摘要
在风力发电中,风电场电力汇集系统与大电网耦合会引发高频谐振问题并影响电网电能质量,深入研究电网阻抗频率特性具有重要意义。基于主动干预法,向公共连接点注入一定扰动电流,提出了一种风电网宽频带谐波阻抗测量装置解决方案。此方案采用三相级联H桥变流器作为谐波发生单元,控制部分采用分层控制策略。在100~5000 Hz时,向风电场35 kV公共母线注入不同频率的谐波电流,通过测量注入点处的电压、电流数据,进而获得风电场35 kV端口输入阻抗。提出的测量装置无需整流环节,能够发出幅值和频率均可控的正负序谐波电流,可以获得准确的正/负序谐波阻抗,具有体积小、结构简单、控制可靠的优点。最后详细的Matlab仿真全面验证了系统拓扑及控制策略的有效性。
In wind power generation,the coupling of the wind farm power pooling system with the grid may cause high frequency resonance problems and affect the power quality of the grid.It is therefore important to study the grid impedance frequency characteristics in depth.A wide-band harmonic impedance measurement device is proposed for wind grid based on the active intervention method,which injects a certain disturbance current into the common connection point.This solution uses a three-phase cascaded H-bridge converter as the harmonic generation and a stratified control strategy for the control part.The harmonic currents of different frequencies are injected into the 35 kV bus of the wind farm in the range of 100~5000 Hz,and the input impedance of the35 kV port of the wind farm is obtained by measuring the voltage and current at the injection point.The proposed measurement device does not require rectification and is able to emit positive and negative sequence harmonic currents with controllable amplitude and frequency.The device can obtain accurate positive sequence and negative sequence harmonic impedance with the advantages of small size,simple structure and reliable control strategy.Finally,detailed Matlab simulations have verified the effectiveness of the system topology and control strategy.
作者
于永军
许立国
林子杰
孙冰涵
刘秋降
吴振升
任之杰
YU Yongjun;XU Liguo;LIN Zijie;SUN Binghan;LIU Qiujiang;WU Zhensheng;REN Zhijie(Electric Power Research Institute,State Grid Xinjiang Electric Power Co.,Ltd.,Urumqi,830011,China;Sinohydro New Energy Development Co.,Ltd.,Beijing 100160,China;School of Economics and Management,Tsinghua University,Beijing 100084,China;School of Electrical Engineering,Beijing Jiaotong University,Beijing 100044,China;HiWing General Aviation Equipment Co.,Ltd.,Beijing 100074,China)
出处
《中国电力》
CSCD
北大核心
2022年第11期73-83,共11页
Electric Power
基金
国家电网公司科技项目(SGXJDK00DWJS2100059)
国家重点研发计划资助项目(物联网与智慧城市关键技术及示范,2018YFB2100100)。
关键词
级联H桥
风电网
谐波阻抗测试
电能质量
分层控制
cascaded H-bridge
wind grid
harmonic impedance testing
power quality
stratified control strategy
