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...

A Dynamic Frequency Sweeping Based Parameter Estimation Method for Wireless Power Transfer

It is ideal for the wireless power transfer (WPT) systems to operate at the resonance state for better transmission performance. In practice, however, the parameters of the resonant circuits often deviate because of the capacitance drift and coil misalignment. To this end, this paper proposes a new parameter estimation method for the WPT systems...

Frequency Tracking Method and Compensation Parameters Optimization to Improve Capacitor Deviation Tolerance of the Wireless Power Transfer System

Compensation capacitors are naturally susceptible to manufacturing defects and aging effects, leading to the degraded performance of a wireless power transfer (WPT) system. This article focuses on the compensation parameters optimization during the design stage and control strategy during the operation phase to improve the inherent capacitor...

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...

A Mode-Switching Based Phase Shift Control for Optimized Efficiency and Wide ZVS Operations in Wireless Power Transfer Systems

This article proposes a mode-switching-based phase shift control (MS-PSC) for wireless power transfer (WPT) systems, which is able to achieve power regulation, load matching, and wide ZVS operations simultaneously without using additional dc-dc converters. Based on the mode transitions between the full-bridge, mixed-bridge, and half-bridge...

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...

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...

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),...

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...