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The existing simultaneous wireless power (SWP) and information transfer can only achieve serial signal transmission and it is hard to decouple the power and signal transmission without the additional circuits. To solve these problems, a SWP and multibit signals transfer technology is proposed in this article. Based on the working principle of the hybrid modulation waves pulsewidth modulation control technology, the power and multibit signals are modulated into the system through the modulation waves with different frequencies. Therefore, the signal transmission no longer depends on the power transmission, and the signal transmission rate is multiplied through the realization of parallel signals transmission. Subsequently, the parameter selection criterion of the signal channel is given by analyzing the signal transmission rate and the interference between the power and signal transmission. Finally, the proposed technology is verified with experimental results. The experimental results demonstrate that the power and two-bit signals can be transmitted stably. Compared to the serial transmission, the band signal transmission rate is increased by two times. [ABSTRACT FROM AUTHOR]

For implantable medical devices, it is of paramount importance to ensure uninterrupted energy supply to different circuits and subcircuits. Instead of relying on battery stored energy, harvesting energy from the human body and any external environmental sources surrounding the human body ensures prolonged life of the implantable devices and comfort of the patients. In this article, we present existing issues and challenges related to the state-of-the-art solutions used for harvesting energy to power implantable devices. In addition, the details on existing energy storage technologies and various wireless power transfer techniques incorporating external or internal energy sources and sensors have been discussed. The authors have outlined the performance and power constraints of existing biomedical devices and provided a brief overview of various power architectures found in the literature. This survey has been conducted on existing implantable solutions in terms of output voltage, current, device dimension, application, generated power, energy density, and so on. Finally, the advantages and drawbacks of different solutions have been discussed and compared. Therefore, this article can be considered as an expedient reference for researchers conducting research in the field of energy scavenging, internal energy storage, wireless power transfer techniques, and power management of implantable medical devices. [ABSTRACT FROM AUTHOR]

Wireless rechargeable sensor networks (WRSNs) employ wireless charging transfer technology to provide dynamic energy replenishment for sensors. Previous related research considers enhancing the flexibility of WRSNs with the use of wireless charging vehicles (WCVs). Although this research prolongs network lifetime to some extent, there still exist two essential drawbacks: off-road limitation and traveling speed limitation. Benefiting from the intrinsic flexibility, high flight speed, low cost and small size, wireless charging drones (drones) have great potentials to be used to charge sensors in WRSNs. However, suffering from limited battery capacities, it is impossible to use drones for charging sensors in large WRSNs independently. To conquer the drawbacks of WCVs and drones, we propose a novel WRSN model which integrates WCVs, WCV-carried drones and independent drones to construct an efficient novel charging system. The proposed system, which aims to extend network lifetime and to minimize the time of charging scheduling on premise of satisfying charging requests with the cooperation of WCVs and drones. Thus, we develop a novel charging scheduling scheme, which divides the sensing region into three circular sub-regions for scheduling the WCVs or drones collaboratively. Sensor nodes located in the inner ring are charged by independent drones directly from the base station. Nodes located in the middle ring are charged by WCVs, while the outer ring charged by WCV-carried drones. Simulation results show that our scheduling scheme outperforms multiple WCVs which either employ temporal or distantial priority scheme and earliest-deadline first scheme with respect to the lifetime and network charging efficiency. [ABSTRACT FROM AUTHOR]

This article proposes an enhanced timely and robust constant current (CC) control for wireless in-flight charging systems. The challenge for practical wireless in-flight charging systems is to maintain a CC output for hovering drones under circumstances of the continuous variation of coupling effect, various charging power requirements, and the parameter shifting, which is nearly unexplored in previous studies on wireless power transfer technologies. In order to address the issue, this article adopts the online-trained radial basis function neural network (RBFNN) to ensure the expected CC output for battery charging, which aims to handle negative impacts of the continuously varied coupling effect, the disturbance of parameters, and the change of charging current. In this article, both simulated and experimental results are given to verify the effectiveness of the proposed control scheme, wherein the accuracy of the controlled output current is within 5% and the average response time is less than 100 ms. It shows that the proposed dynamic-balancing robust current control is an ideal technical solution for wireless in-flight charging of drones by means of remarkable characteristics of the adopted RBFNN-based controller, namely, the increased rapidity and the enhanced robustness. [ABSTRACT FROM AUTHOR]

An uninterruptable wireless power supply is developed for a left ventricular assist device (LVAD), which is an implanted, electrically driven centrifugal pump used to treat advanced heart failure pathologies. The LVADs are currently powered through a cable driveline (DL) that exits the patient's body through the skin. Here, an innovative uninterruptable power supply is presented, based on a hybrid wireless/wired architecture: the electric power of 10 W is transferred by the near field wireless power transfer technology operating at 300 kHz, from outside the human body to an implanted subcutaneous receiver, and then by an internal cable to the LVAD. A significant improvement of the subcutaneous receiver is here proposed, based on the integration in the receiving coil of a battery pack providing the following benefits: no-break power supply for the LVAD; peak load management; enhanced system reliability; elimination of DL infection; enhancement of patient's quality of life. The proposed system is first designed and optimized, then a demonstrator is made and tested in a laboratory using the latest LVAD generation. The measured coil currents are used as sources for dosimetric analysis to assess the compliance of the system with the electromagnetic field safety and thermal regulations. [ABSTRACT FROM AUTHOR]

In this paper, a novel wireless servo motor drive is proposed and implemented, which artfully integrates wireless power transfer into the dc servo motor drive to achieve wireless bidirectional servo motion. Prominently, there is no power converter or controller at the servo motor side to realize the bidirectional rotation, while the motor control is fully conducted at the transmitter side. The key is to adopt only one transmitter with LCL network to achieve power equalization of two receiver coils, hence realizing bidirectional motion. Meanwhile, the phase-shift control method is newly developed to perform the desired speed control at the transmitter side, without requiring any switched capacitor arrays. As a result, the proposed wireless bidirectional servo motor drive takes the definite advantages of electrocution free and totally sealable. Both calculation and experimental results are presented to validate the feasibility and controllability. For the prototype, the transmission distance can reach up to 130 mm and the transmission efficiency can be up to 85%. [ABSTRACT FROM AUTHOR]