Query: Modular-based inductive power transfer system for high-power applications

Candidate papers:

abstract: Although the demand for high power inductive power transfer (IPT) systems is on the rise, implementation of such IPT systems using low cost semiconductor devices has been a challenge. This study presents a new IPT topology that facilitates easy integration of multiple IPT modules, which are made of low cost and freely available semiconductor components, to cater for high power applications. An intermediate circuit, comprising an inductor capacitor inductor resonant network, serves as a contactless interface through which the modules of primary and secondary (pick up) systems can be either series or parallel integrated. Inductor coils of the intermediate circuit and both primary and pick up systems are magnetically coupled to allow for contactless power transfer. The proposed topology is parallel compensated to minimise its var requirement, and both the direction and amount of power flow are controlled by phase and/or magnitude modulation of voltages generated by primary and pick up side converters. Theoretical analysis, together with simulations and experimental evidence of integrating four prototype bi directional IPT systems to cater for 1.8 kW demand, is presented to show that the proposed new IPT topology is suitable for high power applications, and flexible for both bi directional and uni directional contactless power transfer.
author_names: Udaya K Madawala

Duleepa J Thrimawithana
title: Modular based inductive power transfer system for high power applications
year: 2012

abstract: The inductive power transfer (IPT) technology is gaining more and more attentions due to its convenience and safety. Because of the current limitation of commercial power electronic devices, the modular parallel technology has been adopted in high power IPT applications. The topologies based on the parallel voltage or current sources are proposed in recent researches. However, these topologies do not have the ability of modular switching due to the coupling of the module impedance. When the number of active modules decreases, the device stress of remaining active modules increases, which reduces the reliability of the IPT systems. To solve the problem, this paper proposes a new parallel topology for modular IPT systems. The device stress in active modules remains unchanged when modules are switched off. A 4.8kW IPT system with three modules is built to verify the decoupling characteristic of proposed parallel topology. The experimental result shows good agreement with the theoretical analysis.
author_names: Hongsheng Hu

Tao Cai

Shanxu Duan

Xiaoming Zhang

Jintao Niu

Hao Feng
title: A Parallel Topology for Modularized IPT Systems
venue: 2019 IEEE Energy Conversion Congress and Exposition (ECCE)
year: 2019

abstract: Mask aligner lithography is a technology used to transfer patterns with critical dimensions in the micrometer range from below 1 micron for contact printing to a dozen of microns in proximity printing. This technology is widely used in the fabrication of MEMS, micro optical components, and similar fields. Traditionally, the light sources used for mask aligners are high pressure mercury arc lamps, which emit in the UV rang of the spectrum with peaks at 365 nm, 405 nm and 435 nm, respectively the g h and i lines. These lamps suffer from several disadvantages (inefficient, bulky, dangerous) which makes alternatives interesting. In recent years, high power UV LEDs at the same wavelengths appeared on the market, opening the door to new illumination systems for mask aligners. We have developed a modular 250 W LED based illumination system, which can advantageously replace a 1 kW mercury arc lamp illumination. LEDs, arranged in a 7x7 grid array, are placed in the entrance apertures of individual reflectors, which collimate the individual irradiation to an output angle of 10deg. A subsequent fly's eye integrator homogenizes the illumination in the mask plane. It is followed by a Fourier lens, superimposing the individual channels in the mask plane, and a field lens to ensure telecentric illumination. This multisource approach allows the shaping of the source by switching individual illumination channels, determining the illumination angles and the spatial coherence in the mask plane. This concept can be used, for example, to do source mask optimization. Compared to mercury arc lamp illumination, our system is simultaneously more efficient, compact, versatile, economic and sustainable. In our contribution, we present the design of the system as well as lithographic test prints done with different illumination patterns.
author_names: Johana Bernasconi

