Inductive Wireless Power Transfer Systems for LowVoltage and HighCurrent Electric Mobility Applications: Review and Design Example
Abstract
:1. Introduction
1.1. Overview
1.2. Research Motivation on IPT Systems for LowVoltage Applications
 From the design perspective, 60 V is considered the upper limit of DC to be safe to touch; and 48 V is safe to touch, hence ground return through the body is possible. Safety and protection requirements are reduced drastically. Further, it is safe to handle the vehicle during any accidents and HVtrained technicians are not needed for maintenance.
 In a 48 V battery, more cells are connected in parallel compared to the highvoltage cells, it is easy to balance the cell voltage and this improves the available energy content.
 Auxiliary components such as turbochargers, intercoolers, HVAC pumps, and EPS motors for 48 V that have already been developed for HEVs can be used.
 No need for additional converters for the auxiliary equipment.
 This voltage level helps to produce betterquality components costeffectively and reduces overall system costs.
 It demands a larger amount of current, resulting in higher power losses for the same power level as the highvoltage drive train.
 Cables with a larger diameter are needed, routing of cables inside limited space will be challenging.
 Maximum speed is limited for a 48 V drive train.
 The 48 V system efficiency is low compared to highvoltage systems.
1.3. Paper Contribution and Structure
 (1)
 This paper intends to provide a review map of compensation selections, control strategies, and power electronic architectures of IPT technology aiming for lowvoltage and highcurrent applications. In which challenges and trends are identified and discussed.
 (2)
 A design concept is proposed as a case study with the verification of Ansys Maxell software and simulation results. In this paper, a high stepdown 400 V/48 V IPT system is proposed to address two main issues:
 Firstly, highcurrent stress on the receiver side and output rectifiers can be reduced due to the proposed asymmetrical compensation structure for the dual decoupled coils (BP) and LCCLCC compensation configuration.
 Secondly, the passive current sharing technique is used to significantly improve current balancing between two sets of receiver coils (BP), resonant tanks (LCCLCC), and output rectifiers under resonant component tolerance and misalignment scenarios. The resonant capacitor and inductor in each receiver are connected in parallel without requiring extra components or control loop design.
2. Magnetic Coupler Pads
2.1. Coil Pad Structures
 A planar spiral coil with a square or rectangular shape is called a square/rectangular coil and is considered a closed variant of CP [50]. Therefore, it is also a suitable coil structure for EV chargers due to the convenience of installation. This coil structure is also simple to manufacture and shows symmetric characteristics. Better lateral misalignment tolerance compared to the circular coil. Lateral tolerance is higher along the longer side than the shorter side [55].
 In circular, rectangular, square, and helical coil structures, only a pair of coils is used for coupling. Budhia et al. [16,56] proposed a double D (DD) coil system as shown in Figure 5c. The flux generated by this structure is bipolar and single sided in nature, this coil configuration shows better performance than unipolar pads such as circular and rectangular [47]. In addition, the fundamental height of the flux path is proportional to half the length of the pad resulting in a higher coupling coefficient called intrapad coupling [16]. These coils are magnetically in parallel and electrically in series. Thus, the unwanted leakage flux path at the rear side of the coil pairs is reduced. DD pad is commonly used as a transmitter and has interoperable with different receiver topologies. However, the conductor length and ohmic loss are higher, so it is not suitable to be applied on the receiver side of lowvoltage and highcurrent IPT systems. The selfinductance of the DD coil is almost 1.7 times the selfinductance of the rectangular coil with the same dimension.
 DD coil only couples the horizontal component of the flux. Misalignment tolerance can be improved further by placing a third coil in the DD coil’s center. This third coil is aligned in special quadrature to the DD coils, and it helps to capture perpendicular flux [56]. This threecoil structure is a modified version of the DD structure called DDQ as shown in Figure 5d. In a perfectly designed DDQ coil, the series connected DD coil and the Q coils are mutually decoupled so these can be tuned and controlled separately [48]. It is demonstrated that the charging zone of the DDQ system is five times larger than that of a circular pad of comparable size [16]. However, DDQ requires more copper wire compared to others and complex design process.
 A bipolar (BP) coil is a multicoil configuration with a bipolar flux path. There are two identical, partially overlapped coils in a BP pad. The top view and simulation model of the BDD coil are shown in Figure 5e. It is commonly adopted on the secondary side. Overlapping of two similar coils helps to cancel out the flux, this concept is used to achieve the decoupling [57]. The superior characteristics BP coil are the remarkable increase in the charging zone and the lateral misalignment tolerance. The benefit of such decoupled coils is that they can be tuned and regulated separately.
2.2. Comparison
3. Compensation Networks
 Minimized reactive circulating current by canceling leakage inductance in the primary HFI and secondary rectifier. As a result, maximum power transfer and system efficiency are achieved.
 Allow high switching operation due to softswitching characteristics such as zero voltage switching (ZVS) and zero current switching (ZCS) in power devices.
 Avoid bifurcation and increase the tolerance of the system for misalignment [60].
 Implement constant current (CC) or constant voltage (CV), which is suitable for battery charging of EV applications [42].
 Improving the misalignment tolerance [63].
3.1. Single Element Compensation Networks
3.2. MultiElement Compensation Networks
Compensation Topologies  Operating Resonant Frequency  Output Characteristics  Load Output  ZPA 

