期刊论文

Frequency Division Compensation Method for Phase Margin of Grid Connected Converters in the Weak Grid

中文

中国电机工程学报

0258-8013

2024

44

4

1565-1575,中插26

10.13334/j.0258-8013.pcsee.223001

本校为第一机构

在弱电网条件下,针对并网变流器各控制环节与电网阻抗之间交互作用,容易引发系统振荡而造成失稳问题,文中提出一种分频段相位补偿控制策略.首先,建立 dq 坐标下的并网变流器输出导纳矩阵模型,针对在低频段由锁相环引起的变流器输出导纳的负阻尼特性,不改变锁相环动态特性而通过分析锁相环对控制系统的影响路径,加入含积分元素的补偿矩阵抵消锁相环的负阻尼影响,同时简化导纳模型;进而,引入仅含常数元素的补偿矩阵实现超前校正,对电流环带宽外的负阻尼进行相位补偿,使导纳矩阵元素在全频段为正实部,为并网控制系统提供正阻尼,从而增强并网变流器的稳定性.最后,通过仿真和实验在不同短路比条件下对...

Under the condition of weak grid,aiming at the interaction between the control links of grid connected converter and the grid impedance,which is easy to cause system oscillation and instability,this paper proposes a frequency division phase compensation control strategy.First,the output admittance matrix model of grid connected converter in dq coordinate is established.In view of the negative damping characteristics of the output admittance of the converter caused by the phase-locked loop(PLL)in the low frequency band,the influence path of the PLL on the control system is analyzed without chan...