36results about How to "High air gap magnetic induction" patented technology

A cylindrical enclosed magnetic-field-type electromagnetic shake table magnetic circuit structure centripetally excited by a long permanent magnetism tube belongs to the technical field of vibration measurement. A cylindrical enclosed magnetic field structure is provided, the permanent magnetism tube is coaxially assembled in the inner part of a long cylindrical outer magnet yoke in a bonded manner, magnetic poles of the inner cylindrical surface of the permanent magnetism tube are identical in polarity, an enclosed magnetic circuit is formed through magnet yokes, and a magnetic field high in uniformity is generated in an air gap. After a working coil is powered on, the working coil in the magnetic field is affected by a Lorentz force and generates a precise and controllable electromagnetic driving force. The surface, adjacent to the air gap, of a central magnet yoke is provided with an array-type microstructure arranged in a deep channel mode, and the eddy current loss can be effectively inhibited. According to the invention, a large stroke, high magnetic field uniformity, a large thrust and linear electromagnetic driving force characteristics can be considered at the same time, defects of an existing technical scheme are effectively overcome, and a high-precision and large-stoke electromagnetic shake table magnetic circuit structure technical scheme is provided for low-frequency / ultralow-frequency vibration calibration.

The invention discloses a long permanent magnet pipe centripetal excitation cylindrical confined magnetic field type electromagnetic vibration table magnetic structure based on magnetic field tracking compensation and belongs to the technical field of vibration measurement. The cylindrical confined magnetic field structure is provided, a permanent magnet pipe is coaxially assembled inside a long cylindrical outer yoke in a bonding mode, magnetic poles on the inner surface of the permanent magnet pipe are of the same the polarity, a closed magnetic circuit is formed by yokes, high-uniformity magnetic field distribution is realized in an air gap, compensating coils are evenly wound around a center yoke, the direction of the current of the compensating coils is opposite to that of a working coil, synchronous current phase tracking is achieved for the compensating coils and the working coil, the current amplitudes of the compensating coils and the working coil are in proportion, and a formed compensating magnetic field can conduct synchronous tracking compensation on the influence of armature reaction. According to the structure, large stroke, high magnetic field uniformity, large thrust and linear electromagnetic driving force can all be realized, and a high-precision large-stroke electromagnetic vibration table magnetic structure technical scheme is provided for low-frequency / ultralow-frequency vibration calibration.

The invention provides a cylindrical closed magnetic field type low-frequency vibration calibration table with long permanent magnet tube radial excitation, belonging to the field of vibration measurement technology. A cylindrical closed type magnetic field structure design is provided. A permanent magnet tube is coaxially and adhesively installed in a long cylindrical outer magnet yoke to carry out excitation. The polarities of permanent magnet tube inner surface magnetic poles are the same. Closed magnetic circuits are formed by magnet yokes. The magnetic induction intensity distribution with high uniformity is generated in air gaps. The surface of a center magnet yoke adjacent to the air gaps is provided with an array type micro structure in the form of deep trenches, and the eddy current loss can be effectively inhibited. The organic integration design of air lubricated guide technology is employed, and outstanding electromagnetic drive mechanical performance and high movement guide precision are obtained at the same time. According to the cylindrical closed magnetic field type low-frequency vibration calibration table, large stroke, high thrust and a linear electromagnetic driving force characteristic and high movement guide precision can be considered, and a high precision and large stroke high performance low frequency vibration calibration table technical scheme is provided for low-frequency / ultra-low frequency vibration calibration.

The invention provides a double-row permanent magnet centripetal excitation rectangular open magnetic field type electromagnetic vibration table magnetic circuit structure with eddy current compensation, belonging to the field of vibration measurement technology. A rectangular open type magnetic field structure design is provided. Two rows of permanent magnets are symmetrically installed at the inner side of a long magnet yoke and face magnetic poles. Two symmetric closed magnetic circuits are formed by magnet yokes. The magnetic induction density distribution with high uniformity is generated in air gaps. After a working coil is energized, the working coil is affected by Lorentz force in a magnetic field, and precisely controllable electromagnetic drive force is generated. The surface of a center magnet yoke adjacent to the air gaps is provided with an array type micro structure in the form of deep trenches, and the eddy current loss can be effectively inhibited. According to the double-row permanent magnet centripetal excitation rectangular open magnetic field type electromagnetic vibration table magnetic circuit structure, large stroke, high magnetic field uniformity, high thrust and a linear electromagnetic driving force characteristic can be considered, and a high precision and large stroke electromagnetic vibration table magnetic circuit structure technical scheme is provided for low-frequency / ultra-low frequency vibration calibration.

