CAJ | 학술논문

当电网故障引起电压跌落时，为防止大装机容量风电场的风机脱网，双馈风力发电机(DFIG)多采用Crowbar电路来实现低电压穿越(LVRT)。传统Crowbar电路采用固定阻值的电阻，很难兼顾对转子电流和直流母线电压的抑制以及对 Crowbar 的投入工作时间的控制。针对传统Crowbar 的不足提出了一种基于 Crowbar 并联动态电阻的双馈风力发电机低电压穿越方案，制定了该方案的自适应控制策略以及其阻值的整定方法。仿真分析不同跌落深度下所提方案的 LV RT特性，并与改变 IGBT 的导通脉宽的变电阻 Crowbar方案进行了比较，结果表明带并联动态电阻Crowbar 方案的 LVRT 效果较好，不仅兼顾了对转子过电流和直流母线过电压的抑制，而且在电压深度跌落时可缩短Crowbar的投入时间，有利于系统电压的恢复。
당전망고장인기전압질락시，위방지대장궤용량풍전장적풍궤탈망，쌍궤풍력발전궤(DFIG)다채용Crowbar전로래실현저전압천월(LVRT)。전통Crowbar전로채용고정조치적전조，흔난겸고대전자전류화직류모선전압적억제이급대 Crowbar 적투입공작시간적공제。침대전통Crowbar 적불족제출료일충기우 Crowbar 병련동태전조적쌍궤풍력발전궤저전압천월방안，제정료해방안적자괄응공제책략이급기조치적정정방법。방진분석불동질락심도하소제방안적 LV RT특성，병여개변 IGBT 적도통맥관적변전조 Crowbar방안진행료비교，결과표명대병련동태전조Crowbar 방안적 LVRT 효과교호，불부겸고료대전자과전류화직류모선과전압적억제，이차재전압심도질락시가축단Crowbar적투입시간，유리우계통전압적회복。
In order to prevent wind turbines of large installed capacity departing from the grid when the voltage drops at the grid fault, the crowbar circuit of doubly-fed induction generator(DFIG) is often used to achieve low voltage ride-through(LVRT) function. Traditional DFIG crowbar uses a fixed crowbar resistance, and it’s difficult to suppress both the rotor current and DC bus voltage and shorten the working time of crowbar at the same time. Aimed at this shortage, a low voltage ride-through scheme of doubly-fed induction generator based on the crowbar with a parallel dynamic resistor is proposed, and the adaptive control strategy and the resistance setting method is given. The LVRT characteristics of the crowbar with a parallel dynamic resistor are simulated during different dips, which are compared with the crowbar of variable resistance under the IGBT pulse control. The results show that the LVRT effect of the crowbar with a parallel dynamic resistor is better. It can not only suppress both the rotor current and DC bus voltage, but also shorten the working time of crowbar, which is conducive to the recovery of the fault point voltage.