We establish a theoretical bimodal model for the complex permeability of flaky soft magnetic composite materials to explain the variability of their initial permeability.The new model is motivated by finding the two n...We establish a theoretical bimodal model for the complex permeability of flaky soft magnetic composite materials to explain the variability of their initial permeability.The new model is motivated by finding the two natural resonance peaks to be inconsistent with the combination of the domain wall resonance and the natural resonance.In the derivation of the model,two relationships are explored:the first one is the relationship between the number of magnetic domains and the permeability,and the second one is the relationship between the natural resonance and the domain wall resonance.This reveals that the ball milling causes the number of magnetic domains to increase and the maximum initial permeability to exist after 10 h of ball milling.An experiment is conducted to demonstrate the reliability of the proposed model.The experimental results are in good agreement with the theoretical calculations.This new model is of great significance for studying the mechanism and applications of the resonance loss for soft magnetic composite materials in high frequency fields.展开更多
The complex interaction between material properties in an induction heating circuit was studied by multi physics simulation and by experimental verification in a full-scale laboratory heater. The work aims to illustra...The complex interaction between material properties in an induction heating circuit was studied by multi physics simulation and by experimental verification in a full-scale laboratory heater. The work aims to illustrate the complexity of the system of interacting materials, but also to propose a method to verify properties of soft magnetic composite materials in an integrated system and to identify which properties are the most critical under different circumstances and load cases. Heat losses at different loads were primarily studied, from DC currents to AC currents at 15, 20 and 25 kHz, respectively. A FE model for magnetic simulation was correlated with a corresponding model for heat simulation. The numerical model, as well as the established input material data, could be verified through the experimental measurements. In this particular study, the current loss in the litz wire was the dominant heat source, thus making the thermal conductivity of the SMC the most important property in this material.展开更多
Soft magnetic composite(SMC)material is an ideal soft magnetic material employed for developing 3D magnetic flux electromagnetic equipment,due to its advantages of 3D magnetic isotropy characteristic,low eddy current ...Soft magnetic composite(SMC)material is an ideal soft magnetic material employed for developing 3D magnetic flux electromagnetic equipment,due to its advantages of 3D magnetic isotropy characteristic,low eddy current loss,and simple manufacturing process.The permanent magnet claw pole machine(PMCPM)with SMC cores is a good case that the SMC to be adopted for developing 3D flux electrical machines.In this paper,a novel axial-radial flux permanent magnet claw pole machine(ARPMCPM)with SMC cores and ferrite magnets is proposed.Compared with the traditional PMCPM,the proposed ARPMCPM is designed with only one spoke PM rotor and its whole structure is quite compact.For the performance prediction,the 3D finite element method(FEM)is used.Meanwhile,for the performance evaluation,a previously developed axial flux claw pole permanent magnet machine(AFCPM)is employed as the benchmark machine and all these machines are optimized by using the combined multilevel robust Taguchi method.It can be seen that the proposed ARPMCPM is with higher torque/weight density and operation efficiency.展开更多
The performance of traditional flux switching permanent magnet tubular machine(FSPMTM)are improved by using new material and structure in this paper.The existing silicon steel sheet making for all mover cores or part ...The performance of traditional flux switching permanent magnet tubular machine(FSPMTM)are improved by using new material and structure in this paper.The existing silicon steel sheet making for all mover cores or part of stator cores are replaced by soft magnetic composite(SMC)cores,and the lamination direction of the silicon steel sheet in stator cores have be changed.The eddy current loss of the machine with hybrid cores will be reduced greatly as the magnetic flux will not pass through the silicon steel sheet vertically.In order to reduce the influence of end effect,the unequal stator width design method is proposed.With the new design,the symmetry of the permanent magnet flux linkage has been improved greatly and the cogging force caused by the end effect has been reduced.Both 2-D and 3-D finite element methods(FEM)are applied for the quantitative analysis.展开更多
