White-box detailed transformer models are used by manufacturers for predicting internal overvoltages in transformer windings during the lightning impulse test. One such model is the d-factor model, which is based on a lumped-parameter description based on winding discretization with the inclusion of losses via an empirical, frequency-dependent damping factor. This paper shows a procedure for direct inclusion of the d-factor model in electromagnetic transients simulation programs for use in general studies of network overvoltages. Proper utilization of the model's diagonal structure is utilized in combination with real-valued arithmetic for maximum speed in transient simulations, with optional initialization from sinusoidal steady-state conditions. The model can be used both as a terminal equivalent and for calculation of internal voltages with use of an augmented input data set. The method is demonstrated for a single-phase three-winding transformer that is applied in a simulation study of transient resonant voltage buildup in the tertiary winding.

中文翻译：

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用于 EMT 仿真程序的阻尼因子白盒变压器模型的时域实现

制造商使用白盒详细变压器模型来预测雷电冲击测试期间变压器绕组的内部过电压。其中一个模型是 d 因子模型，它基于基于绕组离散化的集总参数描述，并通过经验性的频率相关阻尼因子包含损耗。本文展示了将 d 因子模型直接包含在电磁瞬态仿真程序中的过程，以用于网络过电压的一般研究。模型对角线结构的正确利用与实值算法相结合，可在瞬态仿真中实现最大速度，并可选择从正弦稳态条件进行初始化。该模型既可以用作终端等效项，也可以用于使用增强的输入数据集计算内部电压。该方法针对单相三绕组变压器进行了演示，该变压器应用于三次绕组中瞬态谐振电压积累的仿真研究。