电网电压对称跌落时双馈风力发电系统的暂态分析与控制  

Transient Analysis and Control for a Doubly Fed Generation under Symmetrical Voltage Dips

作　　者：吴国祥[1,2] 吴国庆[1] 倪红军[1] 茅靖峰[1] 张旭东[1] 刘鸿泉[1] 

机构地区：[1]南通大学电子信息学院江苏省风能应用技术工程中心,江苏南通226019 [2]上海交通大学电子信息与电气工程学院风力发电研究中心,上海200240

出　　处：《电气传动》2013年第10期3-8,共6页Electric Drive

基　　金：国家自然基金(60974049;61273151;61004053);中国博士后基金(2012M511092);江苏省高校自然基金(10KJD480004)

摘　　要：通过对电网对称跌落时双馈电机内部电磁过渡过程的分析,推导出了双馈电机在电网故障情况下定子磁链、转子电压的数学表达式。提出了一种分段控制策略,把故障分为2个阶段,第1阶段采用主动Crow bar保护,使定子磁链和转子电压快速衰减;第2阶段恢复变换器的励磁控制,注入退磁电流和无功电流,有效地实现了双馈电机的故障穿越。分段控制策略缩短了Crowbar保护时间,有助于电网的快速恢复。仿真结果证实了所提出控制策略的有效性与正确性。The electromagnetic transient response of DFIG under symmetrical voltage dips was analyzed firstly,based on which the equations of stator flux and rotor voltage were obtained.A sectional control strategy was proposed,dividing the fault time into two stages,the active Crowbar protection is adopted in the first stage to make the stator flux and the rotor voltage decay rapidly,the converter excitation control is resumed in the second stage to inject demagnetizing current and reactive current,low voltage ride through of DFIG is implemented effectively.The proposed control strategy notably reduces the Crowbar activation time,helping grid recovery under system fault.The simulation results of a complete system are included,demonstrating the viability of the proposed control strategy.

关 键 词：双馈电机 电压跌落 暂态分析 CROWBAR电路 低电压穿越 分段控制 

分 类 号：TM614[电气工程—电力系统及自动化]