The invention provides a double-row permanent magnet centripetal excitation rectangular open magnetic field type electromagnetic vibration table magnetic circuit structure with eddy current compensation, belonging to the field of vibration measurement technology. A rectangular open type magnetic field structure design is provided. Two rows of permanent magnets are symmetrically installed at the inner side of a long magnet yoke and face magnetic poles. Two symmetric closed magnetic circuits are formed by magnet yokes. The magnetic induction density distribution with high uniformity is generated in air gaps. After a working coil is energized, the working coil is affected by Lorentz force in a magnetic field, and precisely controllable electromagnetic drive force is generated. The surface of a center magnet yoke adjacent to the air gaps is provided with an array type micro structure in the form of deep trenches, and the eddy current loss can be effectively inhibited. According to the double-row permanent magnet centripetal excitation rectangular open magnetic field type electromagnetic vibration table magnetic circuit structure, large stroke, high magnetic field uniformity, high thrust and a linear electromagnetic driving force characteristic can be considered, and a high precision and large stroke electromagnetic vibration table magnetic circuit structure technical scheme is provided for low-frequency / ultra-low frequency vibration calibration.

The invention relates to a rectangular low-frequency vibration calibration console with magnetic field tracking compensation and symmetric excitation on both ends of double magnetic circuits and belongs to the vibration metering technical field. A rectangular open-magnetic-field magnetic circuit structure is provided. Two permanent magnets are symmetrically installed on both ends of a central magnet yoke and the same poles of the two permanent magnets are arranged oppositely. Two symmetric closed magnetic circuits are formed by the magnet yoke and generate a strong magnetic field with high uniformity in an air gap. The surface of the magnet yoke adjacent to the air gap is equipped with an array microstructure in the form of a deep groove so as to be capable of effectively suppressing eddy-current loss. A compensating coil is arranged on the central magnetic yoke and form a compensating magnetic field which performs synchronous tracking compensation on an influence of armature reaction. The rectangular low-frequency vibration calibration console is designed in combination with static pressure air floating guiding technology and a prominent electromagnetic driving mechanical property and high motion guiding precision are acquired. The rectangular low-frequency vibration calibration console integrates large stroke, large thrust, a linear electromagnetic driving force characteristic, and high motion guiding precision, and provides a high-performance low-frequency vibration calibration console technical scheme with high precision and large stroke for low-frequency / ultralow-frequency vibration calibration.

A long permanent magnetism tube centripetally-excited cylindrical low-frequency vibration calibration bench capable of realizing magnetic field tracking compensation belongs to the technical field of vibration measurement. A cylindrical enclosed magnetic field structure is provided, a permanent magnetism tube is coaxially assembled in the inner part of a long cylindrical outer magnet yoke in a bonded manner to carry out excitation, magnetic poles of the inner cylindrical surface of the permanent magnetism tube are identical in polarity, an enclosed magnetic circuit is formed through magnet yokes, a magnetic field high in uniformity is generated in an air gap, a compensation coil is uniformly winded on a central magnet yoke to form a compensation magnetic field for carrying out tracking compensation on the influences of an armature reaction, the long permanent magnetism tube centripetally-excited cylindrical low-frequency vibration calibration bench is organically integrated with a static pressure air floatation guiding technology, and outstanding electromagnetic drive mechanical characteristics and high motion guiding precision are realized at the same time. According to the invention, a large stroke, a large thrust, linear electromagnetic drive force characteristics and high motion guiding precision can be considered at the same time, and a high-precision large-stoke high-performance low-frequency vibration calibration bench technical scheme is provided for low-frequency / ultralow-frequency vibration calibration.

