含异步变速风机的风电场一次调频等值建模与仿真

Equivalent Modeling and Simulation for Primary Frequency Regulation of Wind Farm with Asynchronous Variable-speed Wind Turbines

风机参与系统一次调频目前已成为各国电网对风机并网的基本要求,但是适用于预测控制等算法的大型风电场频率响应动态特性数学描述尚未有充分研究。文中提出了参与调频前运行于最大功率点跟踪模式下的异步变速风机参与一次调频时的全风况出力响应模型,基于小信号增量法获得了不同工况下出力响应的线性化描述,与风机非线性模型对比验证了所提线性化模型的有效性和准确性。此外,在单机线性化模型基础上,基于间隙度量计算将特性相似的风机进行聚类,建立了风电场出力响应等值模型。仿真结果表明,所提等值模型在降低风电场调频模型复杂度的前提下保证了风电场频率响应特性的逼近精度。

The participation of wind turbines in primary frequency regulation has become the basic requirement for grid-connected wind turbines in many countries. However, the mathematical description of dynamic characteristics of frequency response of large-scale wind farms suitable for predictive control algorithms is not yet fully studied. For the asynchronous variable-speed wind turbine operating in the maximum power point tracking mode before participating in frequency regulation, this paper develops a full-mode model of the asynchronous wind turbine participating in the primary frequency regulation. Based on the small-signal increment method, the linearized description of the output response under different operation conditions is obtained. The effectiveness and accuracy of the linearized model are verified by the comparison with the non-linear model of wind turbine. In addition, based on the single-machine linearization model, the similar wind turbines are clustered based on the gap metric calculation, and the equivalent model of wind farm output response is established. The simulation results show that the proposed equivalent model guarantees the accuracy of the frequency response characteristics of wind farm under the premise of reducing the complexity of frequency regulation model.