Abstract
Multilayer Ceramic Capacitors (MLCCs) are of paramount importance in electronics and ferroelectric Class II dielectrics enable outstanding energy-density values. However, the non-linear dielectric constant and associated low-frequency large-signal excitation losses of Class II MLCCs may cause critical overheating. A peak-charge based Steinmetz loss model entitled iGSE-CQ is known in literature and allows to accurately calculate MLCC low-frequency large-signal excitation losses under various operating conditions including biased and non-sinusoidal excitation voltage waveforms. Such a macroscopic iGSE-CQ model, however, is inherently limited to a specific MLCC, and in contrast to Steinmetz loss modeling for ferromagnetic inductor cores, the losses of other devices employing the same dielectric material cannot be predicted. Recent literature therefore proposed a microscopic and/or material specific MLCC Steinmetz Model entitled iGSE-CD which allows to calculate the losses of any MLCC of the same dielectric material based upon just a single set of Steinmetz parameters. However, due to the lack of information on the internal device geometry, the iGSE-CD could be verified only indirectly so far by means of a loss normalization based on the device capacitance and rated voltage. In this paper, we demonstrate the feasibility of a microscopic iGSE-CD MLCC loss model enabled by manufacturer data on the internal capacitor structure. The iGSE-CD is verified for two different MLCC series employing a conventional X7R dielectric and a novel Hiteca (with reduced non-linearity) Class II dielectric material with loss estimation error below 22\%. This error results due to component tolerances and is acceptable, especially when compared to the loss calculation based on the datasheet information which can be off by up to a factor of ten. The analysis of the Hiteca dielectric reveals a frequency behavior different to the X7R material, and is discussed in the Appendix of this paper.
Original language | English |
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Pages (from-to) | 107-116 |
Number of pages | 10 |
Journal | IEEE Open Journal of Power Electronics |
Volume | 4 |
DOIs | |
State | Published - 1 Jan 2023 |
Keywords
- AC-DC power converters
- DC-AC power converters
- MLCC
- Multilayer ceramic capacitor
- Steinmetz Equation
- iGSE
- iGSE-C
- inverters
- loss modeling
- power capacitors
- rectifiers
ASJC Scopus subject areas
- Electrical and Electronic Engineering