大电机技术
大電機技術
대전궤기술
LARGE ELECTRIC MACHINE AND HYDRAULIC TURBINE
2013年
6期
27-33
,共7页
双馈感应发电机%低电压穿越%撬棒电阻%电磁转矩
雙饋感應髮電機%低電壓穿越%撬棒電阻%電磁轉矩
쌍궤감응발전궤%저전압천월%효봉전조%전자전구
doubly fed induction generator(DFIG)%low voltage ride through(LVRT)%Crowbar%electromagnetic torque
电网故障时双馈感应发电机（doubly fed induction generator，DFIG）会发生转子侧过电流和变换器直流链过电压，同时过电流会造成DFIG电磁转矩的冲击，对风电机组机械系统产生很大的扭切应力冲击。为此，本文首先建立了基于定子磁链定向矢量控制策略的双馈风力发电系统暂态数学模型。在此基础上，研究了撬棒电阻在电网故障条件下，对DFIG过电压过电流以及冲击转矩的影响，同时也对不同双馈电机参数在电网故障时，投入撬棒电阻的过渡过程进行了分析研究，探讨了DFIG采用撬棒保护下低电压穿越过程中的发电机电磁参量峰值特性，深入研究了 Crowbar 电阻取值以及不同双馈电机参数对电网故障下的电压、电流以及转矩冲击的影响。研究结果表明，Crowbar电阻取值既要考虑过电压、过电流的影响，同时还必须考虑冲击转矩的影响，相同容量双馈发电机其Crowbar电阻的取值也会因电机参数的不同而不同。
電網故障時雙饋感應髮電機（doubly fed induction generator，DFIG）會髮生轉子側過電流和變換器直流鏈過電壓，同時過電流會造成DFIG電磁轉矩的遲擊，對風電機組機械繫統產生很大的扭切應力遲擊。為此，本文首先建立瞭基于定子磁鏈定嚮矢量控製策略的雙饋風力髮電繫統暫態數學模型。在此基礎上，研究瞭撬棒電阻在電網故障條件下，對DFIG過電壓過電流以及遲擊轉矩的影響，同時也對不同雙饋電機參數在電網故障時，投入撬棒電阻的過渡過程進行瞭分析研究，探討瞭DFIG採用撬棒保護下低電壓穿越過程中的髮電機電磁參量峰值特性，深入研究瞭 Crowbar 電阻取值以及不同雙饋電機參數對電網故障下的電壓、電流以及轉矩遲擊的影響。研究結果錶明，Crowbar電阻取值既要攷慮過電壓、過電流的影響，同時還必鬚攷慮遲擊轉矩的影響，相同容量雙饋髮電機其Crowbar電阻的取值也會因電機參數的不同而不同。
전망고장시쌍궤감응발전궤（doubly fed induction generator，DFIG）회발생전자측과전류화변환기직류련과전압，동시과전류회조성DFIG전자전구적충격，대풍전궤조궤계계통산생흔대적뉴절응력충격。위차，본문수선건립료기우정자자련정향시량공제책략적쌍궤풍력발전계통잠태수학모형。재차기출상，연구료효봉전조재전망고장조건하，대DFIG과전압과전류이급충격전구적영향，동시야대불동쌍궤전궤삼수재전망고장시，투입효봉전조적과도과정진행료분석연구，탐토료DFIG채용효봉보호하저전압천월과정중적발전궤전자삼량봉치특성，심입연구료 Crowbar 전조취치이급불동쌍궤전궤삼수대전망고장하적전압、전류이급전구충격적영향。연구결과표명，Crowbar전조취치기요고필과전압、과전류적영향，동시환필수고필충격전구적영향，상동용량쌍궤발전궤기Crowbar전조적취치야회인전궤삼수적불동이불동。
For wind turbines with doubly fed induction generator (DFIG), the over-current of the rotor and the over-voltage of the dc-link will occur during grid faults. Furthermore, the dramatic fluctuations of the stator and rotor current result in oscillating of the electromagnetic torque of DFIG, and the high shear stress impact on the wind turbine mechanical systems will be produced. In order to study the influence of the Crowbar resistance to the voltage, current restrictions and the ectromagnetic torque of DFIG during voltage dips, the transient model of DFIG was presented in this paper based on the stator flux oriented vector control strategy. On this basis, the transient behaviors and the peak characteristics of the electromagnetic quantities of DFIG were investigated with different motor parameters and different value of Crowbar resistance during grid faults. The results show that, the value of Crowbar resistor is not only necessary to consider the effects of over-voltage and over-current, but also to consider the impact of the ectromagnetic torque. For the DFIGs with the same capacity, the value of Crowbar resistor will vary for the different motor parameters.
