电网对称故障下双馈风力发电机的虚拟同步控制策略

发布时间：2018-03-23 14:38

本文选题：双馈风力发电机　切入点：虚拟同步控制　出处：《电力系统自动化》2017年20期

【摘要】：将虚拟同步控制策略运用于双馈感应发电机(DFIG)变频器控制,可使DFIG为电网提供有惯量的频率与电压支撑。但现有虚拟同步控制策略主要关注DFIG对同步发电机机电动态特性的模拟,未考虑DFIG的电磁暂态过程。分析了基于虚拟同步控制的DFIG在电网对称故障下的电磁暂态特性,指出了现有虚拟同步控制策略存在的两大缺陷:无法完全模拟同步电机故障暂态下的电磁关系,且无法抑制转子过电流。提出了一种适用于电网对称故障的DFIG暂态电压补偿虚拟同步控制策略,即通过补偿转子控制电压的暂态分量来抵消或削弱转子暂态反电势对转子过电流的影响。通过仿真对比了现有虚拟同步控制策略与所提策略对DFIG的控制效果,证明了所提虚拟同步控制策略不仅具备更好的惯性支撑能力,同时可显著抑制DFIG转子过电流与电磁转矩暂态冲击,并对系统进行无功支撑,有效提高了DFIG不间断运行能力与电网故障恢复能力。
[Abstract]:The virtual synchronous control strategy is applied to the control of DFIGG frequency converter of doubly-fed induction generator (DFIGG). DFIG can provide inertial frequency and voltage support for power grid, but the existing virtual synchronization control strategy mainly focuses on the simulation of electromechanical dynamic characteristics of synchronous generator by DFIG. Electromagnetic transient process of DFIG is not considered. The electromagnetic transient characteristics of DFIG based on virtual synchronous control under symmetrical fault of power network are analyzed. Two defects of the existing virtual synchronous control strategy are pointed out: the electromagnetic relationship under the fault transient condition of synchronous motor can not be completely simulated. A virtual synchronous control strategy for DFIG transient voltage compensation is proposed, which is suitable for symmetrical fault of power network. That is, the transient component of rotor control voltage is compensated to offset or weaken the effect of rotor transient reverse EMF on rotor overcurrent. The control effect of the existing virtual synchronous control strategy and the proposed strategy on DFIG is compared by simulation. It is proved that the proposed virtual synchronous control strategy not only has better inertial support ability, but also can significantly suppress the transient impact of DFIG rotor overcurrent and electromagnetic torque, and support the system reactive power. The ability of DFIG uninterrupted operation and power grid fault recovery is improved effectively.
【作者单位】：电力系统及发电设备控制和仿真国家重点实验室清华大学;
【基金】：国家自然科学基金资助项目(U1510208)~~
【分类号】：TM315

【相似文献】