直驱风电场次同步振荡监测系统的构建与应用

Construction and Application of Sub-synchronous Oscillation Monitoring System for Direct-drive Wind Farm

针对风电汇集地区风电场送端并网时频繁出现的次同步振荡现象,文中建立了含多直驱风电机组风电场并网等值模型,并就等值模型对次同步振荡机理进行分析。其次,文中通过同步相量测量装置(PMU),将直驱风电机组以及换流站等监测点都纳入到监测系统,采用监测联络线有功功率振荡波形并结合联络线次同步谐波频率特征进行次同步振荡的判断。仿真结果表明:D-PMSG风电场并网时存在次同步振荡风险,并验证了次同步谐波监测装置与其他扭振监测保护装置的监测记录结果的一致性,从而证明了监测系统的可行性。该监测系统的构建与应用将为后续次同步振荡机理研究以及抑制措施提供借鉴与参考。

For the frequent appearing sub-synchronous oscillation (SSO)phenomena of sending terminal grid-con- nected for wind farm in wind power collection areas,the equivalent model of interconnecting multiple direct drive permanent magnet wind turbine generators (D-PMSGs)to the grid is established and the mechanism of SSO is ana- lyzed by the equivalent model for D-PMSGs in this paper.Then the wind farm,converter station etc the related sites are incorporated into the monitoring system based on synchronized phasor measurement unit (PMU)tool.The sub- synchronous oscillation is judged by detecting the active power oscillation waveform of the tie line and combining with the sub-synchronous harmonic frequency characteristics of the contact line.The simulation results show that the risk of sub synchronous oscillation existed when the D-PMSG wind farms are connected to the grid.The monitoring and recording results of sub-synchronous harmonics monitoring device and other torsional vibration monitoring pro- tection device are basically the same,then it proves the feasibility of the monitoring system.The construction and ap- plication of the monitoring system will provide reference for the follow-up study of the mechanism of synchronous os- cillation and suppression measures.