计及转子侧变换器控制切换模式差异的双馈风电场多机表征方法  

Multi-machine Characterization Method for DFIG Wind Farms Considering Difference of Control Switching Modes of Rotor-side Converters

作　　者：刘素梅 王泽彭 毕天姝 LIU Sumei;WANG Zepeng;BI Tianshu(School of Technology,Beijing Forestry University,Beijing 100083,China;State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources(North China Electric Power University),Beijing 102208,China)

机构地区：[1]北京林业大学工学院,北京市100083 [2]新能源电力系统国家重点实验室(华北电力大学),北京市102208

出　　处：《电力系统自动化》2023年第14期130-139,共10页Automation of Electric Power Systems

基　　金：国家自然科学基金资助项目(52107069);中央高校基本科研业务费专项资金资助项目(2018BLRD02);新能源电力系统国家重点实验室开放课题(LAPS19009)。

摘　　要：受风速、机端电压跌落分布等影响,双馈风电场内机组故障行为特性各异,如何建立保留机群故障特征的风电场等值模型得到广泛关注。然而,仅依靠Crowbar状态表征双馈风电场内机群故障特征的差异性,会出现在轻微故障情况下风电场等值模型精度低的问题。为此,文中通过分析电网故障下场内机组转子侧变换器不同控制模式切换、Crowbar状态切换特性,探明了主导机群控制保护序贯切换模式差异的关键因素。推导了转子侧变换器控制切换模式与机端电压跌落分布、风速分布之间的关联规律,以识别机群转子侧变换器控制模式切换的差异性,从而提出了机群分类方法,以建立风电场多机等值模型。最终,对比分析了不同电网故障场景下所提等值模型、基于有功响应的等值模型、基于Crowbar状态的等值模型和单机等值模型与详细模型相比所提供短路电流幅值误差结果,验证了故障全过程中所提等值模型能更为准确地刻画整个风电场的短路电流幅值变化规律。Due to the influence of wind speed,terminal voltage dip distribution and other factors,the fault behavior characteristics of each doubly-fed induction generator(DFIG)in wind farms vary.How to establish an equivalent model of wind farms that preserves the fault characteristics of the cluster has received widespread attention.However,relying solely on the Crowbar state to characterize the differences in fault characteristics within the DFIG wind farm cluster can lead to the low accuracy of the wind farm equivalent model in the case of minor faults.Therefore,the paper analyzes the switching characteristics of different control modes and Crowbar state switching of the rotor-side converter of DFIG in wind farms under power grid faults,and explores the key factors that affect the differences of the control and protection sequential switching mode of the dominant DFIG cluster.The correlation law between the control switching mode of the rotor-side converter and the distribution of terminal voltage dips and wind speed is derived to identify the differences in the control mode switching of the rotor-side converter in the DFIG cluster.Therefore,a DFIG cluster classification method is proposed to establish a multi-machine equivalent model of the wind farm.Finally,a comparative analysis is conducted on the short-circuit current amplitude error results provided by the proposed equivalent models,active response based equivalent models,Crowbar state based equivalent models,and single-machine equivalent models in different power grid fault scenarios compared with the detailed models.It is verified that the established equivalent models during the entire fault process can more accurately depict the changes in short-circuit current amplitude of the entire wind farm.

关 键 词：双馈风电场 控制切换模式 多机表征 等值模型 短路电流 

分 类 号：TM614[电气工程—电力系统及自动化] TM46