SS [64,65,66,67]  ${f}_{o}=\frac{1}{2\pi \sqrt{{L}_{1}{C}_{1}}}=\frac{1}{2\pi \sqrt{{L}_{2}{C}_{2}}}$  CC  ${i}_{O}=\frac{{V}_{in}}{{\omega}_{o}M}$  Yes 
SP [68]  ${f}_{o}=\frac{1}{2\pi \sqrt{{(L}_{1}\frac{{M}^{2}}{{L}_{2}}}){C}_{1}}=\frac{1}{2\pi \sqrt{{L}_{2}{C}_{2}}}$ Resonant frequencycoupling dependent  CV  ${V}_{O}=\frac{{V}_{in}{L}_{2}}{M}$  Yes 
PS with ${L}_{x}$ [65]  ${f}_{o}=\frac{1}{2\pi \sqrt{{L}_{1}{C}_{1}}}=\frac{1}{2\pi \sqrt{{L}_{2}{C}_{2}}}$ And ${L}_{1}={L}_{x}$  CV  ${V}_{O}=\frac{{V}_{in}M}{{L}_{2}}$  Yes 
PP with ${L}_{x}$ [65]  ${f}_{o}=\frac{1}{2\pi \sqrt{{(L}_{1}\frac{{M}^{2}}{{L}_{2}}}){C}_{1}}=\frac{1}{2\pi \sqrt{{L}_{2}{C}_{2}}}$ And ${L}_{x}={L}_{1}\frac{{M}^{2}}{{L}_{2}}$ Resonant frequencycoupling dependent  CC  ${i}_{O}=\frac{{MV}_{in}}{{\omega}_{o}{(L}_{1}\frac{{M}^{2}}{{L}_{2}}){L}_{2}}$  Yes 
S/SP [70,71,72,73,74]  ${f}_{o}=\frac{1}{2\pi \sqrt{{L}_{1}{C}_{1}}}=\frac{1}{2\pi \sqrt{{L}_{2}{C}_{2}}}=\frac{1}{2\pi \sqrt{{L}_{M}{C}_{3}}}$ Resonant frequencycoupling dependent  CV  ${V}_{O}={V}_{in}$  Yes 
LCLC [75,76]  ${f}_{o}=\frac{1}{2\pi \sqrt{{L}_{1}{C}_{1}}}=\frac{1}{2\pi \sqrt{{L}_{2}{C}_{2}}}$ And ${L}_{1}={L}_{f1},{L}_{2}={L}_{f2}$  CC  ${i}_{O}=\frac{{MV}_{in}}{{\omega}_{o}{{L}_{f1}L}_{f2}}$  Yes 
SLCC [77,78,79]  ${f}_{o}=\frac{1}{2\pi \sqrt{{L}_{1}{C}_{1}}}=\frac{1}{2\pi \sqrt{{L}_{f}{C}_{f}}}=\frac{1}{2\pi \sqrt{{(L}_{2}{L}_{f}){C}_{2}}}$  CV  ${V}_{O}=\frac{{V}_{in}{L}_{f}}{M}$  Yes 
LCCS [80,81]  ${f}_{o}=\frac{1}{2\pi \sqrt{{L}_{2}{C}_{2}}}=\frac{1}{2\pi \sqrt{{L}_{f}{C}_{f}}}=\frac{1}{2\pi \sqrt{{(L}_{1}{L}_{f}){C}_{1}}}$  CV  ${V}_{O}=\frac{{V}_{in}M}{{L}_{f}}$  Yes 
LCCP [82,83,84,85]  ${f}_{o}=\frac{1}{2\pi \sqrt{{L}_{f}{C}_{f}}}=\frac{1}{2\pi \sqrt{{L}_{2}{C}_{2}}}=\frac{1}{2\pi \sqrt{{(L}_{1}{L}_{f}\frac{{M}^{2}}{{L}_{2}}}){C}_{1}}$ Resonant frequencycoupling dependent  CC  ${i}_{O}=\frac{{MV}_{in}}{{\omega}_{o}{{L}_{f}L}_{2}}$  Yes 
LCCLCC [86,87,88,89,90]  ${f}_{o}=\frac{1}{2\pi \sqrt{{L}_{f1}{C}_{f1}}}=\frac{1}{2\pi \sqrt{{L}_{f2}{C}_{f2}}}$ $=\frac{1}{2\pi \sqrt{{(L}_{1}{L}_{f1}){C}_{1}}}=\frac{1}{2\pi \sqrt{{(L}_{2}{L}_{f2}){C}_{2}}}$  CC  ${i}_{O}=\frac{{MV}_{in}}{{\omega}_{o}{{L}_{f1}L}_{f2}}$  Yes 
3.3. Hybrid Compensation Networks
4. Power Electronic Architectures and Control Methods
4.1. Auxiliary DCDC Converters
4.2. Phase Shift Angle Control
4.3. Frequency Modulation Control
4.4. Reconfigurable Hybrid Compensation
4.5. Switchable Dual Frequency
4.6. Tunable Compensation Networks
5. Discussion on LowVoltage and HighCurrent IPT Designs
6. Design Example for LowVoltage and HighCurrent IPT Applications
6.1. Coils Design
6.2. Proposed Asymmetric LCCLCC Compensation Network
DC and AC Conversion  Defined receiver equivalent impedances  

