A Method for Improving the Robustness of linear Kramers-Kronig Validity Tests
A Method for Improving the Robustness of linear Kramers-Kronig Validity Tests
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DOI：
10.1016/j.electacta.2014.01.034
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发表时间：
2014-06-10
影响因子：
6.6
通讯作者：
Ivers-Tiffee, E.
中科院分区：
文献类型：
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作者：
Schoenleber, M.;Klotz, D.;Ivers-Tiffee, E.
提出了一种避免线性Kramers-Kronig有效性检验中因欠拟合和过拟合造成歧义的方法。这是基于观察到待拟合的等效电路模型的参数一旦被选择的模型阶数太高而发生过拟合时就开始退化。因此，引入了一种退化程度的度量，并由此发展了一种准则，利用该准则可以很容易地检测出过拟合。此外，还展示了如何使用所建立的判据来自动地为任何给定的阻抗谱找到合适的模型阶数。因此，无论操作员的具体专业知识如何，都可以获得明确的测试结果。由于它易于使用，因此改进后的测试可以作为一种快速的标准测试，揭示测量的阻抗谱的缺陷。仿真和商用锂离子电池的测量结果证明了所提策略的有效性。(C)2014爱思唯尔有限公司。保留所有权利。
A method is presented of avoiding ambiguities in linear Kramers-Kronig validity tests due to under- and over-fitting. It is based on the observation that the parameters of the equivalent circuit model to be fitted start degenerating as soon as the model order chosen is too high and over-fitting is taking place. Hence, a measure of the degree of degeneration is introduced and-from this a criterion is developed with which over-fitting can be easily detected. Furthermore, it is shown, how the developed criterion can be used to automatically find an appropriate model order for any given impedance spectrum. Hereby, unambiguous test results are obtained irrespective of the specific expertise of the operator. Due to its ease of use the so improved test can serve as a quick standard test revealing defectiveness of measured impedance spectra. The validity of the proposed strategy is demonstrated in simulations as well as on measurements of a commercial Lithium-Ion battery. (C) 2014 Elsevier Ltd. All rights reserved.