A Parameter Recognition Based Impedance Tuning Method for SS-Compensated Wireless Power Transfer Systems

This article presents a parameter recognition-based impedance tuning method for the impedance mismatch caused by capacitance drift and coil misalignment in series-series-compensated wireless power transfer (WPT) systems. First, a parameter recognition method is proposed to identify the unknown parameters of the resonant circuits by only...

An Improved Peak Voltage Calculation Method for Compensation Components in S-S and LCC-S Compensated Wireless Power Transfer Systems

The pursuit of battery charging technology for electric vehicle (EV) has led to extensive research on the inductive-based wireless power transfer (WPT) systems. In this paper, the compensation component (including coils) stresses will be studied in two commonly adopted compensation topologies, namely S-S and LCC-S compensations. Due to the peak...

Design of a Highly Efficient 20 kW Inductive Power Transfer System with Improved Misalignment Performance

Due to the urgent desire for a fast, convenient, and efficient battery charging technology for electric vehicle (EV) users, extensive research has been conducted into the design of high-power inductive power transfer (IPT) systems. However, there are few studies that formulate the design as a multiobjective optimization (MOO) research...

Coils’ Current Distortion Due to Variable Series Compensation Capacitance in EV Wireless Charging for a Constant Optimum Load

When considering EV wireless charging that uses inductive power transfer with magnetic resonance, the coils’ current distortion must be minimized to guarantee compliance with the electromagnetic compatibility limits on the radiated magnetic field set by the relevant industrial standards. This paper analyzes the current distortion caused by...

Study on Soft Start-Up and Shut-Down Methods for Wireless Power Transfer Systems for the Charging of Electric Vehicles

The increase in popularity of electric vehicles (EVs) and the pursuit of user convenience makes wireless power transfer (WPT) an attractive technology for the charging of batteries. The usage of WPT in e-transportation is not straightforward because the current standardization limits the allowed operating frequency range and magnitude of the...

Analysis of Dynamic Charging Performances of Optimized Inductive Power Transfer Couplers

This paper aims to investigate the dynamic charging performance of an 11 kW dynamic inductive power transfer (DIPT) system. First, a multi-objective optimization (MOO) method is proposed to find the Pareto front of the DD charging pad. Then, the optimal design with a 96.82% efficiency is selected as the target design for the DIPT system....

Quality factor based design guideline for optimized inductive power transfer

In high-power wireless battery charging that uses inductive power transfer, a considerable amount of power losses are located in the transmitter and receiver coils because they carry high resonant currents and typically have a loose coupling between them which increases eddy current losses. Therefore, the nominal operation needs to be chosen...

Analysis of Magnetic Field Emissions in Inductive Power Transfer EV Chargers Following Reference Designs in SAE J2954/2019

This paper aims to investigate the radiated magnetic field by 11 kW inductive power transfer (IPT) systems used for the charging of electric vehicles. Two reference designs suggested by SAE J2954 are studied. Both designs are analysed to obtain the coils winding currents, and 3D FEM models are built in COMSOL without considering the car chassis,...

Electric Vehicle Charging Based on Inductive Power Transfer Employing Variable Compensation Capacitance for Optimum Load Matching

In inductive power transfer applications, it is possible to ensure high efficiency of the main coils by operating at the optimum load. Since the optimum load depends on the coupling between the main coils, the operation needs to be adapted to match this case at different alignment conditions. This paper proposes a method to keep the optimum load...

Compensation Network for a 7.7 kW Wireless Charging System that Uses Standardized Coils

Industrial wireless charging systems use standardized coils to guarantee interoperability between different manufacturers. In combination with these coils, the compensation network can still be designed and optimized. This paper explains the step-by-step design of the compensation network for a 7.7 kW wireless charging system (power class WPT2),...

Detection of Metallic Foreign Objects and Electric Vehicles Using Auxiliary Coil Sets for Dynamic Inductive Power Transfer Systems

This paper proposes a new method of electric vehicles detection (EVD) and foreign objects detection (FOD) for dynamic inductive power transfer (DIPT) systems. The proposed detection method applies both passive coil sets (PCSs) and active coil sets (ACSs) to achieve both EVD and FOD with a high detection sensitivity. The operation mechanisms...

Comparative Study of Foreign Object and Misalignment in Inductive Power Transfer Systems

This paper aims to identify the difference between foreign object (FO) and misalignment in terms of their influence on inductive power transfer (IPT) systems. This is performed through magnetic and equivalent circuit analysis of the mutual inductance, primary input impedance, charging pad terminal impedance and current harmonics. Experiment...

Survey on Standards and Regulations for Wireless Charging of Electric Vehicles

In the next decades, the number of electric vehicles (EVs) for private use is predicted to increase considerably. Charging the EVs through wireless power transfer (WPT), i.e. wireless charging, has the potential to shorten charging duration of EVs batteries through dynamic charging and it would also improve the safety of static charging in case...