摘要
弱电网内阻抗大,在接入不平衡负载时,无法维持自身电压的稳定,导致电压三相不平衡、输出功率波动,虚拟同步发电机(VSG)技术作为构网型控制可对弱电网电压提供支撑,但不平衡负载接入下VSG技术无法维持输出电压平衡。对此,提出一种的改进VSG分序解耦控制策略。首先,分析了不平衡负载接入后导致VSG输出电压三相不平衡、功率波动的机理;然后,采用基于双同步坐标系解耦(DDSRF),分离出电网正、负序电压,在dq旋转坐标系下采取正、负序分序控制的策略,控制负序电压分量;最后,搭建了VSG仿真模型,仿真结果表明所提改进VSG分序解耦控制技术可抑制VSG输出的不平衡电压。
The impedance inside weak current network is large,and when unbalanced loads are connected,it is unable to maintain the stability of its own voltage,resulting in three-phase voltage imbalance and output power fluctuations.Virtual synchronous generator(VSG)technology,as a grid-forming control,can provide support for voltage of the weak current network.However,under the connection of unbalanced loads,the VSG technology cannot maintain output voltage balance.To solve this problem,an improved VSG sequence decoupling control strategy is proposed.Firstly,the principle of three-phase imbalance and power fluctuation in VSG output voltage caused by unbalanced load connection is investigated.Secondly,a dual synchronous coordinate system decoupling(DDSRF)is adopted to separate the positive and negative sequence voltages of the power grid,and a positive and negative sequence control strategy is employed to control the negative sequence voltage component in dq rotating coordinate system.Finally,a VSG simulation model is built and the simulation results indicate that the proposed improved VSG sequential decoupling control strategy can suppress the unbalanced voltage output of the VSGs.
作者
黄贤淼
邵尹池
巩宇
刘迪
朱学森
罗家林
HUANG Xianmiao;SHAO Yichi;GONG Yu;LIU Di;ZHU Xuesen;LUO Jialin(Electric Power Science Research Institute,State Grid Jibei Electric Power Co.,Ltd.,Beijing 100045,China;College of Electrical Engineering,Shanghai University of Electric Power,Shanghai 200090,China)
出处
《热力发电》
CAS
CSCD
北大核心
2024年第8期59-67,共9页
Thermal Power Generation
基金
国网冀北电力有限公司科技项目(52018K23000G)。
关键词
构网控制
储能
VSG
不平衡控制
grid-forming control
energy storage
VSG
unbalanced control
作者简介
第一作者:黄贤淼(1997),男,工程师,主要研究方向为储能建模技术,2461902282@qq.com;通信作者:罗家林(1998),男,硕士研究生,主要研究方向为微电网储能控制技术,3142849855@qq.com。
