During wireless charging,misalignments commonly occur in the transmission between the transmitting and receiving pads,including misalignments in the forward,backward,lateral and vertical directions.Unavoidable misalig...During wireless charging,misalignments commonly occur in the transmission between the transmitting and receiving pads,including misalignments in the forward,backward,lateral and vertical directions.Unavoidable misalignments can result in changes in system parameters,thus affecting charging performance.A novel diagonally crossed solenoid magnetic coupler(DCSMC)is developed as a solution.The DCSMC integrated into a wireless power transfer(WPT)system with a hybrid topology enables superior misalignment tolerance in the X,Y,Zand XYdiagonal directionswhile maintaining load-independent voltage output characteristics.A simplified parameter design method is developed to optimize the misalignment tolerance performance of a hybrid WPT system in multiple directions.Finally,a hardware prototype of a WPT system is constructed with an operating frequency of 200kHz and a power of 200W.The experimental results showthat the hybrid WPT system,operating under loads from 40Ωto 80Ω,can tolerate misalignments of±90mm(40.9%)in both the Xand Yaxes,maintaining as small as a 5%fluctuation in output voltage.In addition,the WPT system can handle a maximum vertical displacement of+40mm along the Z-axis and XY-diagonal misalignments of±40mm(12.8%).展开更多
Fleets of autonomous vehicles including shuttle buses,freight trucks,and road sweepers will be deployed in the Olympic Vil-lage during Beijing 2022 Winter Olympics.This requires intelligent charging infrastructure bas...Fleets of autonomous vehicles including shuttle buses,freight trucks,and road sweepers will be deployed in the Olympic Vil-lage during Beijing 2022 Winter Olympics.This requires intelligent charging infrastructure based on wireless power transfer technology to be equipped.To increase the misalignment tolerance of a high-power wireless charger,the robustness of the magnetic coupler should be optimized.This paper presents a new type of unipolar coupler,which is composed of three con-nected coils in series.The dimensional configuration of the coils is analyzed by the finite element method.The characteristic parameters of the coil are identified with their influence on the self-inductance and coupling coefficient.An expert model is built,whose feasibility can be verified in the aimed design domain.Combined with the expert model,an improved simulated annealing algorithm with a backtracking mechanism is proposed.The primary coil can reach the expected characteristics from any starting parameter combination through the proposed optimization algorithm.Under the same conditions in terms of external circuit parameters,ferrite usage,and aluminum shielding,the offset sensitivity of the magnetic coupler can be reduced from 58.79%to 18.89%.A prototype is established,validating the feasibility of the proposed coil structure with the optimized parameter algorithm.展开更多
The demand for electric vehicles has increased over the past few years.Wireless power transfer for electric vehicles provides more flexibility than traditional plug-in charging technology.Charging couplers are critica...The demand for electric vehicles has increased over the past few years.Wireless power transfer for electric vehicles provides more flexibility than traditional plug-in charging technology.Charging couplers are critical components in wireless power transfer systems.The thermal effect produced by the magnetic coupler in work will cause the temperature of the device to rise rapidly,affecting the work efficiency,transfer power,operation reliability,and service life.This paper modeled and analyzed each component's temperature distribution characteristics and thermal behavior.Firstly,the magnetic coupler's mutual inductance and magnetic circuit model are established,and the thermal model of the magnetic coupler analyzes the heat generation process.The thermal models of the coupler under three different magnetic core distributions are established,and the temperature rise of each component is obtained.The temperature rise of different parts of the coupler is verified by the temperature rise test structure of the experiment.展开更多
The paper presents the results of an experimental study and numerical cakulations of torques in magnetic cou-plers of various configurations.A comparison was made for model couplers based on permanent magnets(PMG)and ...The paper presents the results of an experimental study and numerical cakulations of torques in magnetic cou-plers of various configurations.A comparison was made for model couplers based on permanent magnets(PMG)and couplers based on high-temperature superconducting(HTS)tapes cooled with liquid nitrogen.In PMG-couplers,both coupler halves are made of pemmanent magnets,while in HTS-couplers,one coupler half is axial and radial configurations,with different clearances between the coupler halves.The results of experimental made of HTS-tapes stacks,and the second of permanent magnets.Both types of couplers are considered in both studies showed that in the configurations we considered,radial HTS-co uplers are superior to their axialanalogues in termsof the maximum torque between the coupler halves.In addition,in the considered configurations,PMG couplers excceded their HTS analogues in torque by 10times.Numerical finite element calculations usinga com-bined A-T-H form ulation were used to optimize the design of the HTS-coupler.The model was verified using the obtained experimental data for moments in model couplers.The model was used to calculate an optimized cou-pler with added HTS-windings,lowerHTS temperature and strongerpermanent magnets.The calculation results showed that HTS-couplers can be comparable with their PMG analogues,at the same time they are significantly superior to them in damping external disturbances.Due to the fact that the best characteristics were shown by model radial couplers with m inimal gaps between the coupler halves,radial couplers were manufactured based on windings of 10 and 20 layers of HTS-tapes and the torques in them weremeasured in theFCandZFC modes.It has been shown that in most operating conditions,10-layer couplers outperform 20-layer couplers.展开更多