A cylindrical enclosed magnetic-field-type electromagnetic shake table magnetic circuit structure centripetally excited by a long permanent magnetism tube belongs to the technical field of vibration measurement. A cylindrical enclosed magnetic field structure is provided, the permanent magnetism tube is coaxially assembled in the inner part of a long cylindrical outer magnet yoke in a bonded manner, magnetic poles of the inner cylindrical surface of the permanent magnetism tube are identical in polarity, an enclosed magnetic circuit is formed through magnet yokes, and a magnetic field high in uniformity is generated in an air gap. After a working coil is powered on, the working coil in the magnetic field is affected by a Lorentz force and generates a precise and controllable electromagnetic driving force. The surface, adjacent to the air gap, of a central magnet yoke is provided with an array-type microstructure arranged in a deep channel mode, and the eddy current loss can be effectively inhibited. According to the invention, a large stroke, high magnetic field uniformity, a large thrust and linear electromagnetic driving force characteristics can be considered at the same time, defects of an existing technical scheme are effectively overcome, and a high-precision and large-stoke electromagnetic shake table magnetic circuit structure technical scheme is provided for low-frequency / ultralow-frequency vibration calibration.

The invention provides a rectangular open magnetic field type low-frequency vibration calibration table with double-magnetic-circuit two-end symmetric excitation, belonging to the field of vibration measurement technology. A rectangular open magnetic field type magnetic circuit structure is provided. Two permanent magnets are symmetrically installed at two ends of a center magnet yoke and face magnetic poles. Two symmetric closed magnetic circuits are formed by magnet yokes. The strong magnetic field distribution with high uniformity is generated in air gaps. After a working coil is energized, the working coil is affected by Lorentz force in a magnetic field, and precisely controllable electromagnetic drive force is generated. The surfaces of the magnet yokes adjacent to the air gaps are provided with an array type micro structure in the form of deep trenches, and the eddy current loss can be effectively inhibited. The organic integration design of air lubricated guide technology is employed, and outstanding electromagnetic drive mechanical performance and high movement guide precision are obtained at the same time. According to the rectangular open magnetic field type low-frequency vibration calibration table, large stroke, high thrust, a linear electromagnetic driving force characteristic and high movement guide precision can be considered, and the high performance low frequency vibration calibration table is provided for low-frequency / ultra-low frequency vibration calibration.

The invention provides a double-row permanent magnet centripetal excitation rectangular low frequency vibration table with magnetic field tracking compensation, belonging to the field of vibration measurement technology. A rectangular open magnetic field type magnetic circuit structure is provided. Two rows of permanent magnets are symmetrically installed at the inner side surfaces of a long magnet yoke and face magnetic poles. Two symmetric closed magnetic circuits are formed by magnet yokes. The strong magnetic field distribution with high uniformity is generated in air gaps. The surfaces of the magnet yoke adjacent to the air gaps are provided with an array type micro structure in the form of deep trenches, and the eddy current loss can be effectively inhibited. The center magnet yoke is provided with a compensation coil, and a formed compensation magnetic field carries out synchronous tracking compensation on the influence of an armature reaction. The organic integration design of air lubricated guide technology is employed, and outstanding electromagnetic drive mechanical performance and high movement guide precision can be obtained at the same time. According to the double-row permanent magnet centripetal excitation rectangular low frequency vibration table, large stroke, high thrust, a linear electromagnetic driving force characteristic and high movement guide precision can be considered, and a high precision and large stroke high performance low frequency vibration calibration table technical scheme is provided for low-frequency / ultra-low frequency vibration calibration.

The invention provides a four-magnetic-circuit symmetric excitation rectangular low frequency vibration calibration table with magnetic field tracking compensation, belonging to the field of vibration measurement technology. A rectangular open magnetic field type magnetic circuit structure is disclosed. Four permanent magnets are symmetrically installed at two ends of two outer magnet yokes and face magnetic poles. Four symmetric closed magnetic circuits are formed by magnet yokes. The magnetic induction intensity distribution with high uniformity is generated in air gaps. The surfaces of the magnet yokes adjacent to the air gaps are provided with an array type micro structure in the form of deep trenches, and the eddy current loss can be effectively inhibited. The center magnet yoke is provided with a compensation coil, and a formed compensation magnetic field carries out synchronous tracking compensation on the influence of an armature reaction. The organic integration design of air lubricated guide technology is employed, and outstanding electromagnetic drive mechanical performance and high movement guide precision are obtained at the same time. According to the four-magnetic-circuit symmetric excitation rectangular low frequency vibration calibration table, large stroke, high thrust, a linear electromagnetic driving force characteristic and high movement guide precision can be considered, and a high precision and large stroke high performance low frequency vibration calibration table is provided for low-frequency / ultra-low frequency vibration calibration.

