Print Email Facebook Twitter A Gradient-Descent Optimization Assisted Gray-Box Impedance Modeling of EV chargers Title A Gradient-Descent Optimization Assisted Gray-Box Impedance Modeling of EV chargers Author Wang, L. (TU Delft DC systems, Energy conversion & Storage) Qin, Z. (TU Delft DC systems, Energy conversion & Storage) Bauer, P. (TU Delft DC systems, Energy conversion & Storage) Date 2023 Abstract Extracting an electric vehicle (EV) charger's input impedance with the analytical model (white-box approach) or the frequency sweep (black-box approach) is limited by the parameter confidentiality or the measurement noise, respectively. To overcome these challenges, a gradient-descent (GD) optimization-based gray-box modeling approach is proposed. To start with, a sensitivity study on the analytical impedance model of an EV charger with a typical controller is carried out to identify the influential frequency range per controller and circuit parameter. On top of that, given an EV charger with unknown control and circuit information, a GD optimization-based algorithm for multiple parameter estimation is designed to identify the unknown controller and circuit parameters based on the measured impedance, by assuming the EV charger is using the typical controller. Then, an analytical input impedance of the black-box EV charger can be obtained. Moreover, the low-accuracy issue commonly encountered when estimating multiple parameters with GD optimization is mitigated with the proposed algorithm. Compared to pure frequency sweep, the proposed approach achieves a higher accuracy for the coupling impedance and a comparable accuracy for the diagonal impedance. The effectiveness of the proposed approach is validated by experimental results. Subject EV ChargingPower Qualityimpedance modelingParameter EstimationGray Box Modelgradient-based optimizationVoltage Source Converter (VSC) To reference this document use: http://resolver.tudelft.nl/uuid:46e5884c-772a-4bef-b243-203a05fa15c2 DOI https://doi.org/10.1109/TPEL.2023.3267151 Embargo date 2023-10-17 ISSN 1941-0107 Source IEEE Transactions on Power Electronics, 38 (7), 8866-8879 Bibliographical note Green Open Access added to TU Delft Institutional Repository 'You share, we take care!' - Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public. Part of collection Institutional Repository Document type journal article Rights © 2023 L. Wang, Z. Qin, P. Bauer Files PDF A_Gradient_Descent_Optimi ... argers.pdf 9.12 MB Close viewer /islandora/object/uuid:46e5884c-772a-4bef-b243-203a05fa15c2/datastream/OBJ/view