CAJ | 학술논문

为分析变速恒频风电机组在不同电网频率下的稳定性，提出了考虑适应电网频率变化的双馈风电机组小干扰稳定性的电磁暂态模型。首先，分析了双馈感应发电机现有常规电磁暂态模型不含电网频率导数项，不能反映电网频率变化的问题，提出了双馈感应发电机改进转子暂态电动势的表达式，并建立了含变流器控制系统在内的双馈风电机组小信号改进模型。其次，采用特征值方法，对不同电网频率运行下采用改进及常规双馈感应发电机电磁暂态模型时的系统特征值进行计算与稳定性分析。最后，建立考虑电网频率变化的双馈风电系统时域仿真模型，分别对不同电网频率及不同负荷扰动下的风电机组有功功率和转速特性进行仿真。理论分析及仿真结果表明，相对常规电磁暂态模型，所提出的双馈风电机组改进模型对电网频率变化更为敏感，可适应频率变化的双馈风电机组小干扰稳定分析。
위분석변속항빈풍전궤조재불동전망빈솔하적은정성，제출료고필괄응전망빈솔변화적쌍궤풍전궤조소간우은정성적전자잠태모형。수선，분석료쌍궤감응발전궤현유상규전자잠태모형불함전망빈솔도수항，불능반영전망빈솔변화적문제，제출료쌍궤감응발전궤개진전자잠태전동세적표체식，병건립료함변류기공제계통재내적쌍궤풍전궤조소신호개진모형。기차，채용특정치방법，대불동전망빈솔운행하채용개진급상규쌍궤감응발전궤전자잠태모형시적계통특정치진행계산여은정성분석。최후，건립고필전망빈솔변화적쌍궤풍전계통시역방진모형，분별대불동전망빈솔급불동부하우동하적풍전궤조유공공솔화전속특성진행방진。이론분석급방진결과표명，상대상규전자잠태모형，소제출적쌍궤풍전궤조개진모형대전망빈솔변화경위민감，가괄응빈솔변화적쌍궤풍전궤조소간우은정분석。
In order to analyze the stability of variable speed wind turbine generator system under different grid frequencies,an electromagnetic transient model of small signal stability analysis for a doubly-fed wind turbine is proposed.The model considers the grid frequency variations.Firstly,literature review shows that the conventional electromagnetic transient model of doubly-fed induction generator (DFIG) cannot reflect grid frequency disturbances due to lack of grid frequency reciprocal items.As such,an improved expression of rotor transient electromotive force is proposed and the small signal improved model of DFIG with its converter control system is established considering the grid frequency disturbance impacts.Then,eigenvalues are calculated and compared by using the improved and traditional electromagnetic transient model under different grid frequencies.Finally,the time-domain simulation model considering grid frequency disturbances is established,and then the active power and the rotor speed performances are simulated under different grid frequencies and different load disturbances. Analytical and simulation results show that compared with the traditional DFIG electromagnetic transient model,the improved model is more sensitive to the grid frequency change,and can be adapted to analyze the stability of doubly-fed wind turbines considering the grid frequency variations.