摘要
针对孤岛微网不对称故障对逆变器的负面影响,以两级式光伏并网逆变器为研究对象,基于传统双二阶广义积分器锁相环(DSOGI-PLL),以提高锁相精度为目的,采用谐波消除模块(HCM)与改进锁频环(SOGI-FLL)融合技术,提出一种DSOGI-PLL优化设计方法。在此基础上,构建一种改进两级式光伏低压穿越(LVRT)优化控制方法。从稳定并网逆变器直流电压和平抑输出功率波动两方面入手,进一步提升微网故障发生时逆变器的故障穿越能力。最后,利用RT-LAB实时仿真平台,构建含光伏并网的孤岛微网模型,通过模拟微网线路不对称故障,验证了所提光伏逆变器改进锁相环以及LVRT优化控制方法的有效性。
Aiming at the negative impact of island microgrid asymmetric faults on the inverter,a two-stage photovoltaic grid-connected inverter is taken as the research object.Based on traditional dual second-order generalized integrator phase-locked loop,aiming to improve phase-locked accuracy,a DSOGI-PLL optimization design method is proposed by using the fusion technology of harmonic cancellation module(HCM)and improved frequency-locked loop(SOGI-FLL).Based on this,an improved two-stage photovoltaic low voltage ride-through(LVRT)optimization control method is constructed.In this method,the DC voltage of the grid-connected inverter is stabilized and output power fluctuation is suppressed to further improve the fault ride-through capability of the inverter when a microgrid fault occurs.Finally,an RT-LAB real-time simulation platform is used to construct an island microgrid model with photovoltaic grid connection.The effectiveness of the proposed improved phase-locked loop and LVRT Optimal Control method for photovoltaic inverters is verified by simulating asymmetric faults in the microgrid lines.
作者
丁保迪
季宇
王永刚
苏剑
李荣
陈继开
DING Bao-di;JI Yu;WANG Yong-gang;SU Jian;LI Rong;CHEN Ji-kai(China Electric Power Research Institute,Bering 100085,China;School of Electrical Engineering,Northeast Electric Power University,Jilin 132012,China;State Grid Shandong Electric Power Company Jinan 250002,China)
出处
《控制工程》
CSCD
北大核心
2021年第10期2060-2069,共10页
Control Engineering of China
基金
国家电网公司总部科技项目(52060018000N)。
关键词
孤岛微电网
不对称故障
锁相环
LVRT
光伏
Island microgrid
asymmetric fault
phase-locked loop
LVRT
photovoltaic
