摘要
目前研究双馈风电机组(DFIG)高电压穿越的重点是单次高压型故障,然而DFIG低电压穿越后,由于无功补偿策略的不合理性,会引发低\高电压复合型故障,对电压二次骤升的暂态分析造成一定影响。因此,在低压恢复阶段的前提下,对电压二次骤升下的转子电流公式进行合理推导,并提出一种转子过电流抑制策略。然后基于故障穿越时系统的无功需求,改进网侧变流器的控制策略。该策略一方面能够减少撬棒保护的投切频率,在一定程度上避免转子侧换流器旁路造成的不可控性;另一方面能够最大限度地向机组给予无功支持,保持直流母线电压处于稳定状态,提升高电压穿越的可靠性。
At present,the focus of research on doubly fed induction generator(DFIG)high voltage ride through is a single high voltage fault.However,after DFIG low voltage ride through,due to the irrationality of the reactive power compensation strategy,a low/high voltage compound fault have be caused,which have a certain impact on the transient analysis of the secondary voltage surge.Therefore,the rotor current formula was reasonably derived under the second voltage surge on the premise of the low voltage recovery stage,and a rotor over-current suppression strategy was proposed.Then,based on the reactive power demand of the system during fault ride through,the control strategy of the grid-side converter was improved.On the one hand,the strategy can reduce the switching frequency of crowbar protection,and to a certain extent avoid the uncontrollability caused by the bypass of the rotor-side converter.On the other hand,it can provide maximum reactive power support to the unit,keep the DC bus voltage in a stable state,and improve the reliability of high voltage ride through.
作者
严雨豪
周步祥
陈实
董申
刘治凡
臧天磊
YAN Yuhao;ZHOU Buxiang;CHEN Shi;DONG Shen;LIU Zhifan;ZANG Tianlei(College of Electrical Engineering,Sichuan University,Chengdu 610065,Sichuan,China;Southwest Electric Power Design Institute Co.,Ltd.of China Power Engineering Consulting Group,Chengdu 610021,Sichuan,China)
出处
《电气传动》
2022年第17期32-39,共8页
Electric Drive
基金
四川省科技计划项目(2020JDRC0049)。
关键词
双馈风电机组
低/高电压穿越
低压恢复阶段
撬棒电路
转子过电流抑制
doubly fed induction generator(DFIG)
low/high voltage ride through
low voltage recovery stage
crowbar circuit
rotor over-current suppression
