Single-Wire Electric-Field Coupling Power Transmission Using Nonlinear Parity-Time-Symmetric Model with Coupled-Mode Theory

Abstract

The output power and transmission efficiency of the traditional single-wire electric-field coupling power transmission (ECPT) system will drop sharply with the increase of the distance between transmitter and receiver, thus, in order to solve the above problem, in this paper, a new nonlinear parity-time (PT)-symmetric model for single-wire ECPT system based on coupled-mode theory (CMT) is proposed. The proposed model for single-wire ECPT system not only achieves constant output power but also obtains a high constant transmission efficiency against variable distance, and the steady-state characteristics of the single-wire ECPT system are analyzed. Based on the theoretical analysis and circuit simulation, it shows that the transmission efficiency with constant output power remains 60% over a transmission distance of approximately 34 m without the need for any tuning. Furthermore, the application of a nonlinear PT-symmetric circuit based on CMT enables robust electric power transfer to moving devices or vehicles.Energies 2018, 11, 532 2 of 10 frequency splitting and stability of ICPT [8][9][10]. In practical application, inductive wireless charging for electric vehicles, mobile robots, and implanted devices were studied [11][12][13]. Professor Marin of MIT (Massachusetts Institute of Technology) proposed a new MRWPT technology and published it in the magazine Science in 2007 [5]. Until now, great progress has been made in the modeling of the system, impedance matching, electromagnetic safety, and standard setting [14,15]; in the application, Haier developed the tailless television in 2010, the KAIST (Korea Advanced Institute of Science and Technology) established a 12-km demonstration route of dynamic power supply for electric vehicles in Gumi city, South Korea in 2015, and the company of Zhonghui Chuangzhi in China applied MRWPT technology to charge a mine equipment monitoring system. As early as 1964, Willian C. Brown of Raytheon succeeded in using the MWPT technology to power a helicopter platform [16]. Subsequently, many scientists continued to study this technology, however, the bottleneck of transmission efficiency higher than 10% cannot be broken through. The technology of LWPT is still in the experimental stage and has not been put into practical application, Japan started experimenting on LWPT in 1997 [17], and used laser energy to power robots, kites, and helicopters [7,18]; scientists from Germany and the United States conducted experiments about LWPT in succession [19,20]. The first two WPT technologies have more extensive application and development prospects since the transmission efficiency of the latter two kinds of WPT technology is very low and the sensitivity of the direction is extremely high. The transmission distance of inductively coupling WPT is relatively close, in the range of tens of centimeters, and the distance of magnetic resonant coupling WPT is relatively far, in the range of a few meters, while its output power is not high, only suitable for low-power applications, such as mobile pho...

Single-Wire Transmission Methods: Justification of a Single-Wire Resonant Power Transmission System

“…At the same time, since the system uses wireless communication, the transmitting power and distances over which power can be transmitted are not impressive, although these figures are higher than those of traditional wireless resonant systems. So, in [23], based on theoretical analysis and circuit simulation, the authors were able to demonstrate that transmission efficiency at a constant output power remained at the level of 60% at a transmission distance of 34 m. Additionally, two investigations with various Tesla transformer types were conducted in [22], the results of which were consistent with earlier theoretical research. The outcomes indicated that energy transmission over a distance of 2 m was possible with a power of 40 W and an efficiency of 66.7% in the first experiment, and energy transmission over a distance of 30 m with a power of 100 W and an efficiency of 10% was possible in the second experiment.…”

“…The obtained system is called a gle-wire power transfer (SWPT) system. For such a system, publications [22,23] desc a nonlinear spacetime symmetrical model based on the theory of coupled oscillation schematic diagram of a single-wire power transfer system is shown in Figure 4. The gram shows that a source, a transmitter, a receiver, and a load comprise the system.…”

Research and Application of Capacitive Power Transfer System: A Review

“…Based on coupled-mode theory, ref. [85] proposed a nonlinear isochronous symmetric model as shown in Figure 6. A high-time-symmetric model for the single-capacitor CPT system is achieved and constant transmission efficiency was obtained under the condition of variable transfer distance.…”

Circuit Model and Analysis of Multi-Load Wireless Power Transfer System Based on Parity-Time Symmetry

“…To verify the results of the above theoretical analysis, a circuit simulation model is built. A full-bridge inverter is used to construct a nonlinear saturation gain system instead of half-bridge inverter as [29,32] to achieve higher output power. The schematic diagram of the simulation circuit of the dual-load PT-WPT system is shown in Figure 9.…”