Toralf Scharf

M Groccia

Raoul Kirner

Wilfried Noell

Hans Peter Herzig
title: High power modular LED based illumination system for lithography applications
venue: Optical Engineering Applications
year: 2018

abstract: It's very important to maintain the inverter zero voltage switching(ZVS) for inductive power transfer (IPT) system, especially for those high power applications. The ZVS condition can be obtained via regulating the inverter operating frequency of the IPT system. A modeling method based on the energy amplitude and phase is proposed and corresponding controller is designed to maintain the inverter ZVS condition for IPT. The dynamic model of the ZVS for the half bridge inverter is developed firstly. To facilitate the dynamic performance analysis and controller design, the original time variant model is linearized with small signal method at its operating point, which yields to a 4 order transfer function model. A PI controller which maintains ZVS condition via regulating the inverter operating frequency is designed based on the transfer function. An IPT prototype is built to verify the proposed theory. Experiments show that the controller traces the reference of the ZVS angle within 20 ms under various perturbation, which verifies the correction and effectiveness of the model and controller.
author_names: Jiangtao Liu

Qijun Deng

Wenbin Wang

Zhifan Li
title: Modeling and Control of Inverter Zero Voltage Switching for Inductive Power Transfer System
venue: IEEE Access
year: 2019

abstract: A DESIGN OF INDUCTIVE COUPLING WIRELESS POWER TRANSFER SYSTEM FOR ELECTRIC VEHICLE APPLICATIONS Daida Sarika Reddy Old Dominion University, 2019 Director: Dr. Yucheng Zhang This research focuses on the study of using an inductive coupled Wireless Power Transfer (WPT) system for electric vehicle charging applications in Medium Voltage DC (MVDC) power networks. Implementing WPT in Electric Vehicles (EVs) can provide a convenient alternative charging option, versus static charging in a station that would take hours. Also, it can prevent the potential of electrocution hazards that might occur due to the usage of physical medium like wires in EV charging. Even though inductive coupling has been applied in some applications of WPT, it is still not efficient enough to transfer high power at the kilowatts level due to weak coupling between the transmitter and the receiver. Using optimally specified resonant circuits along with inductive coupling can enhance the coupling and make the system more efficient for practical applications. This research aims to design and analyze the performance of a 5 KW WPT circuit. The optimal specification of a resonant circuit is studied and discussed. Theoretical calculations are performed to find the component values in the circuit to reach. The WPT system is firstly verified by performing simulation tests in the MATLAB/SIMULINK environment and then on a low power hardware testbed.
author_names: Sarika Reddy Daida
title: A Design of Inductive Coupling Wireless Power Transfer System for Electric Vehicle Applications
year: 2019

abstract: This paper proposes to use the double sided LC compensation circuit to realize the long distance and high power capacitive power transfer. The targeted transfer distance is 150mm for the vehicle charging application, resulting in a loosely coupled system. The circuit working principle and the transfer efficiency are provided, which indicates the duality with the conventional series series compensated inductive power transfer system. Using the same capacitive coupler, two load conditions (the constant resistive load and the constant voltage load)are analyzed for the practical applications. The analysis of the CPT system provides the guideline to design and optimize the LC compensated system. The experimental results show that kW level power transfer can be achieved through 150mm distance with dc dc efficiency from the dc source to the dc load to be around 88%
author_names: Hua Zhang

Chong Zhu

Fei Lu
title: Long Distance and High Power Capacitive Power Transfer based on the Double Sided LC Compensation: Analysis and Design
venue: 2019 IEEE Transportation Electrification Conference and Expo (ITEC)
year: 2019

abstract: This study proposed a hybrid inductive and capacitive wireless power transfer system to achieve high power transfer by combining inductive power transfer (IPT) and capacitive power transfer (CPT) A traditional IPT system imposes a high voltage on the transmitter because of resonance. Meanwhile, high voltages are required to establish an electric field to deliver power to the CPT system. Therefore, they can be combined to a hybrid system to achieve high power transfer by utilising two power transfer paths. A general model of the hybrid IPT and CPT coupler is analysed in detail. With a series series compensation topology, 1.1 kW hybrid system with equal power transferred by two paths is simulated and set up to evaluate the performance of the proposed method. An experimental prototype is built under various conditions, and the result shows that the hybrid system achieved 1.1 kW output power through both of magnetic path and of electric path successfully with 91.9% DC DC efficiency.
author_names: Bo Luo

