一种考虑载波相位的并网逆变器多机并联系统建模与稳定性分析方法。首先,使用小信号扰动法建立了考虑正弦脉宽调制(sinusoidal pulse width modulation,SPWM)环节边带效应影响的并网逆变器两频率模型,分析了载波相位对并网逆变器多机并联系统中环流的影响。在两频率模型的基础上,使用广义奈奎斯特判据分析了弱电网下并网逆变器多机并联系统环流的稳定性。结果表明:当并网逆变器载波相位不一致时,系统中会存在环流;所提分析方法可以准确分析并网逆变器多机并联系统环流产生机理和稳定性,为分布式发电系统的稳定运行、故障分析与进一步研究打下基础。In order to investigate the circulating current resonance problem caused by carrier phase asynchronization in the multi-machine parallel grid-connected inverters system in a distributed power generation system,a modeling and stability analysis method considering carrier phase for multi-machine parallel grid-connected inverters system is proposed.Firstly,a small-signal perturbation method considering the sideband effect of sinusoidal pulse width modulation(SPWM)is used to establish the two-frequency model of grid-connected inverter.The influence of carrier phase on circulating current in the multi-machine parallel grid-connected inverters system is analyzed.Based on the two-frequency model,the stability of the circulating current in the multi-machine parallel grid-connected inverters system under the weak grid is analyzed by using the generalized Nyquist criterion.The analysis results indicate that,when the carrier phase of the grid-connected inverter is inconsistent,there will be circulating current in the system.The proposed analysis method can be adopted to analyze the generation mechanism and stability of circulating current in the multi-machine parallel grid-connected inverters system accurately,laying a foundation for the stable operation,fault analysis,and further research of distributed power generation system.

关 键 词：并网逆变器 多机并联 弱电网 两频率模型 载波相位 环流 

分 类 号：TM464[电气工程—电器]