随着高压直流输电工程的不断投产,以及风电项目的增多,越来越多的风电场出现在电网换相换流器高压直流输电(line-commutated-converter based high voltage direct current,LCC-HVDC)受端换流站近区,两者构成的系统存在振荡风险.为此,该文针对直流受端馈入站与近区风电场系统的振荡特性展开研究.首先,建立并验证系统的状态空间模型,基于该模型计算出系统特征值,确定 LCC-HVDC与风电场共同参与的振荡主导模式并进行参与因子分析.进一步地,通过对比是否接入 LCC-HVDC 的主导模式,得到LCC-HVDC 的接入会削弱系统阻尼的结论.最后,从系统额定容量、交流系统短路比、风电场并网线路长度等方面探究系统稳定性的影响因素,并分析系统的不同短路比、潮流比对风机网侧换流器(grid-side converter,GSC)外环控制和换流站定电流控制器性能的影响.
Abstract
With the construction of HVDC transmission projects and the increase of new energy projects,more and more wind farms appear in the near area of the grid commutated-converter based high voltage direct current(LCC-HVDC)receiving converter station,both of which constitute the system with the risk of oscillation.To this end,this paper investigates the oscillation characteristics of the DC receiving feed-in station and the wind farm system in the near zone.First,a state-space model of the system is developed and validated.Based on the model,the system characteristic values are calculated,and the dominant oscillation modes involving LCC-HVDC and wind farms are selected and analyzed as participation factors.Furthermore,by comparing the dominant modes with and without access to LCC-HVDC,it is concluded that the access to LCC-HVDC weakens the system damping.Finally,the influence factors of system stability are explored in terms of system rated capacity,AC system short-circuit ratio,as well as wind farm grid-connected line length.And the effects of different short-circuit and tidal ratios of the system on controller performance are analyzed.
关键词
直驱风电场/电网换相换流器高压直流输电/直流馈入站/耦合振荡/小信号分析/参与因子分析
Key words
direct-drive permanent magnet synchronous generator(D-PMSG)/line-commutated-converter based high voltage direct current(LCC-HVDC)/DC feed-in stations/coupling oscillations/small-signal analysis/participation factor analysis
维普
万方数据