电力系统保护与控制2025，Vol.53Issue(24)：100-110,11.DOI:10.19783/j.cnki.pspc.250119
光伏电站接入柔性直流系统的交流侧不对称故障稳态特征研究
Steady-state characteristics of AC side asymmetrical faults in PV power plants integrated to VSC-HVDC systems
摘要
Abstract
To address the issue that the AC-side fault characteristics of photovoltaic(PV)power plants integrated into VSC-HVDC differ significantly from those of traditional AC systems due to the influence of power electronic devices at both ends,a steady-state fault characteristic analysis method is proposed that incorporates system topology and converter fault control strategies,in order to clarify the sequence-component coupling among devices.First,steady-state fault characteristics of AC-side asymmetric faults in PV power plants connected to VSC-HVDC are analyzed.The results reveal the controllable nature of the output currents from power electronic devices at both ends,as well as the relationship of sequence-component coupling between converter's grid-connected point voltage and its output current.Then,it is emphasized that when the PV power plants adopt the negative-sequence current suppression strategy,the HVDC converter becomes the sole source of negative-sequence current in the system.It is further concluded that,under single-phase-to-ground faults and phase-to-phase faults,the fault phase current differences exhibit a quantitative relationship with the negative-sequence current of the HVDC converter.It is also noted that the negative-sequence current limiting of the converter significantly alters the system's sequence-component characteristics.Finally,the correctness of the steady-state fault characteristic analysis is verified through electromagnetic transient simulations of a large-scale PV power plant integrated into a VSC-HVDC system,providing theoretical and technical support for the research of protection principles in power electronics dominated new power systems.关键词
光伏电站/柔性直流/稳态故障特征/交流故障/控制策略/序分量耦合Key words
PV power plant/VSC-HVDC/steady-state fault characteristics/AC fault/control strategy/sequence-component coupling引用本文复制引用
马红月,李岩,张涛,曹润彬,郑涛,郝治国..光伏电站接入柔性直流系统的交流侧不对称故障稳态特征研究[J].电力系统保护与控制,2025,53(24):100-110,11.基金项目
This work is supported by the National Natural Science Foundation of China(No.U23B20112). 国家自然科学基金项目资助(U23B20112) （No.U23B20112）
