电网不平衡时采用串联网侧变换器的DFIG风电系统协调控制  

Coordinated control of a doubly fed induction generator wind turbine with series grid-side converter under unbalanced grid voltage conditions

作　　者：姚骏[1] 廖勇[1] 李辉[1] 

机构地区：[1]重庆大学输配电装备及系统安全与新技术国家重点实验室,重庆400044

出　　处：《电机与控制学报》2010年第12期1-8,共8页Electric Machines and Control

基　　金：国家高技术研究发展计划(863计划)项目(2007AA05Z422);重庆市科委科技计划项目攻关项目(CSTC2008AB3047);输配电装备及系统安全与新技术国家重点实验室自主研究项目(2007DA10512709214)

摘　　要：针对采用串联网侧变换器的双馈感应发电机(doubly fed induction generators,DFIG)风电系统,详细分析电网电压不平衡条件下该系统的运行情况,从抑制不平衡定子电压及维持系统有功功率平衡的角度出发,分别提出电网不平衡时串联网侧变换器和并联网侧变换器的控制策略。与电网不平衡下DFIG系统的传统运行控制方案相比,所提系统协调控制策略无需改变电网不平衡下转子侧变换器的控制策略,简化转子侧变换器的控制并有效提高其运行可靠性;所提方案在实现DFIG系统电磁转矩、直流链电压及系统总输出有功功率无二倍频波动的同时,实现电网不平衡下DFIG定、转子三相电流平衡,进一步提高了DFIG系统运行的稳定性和可靠性。通过对电网不平衡下采用串联网侧变换器的DFIG风电系统和采用传统控制策略的DFIG系统进行了仿真计算和对比分析,验证所提协调控制策略的正确性和有效性。The operation conditions of the doubly fed induction generator（DFIG） wind turbine with series grid-side converter（SGSC） under unbalanced grid voltage conditions are investigated in this paper.In order to restrain the unbalanced stator voltage and maintain the active power balance,the control strategies for the SGSC and parallel grid-side converter（GSC） are proposed respectively.Compared with the traditional control scheme of the DFIG system,the control strategy of the rotor-side converter（RSC） would not be changed during network unbalance,and it is helpful to simplify the control of RSC and improve the operational reliability of RSC.Not only the double supply frequency oscillations in electromagnetic torque,DC-link voltage and total active power output can be eliminated,but also the stator and rotor currents of the system are balanced.The operational stability and reliability of the DFIG system can be further improved with the proposed scheme.The simulations and contrastive analysis between the DFIG system with SGSC and DFIG system with traditional control strategy verify the validity and effectiveness of the proposed coordinated control strategy.

关 键 词：风力发电 双馈感应发电机 电网电压不平衡 串联网侧变换器 协调控制 

分 类 号：TM614[电气工程—电力系统及自动化]