摘要
基于输出阻抗的稳定性分析方法作为常见的谐振稳定性分析方法,在逆变器集群系统稳定性研究中得到了广泛的应用。由于下垂控制逆变器的控制环路复杂,因而难以综合下垂控制环,建立下垂控制逆变器精确的输出阻抗模型。该文首先将采用小信号建模方法,获得基于下垂控制的输出阻抗模型,并详细分析下垂控制逆变器输出阻抗模型对下垂控制系数扰动的敏感程度,揭示下垂控制系数,尤其是Q-U控制系数,主要影响逆变器较低频率输出阻抗外特性。然后,分析输出阻抗模型对逆变器双闭环参数扰动的敏感性影响,揭示下垂控制逆变器输出阻抗的高频输出阻抗主要由电压外环控制器参数及LC滤波器的电容容值主导。构造基于以上三参数的输出阻抗简化模型,进一步佐证了该结论。最后,测量逆变器输出阻抗,验证模型及研究方法的正确性。
The impedance-based specification is normally used to analyze the stability of multiple inverter system in the state-of-the-arts. However, it is difficult to establish an accuracy output impedance model of droop controlled inverter with the droop control loop, since the control loop is complicated. In this paper, the output impedance of droop controlled inverter was obtained by small-signal method, and parameters of droop control were analyzed based on the derived impedance. It disclosed that the droop control mainly affects the lower-frequency impedance profiles which was determined by Q-U control coefficient. Then, the impacts of dual-loop parameters were also analyzed, it was found that the higher-frequency impedance is sensitivity to voltage closedloop control parameters and capacitance value of LC filter. And a simplified output impedance based on three parameters was built for further verification. Finally, impedance measurement was carried out to verify the validity of the output impedance model, and analyzing method.
作者
冯夏云
汪飞
李玉菲
张笠君
任林涛
FENG Xiayun;WANG Fei;LI Yufei;ZHANG Lijun;REN Lintao(Shanghai Key Lab of Power Station Automation Technology(Shanghai University),Baoshan District,Shanghai 200444,China)
出处
《中国电机工程学报》
EI
CSCD
北大核心
2020年第21期7012-7021,共10页
Proceedings of the CSEE
基金
国家自然科学基金(面上基金项目)(51577113)
国家重点研发计划项目(2017YFE011240)。
关键词
下垂控制逆变器
输出阻抗外特性
参数敏感性分析
主导参数
阻抗测量
droop controlled inverter
output impedance profiles
parameters sensitive analysis
dominant parameters
impedance measurement
