中国电机工程学报2025，Vol.45Issue(20)：7962-7973,中插10,13.DOI:10.13334/j.0258-8013.pcsee.241019
跟网-构网光伏与火电打捆经传统直流外送系统次同步扭振机理研究
Research on Sub-synchronous Torsional Vibration Mechanism for Grid-following and Grid-forming Photovoltaic and Thermal Power Bundling System via LCC-HVDC Transmission
摘要
Abstract
In the scenario of large-scale new energy and thermal power bundling system via line commutated converter-based high voltage direct current(LCC-HVDC)transmission,the variation characteristics of sub-synchronous torsional interaction(SSTI)damping under different power supply ratios are still unclear,and the proportion of grid-forming(GFM)converters on SSTI damping is unknown.This paper establishes the state space model and the motion equation model for photovoltaic(PV)with grid-following(GFL)-based and GFM-based converters and thermal power bundling system via LCC-HVDC transmission.Multiple paths reflecting the SSTI damping characteristics are decomposed.Subsequently,in the case of pure GFL-based PV,the damping variation characteristics of the SSTI mode under different thermal-PV ratios are investigated.The minimum proportion of thermal power to ensure the stable transmission of rated DC power is obtained,and the key path dominating the damping changing trend of the SSTI mode is identified.Furthermore,the influence characteristics of the GFM-based PV power proportion on SSTI mode damping are analyzed.The minimum proportion of GFM-based converters to stabilize the system with low thermal power proportion is calculated,and its influence mechanism is revealed according to the damping characteristics of different paths.The results indicate that,when the proportion of new energy power output is too high,the supporting capacity of GFL-based converters for the weak AC grid is insufficient,leading to the weakening of SSTI damping,when GFM-based converters undertake higher proportion of power output instead of GFL-based converters,the negative impact on AC grid caused by the insufficient support capacity of GFL-based converters can be weakened,i.e.the inclusion of GFM-based converter in the PV power plant can improve the SSTI damping.关键词
跟网型控制/构网型控制/电网换相换流器高压直流输电/次同步扭振互作用Key words
grid-following control/grid-forming control/line commutated converter-based high voltage direct current(LCC-HVDC)/sub-synchronous torsional interaction(SSTI)分类
信息技术与安全科学引用本文复制引用
张加卿,郭春义..跟网-构网光伏与火电打捆经传统直流外送系统次同步扭振机理研究[J].中国电机工程学报,2025,45(20):7962-7973,中插10,13.基金项目
国家自然科学基金(面上基金项目)(52277093).Project Supported by National Natural Science Foundation of China(General Program)(52277093). （面上基金项目）
