Grid-connected Inverter Stabilization Method Based on Adaptive Composite Admittance Correction

被引：0
|
作者：
Du Y. [1 ,2 ]
Zhang M. [1 ,2 ]
Yang X. [1 ,2 ]
Yan M. [1 ,2 ]
Sun Q. [1 ,2 ]
Su J. [1 ,2 ]
机构：
[1] School of Electrical and Automation Engineering, Hefei University of Technology, Hefei
[2] Research Center for Photovoltaic Systems Engineering of Ministry of Education, Hefei University of Technology, Hefei
来源：
Gaodianya Jishu/High Voltage Engineering | 2022年 / 48卷 / 06期
关键词：
grid voltage feedforward; grid-connected inverter; impedance reshaping; phase-locked loop; self-adaption; stability; weak grid;
D O I：
10.13336/j.1003-6520.hve.20210215
中图分类号：
学科分类号：
摘要：
Under weak grid conditions, the grid-connected inverter system with phase-locked loop and grid voltage feedforward is coupled with the grid impedance to cause the system instable. Reshaping the system impedance can effectively solve the stability problem caused by the phase-locked loop or the grid voltage feedforward, therefore, a compound admittance correction strategy is proposed. Based on the principle of equivalent transformation, the system admittance is divided, and the negative effects of phase-locked loop and grid voltage feedforward on the system admittance are analyzed.Beginning with transforming the phase-locked loop, we proposed a phase-locked loop structure with a band-pass filter, and designed the damping coefficient of the band-pass filter with power factor and the system stability margin as constraints.In accordance with the phase-up limitation of the band-pass filter, an adaptive grid voltage control method including proportional and differential feedforward is proposed, and the grid voltage feedforward term coefficient is adaptively adjusted with the phase margin under different grid admittance conditions as the target. Finally, the experimental verification is carried out on StarSim experimental platform. The research results show that the adaptive composite admittance correction strategy broadens the system’s adaptability to the grid admittance, making the system stable even in extremely weak grids. © 2022 Authors. All rights reserved.
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页码：2088 / 2097
页数：9
相关论文
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