The invention provides a cylindrical closed magnetic field type low-frequency vibration calibration table with long permanent magnet tube radial excitation, belonging to the field of vibration measurement technology. A cylindrical closed type magnetic field structure design is provided. A permanent magnet tube is coaxially and adhesively installed in a long cylindrical outer magnet yoke to carry out excitation. The polarities of permanent magnet tube inner surface magnetic poles are the same. Closed magnetic circuits are formed by magnet yokes. The magnetic induction intensity distribution with high uniformity is generated in air gaps. The surface of a center magnet yoke adjacent to the air gaps is provided with an array type micro structure in the form of deep trenches, and the eddy current loss can be effectively inhibited. The organic integration design of air lubricated guide technology is employed, and outstanding electromagnetic drive mechanical performance and high movement guide precision are obtained at the same time. According to the cylindrical closed magnetic field type low-frequency vibration calibration table, large stroke, high thrust and a linear electromagnetic driving force characteristic and high movement guide precision can be considered, and a high precision and large stroke high performance low frequency vibration calibration table technical scheme is provided for low-frequency / ultra-low frequency vibration calibration.

The invention provides a rectangular open magnetic field type electromagnetic vibration table magnetic circuit structure with double-magnetic-circuit two-end symmetric excitation, belonging to the field of vibration measurement technology. A rectangular open type magnetic field structure design is provided. Two permanent magnets are symmetrically installed at two ends of a center magnet yoke and face magnetic poles. Two symmetric closed magnetic circuits are formed by magnet yokes. The magnetic induction intensity distribution with high uniformity is generated in air gaps. After a working coil is energized, the working coil is affected by Lorentz force in a magnetic field, and precisely controllable electromagnetic drive force is generated. The surfaces of the magnet yokes adjacent to the air gaps are provided with an array type micro structure in the form of deep trenches, and the eddy current loss can be effectively inhibited. According to the rectangular open magnetic field type electromagnetic vibration table magnetic circuit structure, large stroke, high magnetic field uniformity, high thrust and a linear electromagnetic driving force characteristic can be considered, the disadvantages in the existing technical scheme can be effectively solved, and a high precision and large stroke electromagnetic vibration table magnetic circuit structure technical scheme is provided for low-frequency / ultra-low frequency vibration calibration.

The invention provides a double-magnetic-circuit two-end symmetric excitation cylindrical closed magnetic field type electromagnetic vibration table magnetic circuit structure with eddy current compensation, belonging to the field of vibration measurement technology. A cylindrical closed type magnetic field structure design is provided. Two cylindrical permanent magnets are symmetrically installed at two ends of a center magnet yoke and face magnetic poles. Two symmetric closed magnetic circuits are formed by magnet yokes. The magnetic induction intensity distribution with high uniformity is generated in air gaps. After a working coil is energized, the working coil is affected by Lorentz force in a magnetic field, and precisely controllable electromagnetic drive force is generated. The surfaces of the magnet yokes adjacent to the air gaps are provided with an array type micro structure in the form of deep trenches, and the eddy current loss can be effectively inhibited. According to the double-magnetic-circuit two-end symmetric excitation cylindrical closed magnetic field type electromagnetic vibration table magnetic circuit structure, large stroke, high magnetic field uniformity, high thrust and a linear electromagnetic driving force characteristic can be considered, and a high precision and large stroke electromagnetic vibration table magnetic circuit structure technical scheme is provided for low-frequency / ultra-low frequency vibration calibration.

The invention relates to a rectangular low-frequency vibration calibration console with magnetic field tracking compensation and symmetric excitation on both ends of double magnetic circuits and belongs to the vibration metering technical field. A rectangular open-magnetic-field magnetic circuit structure is provided. Two permanent magnets are symmetrically installed on both ends of a central magnet yoke and the same poles of the two permanent magnets are arranged oppositely. Two symmetric closed magnetic circuits are formed by the magnet yoke and generate a strong magnetic field with high uniformity in an air gap. The surface of the magnet yoke adjacent to the air gap is equipped with an array microstructure in the form of a deep groove so as to be capable of effectively suppressing eddy-current loss. A compensating coil is arranged on the central magnetic yoke and form a compensating magnetic field which performs synchronous tracking compensation on an influence of armature reaction. The rectangular low-frequency vibration calibration console is designed in combination with static pressure air floating guiding technology and a prominent electromagnetic driving mechanical property and high motion guiding precision are acquired. The rectangular low-frequency vibration calibration console integrates large stroke, large thrust, a linear electromagnetic driving force characteristic, and high motion guiding precision, and provides a high-performance low-frequency vibration calibration console technical scheme with high precision and large stroke for low-frequency / ultralow-frequency vibration calibration.

