Study on impedance matching and maximum wireless power transfer efficiency of circuits with resonant coupling based on simplified &lt;i&gt;S&lt;/i&gt;-matrix

An analytical model is proposed to calculate the performance on beam collecting efficiency (BCE) of transmitting arrays with excitation errors for microwave power transmission (MPT). Due to the inconsistent output of power amplifiers and the uncertainty of the joint loss of radio frequency (RF) device, the small perturbations will be brought into excitation amplitudes and phases, which will decrease the BCE. This analytical model involves the use of a Taylor series expansion to account for small perturbations in the excitation errors. The mathematical model between the statistical information of excitation perturbations and BCE is directly established. To fully prove the accuracy of the given model, numerous random samples will be used to compare the results of the proposed model and Monte Carlo simulation (MCS). Compared with the MCS, the proposed model does not require much-repeated calculation. The proposed method can be applied at the antenna design stage to effectively evaluate the effect of excitation perturbations on the BCE.

Section: Introductionmentioning

confidence: 99%

An analytical model of transmitting arrays with excitation perturbations for microwave power transmission

Zhang

Lou

Wang

et al. 2022

“…The mainstream approach for the design and analysis of load impedance has traditionally been based on equivalent circuit analysis [7][8][9][10][11][12][13]. In recent years, on the other hand, approaches to determine the optimal load impedance and maximum available efficiency using passive two-port network parameters have been studied [14][15][16][17][18][19]. The advantage of formulations based on passive two-port network parameters is that they can be applied regardless of circuit topology [15].…”

Section: Introductionmentioning

confidence: 99%

Load optimization factors for analyzing the efficiency of wireless power transfer systems using two-port network parameters

Narusue

Kawahara

Morikawa

2020

This paper models and analyzes the power efficiency of wireless power transfer systems with arbitrary load impedances using passive twoport network parameters. In this formulation, two novel indices-the load resistance optimization factor and the load reactance optimization factorare defined and introduced to indicate the deviation of the load resistance and load reactance from their optimal values. It is shown that the power efficiency of these systems can be formulated using only their k-Q product and the defined load optimization factors. Additionally, we show that the ratio of efficiency to maximum available efficiency can be characterized with one single complex factor. The proposed approach helps the quantitive interpretation of the efficiency deterioration by the difference between the load impedance and its optimal value.

“…The conventional transmitter and receiver are placed in unidirectional coaxial positions. Thus, the receiver is limited by both range and direction in this case [16,17,18,19,20,21,22]. Furthermore, power transfer efficiency (PTE) will decrease dramatically when there is a little angular misalignment for the planar receiver.…”

Section: Introductionmentioning

confidence: 99%

Omnidirectional wireless power transfer system with a multidirectional receiver inside a cubic transmitter

Wang

Deng

Luo

et al. 2020

Dramatic advancements have been witnessed for the magnetic resonant coupling wireless power transfer technology used in various portable electronic devices. A novel omnidirectional wireless power transfer system was proposed in this paper. Instead of conventional planar coils, a multidirectional receiver inside the transmitter was designed to receive the electromagnetic energy from all the directions. As expected, the finite element simulation results show that the distribution of magnetic field is uniform at different positions inside the transmitter. And the power transfer efficiency (PTE) of the newly designed system with the multidirectional receiver is obviously greater than that of the conventional system with the planar coil. Effects of the different receiver structural sizes on the system performance were discussed. PTE of the system becomes higher when the receiver is larger. Furthermore, PTE is insensitive to position and angular misalignment of the multidirectional receiver. The experimental measurments show that PTE of the system with the multidirectional receiver is 26% at the frequency of 6.78 MHz. The newly designed magnetic resonant coupling wireless power transfer system will be significative for the electronic devices indoor.