Inertia constant is widely used to evaluate the inertia capability for wind turbines (WTs). However, the method fails to reflect the dynamic characteristics of the inertia and neglects the impacts of controllers. For this issue, this article establishes an inertia function to analyze the dynamic inertia for type-3 WTs. Firstly, the consistency of the power transfer mechanisms between the type-3 WT and synchronous generator (SG) is discussed. Then, a new approach to construct the inertia function is offered according to the phase motion model of SG. On this basis, the impacts of the controllers and operating points on the inertia are explored, and the critical factors are revealed. The analysis results help to understand and optimize the inertia capability of the type-3 WT. Moreover, compared with the conventional inertia constant, the presented inertia function can better reveal the dynamic nature and the influence rule of inertia. Finally, the analysis is validated by IEEE 3-bus test system simulation.

中文翻译：

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基于惯性函数的3型风力发电机组动态惯性评估

惯性常数被广泛用于评估风力涡轮机（WTs）的惯性能力。但是，该方法不能反映惯性的动态特性，而忽略了控制器的影响。针对此问题，本文建立了一个惯性函数来分析3型WT的动态惯性。首先，讨论了3型WT与同步发电机（SG）之间动力传递机制的一致性。然后，根据SG的相移模型，提出了一种构造惯性函数的新方法。在此基础上，探讨了控制器和工作点对惯性的影响，并揭示了关键因素。分析结果有助于理解和优化3型WT的惯性能力。而且，与传统的惯性常数相比，提出的惯性函数可以更好地揭示惯性的动力学性质和影响规律。最后，该分析通过IEEE 3-bus测试系统仿真得到验证。