Research on the Voltage Supporting Capability of Multi-VSC-HVDC Subsystems Operation Strategy to Receiving-end LCC-HVDC Network in Weak AC Grid  

作　　者：Tao Li Yongli Li Yuchen Zhu 

机构地区：[1]IEEE [2]the School of Electrical Automation and Information Engineering,Tianjin University,Tianjin,300072,China [3]CES

出　　处：《CES Transactions on Electrical Machines and Systems》2023年第1期11-20,共10页中国电工技术学会电机与系统学报（英文）

基　　金：supported by the National Natural Science Foundation of China-State Grid Joint Fund for Smart Grid(No.U2066210).

摘　　要：For the hybrid multi-infeed HVDC system in which the receiving-end grid is a strong AC grid including LCC-HVDC subsystems and multiple VSC-HVDC subsystems,it has higher voltage support capability.However,for weak AC grid,the voltage support capability of the multi-VSC-HVDC subsystems to the LCC-HVDC subsystem(voltage support capability-mVSCs-LCC)can resist the risk of commutation failure.Based on this consideration,this paper proposes an evaluation index called Dynamic Voltage Support Strength Factor(DVSF)for the hybrid multi-infeed system,and uses this index to qualitatively judge the voltage support capability-mVSCs-LCC in weak AC grid.In addition,the proposed evaluation index can also indirectly judge the ability of the LCC-HVDC subsystem to suppress commutation failure.Firstly,the mathematical model of the power flow of the LCC and VSC networks in the steady-state is analyzed,and the concept of DVSF applied to hybrid multi-infeed system is proposed.Furthermore,the DVSF index is also used to qualitatively judge the voltage support capability-mVSCs-LCC.Secondly,the influence of multiple VSC-HVDC subsystems with different operation strategies on the DVSF is analyzed with reference to the concept of DVSF.Finally,the indicators proposed in this paper are compared with other evaluation indicators through MATLAB simulation software to verify its effectiveness.More importantly,the effects of multi-VSC-HVDC subsystems using different coordinated control strategies on the voltage support capability of the receiving-end LCC-HVDC subsystem are also verified.

关 键 词：Hybrid multi-infeed HVDC system Voltage support Multi-VSC-HVDC LCC-HVDC Commutation failure DVSF Control strategy 

分 类 号：TM721.1[电气工程—电力系统及自动化]