摘要
提出一种基于虚拟同步发电机运行的逆变器并联控制方法,在与传统下垂控制方法相比较基础上,具体分析了该方法在等效输出阻抗与无功功率输出的解耦和提升负荷功率分配精度方面的优势和原理,同时对下垂控制器进行小的修正,减小并联运行逆变器空载运行电压和频率差值,以使其满足不同额定功率逆变器并联功率分配和空载环流抑制的需求,并添加微分环节补偿功率计算带来的控制滞后。设计两台容量比为2∶1的逆变器互联仿真和实验,在模式切换和负载突变情况下可实现快速跟踪功率变化和环流抑制,并能按照单位容量均分负荷。
The new method of operating an inverter to imitate a synchronous generator for circulating current restraint is motivated and developed.Based on the comparison with the traditional droop control method,detail analysis is done on the principles of decoupling between the equivalent line impedance and output reactive power and the advantage of the new method to improving the accuracy of the load power distribution is described.In order to reduce voltage and frequency difference between the paralleled inverters when no-load operating,minor amendment is used to the droop control coefficient to meet the demand of load power distribution between different rated power inverters and circulation suppression and adding differential link to improve the control delays caused by power calculation.Simulation and experiment are done in a small-scale experimental micro-grid system which contains two inverters in parallel.The results are given to verify that the circulation inhibitory is effective in a variety of conditions.
出处
《电工技术学报》
EI
CSCD
北大核心
2012年第1期40-47,共8页
Transactions of China Electrotechnical Society
基金
国家重点基础研究发展计划(973计划项目)(2009CB219706)
中国与欧洲政府间国际合作计划项目(2010DFA61640)
湖南省研究生科研创新项目(CX2011B130)
国家自然科学青年基金(50907019)资助
关键词
分布式发电
同步发电机
逆变器
微网
环流
Distributed generation
synchronous generator
inverter
micro-grid
circulation
