基于改进下垂控制的孤岛交流微电网无功分配研究  

REACTIVE POWER DISTRIBUTION CONTROL STRATEGY IN ISLANDED AC MICROGRID BASED ON IMPROVED DROOP CONTROL

作　　者：颜丽 米阳 孙威 蔡杭谊 牛庆松 亓富军 Yan Li;Mi Yang;Sun Wei;Cai Hangyi;Niu Qingsong;Qi Fujun(College of Electrical Engineering,Shanghai University of Electric Power,Shanghai 200090,China;Sunwoda Electronic Co.,Ltd.,Shenzhen 518108,China;State Grid Zhejiang Cixi Power Supply Company,Ningbo 315300,China;State Grid Linyi Power Supply Company,Linyi 276000,China)

机构地区：[1]上海电力大学电气工程学院,上海200090 [2]欣旺达电子股份有限公司,深圳518108 [3]国网浙江慈溪市供电公司,宁波315300 [4]国网临沂供电公司,临沂276000

出　　处：《太阳能学报》2021年第8期7-15,共9页Acta Energiae Solaris Sinica

基　　金：国家重点研发计划(2017YFB0903400);上海市科委项目(18020500700);上海绿色能源并网工程技术研究中心项目(13DZ2251900);“电气工程”上海市Ⅱ类高原学科;上海市电站自动化技术重点实验室项目。

摘　　要：在孤岛运行交流微电网中,受分布式电源(DG)间等效线路阻抗差异的影响,传统下垂控制难以按照下垂增益合理分配无功功率。为此,提出一种基于自适应虚拟阻抗的改进下垂控制方法。即利用DG输出无功信息构造自适应虚拟阻抗,消除等效线路阻抗差异,从而提高无功功率分配精度,并添加电压补偿环节,补偿虚拟阻抗上产生的电压降落。此外,针对频率偏移问题,构造基于DG自身频率与频率参考值差值的积分项作为自频恢复环节以及基于DG输出有功与有功均值差值的积分项作为频率补偿环节。其中,功率均值利用基于局部信息的一致性算法获取,无需全局通信系统控制DG间的信息。最后通过Matlab仿真和RTDS实验设计,验证了所提策略的有效性。In the islanded AC microgrid,due to the unmatched line impedance among distributed generators(DG),reasonable distributing reactive power according to droop gain is difficulty by using the traditional droop control. Therefore,an improved droop control method based on adaptive virtual impedance is proposed. In order to eliminate the unmatched line impedance and improve the sharing accuracy of reactive power of DG units,the virtual impedance is constructed by taking advantage of the output reactive power of DG units. Aiming at the voltage drop caused by virtual impedance,the voltage compensation method is proposed. Additionally,considering the frequency deviation problem,the integral term based on the deviation between the DG’s frequency and frequency reference value is constructed as the self-frequency recovery link,and the integral term based on the deviation between the DG’s output active power and the average active power of system is used as the frequency compensation link to realize the frequency adjustment without deviation. The average power can be obtained by using distributed consistency algorithm with local information. Finally,the effectiveness of the proposed strategy is verified through Matlab simulation and RTDS experimental.

关 键 词：微电网 分布式发电 下垂控制 孤岛 虚拟阻抗 一致性控制 

分 类 号：TM464[电气工程—电器]