中国电机工程学报2025，Vol.45Issue(22)：8742-8753,中插6,13.DOI:10.13334/j.0258-8013.pcsee.250936
微网链式互联装置改进构网型控制方法
Improvement of Grid-forming Control Strategy for Chain-type Micro-grid Interconnection Devices
摘要
Abstract
The power supply radius in areas with weak grids is limited,accompanied with severe issues such as three-phase imbalance at the end of weak grids and within isolated microgrids.To address these challenges,a chain-type interconnection device suitable for strip-shaped power supply areas and an improved network control strategy are proposed.The device comprises a grid-side converter and a converter on the source and load side,with their DC sides cascaded.Firstly,the control principle of a virtual synchronous generator(VSG)is briefly introduced,and the mechanism behind three-phase voltage unbalance is analyzed.Subsequently,two improved VSG control strategies are proposed.For the grid-side converter,a DC voltage droop control loop is integrated into the VSG active power loop to regulate DC voltage.Additionally,dual second-order generalized integrator(DSOGI)is employed for phase-locking and positive-sequence grid voltage extraction.Positive-sequence grid voltage feedforward control is introduced to achieve balanced grid-side current under unbalanced grid voltage conditions.For the converter on the source and load side,a quasi-proportional resonant control loop is cascaded with the VSG power loop to suppress negative-sequence and zero-sequence voltage components,ensuring three-phase voltage balance-particularly under unbalanced DGs and loads.Finally,the effectiveness and correctness of the proposed control strategies are verified by simulation and experimental results.关键词
网侧电流平衡/改进虚拟同步机控制策略/链式互联装置/三相不平衡机理/三相电压平衡Key words
grid-side current balance/improved virtual synchronous generator(VSG)control strategy/chain interconnection device/three-phase unbalanced mechanism/three-phase voltage balance分类
信息技术与安全科学引用本文复制引用
JIANG Yingwei,LI Hao,LYU Zhipeng,LIN Yi,FA Wei,LIU Haitao,LI Zhen..微网链式互联装置改进构网型控制方法[J].中国电机工程学报,2025,45(22):8742-8753,中插6,13.基金项目
国家电网有限公司科技项目(SGFJJJY00GHJS2400016). Science and Technology Project of State Grid Corporation of China(SGFJJJY00GHJS2400016). （SGFJJJY00GHJS2400016）