The invention provides a double-permanent-magnetic-tube two-end symmetric excitation cylindrical closed magnetic field type electromagnetic vibration table magnetic circuit structure with magnetic field tracking compensation, belonging to the field of vibration measurement technology. A cylindrical closed type magnetic field structure design is provided. Two permanent magnet tubes are symmetrically installed and face magnetic poles. Two symmetric closed magnetic circuits are formed by magnet yokes. The magnetic induction intensity distribution with high uniformity is generated in air gaps. The surfaces of the magnet yokes adjacent to the air gaps are provided with an array type micro structure in the form of deep trenches, and the eddy current loss can be effectively inhibited. A center magnet yoke is provided with a compensation coil, the direction of the current is opposite to that in a working coil, phase tracking is synchronized, amplitudes are proportional, and a formed compensation magnetic field can carry out synchronous tracking compensation on the influence of an armature reaction. According to the double-permanent-magnetic-tube two-end symmetric excitation cylindrical closed magnetic field type electromagnetic vibration table magnetic circuit structure, large stroke, high magnetic field uniformity, high thrust and a linear electromagnetic driving force characteristic can be considered, and a high precision and large stroke electromagnetic vibration table magnetic circuit structure technical scheme is provided for low-frequency / ultra-low frequency vibration calibration.

The invention provides a double-magnetic-circuit two-end symmetric excitation rectangular open magnetic field type electromagnetic vibration table magnetic circuit structure with magnetic field tracking compensation, belonging to the field of vibration measurement technology. A rectangular open type magnetic field structure design is provided. Two permanent magnets are symmetrically installed at two ends of a center magnet yoke and face magnetic poles. Two symmetric closed magnetic circuits are formed by magnet yokes. The magnetic induction intensity distribution with high uniformity is generated in air gaps. The surfaces of the magnet yokes adjacent to the air gaps are provided with an array type micro structure in the form of deep trenches, and the eddy current loss can be effectively inhibited. The center magnet yoke is provided with a compensation coil, the direction of the current is opposite to that in a working coil, phase tracking is synchronized, amplitudes are proportional, and a formed compensation magnetic field can carry out synchronous tracking compensation on the influence of an armature reaction. According to the double-magnetic-circuit two-end symmetric excitation rectangular open magnetic field type electromagnetic vibration table magnetic circuit structure, large stroke, high magnetic field uniformity, high thrust and a linear electromagnetic driving force characteristic can be considered, and a high precision and large stroke electromagnetic vibration table magnetic circuit structure technical scheme is provided for low-frequency / ultra-low frequency vibration calibration.

A rectangular open magnetic field type electromagnetic vibration table magnetic circuit structure symmetrically excited by four magnetic circuits relates to the technical field of vibration measurement. A rectangular open magnetic field structure design is put forward. Four permanent magnets are symmetrically installed at the two ends of two outer yokes, and the same magnetic poles are arranged oppositely. Four symmetrical closed magnetic circuits are formed through the yokes. High-uniformity magnetic induction intensity distribution is generated in air gaps. After powered on, a working coil generates precision-controllable electromagnetic driving force in a magnetic field under the action of Lorentz force. The surfaces of yokes adjacent to the air gaps are respectively provided with a deep trench type array microstructure which can effectively inhibit eddy current loss. According to the invention, the characteristics of large stroke, high magnetic field uniformity, big thrust and linear electromagnetic driving force are all taken into consideration. The shortcomings of the existing technical scheme can be solved effectively. A high-precision and large-stroke electromagnetic vibration table magnetic circuit structure technical scheme is provided for low-frequency and ultralow-frequency vibration calibration.