$\left\{\begin{array}{c}\begin{array}{c}{V}_{in}=\frac{2{\sqrt{2}V}_{dc}}{\pi};{V}_{O}=\frac{2{\sqrt{2}V}_{b}}{\pi}\\ {R}_{ac1}={R}_{ac2=}\frac{8\left(2{R}_{O}\right)}{{\pi}^{2}}\end{array}\\ {i}_{O1}={i}_{O2}=\frac{\pi}{2\sqrt{2}{(I}_{b}/2)}\end{array}\right.$  (5)  $\left\{\begin{array}{c}\begin{array}{c}{Z}_{eq1}=\frac{1/\left(j\omega {C}_{eq}\right)({R}_{ac1}+j\omega {L}_{fs1})}{1/(j\omega {C}_{eq}+{R}_{ac1}+j\omega {L}_{fs1})}\\ {Z}_{S1}=j\omega {L}_{2a}+\frac{1}{j\omega {C}_{s1}}+{Z}_{eq1}\end{array}\end{array}\right.$  (6) 
Defined transmitter equivalent impedances  Transmitter and receiver currents  
$\left\{\begin{array}{c}\begin{array}{c}{Z}_{ref1}=\frac{{\omega}^{2}{{M}_{1}}^{2}}{{Z}_{S1}}\\ {Z}_{p1}=j\omega {L}_{1}+\frac{1}{j\omega {C}_{1}}+{Z}_{ref1}\\ {Z}_{p2}=\frac{1/\left(j\omega {C}_{fp}\right){Z}_{p1}}{1/\left(j\omega {C}_{fp}\right)+{Z}_{p1}}\\ {Z}_{in1}=j\omega {L}_{fp}+{Z}_{p2}\end{array}\end{array}\right.$  (7)  $\left\{\begin{array}{c}\begin{array}{c}{I}_{in}=\frac{{V}_{in}}{{Z}_{in}};{I}_{1}=\frac{{I}_{in}{Z}_{p2}}{{Z}_{p1}}\\ {I}_{2}=\frac{j\omega {M}_{1}{I}_{1}}{{Z}_{S1}};{I}_{01}=\frac{{Z}_{eq1}{I}_{2}}{{R}_{ac1}+j\omega {L}_{fs1}}\end{array}\end{array}\right.$  (8) 
The current gain equation  Resonant conditions to obtain loadindependent current and ZPA  
${G}_{IV1}=\frac{{I}_{01}}{{V}_{in}}=\frac{{Z}_{eq1}j\omega {M}_{1}{Z}_{p2}}{{(R}_{ac1}+j\omega {L}_{fs1}){Z}_{S1}{Z}_{p1}{Z}_{in}}$  (9)  $\left\{\begin{array}{c}\begin{array}{c}\begin{array}{c}{C}_{P}={\left({{\omega}_{0}}^{2}\right({L}_{1}{L}_{fp}\left)\right)}^{1}\\ {C}_{S1}={\left({{\omega}_{0}}^{2}\right({L}_{2a}{L}_{fs1}\left)\right)}^{1}\\ {C}_{S2}={\left({{\omega}_{0}}^{2}\right({L}_{2b}{L}_{fs2}\left)\right)}^{1}\\ {C}_{fp}={\left({{\omega}_{0}}^{2}{L}_{fp}\right)}^{1}\\ {C}_{fs1}={\left({{\omega}_{0}}^{2}{L}_{fs1}\right)}^{1}\\ {C}_{fs2}={\left({{\omega}_{0}}^{2}{L}_{fs2}\right)}^{1}\end{array}\end{array}\end{array}\right.$  (10) 
$\mathrm{Transmitter}\mathrm{and}\mathrm{receiver}\mathrm{currents}\mathrm{at}\mathrm{the}\mathrm{resonant}\mathrm{frequency}{\mathit{\omega}}_{0}$  $\mathrm{Similarly}\mathrm{for}\mathrm{the}\mathrm{sec}\mathrm{ond}\mathrm{receiver}\mathrm{coil}\mathrm{side},\mathrm{the}\mathrm{coil}\mathrm{current}{\mathit{i}}_{3}$, $\mathrm{output}\mathrm{current}{\mathit{I}}_{\mathit{O}2}$ $\mathrm{and}\mathrm{total}\mathrm{output}\mathrm{current}{\mathit{i}}_{\mathit{O}}$  
$\left\{\begin{array}{c}\begin{array}{c}\begin{array}{c}\begin{array}{c}{i}_{in}=\frac{{M}_{1}{V}_{in}}{j{\omega}_{0}{L}_{fp}{L}_{fs1}}\hspace{1em}{i}_{1}=\frac{{V}_{in}}{j{\omega}_{0}{L}_{fp}}\\ {i}_{O1}=\frac{{M}_{1}{V}_{O}}{j{\omega}_{0}{L}_{fp}{L}_{fs1}}\hspace{1em}{i}_{2}=\frac{{V}_{O}}{j{\omega}_{0}{L}_{fs1}}\end{array}\end{array}\end{array}\end{array}\right.$  (11)  ${I}_{3}=\frac{{V}_{O}}{j{\omega}_{0}{L}_{fs2}}{;i}_{O2}=\frac{{M}_{2}{V}_{O}}{j{\omega}_{0}{L}_{fp}{L}_{fs2}}$ ${i}_{O}={i}_{O1}+{i}_{O2}$  (12) 