Permanent magnet claw pole machine(PMCPM) is a special kind of transverse flux permanent magnet machine. Compared with other electrical machines, it has the advantages of high torque density and high efficiency for hi...Permanent magnet claw pole machine(PMCPM) is a special kind of transverse flux permanent magnet machine. Compared with other electrical machines, it has the advantages of high torque density and high efficiency for high speed operation. However, because of its complex irregular structure, the manufacturing process using silicon sheets is complicated. Soft magnetic composite material(SMC) is manufactured by powder metallurgy technology, which can produce various shapes of stator core structures, so it is easier to produce various irregular shapes of the stator core. However, the raw SMC material is relatively expensive, and the mechanical strength of SMC is weak. In this paper, a PMCPM with hybrid cores is proposed. With the adoption of hybrid silicon sheet-SMC cores and amorphous alloy-SMC cores, the torque ability of PMCPM can be improved greatly and it can have higher efficiency for more wide operation frequency. Meanwhile, its mechanical strength has been improved and it can be designed for high torque direct drive applications as it is a modular machine. Furthermore, three methods are proposed to reduce the additional eddy current loss which resulted from the employment of hybrid cores in PMCPM.展开更多
A new method of depositing an insulating multifunctional oxide coating on metal particles was developed.Such coatings increase corrosion resistance and insulate metal particles from each other.On base of capsulated by...A new method of depositing an insulating multifunctional oxide coating on metal particles was developed.Such coatings increase corrosion resistance and insulate metal particles from each other.On base of capsulated by oxide coating water-atomized iron powder ASC100.29,new composite soft magnetic materials were synthesized,which are able of replacing electrical steel in devices.Structural,electromagnetic properties and corrosion characte-ristics of the obtained composites were studied.It was found that the synthesized composite materials have low elec-tromagnetic losses,high values of magnetic induction(up to 2.1 T)and good corrosion resistance.The results demon-strate that the use of such materials in power supplies,c hokes,transformers,stators and rotors of electric machines and other products ensures their stable operation under various conditions.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11564024,51731001,and 11574122)the Fundamental Research Funds for the Central Universities,China(Grant No.lzujbky-2019-kb06).
文摘We establish a theoretical bimodal model for the complex permeability of flaky soft magnetic composite materials to explain the variability of their initial permeability.The new model is motivated by finding the two natural resonance peaks to be inconsistent with the combination of the domain wall resonance and the natural resonance.In the derivation of the model,two relationships are explored:the first one is the relationship between the number of magnetic domains and the permeability,and the second one is the relationship between the natural resonance and the domain wall resonance.This reveals that the ball milling causes the number of magnetic domains to increase and the maximum initial permeability to exist after 10 h of ball milling.An experiment is conducted to demonstrate the reliability of the proposed model.The experimental results are in good agreement with the theoretical calculations.This new model is of great significance for studying the mechanism and applications of the resonance loss for soft magnetic composite materials in high frequency fields.
文摘The complex interaction between material properties in an induction heating circuit was studied by multi physics simulation and by experimental verification in a full-scale laboratory heater. The work aims to illustrate the complexity of the system of interacting materials, but also to propose a method to verify properties of soft magnetic composite materials in an integrated system and to identify which properties are the most critical under different circumstances and load cases. Heat losses at different loads were primarily studied, from DC currents to AC currents at 15, 20 and 25 kHz, respectively. A FE model for magnetic simulation was correlated with a corresponding model for heat simulation. The numerical model, as well as the established input material data, could be verified through the experimental measurements. In this particular study, the current loss in the litz wire was the dominant heat source, thus making the thermal conductivity of the SMC the most important property in this material.