The invention provides a double-row permanent magnet centripetal excitation rectangular open magnetic field type low frequency vibration table with eddy current compensation, belonging to the field of vibration measurement technology. A rectangular open magnetic field type magnetic circuit structure is provided. Two rows of permanent magnets are symmetrically installed at the inner side surfaces of a long magnet yoke and face magnetic poles. Two symmetric closed magnetic circuits are formed by magnet yokes. The strong magnetic field distribution with high uniformity is generated in air gaps. After a working coil is energized, the working coil is affected by Lorentz force in a magnetic field, and precisely controllable electromagnetic drive force is generated. The surface of a center magnet yoke adjacent to the air gaps is provided with an array type micro structure in the form of deep trenches, and the eddy current loss can be effectively inhibited. The organic integration design of air lubricated guide technology is employed, and outstanding electromagnetic drive mechanical performance and high movement guide precision are obtained at the same time. According to the double-row permanent magnet centripetal excitation rectangular open magnetic field type low frequency vibration table, large stroke, high thrust, a linear electromagnetic driving force characteristic and high movement guide precision can be considered, and a high precision and large stroke high performance low frequency vibration calibration table technical scheme is provided for low-frequency / ultra-low frequency vibration calibration.

The invention discloses a long permanent magnet pipe centripetal excitation cylindrical confined magnetic field type electromagnetic vibration table magnetic structure based on magnetic field tracking compensation and belongs to the technical field of vibration measurement. The cylindrical confined magnetic field structure is provided, a permanent magnet pipe is coaxially assembled inside a long cylindrical outer yoke in a bonding mode, magnetic poles on the inner surface of the permanent magnet pipe are of the same the polarity, a closed magnetic circuit is formed by yokes, high-uniformity magnetic field distribution is realized in an air gap, compensating coils are evenly wound around a center yoke, the direction of the current of the compensating coils is opposite to that of a working coil, synchronous current phase tracking is achieved for the compensating coils and the working coil, the current amplitudes of the compensating coils and the working coil are in proportion, and a formed compensating magnetic field can conduct synchronous tracking compensation on the influence of armature reaction. According to the structure, large stroke, high magnetic field uniformity, large thrust and linear electromagnetic driving force can all be realized, and a high-precision large-stroke electromagnetic vibration table magnetic structure technical scheme is provided for low-frequency / ultralow-frequency vibration calibration.

Provided is a magnetic circuit structure for a rectangular open-type magnetic field of an electromagnetic shaking table by adopting double rows of permanent magnets with centripetal excitation for tracking and compensation of the magnetic field, pertaining to the technical field of vibration and measurement. Provided is structural design of the rectangular open-type magnetic field. The double rows of permanent magnets are symmetrically arranged at insides of long magnet yokes with same magnetic poles oppositely arranged. By means of magnet yokes, a symmetrical closed magnetic circuit is formed. Magnetic inductive intensity distribution with high evenness is generated in an air gap. Compensating coils are arranged on a central magnet yoke. Galvanized electric current is opposite to electric current of working coils in direction and proportionate to phase synchronous tracking and amplitude. A formed compensating magnetic field is used for tracking and compensating for influence of armature reaction. Considerations are taken into large stroke, uniformity of a high magnetic field, high thrust and features of linear electromagnetic driving force so that a technical scheme, with high precision and large stroke, of the magnetic circuit structure of the electromagnetic shaking table is provided for low frequency / ultra-low frequency vibration calibration.

A double-magnetic-circuit symmetrically-excited cylindrical enclosed magnetic-field-type electromagnetic shake table magnetic circuit structure capable of realizing magnetic field tracking compensation belongs to the technical field of vibration measurement. A cylindrical enclosed magnetic field structure is provided, two cylindrical permanent magnets are symmetrically installed on two ends of a central magnet yoke, and same magnetic poles are arranged in an opposite manner; two symmetrical enclosed magnetic circuits are formed through magnet yokes, the magnetic induction intensity high in uniformity is generated in an air gap; the surface, adjacent to the air gap, of the magnet yoke is provided with an array-type microstructure arranged in a deep channel mode, and the eddy current loss can be effectively inhibited; and a central magnet yoke is provided with a compensation coil, a provided current is opposite to the current in a working coil in direction and is proportional to the current in the working coil in phase synchronous tracking and amplitude, and a formed compensation magnetic field is capable of carrying out synchronous tracking compensation on the influences of an armature reaction. According to the invention, a large stroke, high magnetic field uniformity, a large thrust and linear electromagnetic driving force characteristics can be considered at the same time, and a high-precision and large-stoke electromagnetic shake table magnetic circuit structure technical scheme is provided for low-frequency / ultralow-frequency vibration calibration.