The permanent magnet eddy current coupler(PMEC)solves the problem of flexible connection and speed regulation between the motor and the load and is widely used in electrical transmission systems.It provides torque to ...The permanent magnet eddy current coupler(PMEC)solves the problem of flexible connection and speed regulation between the motor and the load and is widely used in electrical transmission systems.It provides torque to the load and generates heat and losses,reducing its energy transfer efficiency.This issue has become an obstacle for PMEC to develop toward a higher power.This paper aims to improve the overall performance of PMEC through multi-objective optimization methods.Firstly,a PMEC modeling method based on the Levenberg-Marquardt back propagation(LMBP)neural network is proposed,aiming at the characteristics of the complex input-output relationship and the strong nonlinearity of PMEC.Then,a novel competition mechanism-based multi-objective particle swarm optimization algorithm(NCMOPSO)is proposed to find the optimal structural parameters of PMEC.Chaotic search and mutation strategies are used to improve the original algorithm,which improves the shortcomings of multi-objective particle swarm optimization(MOPSO),which is too fast to converge into a global optimum,and balances the convergence and diversity of the algorithm.In order to verify the superiority and applicability of the proposed algorithm,it is compared with several popular multi-objective optimization algorithms.Applying them to the optimization model of PMEC,the results show that the proposed algorithm has better comprehensive performance.Finally,a finite element simulation model is established using the optimal structural parameters obtained by the proposed algorithm to verify the optimization results.Compared with the prototype,the optimized PMEC has reduced eddy current losses by 1.7812 kW,increased output torque by 658.5 N·m,and decreased costs by 13%,improving energy transfer efficiency.展开更多
基金Supported by the Guangdong Basic and Applied Basic Research Foundation(2023A1515240033)the Basic and Applied Basic Research Foundation of Guangzhou(2024A04J6540)the Natural Science Foundation for Distinguished Young Scholars of Guangdong Province(2022B1515020002).
文摘During wireless charging,misalignments commonly occur in the transmission between the transmitting and receiving pads,including misalignments in the forward,backward,lateral and vertical directions.Unavoidable misalignments can result in changes in system parameters,thus affecting charging performance.A novel diagonally crossed solenoid magnetic coupler(DCSMC)is developed as a solution.The DCSMC integrated into a wireless power transfer(WPT)system with a hybrid topology enables superior misalignment tolerance in the X,Y,Zand XYdiagonal directionswhile maintaining load-independent voltage output characteristics.A simplified parameter design method is developed to optimize the misalignment tolerance performance of a hybrid WPT system in multiple directions.Finally,a hardware prototype of a WPT system is constructed with an operating frequency of 200kHz and a power of 200W.The experimental results showthat the hybrid WPT system,operating under loads from 40Ωto 80Ω,can tolerate misalignments of±90mm(40.9%)in both the Xand Yaxes,maintaining as small as a 5%fluctuation in output voltage.In addition,the WPT system can handle a maximum vertical displacement of+40mm along the Z-axis and XY-diagonal misalignments of±40mm(12.8%).
基金This work was supported by the National Key Research and Development Program of China(No.2019YFE0104700)。
文摘Fleets of autonomous vehicles including shuttle buses,freight trucks,and road sweepers will be deployed in the Olympic Vil-lage during Beijing 2022 Winter Olympics.This requires intelligent charging infrastructure based on wireless power transfer technology to be equipped.To increase the misalignment tolerance of a high-power wireless charger,the robustness of the magnetic coupler should be optimized.This paper presents a new type of unipolar coupler,which is composed of three con-nected coils in series.The dimensional configuration of the coils is analyzed by the finite element method.The characteristic parameters of the coil are identified with their influence on the self-inductance and coupling coefficient.An expert model is built,whose feasibility can be verified in the aimed design domain.Combined with the expert model,an improved simulated annealing algorithm with a backtracking mechanism is proposed.The primary coil can reach the expected characteristics from any starting parameter combination through the proposed optimization algorithm.Under the same conditions in terms of external circuit parameters,ferrite usage,and aluminum shielding,the offset sensitivity of the magnetic coupler can be reduced from 58.79%to 18.89%.A prototype is established,validating the feasibility of the proposed coil structure with the optimized parameter algorithm.
