Improved Square-Coil Configurations for Homogeneous Magnetic Field Generation

Homogeneous magnetic field is widely used in various applications, and Helmholtz and Merritt coils are the most commonly used homogeneous field generators. However, only the field homogeneity at the center point is concerned in their design, which leads to restriction for most applications, where a certain volume of homogeneous field is required. This indicates that traditional coil configurations can be further optimized. Based upon a comprehensive definition of homogeneous field, improved three-s and four-coil configurations are proposed in this article. Practical formulae with normalized coil parameters are given to provide a convenient tool for designers. These formulae establish relationships between coil parameters and the required homogeneous field. The accuracy of the formulae is verified by the finite-element analysis. Comparisons with Merritt coils show that, when getting the same homogeneous field, the improved coils can reduce both power loss and conductor mass by up to 24.8%. Through a comparison among main coil configurations, the improved four-coil configuration is recommended for homogeneous magnetic field generation. For high-intensity magnetic field applications, the winding cross-section effect is analyzed. At last, experiments are performed to verify the theoretical analysis, and the reason why the improved coils have better performance than traditional ones is revealed.

[1]  Yi Huang,et al.  Range-Adaptive Wireless Power Transfer Based on Differential Coupling Using Multiple Bidirectional Coils , 2020, IEEE Transactions on Industrial Electronics.

[2]  A. Sommers,et al.  Variations of the Static Contact Angle of Ferrofluid Droplets on Solid Horizontal Surfaces in External Uniform Magnetic Fields. , 2020, Langmuir : the ACS journal of surfaces and colloids.

[3]  Weiguo Li,et al.  A Load-Independent LCC-Compensated Wireless Power Transfer System for Multiple Loads With a Compact Coupler Design , 2020, IEEE Transactions on Industrial Electronics.

[4]  Donghua Pan,et al.  Research on the Design Method of Uniform Magnetic Field Coil Based on the MSR , 2020, IEEE Transactions on Industrial Electronics.

[5]  P. Zhang,et al.  The physics of helical electron beam in a uniform magnetic field as a testing ground of gauge principle , 2019, Physics Letters A.

[6]  Chaode Cen,et al.  Improving Magnetofection of Magnetic Polyethylenimine Nanoparticles into MG-63 Osteoblasts Using a Novel Uniform Magnetic Field , 2019, Nanoscale Research Letters.

[7]  Ming Zhang,et al.  An Improved Two-Coil Configuration for Low-Frequency Magnetic Field Immunity Tests and Its Field Inhomogeneity Analysis , 2018, IEEE Transactions on Industrial Electronics.

[8]  Alexander M. Trbovich,et al.  Design and Optimization of Electromagnets for Biomedical Experiments With Static Magnetic and ELF Electromagnetic Fields , 2018, IEEE Transactions on Industrial Electronics.

[9]  Liyi Li,et al.  Optimization of a Coil System for Generating Uniform Magnetic Fields inside a Cubic Magnetic Shield , 2018 .

[10]  Fatimah Ibrahim,et al.  An Improved Wearable Resonant Wireless Power Transfer System for Biomedical Capsule Endoscope , 2018, IEEE Transactions on Industrial Electronics.

[11]  Francisco Granziera,et al.  Three-Axial Helmholtz Coil Design and Validation for Aerospace Applications , 2018, IEEE Transactions on Aerospace and Electronic Systems.

[12]  Reza Beiranvand,et al.  Effects of the Winding Cross-Section Shape on the Magnetic Field Uniformity of the High Field Circular Helmholtz Coil Systems , 2017, IEEE Transactions on Industrial Electronics.

[13]  Fatimah Ibrahim,et al.  Stable and High-Efficiency Wireless Power Transfer System for Robotic Capsule Using a Modified Helmholtz Coil , 2017, IEEE Transactions on Industrial Electronics.

[14]  J. Nam,et al.  A Spiral Microrobot Performing Navigating Linear and Drilling Motions by Magnetic Gradient and Rotating Uniform Magnetic Field for Applications in Unclogging Blocked Human Blood Vessels , 2015, IEEE Transactions on Magnetics.

[15]  Gen Uehara,et al.  Calibration for a Multichannel Magnetic Sensor Array of a Magnetospinography System , 2014, IEEE Transactions on Magnetics.

[16]  G. Bison,et al.  Dynamic stabilization of the magnetic field surrounding the neutron electric dipole moment spectrometer at the Paul Scherrer Institute , 2014, 1408.6752.

[17]  R Beiranvand,et al.  Magnetic field uniformity of the practical tri-axial Helmholtz coils systems. , 2014, The Review of scientific instruments.

[18]  R. Beiranvand Analyzing the uniformity of the generated magnetic field by a practical one-dimensional Helmholtz coils system. , 2013, The Review of scientific instruments.

[19]  C. Coillot,et al.  Autocalibration Method for Anisotropic Magnetoresistive Sensors Using Offset Coils , 2013, IEEE Sensors Journal.

[20]  A. Hadidi,et al.  Effect of a uniform magnetic field on dielectric two-phase bubbly flows using the level set method , 2012 .

[21]  Kohji Koshiji,et al.  Magnetic-Field Immunity Examination and Evaluation of Transcutaneous Energy-Transmission System for a Totally Implantable Artificial Heart , 2012 .

[22]  Hisayoshi Shimizu,et al.  Magnetic Cleanliness Program Under Control of Electromagnetic Compatibility for the SELENE (Kaguya) Spacecraft , 2010 .

[23]  Wenying Yang,et al.  3-D Finite Element Analysis of Dynamic Characteristics of Twin-Type Relay Interfered by Uniform Constant Magnetic Field , 2008, IEICE Trans. Electron..

[24]  C. Kang,et al.  Square Loop Coil System for Balancing and Calibration of Second-Order SQUID Gradiometers , 2007, IEEE Transactions on Applied Superconductivity.

[25]  R. Pinčák,et al.  Effect of symmetry on the electronic structure of spheroidal fullerenes in a weak uniform magnetic field , 2007, cond-mat/0703336.

[26]  V. M. Primiani,et al.  Immunity tests of implantable cardiac pacemaker against CW and pulsed ELF fields: experimental and numerical results , 2006, IEEE Transactions on Electromagnetic Compatibility.

[27]  J. Hourtoule,et al.  Magnetic compatibility of standard components for electrical installations: Tests on programmable logical controllers and other electronic devices , 2005 .

[28]  D. Desideri,et al.  Magnetic compatibility of standard components for electrical installations: Tests on low voltage circuit breakers and contactors , 2005 .

[29]  Norbert Felber,et al.  In vitro exposure apparatus for ELF magnetic fields , 2004, Bioelectromagnetics.

[30]  G Gottardi,et al.  A four coil exposure system (tetracoil) producing a highly uniform magnetic field , 2003, Bioelectromagnetics.

[31]  G. Stroink,et al.  Uniform magnetic field produced by three, four, and five square coils , 1983 .

[32]  I. Scollar,et al.  Square cross section coils for the production of uniform magnetic fields , 1967 .

[33]  Arthur H. Firester,et al.  Design of Square Helmholtz Coil Systems , 1966 .

[34]  Sidney M. Rubens,et al.  Cube‐Surface Coil for Producing a Uniform Magnetic Field , 1945 .

[35]  Seong Young Ko,et al.  Position-based magnetic field control for an electromagnetic actuated microrobot system , 2014 .

[36]  J. Kirschvink,et al.  Uniform magnetic fields and double-wrapped coil systems: improved techniques for the design of bioelectromagnetic experiments. , 1992, Bioelectromagnetics.