IEC 61400-21-1:20 19包括: ·用于表征并网风力涡轮机的电气特性的待确定的量的定义和规范； ·用于量化电特性的测量程序； ·评估符合电气连接要求的程序，包括评估部署在特定地点时风力涡轮机类型预期的电能质量。 测量程序适用于三相并网的单个风力涡轮机。测量程序对任何尺寸的风力涡轮机都有效，尽管IEC 61400的这一部分仅要求按照IEC 61400的这一部分的规定对打算连接到供电网络的风力涡轮机类型进行测试和表征。 本第一版取消并取代第二版61400-21 200 8年出版。此版本包括以下与61400-21相关的新项目: a)频率控制测量； b)更新的无功功率控制和能力测量，包括电压和cos φ控制； c)惯性控制响应测量； d)过电压穿越测试程序； e)基于风力涡轮机能力更新欠压穿越测试程序； f)谐波评估的新方法。

IEC 61400-21-1:2019 includes:
· definition and specification of the quantities to be determined for characterizing the electrical characteristics of a grid-connected wind turbine;
· measurement procedures for quantifying the electrical characteristics;
· procedures for assessing compliance with electrical connection requirements, including estimation of the power quality expected from the wind turbine type when deployed at a specific site.
The measurement procedures are valid for single wind turbines with a three-phase grid connection. The measurement procedures are valid for any size of wind turbine, though this part of IEC 61400 only requires wind turbine types intended for connection to an electricity supply network to be tested and characterized as specified in this part of IEC 61400.
This first edition cancels and replaces the second edition of 61400-21 published in 2008. This edition includes the following new items with respect to 61400-21:
a) frequency control measurement;
b) updated reactive power control and capability measurement, including voltage and cos φ control;
c) inertia control response measurement;
d) overvoltage ride through test procedure;
e) updated undervoltage ride through test procedure based on Wind Turbine capability;
f) new methods for the harmonic assessment.