Tao Long

Ruikun Mai

Ruimin Dai

Zhengyou He

Weihua Li
title: Analysis and design of hybrid inductive and capacitive wireless power transfer for high power applications
year: 2018

abstract: One of the most promising inductive power transfer applications is the wireless power supply for locomotives which may cancel the need for pantographs. In order to meet the dynamic and high power demands of wireless power supplies for locomotives, a relatively long transmitter track and multiple receivers are usually adopted. However, during the dynamic charging, the mutual inductances between the transmitter and receivers vary and the load of the locomotives also changes randomly, which dramatically affects the system efficiency. A maximum efficiency point tracking control scheme is proposed to improve the system efficiency against the variation of the load and the mutual inductances between the transmitter and receivers while considering the cross coupling between receivers. Firstly, a detailed theoretical analysis on dual receivers is carried out. Then a control scheme with three control loops is proposed to regulate the receiver currents to be the same, to regulate the output voltage and to search for the maximum efficiency point. Finally, a 2 kW prototype is established to validate the performance of the proposed method. The overall system efficiency (DC DC efficiency) reaches 90.6% at rated power and is improved by 5.8% with the proposed method under light load compared with the traditional constant output voltage control method.
author_names: Ruikun Mai

M C Linsen

Yeran Liu

Pengfei Yue

Guangzhong Cao

Zhengyou He
title: A Maximum Efficiency Point Tracking Control Scheme Based on Different Cross Coupling of Dual Receiver Inductive Power Transfer System
year: 2017

abstract: High power >50W) and high efficiency >90% wireless power transfer (WPT) systems are becoming in demand for portable electronic applications. In Fig. 8.2.1, power efficiency and/or output power specifications in prior art designs are much below the expected requirements [1 5] Frequency tuning in [1,2] is simple, but the switching frequency (fSW) deviates from 6.78MHz. Capacitor tuning [3,5] is the most intuitive approach, but the capacitor matrix occupies a large area, and the dynamically tuned compensation capacitor bank is limited by the digital control resolution and compensation accuracy. In addition, the duty cycle control in [4] leads to an unregulated output voltage at the RX side. Existing impedance matching techniques for reducing power loss are not applicable to high power impedance matching of a GaN based WPT system in the case of timevariable charging distance, loading, operation voltage, and temperature variations that induce a wide range of inductive or capacitive loading effects. Inductive loading degrades the efficiency by 51% in a GaN power switch and induces serious coupling effects to the gate of the GaN device due to the hard switching (HS) power loss. Likewise, capacitive loading results in the efficiency degradation of 14% due to the body diode conduction (BDC) power loss. Such large dissipation easily breakdowns a GaN device and even seriously damages the wPt system, especially when transmitting high power. Therefore, simultaneously achieving both (1) the minimized HS and BDC power loss by efficient impedance matching and (2) highly reliable operation of a GaN device over a wide range of loading effects is in urgent demand for high power and high efficiency WPT systems.
author_names: Che-Hao Yeh

Yen-Ting Lin

Chun-Chieh Kuo

Chao-Jen Huang

Cheng-Yu Xie

Shenting Lu

Wen-Hau Yang

Ke-Horng Chen

Kuo-Chi Liu

Ying-Hsi Lin
title: A 70W and 90% GaN based class E wireless power transfer system with automatic matching point search control for zero voltage switching and zero voltage derivative switching
venue: 2018 IEEE International Solid State Circuits Conference (ISSCC)
year: 2018

abstract: A multi transmitter configuration made by an array of passive resonant elements placed in the proximity of the driver coil for inductive Wireless Power Transfer applications is presented. The array is able to significantly decrease the electric field level produced by the fed loop at the operative frequency of 6 MHz, thus reducing the potentially dangerous radiation over biological tissues (i.e. the Specific Absorption Rate, SAR) Nonetheless, the proposed arrangement preserves the same efficiency level of the simple driver receiver system and it does not affect the useful working distance. Electromagnetic simulations have been performed to evaluate the SAR reduction and the efficiency levels achieved by the multi transmitter configuration in comparison with the driver receiver system. The proposed solution can be extremely useful in all the WPT applications in which the SAR exposure is a concern, such as automotive applications, biomedical implants and rechargeable devices.
author_names: Danilo Brizi

Nunzia Fontana

Sami Barmada

Agostino Monorchio
title: A Multi Transmitter Configuration for High Safety Wireless Power Transfer Applications
venue: 2019 International Applied Computational Electromagnetics Society Symposium (ACES)
year: 2019