CN-122025334-A - High-gain three-dimensional magnetic field generator based on closed magnetic circuit

Abstract

The invention discloses a high-gain three-dimensional magnetic field generator based on a closed magnetic circuit, which comprises a central working air gap, three groups of mutually orthogonal independent magnetic yokes, three groups of independent exciting coils and three groups of open copper shells surrounding the ends of the corresponding magnetic yokes, wherein each group of magnetic yokes comprises two magnetic yokes, two magnetic yokes in each group are respectively positioned at two sides of the central working air gap, the three groups of exciting coils are respectively wound on the corresponding magnetic yokes, the three groups of magnetic yokes are respectively arranged in an orthogonal mode along an X axis, a Y axis and a Z axis of a space rectangular coordinate system, the magnetic pole face of each magnetic yoke faces towards the central working air gap, and the three groups of magnetic yokes and the central working air gap form three independent low-reluctance closed magnetic circuits together. According to the invention, by constructing the three-axis orthogonal ferromagnetic paths, the magnetic resistance of the main magnetic circuit is greatly reduced by utilizing the high magnetic conductivity characteristic of the ferromagnetic material, the capability of generating a high-strength central magnetic field is improved, and the exciting current and the corresponding loss required by the same magnetic field are reduced.

Inventors

• Jiao Yuqiao
• CHEN WU
• SUN JIANFEI
• Shen zhan
• Ding sihang
• SHI YUJIA
• LI XINYU
• CHEN PI
• RUAN LIANGCHENG
• FU YIQIAO
• WANG PENG

Assignees

• 东南大学

Dates

Publication Date

20260512

Application Date

20260304

Claims (6)

1. 1. A high-gain three-dimensional magnetic field generator based on a closed magnetic circuit is characterized by comprising, A central working air gap; three groups of mutually orthogonal independent magnetic yokes, each group of magnetic yokes comprises two magnetic yokes, and the two magnetic yokes in each group are respectively positioned at two sides of the central working air gap; three groups of independent exciting coils wound on the corresponding magnet yokes respectively, and Three groups of open copper shells surrounding the ends of the corresponding magnetic yokes; The three groups of magnetic yokes are respectively arranged along the X axis, the Y axis and the Z axis of the space rectangular coordinate system in an orthogonal mode, the magnetic pole face of each magnetic yoke faces the central working air gap, and the three groups of magnetic yokes and the central working air gap form three independent low-reluctance closed magnetic circuits.
2. 2. The high-gain three-dimensional magnetic field generator based on a closed magnetic circuit according to claim 1, wherein three groups of exciting coils are used for receiving external exciting current and generating magnetomotive force, controlling magnetic induction intensity components corresponding to three directions of an X axis, a Y axis and a Z axis in a central working air gap, and generating a composite magnetic field with adjustable size and direction in the central working air gap through vector superposition.
3. 3. The high-gain three-dimensional magnetic field generator based on a closed magnetic circuit according to claim 1, wherein the three groups of magnetic yokes are made of ferromagnetic materials with high magnetic permeability, and the ferromagnetic materials are silicon steel sheets, ferrite or soft magnetic composite materials.
4. 4. The high-gain three-dimensional magnetic field generator based on a closed magnetic circuit according to claim 1, wherein the end face shape of the magnetic pole of the magnetic yoke is arranged in a quadrangular frustum of a pyramid.
5. 5. The high-gain three-dimensional magnetic field generator based on a closed magnetic circuit according to claim 1, wherein the open copper shell covers the magnetic pole end face of the magnetic yoke.
6. 6. The high-gain three-dimensional magnetic field generator based on a closed magnetic circuit according to claim 1, wherein a magnetic shielding shell is further arranged outside the three-dimensional magnetic field generator, and the magnetic shielding shell is made of ferromagnetic materials with high magnetic permeability.

Description

High-gain three-dimensional magnetic field generator based on closed magnetic circuit Technical Field The invention belongs to the technical field of power electronics, and particularly relates to a high-gain three-dimensional magnetic field generator based on a closed magnetic circuit. Background In the field of power electronics and electromagnetic devices, three-dimensional magnetic field generators play a key role in the application context of various disciplines of materials, electronics, biology, medicine, aerospace, chemistry, application physics, including, but not limited to, magnetic field simulation, magnetic sensor calibration, medical treatments such as Transcranial Magnetic Stimulation (TMS), and electromagnetic compatibility testing environments. Such generators are intended to generate controllable magnetic fields whose magnitude and direction are adjustable in three orthogonal spatial dimensions. Currently, the main technique for achieving such three-dimensional magnetic fields is to use orthogonally arranged helmholtz coils. The helmholtz coil consists of two identical circular coils, coaxially placed with a pitch equal to their radius, producing a relatively uniform magnetic field along the axis in the central area. To extend into three dimensions, three such pairs of coils are arranged in mutually perpendicular directions, each pair controlling an axis. This arrangement allows vector superposition of magnetic fields to produce a resultant field with adjustable direction and strength by varying the current in each pair independently. However, this device uses air as a magnetic medium, resulting in a high magnetic resistance in the magnetic circuit, and it is difficult to obtain a high-strength magnetic field while generating a large amount of loss, and in addition, the leakage of magnetic flux due to the open magnetic circuit makes it highly sensitive to geometric asymmetry, external disturbance and other factors, and it is difficult to precisely control the generated magnetic field while generating poor uniformity and focusing, and electromagnetic interference may be generated to surrounding precision instruments. In response to these problems, the currently available improvements mainly include increasing the number of coil turns, using superconducting materials, or using hybrid coil systems. However, these methods do not fundamentally solve the problem caused by the three-dimensional helmholtz magnetic field generating system using air as a magnetic medium, but instead add new requirements and constraints, such as requirements of superconducting materials on temperature, and the hybrid coil system sacrifices three-dimensional orthogonality, etc. Disclosure of Invention The invention mainly aims to provide a high-gain three-dimensional magnetic field generator based on a closed magnetic circuit, and aims to solve the problems that a traditional three-dimensional Helmholtz coil is large in magnetic resistance, low in electro-magnetic conversion efficiency, large in power consumption and difficult to generate a high-strength magnetic field in the center due to the adoption of an air magnetic circuit. The invention aims to provide a high-gain three-dimensional magnetic field generator based on a closed magnetic circuit, which realizes focusing of a magnetic field in a smaller area through the special shape of an end magnetic core, and realizes extremely low excitation power consumption and extremely high magnetic field gain on the premise of ensuring three-dimensional controllability of the magnetic field direction and the magnetic field size by utilizing a vector superposition principle to generate a composite magnetic field with adjustable direction and size in a central air gap. In order to achieve the above object, the solution of the present invention is: A high-gain three-dimensional magnetic field generator based on a closed magnetic circuit comprises, A central working air gap; three groups of mutually orthogonal independent magnetic yokes, each group of magnetic yokes comprises two magnetic yokes, and the two magnetic yokes in each group are respectively positioned at two sides of the central working air gap; three groups of independent exciting coils wound on the corresponding magnet yokes respectively, and Three groups of open copper shells surrounding the ends of the corresponding magnetic yokes; The three groups of magnetic yokes are respectively arranged along the X axis, the Y axis and the Z axis of the space rectangular coordinate system in an orthogonal mode, the magnetic pole face of each magnetic yoke faces the central working air gap, and the three groups of magnetic yokes and the central working air gap form three independent low-reluctance closed magnetic circuits. The three groups of exciting coils are used for receiving external exciting current and generating magnetomotive force, and controlling magnetic induction intensity components corresponding to the X axis, t