弱电网下无刷双馈风机稳定性分析及虚拟电感控制策略  

Stability Analysis and Virtual Inductance Control Strategy of BDFIG-based Wind Turbines During Weak Grid Condition

作　　者：徐海亮 王中行 李志 王艳松[1] XU Hailiang;WANG Zhongxing;LI Zhi;WANG Yansong(College of New Energy,China University of Petroleum(East China),Qingdao 266580,Shandong Province,China)

机构地区：[1]中国石油大学(华东)新能源学院,山东省青岛市266580

出　　处：《电网技术》2022年第4期1400-1409,共10页Power System Technology

基　　金：国家自然科学基金项目(52077222);中央高校基本科研业务费(19CX02016A)。

摘　　要：无刷双馈电机(brushless doubly-fed induction generator,BDFIG)由于省去了电刷和滑环等结构,降低了故障率和维护成本,在海上风力发电领域有巨大的应用潜力。然而,无刷双馈风机系统与弱电网的交互作用和失稳机理尚未探明,给其实际应用和商业推广带来困难。为解决该问题,基于小信号建模方法,建立了计及电流环和锁相环影响的BDFIG系统输入导纳模型,探明了电网电压扰动在控制系统中的传递规律。特别是,分析了弱电网条件下,运行点(有功和无功电流)对系统稳定性的影响机理,并据此得出BDFIG系统电流指令的给定依据。同时,探明了虚拟电感参数对系统稳定性的影响机理,提出了一种虚拟电感控制的参数整定方法,以增强弱电网下系统的稳定性。最后,仿真算例验证了理论分析的正确性和虚拟电感控制策略的有效性。In virtue of the elimination of the brushes and the slip rings,the brushless doubly-fed induction generator(BDFIG) is a potential alternative to the well-known DFIG in the wind power generation field due to its high reliability and low maintenance costs.However,the interaction and instability mechanism between the BDFIG-based system and the weak AC grid still remain unaddressed,resulting in some difficulties in its practical application and commercial promotion.In order to settle such problems,the input admittance model of the BDFIG system is established based on the small-signal impedance modeling method,which considers the influence of both the current loop and the phase-locked loop.Then the transmission paths of the grid voltage disturbance in the control system are explored.In particular,the impact mechanism of the operating points(the active and reactive currents) on the system stability under the weak grid condition is estimated in detail.Accordingly,the current references of the BDFIG system are derived.Meanwhile,the effecting pattern of the virtual inductive on the system stability is studied and the parameter tuning method of the virtual inductive control strategy is proposed to enhance the stability of the system.Finally,the simulations verify the correctness of the theoretical analysis and the effectiveness of the proposed control strategy.

关 键 词：弱电网 无刷双馈电机 小信号建模 稳定性分析 虚拟电感控制 

分 类 号：TM721[电气工程—电力系统及自动化]