6.3. Proposed Passive Current Sharing Method of LCCLCC—BP Receiver Coil
6.4. Simulation Results
7. Discussion and Future Works
 For AGV applications, dynamic IPT solutions can be applied to reduce battery size, replace batteries with supercapacitors, or remove batteries entirely. Thus, vehicles can extend their operating time.
 Because of highcurrent stress on the receiver side. More studies into the circuit topologies, sensing techniques, and control methods of synchronous rectifiers is needed to improve the system’s efficiency.
 Wide BandGap (WBG) devices, such as GalliumNitride (GaN) semiconductors, can be used in highfrequency IPT for AGV applications, where the frequency can be increased to several hundreds of kHz or MHz to significantly reduce the volume of the coils and passive resonant components. Meanwhile, the frequency band for IPTLEVs remains limited by the SAE J2954 standard, recommended range of 81 kHz to 90 kHz.
 Experiment waveforms should be provided to validate the design concept through the implementation of hardware setups including DDBP coils, LCCLCC compensation, and HFinverter/rectifier.
 Although the proposed IPT design for loosely coupled LEVs applications has the advantage of a very low turnoff switching current as shown in simulation waveforms, the feasibility of the proposed methodology for tightly coupled AGV applications needs to be investigated further in future work.
8. Conclusions
Author Contributions
Funding
Data Availability Statement
Acknowledgments
Conflicts of Interest
Abbreviations
ACS  AC Switches  OBC  Onboard Charger 
AR  Active Rectifier  PP  ParallelParallel 
AWG  Americal Wire Gauge  PS  ParallelSeries 
AGV  Automated Guided Vehicles  PR  Passive Rectifier 
AMRs  Automated Mobile Robots  PE  Power Electronics 
BDD  Bipolar Double D  PFC  Power Factor Correction 
BP  Bipolar Pads  PWM  Pulse Width Modulation 
CPT  Capacitive Power Transfer  RX  Receiver 
CC  Constant Current  SBAR  SemiBridgeless Active Rectifier 
CP  Constant Power  SP  Series Parallel 
CV  Constant Voltage  SS  Series–Series 
CDR  Current Double Rectifiers  S/SP  Series/Series–Parallel 
CDSR  Current Double Synchronous Rectifier  SCCs  SwitchedControlled Capacitors 
DDQ  DDQuadrature  TX  Transmitter 
DOF  Degree of Freedom  UAV  Unmanned Air Vehicles 
DD  Double D  V2G  Vehicle to Grid 
EV  Electric Vehicles  WPT  Wireless Power Transfer 
ESR  Equivalent Series Resistance  ZCS  Zero Current Switching 
FHA  Fundamental Harmonic Approximation  ZPA  Zero Phase Angle 
G2V  Grid to Vehicle  ZVS  Zero Voltage Switching 
HFI  High Frequency Inverter  
IPT  Inductive Power Transfer  
ICE  Internal Combustion Engine  
ICCDR  Inverse Coupled Current Double Rectifier  
LEV  Light Electric Vehicles  
Liion  Lithium Ion  
MET  Maximum efficiency tracking 
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LEVs  Ref.  Motor (kW)  Battery Voltage (V)  Battery Capacity (kWh)  Range (km)  Max Speed (km/h)  Weight (kg)  Use  Country of Origin 