文摘The demand for electric vehicles has increased over the past few years.Wireless power transfer for electric vehicles provides more flexibility than traditional plug-in charging technology.Charging couplers are critical components in wireless power transfer systems.The thermal effect produced by the magnetic coupler in work will cause the temperature of the device to rise rapidly,affecting the work efficiency,transfer power,operation reliability,and service life.This paper modeled and analyzed each component's temperature distribution characteristics and thermal behavior.Firstly,the magnetic coupler's mutual inductance and magnetic circuit model are established,and the thermal model of the magnetic coupler analyzes the heat generation process.The thermal models of the coupler under three different magnetic core distributions are established,and the temperature rise of each component is obtained.The temperature rise of different parts of the coupler is verified by the temperature rise test structure of the experiment.
基金The work was carried out under the State Assignment(project FSWU‐2022‐0013)with the support of the Ministry of ScienceHigher Education of the Russian Federation.
文摘The paper presents the results of an experimental study and numerical cakulations of torques in magnetic cou-plers of various configurations.A comparison was made for model couplers based on permanent magnets(PMG)and couplers based on high-temperature superconducting(HTS)tapes cooled with liquid nitrogen.In PMG-couplers,both coupler halves are made of pemmanent magnets,while in HTS-couplers,one coupler half is axial and radial configurations,with different clearances between the coupler halves.The results of experimental made of HTS-tapes stacks,and the second of permanent magnets.Both types of couplers are considered in both studies showed that in the configurations we considered,radial HTS-co uplers are superior to their axialanalogues in termsof the maximum torque between the coupler halves.In addition,in the considered configurations,PMG couplers excceded their HTS analogues in torque by 10times.Numerical finite element calculations usinga com-bined A-T-H form ulation were used to optimize the design of the HTS-coupler.The model was verified using the obtained experimental data for moments in model couplers.The model was used to calculate an optimized cou-pler with added HTS-windings,lowerHTS temperature and strongerpermanent magnets.The calculation results showed that HTS-couplers can be comparable with their PMG analogues,at the same time they are significantly superior to them in damping external disturbances.Due to the fact that the best characteristics were shown by model radial couplers with m inimal gaps between the coupler halves,radial couplers were manufactured based on windings of 10 and 20 layers of HTS-tapes and the torques in them weremeasured in theFCandZFC modes.It has been shown that in most operating conditions,10-layer couplers outperform 20-layer couplers.
基金supported by the National Natural Science Foundation of China under Grant 52077027.
文摘The permanent magnet eddy current coupler(PMEC)solves the problem of flexible connection and speed regulation between the motor and the load and is widely used in electrical transmission systems.It provides torque to the load and generates heat and losses,reducing its energy transfer efficiency.This issue has become an obstacle for PMEC to develop toward a higher power.This paper aims to improve the overall performance of PMEC through multi-objective optimization methods.Firstly,a PMEC modeling method based on the Levenberg-Marquardt back propagation(LMBP)neural network is proposed,aiming at the characteristics of the complex input-output relationship and the strong nonlinearity of PMEC.Then,a novel competition mechanism-based multi-objective particle swarm optimization algorithm(NCMOPSO)is proposed to find the optimal structural parameters of PMEC.Chaotic search and mutation strategies are used to improve the original algorithm,which improves the shortcomings of multi-objective particle swarm optimization(MOPSO),which is too fast to converge into a global optimum,and balances the convergence and diversity of the algorithm.In order to verify the superiority and applicability of the proposed algorithm,it is compared with several popular multi-objective optimization algorithms.Applying them to the optimization model of PMEC,the results show that the proposed algorithm has better comprehensive performance.Finally,a finite element simulation model is established using the optimal structural parameters obtained by the proposed algorithm to verify the optimization results.Compared with the prototype,the optimized PMEC has reduced eddy current losses by 1.7812 kW,increased output torque by 658.5 N·m,and decreased costs by 13%,improving energy transfer efficiency.
