对J-A和Preisach进行的一项比较研究改善了DC偏差下核心损耗计算的模型
1State Key Laboratory of Power System Operation and Control, Department of Electrical Engineering, Tsinghua University, Beijing, 100084, China.
Scientific reports
|April 24, 2024
概括
这项研究改进了模型,以准确计算在直流偏差下功率变压器核心损耗,防止过热. 增强的J-A-FEM和Preisach-FEM模型为连接到电网的电力系统提供了精确的预测.
科学领域:
- 电气工程 电气工程
- 材料科学 材料科学 材料科学
- 计算电磁学 计算机电磁学
背景情况:
- 电力转换器在电力系统中至关重要,特别是与越来越多的电网连接电力转换器.
- 变压器中的直流偏差显著增加了铁芯损耗,导致过热和运行风险.
- 由于复杂的感应波形扭曲,在直流偏差下准确评估核心损失是具有挑战性的.
研究的目的:
- 开发改进的模型来评估电源变压器中铁芯损耗,这些变压器受到直流偏差的影响.
- 将先进的hysteresis模型集成到有限元法 (FEM) 中,以精确计算核心损失.
- 为了比较增强的J-A-FEM和Preisach-FEM模型的性能.
主要方法:
- 修改 J-A 和 Preisach 模型以考虑直流偏差效应.
- 通过改变构成方程,将歇斯底里模型纳入FEM.
- 为了实验验证,开发了一个层层芯变压器原型.
- 基于准确性,实施和计算成本的J-A-FEM和Preisach-FEM模型的比较分析.
主要成果:
- 改进的J-A-FEM和Preisach-FEM模型提供了在DC偏差下核心损失的准确预测.
- 与修改过的hysteresis模型的FEM集成可以实现精确的核心损失和分布计算.
- 实验验证证证实了开发模型的预测准确性.
- 对比显示了两种模型在数值实现和计算负担方面的差异.
结论:
- 提议的增强的J-A-FEM和Preisach-FEM模型有效地解决了在DC偏差下核心损失评估的挑战.
- 准确的核心损耗计算对于防止变压器过热和确保电力系统可靠性至关重要.
- 该研究为现代电网中的功率变压器的设计和运行提供了有价值的工具.
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