Existing empiricalcore loss models for symmetric trapezoidal flux waveform (T z FW) still suffer some issues such as the inaccuracy and the complexity. These issues are mainly due to the lack of an accurate model of the relaxation loss generated during the off-time. This paper aims to understand the relaxation loss and develop an accurate model using the superposition technique. The developed model gives an accurate prediction of the on-time loss and the relaxation loss and shows the dependency of each on the duty cycle. The research shows that the core loss at low duty cycle is several times the core loss at full duty cycle. The developed model is verified with experimental results and compared to the Improved Steinmetz equation (ISE). The model error is reduced to lower than 15% compared to 50% of the ISE. Finally, an easy method using multiplication factors with the ISE model is given to simplify the developed model.

中文翻译：

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对称梯形磁通密度波形的磁芯损耗计算


现有的对称梯形磁通波形（T z FW）的经验磁芯损耗模型仍然存在一些问题，例如不准确和复杂性。这些问题主要是由于缺乏关断期间产生的弛豫损耗的准确模型造成的。本文旨在了解弛豫损失并使用叠加技术开发准确的模型。开发的模型可以准确预测接通时间损耗和弛豫损耗，并显示每个损耗对占空比的依赖性。研究表明，低占空比时的磁芯损耗是全占空比时的磁芯损耗的数倍。所开发的模型通过实验结果进行了验证，并与改进的斯坦梅茨方程（ISE）进行了比较。与 ISE 的 50% 相比，模型误差降低至 15% 以下。最后，给出了一种使用 ISE 模型乘法因子的简单方法来简化所开发的模型。