Power Transfer Strategy Research Articles

Temporal Interference Wireless Power Transfer Strategy With Passive Flexible Electrode for Vagus Nerve Stimulation

Temporal Interference Wireless Power Transfer Strategy With Passive Flexible Electrode for Vagus Nerve Stimulation

Assisted Power Transfer for Voltage Balance of Bipolar DC MicroGrids Using Inactive Motor Drives

A voltage balancer remains a good solution of power transfer for bipolar dc grids, which, however, would increase the costs due to its requirement for additional hardware support. In this article, an auxiliary power transfer strategy is proposed by using the inactive motor drives affiliated with the bipolar dc grid. During idle periods of the motor drive, one inverter bridge arm is connected with the bipolar dc grid at their neutral points, allowing bidirectional power transfer between the upper and lower dc-bus sources. The proposed strategy share part of the voltage balancer's power transfer burden without requiring additional hardware and affecting the normal operations of the motor drive. In addition, its effectiveness is verified by experimental results on an interior permanent magnet synchronous motor drive, showing that the power flows among the upper and lower dc-bus power supplies are controlled effectively. Also, the active control of the dc-bus voltages could be achieved by modulation of the phase currents.

Wireless Power Transfer Strategies for Medical Implants: Focus on Robustness and EM Compatibility

In the recent past, we have experienced astonishing progress in mapping human body functionalities and interconnections, encouraging a holistic view of physiological processes and medical analysis. Similar advances are occurring in modeling and theoretically investigating the interaction between electromagnetic (EM) fields and living systems, opening more and more opportunities to turn bio-EM interactions into a concrete, viable approach to the treatment of a variety of diseases. We are now able to understand the physiological implications of a certain EM stimulation at very deep levels-to cell membranes and beyond-and to quantify with high accuracy EM power density, even for very microscopic scales of analysis. And we can infer from this information the possible consequences of EM stimulation in terms of macroscopic effects on the whole biological system.

Research on Throughout with SWIPT in Two-Way Relay System Under Power Splitting Receiver

We consider the Simultaneous Wireless Information and Power Transfer strategy optimization in the two-way transmission relay system under Power Splitting (PS) receiver. In such case, we propose two operational strategies for two-way transmission under PS receiver structure, (1) Delay-Limited-Relay strategy (PS-LDR) and (2) Delay-Tolerated-Relay strategy (PS-TDR). PS-LDR strategy is that both sending node and receiving node need synchronization of information transmission, so communication systems have higher Signal Noise Ratio (SNR) threshold for channels, or communication may break down. In order to explore the performance of PS-LDR strategy, we use outage probability to calculate the analytical expression of the actual maximum throughput (AMT). PS-TDR strategy allows that the information received by the receiving node delays with the information sent by the sending node. Communication system in PS-TDR strategy has lower SNR threshold than that in PS-LDR strategy. The analytical expression of the AMT is calculated by the ergodic capacity in PS-TDR strategy. The influences of system parameters on the optimal throughput in two strategies are discussed.

Simultaneous Wireless Information and Power Transfer Strategies in Relaying Network With Direct Link to Maximize Throughput

In this paper, we investigate the optimal throughput performance for simultaneous wireless information and power transfer relaying network in the presence of direct link between the source and the destination. By considering the direct link, system performance can be improved when the channel condition is good from source to destination. The cooperative network consists of a source, an amplify-and-forward relay, and a destination, where the relay harvests energy from the source and then uses the harvested energy to forward information to the destination. At the destination node, the signals from the direct link and relay are combined by the maximum ratio combining (MRC) method. The time switching (TS) relaying protocol is applied to enable energy harvesting and information processing simultaneously. At the same time, we made progress on analyzing the throughput of information transmission on the basis of the MRC method with power switching (PS) relaying protocol. Additionally, adaptive-MRC protocol is proposed based on the TS and PS relaying protocols, which can choose better mode to achieve the communication. The numerical analyses provide practical insights into the effect of various system parameters, such as energy harvesting time splitting ratio, source transmission rate, distance between nodes, and noise power at the destination and the relay.

Wireless Energy Harvesting Using Signals From Multiple Fading Channels

In this paper, we study the average, the probability density function, and the cumulative distribution function of the harvested power. The signals are transmitted from multiple sources. The channels are assumed to be either Rician fading or Gamma-shadowed Rician fading. The received signals are then harvested by using either a single harvester for simultaneous transmissions or multiple harvesters for transmissions at different frequencies, antennas or time slots. Both linear and nonlinear models for the energy harvester at the receiver are examined. Numerical results are presented to show that, when a large amount of harvested power is required, a single harvester or the linear range of a practical nonlinear harvester are more efficient, to avoid power outage. Further, the power transfer strategy can be optimized for fixed total power. Specifically, for Rayleigh fading, the optimal strategy is to put the total power at the source with the best channel condition and switch off all other sources, while for general Rician fading, the optimum magnitudes and phases of the transmitting waveforms depend on the channel parameters.

무선 전력 전송 센서 네트워크에서 다중 접속에 따른 정보 및 전력 전송 기법 연구

무선 전력 전송 센서 네트워크에서 다중 접속에 따른 정보 및 전력 전송 기법 연구

Performance Characterization of Machine-to-Machine Networks With Energy Harvesting and Social-Aware Relays

In this paper, we propose a large-scale machine-to-machine (M2M) network architecture that incorporates energy harvesting and social-aware relays. The relay is powered by harvesting radio frequency energy and adopts the simultaneous wireless information and power transfer strategy. For the social aspect, a relay is conversant with only some of the communities and will only assist the data transfer of conversant sources. Moreover, for the energy harvesting and social-aware relay that assists the cooperative transmission protocol, we propose two different relay selection strategies, that is, social-aware random relay selection and social-aware best relay selection . The outage probability and network throughput of the proposed protocols are derived in a closed form using the stochastic geometry model, where the multiple M2M transmitter-receiver pairs and relays form independent homogeneous Poisson point processes, respectively. By comparing with the situation without social awareness, we find that social awareness can improve performance in some situations. The theoretical analysis is validated by extensive simulations.