Quasi-Resonant Flyback Converter as Auxiliary Power-Supply of an 800 V Inductive-Charging System for Electric Vehicles
This paper presents evaluation of quasi-resonant flyback (QRF) dc-dc converter 57W with valley-switching in an emerging application. The QRF was supplied from an 800V variable dc-link and was used as the auxiliary power-supply of a wireless inductive-charging system (ICS). Comparison of state-of-the...
Saved in:
| Main Author: | |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
IEEE
2022-01-01
|
| Series: | IEEE Access |
| Subjects: | |
| Online Access: | https://ieeexplore.ieee.org/document/9919182/ |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1850246202907426816 |
|---|---|
| author | Darko D. Vracar |
| author_facet | Darko D. Vracar |
| author_sort | Darko D. Vracar |
| collection | DOAJ |
| description | This paper presents evaluation of quasi-resonant flyback (QRF) dc-dc converter 57W with valley-switching in an emerging application. The QRF was supplied from an 800V variable dc-link and was used as the auxiliary power-supply of a wireless inductive-charging system (ICS). Comparison of state-of-the-art QRF control ICs is presented and suggestions for their improvements are given. Notes on the power-supply architecture, design items specific for the ICS application, over-power protection, and key-component choice are provided. During experiments several original and novel results are generated. The QRF efficiency graphs in ICS power transfer, ICS stand-by, and constant-load operation are analyzed. The maximum efficiency of 87.1% was reached at 620V and rated load. Moreover, the unique analysis of QRF losses at no-load, showed their quadratic dependency vs. input-voltage. The measured “switching frequency vs. load” graph is presented. It was changeable with load and input-voltage as expected. From Bode plots the bandwidth, phase-margin, and gain-margin are extracted and plotted versus input-power—for the first time. They were changeable with input-voltage and load as expected. Comparison of simulated and measured Bode plots showed that, even when they were not matched, one can still design a Type-2 compensator that ensures stable operation. Evaluation of cross-regulation, when output with 24.1% of total power was regulated, showed that such approach—contrary to the more common of regulating the biggest one—is feasible too. It is discovered that, for a QRF with variable switching frequency, choice of compensator’s zero or the regulated output has influence on its efficiency. The power-thresholds, to ensure valley-switching operation, represented as “input power vs. input voltage” are shown for the first time. Comparison of bandwidth, phase margin, and gain margin vs. input power, between an active-clamped flyback (ACF) and the QRF converters, were discussed. Conclusion is that QRF, for the same specification, cannot have the same compensator as an ACF or conventional flyback dc-dc converter. The difference must be at least in a placement of a zero. |
| format | Article |
| id | doaj-art-f65345f2b7c6454fbee6bec6e8116a39 |
| institution | OA Journals |
| issn | 2169-3536 |
| language | English |
| publishDate | 2022-01-01 |
| publisher | IEEE |
| record_format | Article |
| series | IEEE Access |
| spelling | doaj-art-f65345f2b7c6454fbee6bec6e8116a392025-08-20T01:59:14ZengIEEEIEEE Access2169-35362022-01-011010960910962510.1109/ACCESS.2022.32145269919182Quasi-Resonant Flyback Converter as Auxiliary Power-Supply of an 800 V Inductive-Charging System for Electric VehiclesDarko D. Vracar0https://orcid.org/0000-0002-5906-6464School of Electrical Engineering, University of Belgrade, Belgrade, SerbiaThis paper presents evaluation of quasi-resonant flyback (QRF) dc-dc converter 57W with valley-switching in an emerging application. The QRF was supplied from an 800V variable dc-link and was used as the auxiliary power-supply of a wireless inductive-charging system (ICS). Comparison of state-of-the-art QRF control ICs is presented and suggestions for their improvements are given. Notes on the power-supply architecture, design items specific for the ICS application, over-power protection, and key-component choice are provided. During experiments several original and novel results are generated. The QRF efficiency graphs in ICS power transfer, ICS stand-by, and constant-load operation are analyzed. The maximum efficiency of 87.1% was reached at 620V and rated load. Moreover, the unique analysis of QRF losses at no-load, showed their quadratic dependency vs. input-voltage. The measured “switching frequency vs. load” graph is presented. It was changeable with load and input-voltage as expected. From Bode plots the bandwidth, phase-margin, and gain-margin are extracted and plotted versus input-power—for the first time. They were changeable with input-voltage and load as expected. Comparison of simulated and measured Bode plots showed that, even when they were not matched, one can still design a Type-2 compensator that ensures stable operation. Evaluation of cross-regulation, when output with 24.1% of total power was regulated, showed that such approach—contrary to the more common of regulating the biggest one—is feasible too. It is discovered that, for a QRF with variable switching frequency, choice of compensator’s zero or the regulated output has influence on its efficiency. The power-thresholds, to ensure valley-switching operation, represented as “input power vs. input voltage” are shown for the first time. Comparison of bandwidth, phase margin, and gain margin vs. input power, between an active-clamped flyback (ACF) and the QRF converters, were discussed. Conclusion is that QRF, for the same specification, cannot have the same compensator as an ACF or conventional flyback dc-dc converter. The difference must be at least in a placement of a zero.https://ieeexplore.ieee.org/document/9919182/Active-clamped flybackBode plotscontrolcross-regulationdc-dc converterefficiency change |
| spellingShingle | Darko D. Vracar Quasi-Resonant Flyback Converter as Auxiliary Power-Supply of an 800 V Inductive-Charging System for Electric Vehicles IEEE Access Active-clamped flyback Bode plots control cross-regulation dc-dc converter efficiency change |
| title | Quasi-Resonant Flyback Converter as Auxiliary Power-Supply of an 800 V Inductive-Charging System for Electric Vehicles |
| title_full | Quasi-Resonant Flyback Converter as Auxiliary Power-Supply of an 800 V Inductive-Charging System for Electric Vehicles |
| title_fullStr | Quasi-Resonant Flyback Converter as Auxiliary Power-Supply of an 800 V Inductive-Charging System for Electric Vehicles |
| title_full_unstemmed | Quasi-Resonant Flyback Converter as Auxiliary Power-Supply of an 800 V Inductive-Charging System for Electric Vehicles |
| title_short | Quasi-Resonant Flyback Converter as Auxiliary Power-Supply of an 800 V Inductive-Charging System for Electric Vehicles |
| title_sort | quasi resonant flyback converter as auxiliary power supply of an 800 v inductive charging system for electric vehicles |
| topic | Active-clamped flyback Bode plots control cross-regulation dc-dc converter efficiency change |
| url | https://ieeexplore.ieee.org/document/9919182/ |
| work_keys_str_mv | AT darkodvracar quasiresonantflybackconverterasauxiliarypowersupplyofan800vinductivechargingsystemforelectricvehicles |