Citroen AMI  [19]  6  48  5.5  75  45  485  Urban mobility  France 
Renault Twizy  [20]  13  58  6.1  100  80  450  Urban mobility  France 
GEM e2  [21]  5  48  8.9  100  40  517  Urban mobility  USA 
EZGO Liberty  [22]  8.7  56.7  6.8  NA  31  408  Golf Cart  USA 
Italcarnev C2S.5  [23]  NA  48  NA  120  50  N/A  Urban mobility  Italy 
Italcar Attiva fleet.6  [23]  3  48  NA  36  22  N/A  Golf Cart  Italy 
Polaris Ranger EV  [24]  22  48  14.9  60–70  40  799  Offroad  USA 
Club Car Electric  [25]  2.4  48  NA  NA  30  410  Golf Cart  USA 
SolidHub GSE2500/5  [26]  11.5  48  34  N/A  15  4000  Forklift  UK 
Carver One  [27]  4  48  5,4  100  45.0  330.0  Urban mobility  Netherlands 
Microlino  [28]  12.5  N/A  14.0  230  90  530  Urban mobility  Switzerland 
Wuling Mini EV  [29]  20.0  90  9.2  120  100  665  Urban mobility  China 
Toyota C + Pod  [30]  9.2  177.6  9.1  150  60  680  Urban mobility  Japan 
Squad Mobility Solar  [31]  4.0  N/A  6.4  100  45  350  Urban mobility  Netherlands 
Tilting Triggo EV  [32]  15  48  14.0  140  90  530  Urban mobility  Poland 
Eli Zero  [33]  4.0  72  5.8  80  40  398  Urban mobility  USA 
Circular  Rectangular/Square  DD  DDQ  BP  