基金supported by the National Natural Science Foundation of China under project 52007047in part by the Outstanding Youth Innovation Project funded by State Key Laboratory of Reliability and Intelligence of Electrical Equipment EERI_OY2021005,and EERI_KF2021014。
文摘Soft magnetic composite(SMC)material is an ideal soft magnetic material employed for developing 3D magnetic flux electromagnetic equipment,due to its advantages of 3D magnetic isotropy characteristic,low eddy current loss,and simple manufacturing process.The permanent magnet claw pole machine(PMCPM)with SMC cores is a good case that the SMC to be adopted for developing 3D flux electrical machines.In this paper,a novel axial-radial flux permanent magnet claw pole machine(ARPMCPM)with SMC cores and ferrite magnets is proposed.Compared with the traditional PMCPM,the proposed ARPMCPM is designed with only one spoke PM rotor and its whole structure is quite compact.For the performance prediction,the 3D finite element method(FEM)is used.Meanwhile,for the performance evaluation,a previously developed axial flux claw pole permanent magnet machine(AFCPM)is employed as the benchmark machine and all these machines are optimized by using the combined multilevel robust Taguchi method.It can be seen that the proposed ARPMCPM is with higher torque/weight density and operation efficiency.
基金This work was supported in part by the National Natural Science Foundation of China under project 51877065Hebei Province Education Department Youth Talent Leading Project under grant BJ2018037in part by the State Key Laboratory of Reliability and Intelligence of Electrical Equipment under grant EERIKF2018005.
文摘The performance of traditional flux switching permanent magnet tubular machine(FSPMTM)are improved by using new material and structure in this paper.The existing silicon steel sheet making for all mover cores or part of stator cores are replaced by soft magnetic composite(SMC)cores,and the lamination direction of the silicon steel sheet in stator cores have be changed.The eddy current loss of the machine with hybrid cores will be reduced greatly as the magnetic flux will not pass through the silicon steel sheet vertically.In order to reduce the influence of end effect,the unequal stator width design method is proposed.With the new design,the symmetry of the permanent magnet flux linkage has been improved greatly and the cogging force caused by the end effect has been reduced.Both 2-D and 3-D finite element methods(FEM)are applied for the quantitative analysis.
基金supported by the National Natural Science Foundation of China under project 52007047the Outstanding Youth Innovation Project funded by State Key Laboratory of Reliability and Intelligence of Electrical Equipment EERI_OY2021005。
文摘Permanent magnet claw pole machine(PMCPM) is a special kind of transverse flux permanent magnet machine. Compared with other electrical machines, it has the advantages of high torque density and high efficiency for high speed operation. However, because of its complex irregular structure, the manufacturing process using silicon sheets is complicated. Soft magnetic composite material(SMC) is manufactured by powder metallurgy technology, which can produce various shapes of stator core structures, so it is easier to produce various irregular shapes of the stator core. However, the raw SMC material is relatively expensive, and the mechanical strength of SMC is weak. In this paper, a PMCPM with hybrid cores is proposed. With the adoption of hybrid silicon sheet-SMC cores and amorphous alloy-SMC cores, the torque ability of PMCPM can be improved greatly and it can have higher efficiency for more wide operation frequency. Meanwhile, its mechanical strength has been improved and it can be designed for high torque direct drive applications as it is a modular machine. Furthermore, three methods are proposed to reduce the additional eddy current loss which resulted from the employment of hybrid cores in PMCPM.
基金Supported by the Joint Projects of the Belarusian Republican Foundation for Basic Research and Romanian Academy(BRFBR-RA)(Nos.T19UZBG-004/2019,T20RA-004/2020).
文摘A new method of depositing an insulating multifunctional oxide coating on metal particles was developed.Such coatings increase corrosion resistance and insulate metal particles from each other.On base of capsulated by oxide coating water-atomized iron powder ASC100.29,new composite soft magnetic materials were synthesized,which are able of replacing electrical steel in devices.Structural,electromagnetic properties and corrosion characte-ristics of the obtained composites were studied.It was found that the synthesized composite materials have low elec-tromagnetic losses,high values of magnetic induction(up to 2.1 T)and good corrosion resistance.The results demon-strate that the use of such materials in power supplies,c hokes,transformers,stators and rotors of electric machines and other products ensures their stable operation under various conditions.