基于负电阻效应的风电场宽频振荡风险评估方法

Risk Assessment Method for Wide-band Oscillation of Wind Farms Based on the Negative Resistance Effect

针对大规模风电并网引起的宽频振荡问题,基于风力发电机组的频域阻抗模型,从负电阻效应理论出发提出一种适用于工程应用的风电场级宽频振荡风险评估方法。结合山东省内某直驱风电场的收集资料,采用该方法对该风电场的宽频振荡风险进行评估,详细介绍该方法的应用流程,重点对风力发电机组的频域阻抗建模方法、风电场的阻抗建模方法及风电场级振荡风险评估方法进行阐述,验证该方法的实用性。算例研究表明,所提方法具有良好的工程实用性,风电机组的端口阻抗确实存在一定的负电阻效应频段,可能会引起一定的宽频振荡问题;且其负电阻效应频段受工况影响较大,在评估风电场级的宽频振荡风险时需要特别考虑工况的影响。

Aiming at the wide-band oscillation problems caused by large-scale wind power grid-integration,a practical risk assessment method for wide-band oscillation of wind farm is proposed based on the frequency-domain impedance model of wind generator and the negative resistance effect theory.Furthermore,combined with the collecting data of one wind farm with directdrive wind generator in Shandong,this method is applied to evaluate the wide-band oscillation risk of the wind farm.Firstly,the paper introduces the application process of this method,and then especially presents the modeling method of wind power generator and wind farm and the oscillation risk assessment method of wind farm.The results shows that the proposed method is very practical.In addition,it indicates that in the the port impedance of wind generators,some certain frequency band can have negative resistance effect and can cause some wide-band oscillation issues.In addition,the frequency band of the negative resistance effect is greatly affected by the operating conditions,thus the influence of the operating conditions should be particularly considered,while evaluating the wide-band oscillation risk of wind farm.