scholarly journals Ge Schottky diode for improving energy conversion efficiency of the receiver of microwave wireless power transfer

2020 ◽  
Vol 69 (10) ◽  
pp. 108401
Author(s):  
Yu-Chen Li ◽  
Hang-Yu Chen ◽  
Jian-Jun Song
Keyword(s):  
Energy Conversion ◽  
Conversion Efficiency ◽  
Schottky Diode ◽  
Wireless Power Transfer ◽  
Energy Conversion Efficiency ◽  
Power Transfer ◽  
Wireless Power

scholarly journals Wireless power transfer with transmit diversity

F1000Research ◽  
2021 ◽  
Vol 10 ◽  
pp. 916
Author(s):  
Yee-Loo Foo
Keyword(s):  
Energy Conversion ◽  
Conversion Efficiency ◽  
Transmit Diversity ◽  
Wireless Power Transfer ◽  
Energy Conversion Efficiency ◽  
Diversity Gain ◽  
Conversion Gain ◽  
Power Transfer ◽  
Wireless Power ◽  
Analytical Expression

Background: Wireless power transfer is important for energizing and recharging the Internet-of-Things (IoT) cordlessly. Harnessing energy effectively from radio waves has become a crucial task. It is known that diversities at the transmitting antenna and waves (i.e. simultaneous continuous waves with center frequencies separated apart) can enhance the radio frequency (RF) to direct current (DC) energy conversion. What remains unknown is the extent of which the wave diversity enhances the conversion gain. This study attempts to examine the RF-to-DC conversion gain of applying wave diversity. This paper investigates the effects of wave diversity on the energy conversion efficiency, and contributes the analytical expression that relate the conversion efficiency to the diversity count, i.e. the number of simultaneously transmitted sinewaves. Methods: We adopted a theoretical approach to the problem. First, we derived and presented a theoretical model that incorporated different forms of transmit diversity, i.e. antenna and wave diversities. This model then connected a RF-to-DC energy conversion model resulting from polynomial fitting on circuit simulation results. With the availability of these two models, we determined the theoretical energy conversion gain of simultaneously transmitting multiple sinewaves. Results: The results showed that transmitting multiple sinewaves simultaneously yields diversity gain and higher energy conversion efficiency. Most importantly, the gain and conversion efficiency can now be theoretically quantified. For example, at certain RF power measured at the receiver circuit, the diversity gain of transmitting four sinewaves is 2.6 (as compared to transmitting single sinewave). In fact, both the diversity gain and conversion efficiency increased with the number of simultaneously transmitted sinewaves. In another example, the conversion efficiency of transmitting four sinewaves is 0.1 as compared to 0.075 of two sinewaves. Conclusions: In summary, this paper presents a novel analytical expression for wave diversity in the context of wireless power transfer.

scholarly journals Zero Voltage Switching Condition in Class-E Inverter for Capacitive Wireless Power Transfer Applications

Energies ◽  
2021 ◽  
Vol 14 (4) ◽  
pp. 911
Author(s):  
Fabio Corti ◽  
Alberto Reatti ◽  
Ya-Hui Wu ◽  
Dariusz Czarkowski ◽  
Salvatore Musumeci
Keyword(s):  
Conversion Efficiency ◽  
Coupling Coefficient ◽  
Design Procedure ◽  
Wireless Power Transfer ◽  
Power Transfer ◽  
Wireless Power ◽  
Zero Voltage Switching ◽  
Zero Voltage ◽  
Voltage Switching ◽  
Class E

This paper presents a complete design methodology of a Class-E inverter for capacitive wireless power transfer (CWPT) applications, focusing on the capacitance coupling influence. The CWPT has been investigated in this paper, because most of the literature refers to inductive power transfer (IWPT). However, CWPT in perspective can result in lower cost and higher reliability than IWPT, because it does not need coils and related shields. The Class-E inverter has been selected, because it is a single switch inverter with a grounded MOSFET source terminal, and this leads to low costs and a simple control strategy. The presented design procedure ensures both zero voltage switching (ZVS) and zero derivative switching (ZDS) conditions at an optimum coupling coefficient, thus enabling a high transmission and conversion efficiency. The novelties of the proposed method are that the output power is boosted higher than in previous papers available in the literature, the inverter is operated at a high conversion efficiency, and the equivalent impedance of the capacitive wireless power transfer circuit to operate in resonance is exploited. The power and the efficiency have been increased by operating the inverter at 100 kHz so that turn-off losses, as well as losses in inductor and capacitors, are reduced. The closed-form expressions for all the Class-E inverter voltage and currents waveforms are derived, and this allows for the understanding of the effects of the coupling coefficient variations on ZVS and ZDS conditions. The analytical estimations are validated through several LTSpice simulations and experimental results. The converter circuit, used for the proposed analysis, has been designed and simulated, and a laboratory prototype has been experimentally tested. The experimental prototype can transfer 83.5 W at optimal capacitive coupling with operating at 100 kHz featuring 92.5% of the efficiency, confirming that theoretical and simulation results are in good agreement with the experimental tests.

Energy conversion efficiency in betavoltaic cells based on the diamond Schottky diode with a thin drift layer

2020 ◽  
Vol 157 ◽  
pp. 109017 ◽  
Author(s):  
V. Grushko ◽  
O. Beliuskina ◽  
A. Mamalis ◽  
V. Lysakovskiy ◽  
E. Mitskevich ◽  
...  
Keyword(s):  
Energy Conversion ◽  
Conversion Efficiency ◽  
Schottky Diode ◽  
Energy Conversion Efficiency ◽  
Drift Layer
Sign in / Sign up

Export Citation Format

Share Document