"Abstract—The operation of traditional rectifiers such as halfwave and bridge rectifiers in wireless power transfer applications may be inefficient and can reduce the amount of power that is delivered to a load. An alternative is to... more
"Abstract—The operation of traditional rectifiers such as halfwave
and bridge rectifiers in wireless power transfer applications
may be inefficient and can reduce the amount of power that is
delivered to a load. An alternative is to use Class E resonant
rectifiers which are known to operate efficiently at high resonant
frequencies and at large input voltages. Class E rectifiers have a
near sinusoidal input current which leads to an improved overall
system performance and increased efficiency, especially that of
the transmitting coil driver. This paper is the first to investigate
the use of Class E resonant rectifiers in wireless power transfer
systems based on resonant inductive coupling. A piecewise linear
state-space representation is used to model the Class E rectifier
including the rectifying diode’s forward voltage drop, its ON
resistance and the equivalent series resistance of the resonant
inductor. Power quality parameters, such as power factor and
total harmonic distortion, are calculated for different loading
conditions. Extensive experimental results based on a 10 W
prototype are presented to confirm the performed analysis and
the efficient operation of the rectifier. An impressive operating
efficiency of 94:43 % has been achieved at a resonant frequency
of 800 kHz."
In this paper, an inductive power transfer (IPT) system with four various resonance topologies were actively researched: series-series, series-parallel, series-parallel-series and dual side LCC. The aims of the study are... more
In this paper, an inductive power transfer (IPT) system with four various resonance topologies were actively researched: series-series, series-parallel, series-parallel-series and dual side LCC. The aims of the study are analyzing and comparison of these topologies in order to facilitate of choosing a suitable resonant circuit for a specific application of an IPT system. The considered criteria of analysis and comparison were: input impedance, suitability for small/large air-gap, ability to supply low/high load voltage, voltage gain, sensitivity to a misalignment, and activity at low/high frequency. Due to its high magnetic coupling, square coils were used in the transmitter and receiver sides.
Wireless charging is a technology of transmitting power through an air gap to electrical devices for the purpose of energy replenishment. The recent progress in wireless charging techniques and development of commercial products have... more
Wireless charging is a technology of transmitting power through an air gap to electrical devices for the purpose of energy replenishment. The recent progress in wireless charging techniques and development of commercial products have provided a promising alternative way to address the energy bottleneck of conventionally portable battery-powered devices. However, the incorporation of wireless charging into the existing wireless communication systems also brings along a series of challenging issues with regard to implementation, scheduling, and power management. In this article, we present a comprehensive overview of wireless charging techniques, the developments in technical standards, and their recent advances in network applications. In particular, with regard to network applications, we review the static charger scheduling strategies, mobile charger dispatch strategies and wireless charger deployment strategies. Additionally, we discuss open issues and challenges in implementing wireless charging technologies. Finally, we envision some practical future network applications of wireless charging.
Wireless charging is a technique of transmitting power through an air gap to an electrical device for the purpose of energy replenishment. Recently, the wireless charging technology has been significantly advanced in terms of efficiency... more
Wireless charging is a technique of transmitting power through an air gap to an electrical device for the purpose of energy replenishment. Recently, the wireless charging technology has been significantly advanced in terms of efficiency and functionality. This article first presents an overview and fundamentals of wireless charging. We then provide the review of standards, i.e., Qi and Alliance for Wireless Power (A4WP), and highlight on their communication protocols. Next, we propose a novel concept of wireless charger networking which allows chargers to be connected to facilitate information collection and control. We demonstrate the application of the wireless charger network in user-charger assignment, which clearly shows the benefit in terms of reduced costs for users to identify the best chargers to replenish energy for their mobile devices.
The misalignment and displacement of inductively coupled coils in a wireless power transfer system (WPT) can degrade the power efficiency and limit the amount of power that can be transferred. Coil misalignment leads the primary coil... more
The misalignment and displacement of inductively coupled coils in a wireless power transfer system (WPT) can degrade the power efficiency and limit the amount of power that can be transferred. Coil misalignment leads the primary coil driver to operate in an untuned state which causes non-optimum switching operation and results in an increase in switching losses. This paper presents a novel method to electronically tune a Class E inverter used as a primary coil driver in an inductive WPT system to minimize the detrimental effects of misalignment between the inductively coupled coils which may occur during operation. The tuning method uses current controlled inductors (saturable reactors) and a variable switching frequency to achieve optimum switching conditions regardless of the misalignment. Mathematical analysis is performed on a Class E inverter based on an improved model of a resonant inductive link. Experimental results are presented to confirm the analysis approach and the suitability of the proposed tuning method.
"This paper investigates the performance of Class E inverters used in wireless power transfer applications based on resonant inductive coupling. The variations in the load and the distance between the coils cause Class E inverters to... more
"This paper investigates the performance of Class E
inverters used in wireless power transfer applications based on
resonant inductive coupling. The variations in the load and the
distance between the coils cause Class E inverters to operate under
nonoptimal switching conditions, which result in inefficient operation
and can lead to permanent damage to its switching transistor.
Therefore, a novel approach to tune Class E inverters electronically
is proposed. The tuning method relies on saturable reactors
to ensure that the inverter operates under optimal switching conditions
regardless of variations in the load and the distance between
the coils. In addition, a more accurate model of inductive links is
presented in order to provide a better understanding of the major
power losses in resonant inductive links. Experimental results are
presented to confirm the improved accuracy of the inductive link
model and the validity of the tuning method.
"
The patent landscape report named "USING PATSEER TO SEARCH & ANALYZE PATENTS ON INDUCTIVE CHARGING" take a look on Inductive charging from Intellectual property perspective more so from the Patenting activity happening within this... more
The patent landscape report named "USING PATSEER TO SEARCH & ANALYZE PATENTS ON INDUCTIVE CHARGING" take a look on Inductive charging from Intellectual property perspective more so from the Patenting activity happening within this technology. Using PatSeer as database a sequence of steps was used to create search query, results were classified around following three key areas: • Technologies • Hardware • Applications Apart from answers to questions like Filing trend, top companies, where research activities are happening; you will also find information on where are researching teams of key companies located and which hardware component are they focusing on etc.. Company spotlight on following 4 companies, primarily into inductive charging: • POWERMAT • MOJO MOBILITY • WITRICITY • POWERBYPROXI Detailed analysis of Inductive charging technology can be found here : http://patseer.com/2016/01/patent-landscape-report-on-inductive-charging/