Number of coils  1  1  1  2  2 
Flux type  Single sided and unipolar  Single sided and unipolar  Single sided and bipolar  Double sided and bipolar  Double sided and bipolar 
Flux leakage  High  Moderate  Very low  Very low  Very low 
Transfer distance  Low  Low  Moderate  Large  Large 
Misalignment tolerance  Very poor  Poor  Good  Better  Better 
Interoperability  Poor  Poor  Good  Best  Best 
Charging area  Small  Small  Moderate  Large  Large 
Commonly used as  Tx/Rx  Tx/Rx  Tx  Rx  Rx 
ESR Losses  Small  Small  Medium  Large  Large 
Complexity  Very simple  Very simple  Simple  Complex  Moderate 
Reconfigurable Hybrid Topologies  Mode Selections  

CC Mode  CV Mode  
[65]  S1: ON and S2, S3: OFF SS ${i}_{O}=\frac{{V}_{in}}{{\omega}_{o}M}$ ZPA: Yes  S1: OFF and S2, S3: OFF PS with ${L}_{x}$ ${V}_{O}=\frac{{V}_{in}M}{{L}_{2}}$ ${(L}_{1}={L}_{x})$ ZPA: Yes 
[92]  S1: ON, S2: OFF SS ${i}_{O}=\frac{{V}_{in}}{{\omega}_{o}M}$ ZPA: Yes  S1: OFF, S2: ON SLCC ${V}_{O}=\frac{{V}_{in}{L}_{f}}{M}$ ZPA: Yes 
[93]  S1: OFF, S2: ON SS ${i}_{O}=\frac{{V}_{in}}{{\omega}_{o}M}$ ZPA: Yes  S1: ON, S2: OFF LCCS ${V}_{O}=\frac{{V}_{in}M}{{L}_{f}}$ ZPA: Yes 
[94]  S1: OFF, S2: ON LCCLCC ${i}_{O}=\frac{{MV}_{in}}{{\omega}_{o}{{L}_{f1}L}_{f2}}$ ZPA: Yes  S1: ON, S2: OFF LCCS ${V}_{O}=\frac{{V}_{in}M}{{L}_{f1}}$ ZPA: Yes 
[79]  S1: OFF, S2: ON SLCC+LCL ${I}_{O}=\frac{{V}_{in}{L}_{f}}{M{\omega}_{o}{L}_{T}}$ $({L}_{T1}={L}_{T2}={L}_{T})$ ZPA: Yes  S1: ON, S2: OFF SLCC ${V}_{O}=\frac{{V}_{in}{L}_{f}}{M}$ ZPA: Yes 
[95]  S1: OFF, S2: ON LCCS+LCL ${I}_{O}=\frac{M{V}_{in}}{{\omega}_{o}{{L}_{f}L}_{T}}$ $({L}_{T1}={L}_{T2}={L}_{T})$ ZPA: Yes  S1: ON, S2: OFF LCCS ${V}_{O}=\frac{{V}_{in}M}{{L}_{f}}$ ZPA: Yes 
Control Methodologies  Primary Side (HB, FB)  Secondary Side (AR, SemiR, PR)  Dual Side 

