【作者】 姚骏； 刘奥林； 李清； 陈知前； 杜红彪；

【Author】 YAO Jun,LIU Ao-lin,Li Qing,CHEN Zhi-qian,DU Hong-biao(State Key Laboratory of Power Transmission Equipment & System and New Technology(Chongqing University),Shapingba District,Chongqing 400044,China)

【机构】 输配电装备及系统安全与新技术国家重点实验室(重庆大学)；

【摘要】 新的电网运行规程要求风力发电系统在电网出现严重不对称短路故障时仍能保持不脱网运行,且风电系统可按要求为电网提供暂态支持。本文针对含直流侧并联飞轮储能单元的永磁直驱风力发电系统,从稳定电网故障时直流母线电压以及充分利用网侧变换器电流容量实现暂态无功支持的角度出发,设计了含飞轮侧变换器、电机侧变换器以及电网侧变换器的协调控制策略。详细推导并分析了电网不对称故障下发电系统的暂态无功极限,并提出了合适的网侧变换器正负序电流分配措施,为风电场实现暂态过程中无功功率的合理控制提供参考依据。所提控制方案在故障过程中实现直流电压稳定控制的基础上,还可实现系统3种可供选择的独立运行模式,进一步有效提高了系统的低电压穿越运行性能。更多还原

【Abstract】 The new grid code requires that the wind power generation system can still keep connecting with the grid to provide the transient support to the grid under serious asymmetric short-circuit faults.For the permanent magnet direct-driven wind power generation system with the dc-link flywheel energy storage unit,a coordinated control strategy for the flywheel motor-side converter,generator-side converter,and grid-side converter was proposed to stably control the dc-link voltage and provide the transient reactive power support under grid fault.The transient reactive power limits under asymmetrical grid faults was derived,and the positiveand negative-sequence current allocation method was discussed.The proposed control strategy can not only keep the dc-link voltage stable,but also realize the three independently selective control targets,effectively enhancing the low voltage ride through operation performance of the system.更多还原