基于PR控制和滤波电感电流的微网限流新方法  

MICROGRID CURRENT-LIMITING METHOD BASED ON PR CONTROLAND FILTER INDUCTANCE CURRENT

作　　者：程启明 沈磊 程尹曼 魏霖[1] 王玉娇 Cheng Qiming;Shen Lei;Cheng Yinman;Wei Lin;Wang Yujiao(Shanghai Key Laboratory Power Station Automation Technology Laboratory(College of Automation Engineering,Shanghai University of Electric Power),Shanghai 200090,China;North Power Supply Branch,Shanghai Electric Power Company,Shanghai 200041,China;College of Electronics and Information Engineering,Tongji University,Shanghai 201804,China)

机构地区：[1]上海市电站自动化技术重点实验室(上海电力大学自动化工程学院),上海200090 [2]上海电力公司市北供电分公司,上海200041 [3]同济大学电子与信息工程学院,上海201804

出　　处：《太阳能学报》2021年第7期35-43,共9页Acta Energiae Solaris Sinica

基　　金：国家自然科学基金(61905139);上海市电站自动化技术重点实验室资助项目(13DZ2273800)。

摘　　要：针对传统的限流方法不能适应不同类型的短路故障问题,提出基于比例谐振(PR)控制和滤波电感电流的微网限流的新方法。首先,把微网中分布式发电(DG)变换器作为研究对象,DG变换器的电压电流双环均采用PR控制器;然后,详细推出滤波电感电流的参考值与DG变换器输出的电流和电压之间关系,该关系表明通过调整控制系统参数和滤波电容,DG变换器输出电流可跟随滤波电感电流的参考值;其次,当DG变换器输出的某相电流大于阈值(即发生故障)时,通过改变滤波电感电流的参考值能实现限制故障电流;最后,软件仿真结果验证新型限流方法能够限制故障电流到额定电流约2倍,且与不同的故障电阻、故障类型和故障发生时间无关;新型限流方法中采用的PR控制相比于PI控制,DG变换器输出的电流峰值更小、响应速度更快。Aiming at the problem that traditional current-limiting methods can not adapt to different types of short-circuit faults,a new current-limiting method based on proportional resonance(PR)control and filter inductance current is proposed.Firstly,the distributed generation(DG)converter in the microgrid is taken as the research object,and the PR controller is used in both voltage and current loops of the DG converter.Secondly,the relationship between the reference value of the filter inductor current and the output current and voltage of the DG converter is derived in detail,the relationship shows that the output current of the DG converter can follow the filter inductor current by adjusting the parameters of the control system and the filter capacitor.Then,the fault current can be limited by changing the reference value of the filter inductor current when the output phase current of the DG converter is larger than the threshold value(i.e.when the fault occurs).Finally,the simulation results show that the new current limiting method can limit the fault current to about twice the rated current,and has nothing to do with the different fault resistances,fault type and fault occurrence time.Compared with PI control,PR control adopted in the new current limiting method has smaller current peak value and faster response speed.

关 键 词：微网 短路故障 比例谐振控制 电流限制方法 滤波电感电流 

分 类 号：TM721[电气工程—电力系统及自动化]