摘要
采用柔性直流输电技术送出是大规模海上风电的发展趋势。由于电流控制型的海上风电–柔直并网系统隔离了风电场的惯量,电压源控制方式成为应对新能源主导电力系统稳定运行的一种有效途径。现有海上风电–柔直并网系统的电压源控制研究多集中于控制实现与稳态特性方面,而针对该系统故障控制方面的研究十分匮乏。该文提出一种具备故障穿越能力的海上风电–柔直并网系统自同步电压源控制策略。在受端换流器中,通过子模块能量与同步发电机转子的类比及直流侧的解耦控制,兼顾了对直流母线电压的灵活控制和对电网频率的无锁相环自同步,并改善了通过直流母线电压向送端换流器传递电网频率时的抗扰性能。送端换流器从直流电压中提取电网频率并镜像到其交流侧,辅助海上风电场实现对电网的惯量响应。进一步地,设计受端换流器的电网故障穿越策略,在实现对输出电流限幅的同时,确保了受端换流器的功角稳定。最后,在PSCAD/EMTDC软件中通过仿真验证所提控制方法的有效性。
The grid integration of large-scale offshore wind power via VSC-HVDC transmission has become the development trend.Since the current vector controlled VSC-HVDC system and the offshore wind farm(OWF)present no inertia to the grid,the voltage source control is becoming an effective way to deal with the stable operation problem of power systems dominated by renewable energy.Current researches on the voltage source control of the VSC-HVDC system and the OWF mainly focus on the control implementation and steady-state characteristics.However,the research on fault control of this system is very scarce.Therefore,this paper proposed a self-synchronizing voltage source control strategy for the VSC-HVDC system and the OWF with fault ride-through capability.In the receiving end converter(REC),the internal energy stored in sub-module capacitors was utilized to emulate the synchronous generator rotor,and the DC voltage was decoupled with the submodule capacitors’voltage.With the proposed control strategy,both flexible DC voltage control and self-synchronizing capability can be achieved.The anti-interference performance was also improved when using the DC bus voltage to transmit the grid frequency to the sending-end converter and the OWF.Furthermore,the grid fault-ride-through strategy of the REC was designed to limit the output current and ensure the power angle stability.Finally,the effectiveness of the proposed control strategy can be verified in PSCAD/EMTDC.
作者
杨仁炘
张琛
蔡旭
施刚
李建华
缪源诚
曹路
YANG Renxin;ZHANG Chen;CAI Xu;SHI Gang;LI Jianhua;MIAO Yuancheng;CAO Lu(Key Laboratory of Control of Power Transmission and Conversion(Shanghai Jiao Tong University),Ministry of Education,Minhang District,Shanghai 200240,China;East China Branch of State Grid Corporation of China,Pudong New Area,Shanghai 200120,China)
出处
《中国电机工程学报》
EI
CSCD
北大核心
2022年第13期4823-4834,共12页
Proceedings of the CSEE
基金
国家电网有限公司华东分部科技项目(52080020006A)。
关键词
柔性直流输电
海上风电场
自同步电压源型控制
惯量响应
电网故障穿越
模块化多电平变换器
VSC-HVDC transmission
offshore wind farm
self-synchronizing voltage source control
inertia response
grid fault ride-through
modular multilevel converter
