中国电机工程学报2017，Vol.37Issue(5)：1277-1292,16.DOI:10.13334/j.0258-8013.pcsee.162538
三相变流器并网系统的广义阻抗及稳定判据
Generalized-impedance and Stability Criterion for Grid-connected Converters
摘要
Abstract
The output impedance matrix of grid-connected converter plays an important role in system stability.Due to the dynamics of power grid or phase locked loop (PLL),the output impedance matrices of the converter and grid are difficult to be decoupled simultaneously either in dq domain or in phase domain.This has become a difficulty for system oscillation analysis via impedance-based stability criterion (ISC).To this end,the generalized-impedance-based stability criterion (gISC) was proposed to handle the coupling terms and simplify the system stability analysis under some sufficient conditions.Firstly,the impedances of the converter and the grid in polar coordinates were formulated,and the concept of generalized-impedance of the converter and the grid was put forward.Secondly,by strict mathematical derivation,the critical equation,which implies the dynamic interaction between the converter and the grid,was extracted from the characteristic equation of the grid-connected converter system.It is shown that the small-signal instability of the system can be explained as the resonance of the generalized-impedances of the converter and the grid.Moreover,the gISC can be regarded as the extension of ISC,and the gISC is equivalent to ISC when the focused frequency is out of the bandwidth of outer-loop control and PLL.Finally,digital simulation and hardware-in-the-loop (HIL) simulation based on the RT-LAB were carried out to verify the effectiveness of the proposed method.关键词
三相变流器/并网变流器/振荡/小干扰稳定/广义阻抗/阻抗分析法Key words
three-phase converter/grid-connected converters/oscillation/small-signal stability/generalized-impedance/impedance analysis method分类
信息技术与安全科学引用本文复制引用
辛焕海,李子恒,董炜,章雷其,黄伟,邢玉辉,王康..三相变流器并网系统的广义阻抗及稳定判据[J].中国电机工程学报,2017,37(5):1277-1292,16.基金项目
国家重点研发计划项目(2016YFB0900104) （2016YFB0900104）
国家自然科学基金项目(51577168) （51577168）
云南电网科技项目(yndw (2016)000303DD00124).Supported by the National Key Research and development Program of China (2016YFB0900104) （yndw (2016）
National Natural Science Foundation of China (51577168) （51577168）
Science & Technology Project of Yunnan Electric Power Company (yndw (2016) 000303DD00124). （yndw (2016）