Frequency tuning  CP [97] MET [98] CC/CV [99]  N/A  N/A 
Phase shift control  CC/CV [100]  CC/CV [101,102]  CC/CV [103] CC/CV + MET [104] 
Auxiliary DCDC converter (Buck, Boost, BoostBuck)  CC/CV [105]  MET [106,107,108]  MET + CV [109,110,111] 
Switchable dualband frequency  CC/CV [89,90,112]  N/A  N/A 
Reconfigurable compensation networks  CC/CV [65,93]  CC/CV [79,87,92,94,95]  
Tunable compensation networks (Tunable equivalent capacitances or inductances)  MET [113,114] CC/CV [115,116]  CC/CV [117]  CC [118] CP [119] 
LEVs  AGVs  

Coupling coefficient k  Loosely coupling < 0.5  Tight coupling > 0.8 
Design challenges  
Highcurrent stress on rectifier devices  ✓  ✓ 
Large power losses on the receiver side  ✓  ✓ 
Require compact design  ✓  ✓ 
Sensitive to the air gap variation  ✓  
Highorder harmonic current  ✓ 
Ref. /Years  Applications  Coil StructuresTX/RX and Dimension  Resonant Topologies  Vin, P_{O}, V_{O}, I_{O},  Coupling k, f_{sw}, Efficiency  Circuit Structures and Design Objectives 

[123] 2019  AGV 
 LCCLCC 



[124] 2019  AGV 
 SS 



[126] 2022  LEV 
 LCCLCC 



[136] 2020  LEV 
 LCLS 



[122] 2022  AGV 
 SS 



[127] 2022  LEV, AGV 
 SS 



[135] 2022  LEV, AGV 
 LCCP 



[137] 2022  AGV 
 LCCLCC 



[138] 2022  AGV 
 Ttype/Series(T/S) 



Parameters  Symbols  Values 

Input voltage  V_{dc}  400 V 
Output voltage  V_{O}  48 V 
Output Power  P_{O}  2500 W 
Switching frequency  f_{O}  85 kHz 
Parameters  Value 

Coils dimension  400 × 400 mm 
TXDD coil ${L}_{1}$  235 uH 
RXBP coil ${L}_{2a},{L}_{2b}$  116 uH 
Mutual inductance ${M}_{12},{M}_{13}$  56 uH 
Overlap distance BP coil  121 mm 
Air gap distance  100 mm 
Ferrite bar pitch  26 mm 
Ferrite bar material  N87 
Litz wire  AWG38 × 300 strands 
Parameters  Values 

${C}_{P}$  27.32 nF 
${C}_{fp}$  32.85 nF 
${L}_{fp}$  106 uH 
${L}_{fs1},{L}_{fs2}$  12.8 uH 
${C}_{fs1},{C}_{fs2}$  273.8 nF 
${C}_{s1},{C}_{s2}$  36.1 nF 
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© 2023 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).
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Tran, M.T.; Thekkan, S.; Polat, H.; Tran, D.D.; El Baghdadi, M.; Hegazy, O. Inductive Wireless Power Transfer Systems for LowVoltage and HighCurrent Electric Mobility Applications: Review and Design Example. Energies 2023, 16, 2953. https://doi.org/10.3390/en16072953
Tran MT, Thekkan S, Polat H, Tran DD, El Baghdadi M, Hegazy O. Inductive Wireless Power Transfer Systems for LowVoltage and HighCurrent Electric Mobility Applications: Review and Design Example. Energies. 2023; 16(7):2953. https://doi.org/10.3390/en16072953
Chicago/Turabian StyleTran, Manh Tuan, Sarath Thekkan, Hakan Polat, DaiDuong Tran, Mohamed El Baghdadi, and Omar Hegazy. 2023. "Inductive Wireless Power Transfer Systems for LowVoltage and HighCurrent Electric Mobility Applications: Review and Design Example" Energies 16, no. 7: 2953. https://doi.org/10.3390/en16072953