无锁相环直接功率控制双馈感应发电机系统阻抗建模和稳定性分析

随着新能源渗透率的日益升高,基于双馈感应发电机(double fed induction generator,DFIG)的风力发电机组在电力系统中的比重越来越大。无锁相环直接功率控制(direct power control,DPC)不仅可以提高DFIG的动态响应能力,而且可避免锁相环对功率控制动态性能的影响。针对基于无锁相环DPC的DFIG系统接入弱电网下的稳定性问题,该文通过建立无锁相环DPC的DFIG系统阻抗模型,分析了其频率耦合特性及其对稳定性的影响,进而构建等效单输入单输出阻抗模型,实现控制参数和运行工况对系统稳定性的敏感性分析。最后构建仿真模型,对研究内容进行仿真验证。

Impedance Modeling and Stability Analysis of Direct Power Controlled Doubly Fed Induction Generator System Without Phase-locked Loop

With the increasing penetration of renewable energy,wind turbines based on doubly fed induction generators(DFIG) are becoming more and more important in the power system.The direct power control(DPC) without phase-locked loop(PLL) can improve the dynamic response capability of DFIG,and avoid the influence of PLL on the dynamic ability of power control.Aiming at the stability performance of the DFIG system based on DPC without PLL connected to the weak grid,the impedance of DFIG system based on DPC without PLL was developed,and the frequency coupling characteristics in the whole frequency band was analyzed.Therefore,an equivalent single-input single-output(SISO) impedance model was developed to achieve the parameter sensitivity analysis considering the control parameters and operation condition.Finally,the simulation model was developed to validate the developed model and analysis by simulation results.