基于改进非线性下垂控制的微电网并/离网切换技术研究  

Study of micro-grid parallel/off network switching technique based on improved nonlinear droop control

作　　者：王树东[1] 杜巍[1] 王焕宇 林莉 陈维铅 Wang Shudong;Du Wei;Wang Huanyu;Lin Li;Chen Weiqian(College of Electrical and Information Engineering,Lanzhou University of Technology,Lanzhou 730050,China;Gansu Key Laboratory of Solar Power Systems Engineering,Jiuquan New Energy Research Institute,Jiuquan 735000,Gansu,China)

机构地区：[1]兰州理工大学电气工程与信息工程学院,兰州730050 [2]甘肃省太阳能发电系统工程重点实验室酒泉市新能源研究院,甘肃酒泉735000

出　　处：《电测与仪表》2018年第16期112-118,共7页Electrical Measurement & Instrumentation

基　　金：国家自然科学基金项目(51047010);高等学校科研项目(2015A-211);2017年酒泉市科技支撑计划项目

摘　　要：双模式并/离网切换过程中由于控制指令突变产生电压、电流畸变现象,对电网造成不良影响。而传统的下垂控制虽然避免了双模式出现的问题,但它是一种有差调节,也会产生一定的功率波动,影响电网的稳定。因此本文在分析上述问题的基础上提出一种改进的并/离网下垂单模式切换控制策略,即在切换前对逆变器输出电压幅值、频率和功率进行预同步,在切换过程中利用改进的非线性下垂曲线进行控制。实现了并/离网平滑无缝切换。实验仿真结果验证了所提策略的可行性。In the dual mode parallel/off network switching,the voltage and current distortion is caused by the abrupt change of the control command,and adverse effects on the power grid.However,the conventional droop control,although double mode problems are avoided,but it is a differential adjustment,also can produce a certain power fluctuations,thus affecting the stability of the grid.Therefore,based on the analysis of the above problems,this paper proposes an improved control strategy of parallel/off network single mode switching,that is the output voltage amplitude,frequency and power of the inverter are pre synchronized before switching,in the switching process,the improved nonlinear droop curve is used to control.A smooth hand off from the network is achieved.The simulation results verify the feasibility of the proposed method.

关 键 词：双模式切换 单模式切换 预同步 暂态自适应下垂控制 非线性下垂曲线 

分 类 号：TM933[电气工程—电力电子与电力传动]