41results about How to "Eliminate mutual inductance" patented technology

The invention relates to an electromagnetic prospecting sending-receiving integration method and a device. The invention is suitable for the fields of geophysical prospecting, engineering geological prospecting, underground military target detection, nondestructive inspection and the like. The technical scheme of the invention is as follows: arranging an inner receiving coil 1 in a sending coil 3; arranging an outer receiving coil 2 outside the sending coil 3; ensuring that magnetic flux passing through the inner receiving coil 1 and the outer receiving coil 2 is equivalent and is in opposite sign under the action of primary field; mutually offsetting primary field induced voltage; and only outputting a secondary field signal. The device comprises a transmitter 4, a sending coil 3, an inner receiving coil 1, an outer receiving coil 2, a signal conditioning circuit 5 and a receiver 6, wherein the inner receiving coil 1 is connected with the outer receiving coil 2, and the coil 1 and the coil 2 are connected with the signal conditioning circuit 5. The invention has the advantages of eliminating primary field influence, reducing signal dynamic range, expanding the practicability of small-wireframe same-point device and realizing integration of the sending coil and the receiving coil.

The invention provides a transient electromagnetic detection apparatus and a method of eliminating inductive disturbance. The transient electromagnetic detection apparatus includes a coil device and aframework carrier, wherein the coil device includes dual transmission coils, receiving coils and a coil fixing mount; the dual transmission coils include first and second transmission coils which areparallel to each other, are not in the same plane and can generate counter magnetic fields at the center of the respective coil at any power-on moment; the receiving coils are arranged between the dual transmission coils, and for the distance, the constraint is that earlier signals are not beyond the amplitude; a rotation shaft which is parallel to the dual transmission coils and can drive the coil device to overturn is arranged on the coil fixing mount; and a nonmetal handle is arranged on the rotation shaft. The method of eliminating inductive disturbance measures the signals before and after 180DEG overturning of the coil device at the same position point and performs difference processing, by enabling the transmission coils in the detection apparatus to approach the area to be detected and enabling the normal of the transmission coils to be perpendicular to the area to be detected. The method of eliminating inductive disturbance enables earlier signals not to be beyond amplitude,and can capture whole course secondary field signals by eliminating inductive disturbance and enhance the distinguishing result.

The invention discloses a transverse flux permanent-magnet planar motor, and relates to the filed of motors. The transverse flux permanent-magnet planar motor solves the problems of limited stroke of a rotor, low thrust density, complicated structure of the motor, low current control accuracy and the like in the conventional permanent-magnet planar motor. The primary of the motor consists of a plurality of motor units; each w motor units consist of m2 phase armature units; and the m2 phase armature units form a phase armature unit array; the intervals between rows and the intervals between columns are the same; each phase armature unit consists of a phase unit iron core and a phase unit winding; each phase unit iron core with perforations consists of two iron core units, the perforations are formed by overlapping tooth spaces of the two iron core units, two teeth of each iron core unit are arranged along the horizontal direction of a cross section, and a magnet yoke section is connected between the two teeth; a coil is wound into a phase of phase unit winding through the perforations; and the tooth pitch tau a between two adjacent phase unit iron cores along the X direction or Y direction is equal to [1+j/m]] tau p. In addition, the motor has the advantages of simple structure and easy realization of modulization, and the stroke of the motor is not limited.

The invention discloses a voltage amplitude and phase angle measuring method for a double-circuit line non-same-name-phase overline grounded fault point. The method includes the steps that the fault phase voltage, the fault phase current and the zero-sequence current of a protecting and installing position of a circuit line I of a double-circuit line on the same tower are firstly measured; the phase angle of the zero-sequence current of a circuit line II of the double-circuit line on the same tower is calculated, and the zero-sequence current of the circuit line II of the double-circuit line on the same tower is calculated; the voltage amplitude of the double-circuit line non-same-name-phase overline grounded fault point is calculated. Only single-end single-circuit line electric amount is used without introducing the electric amount of the other circuit line, and measurement results are not affected by changes of operation modes of the electric power system. Influence on accuracy of measuring the voltage amplitude of the double-circuit line non-same-name-phase overline grounded fault point by zero-sequence mutual inductance between the lines, transition resistance and a load current is eliminated, and the measuring method is high in measurement accuracy.

The invention provides a wireless charging coil assembly. The wireless charging coil assembly comprises a first wireless charging coil unit and a second wireless charging coil unit, wherein the first wireless charging coil unit comprises a primary side main coil and a primary side secondary coil; the primary side secondary coil and the primary side main coil are connected in series; the second wireless charging coil unit comprises a secondary side main coil and a secondary side secondary coil; the secondary side secondary coil and the secondary side main coil are connected in series; and the first wireless charging coil unit and the second wireless charging coil unit are symmetrically arranged. Compared with the prior art, the wireless charging coil assembly has the following advantages: the primary side main coil and the secondary side main coil adopt a serial dual-rectangular structure having a shape as shown in the specification, so that the transmission efficiency of the coils is effectively improved; the primary side secondary coil and the secondary side secondary coil adopt a serial dual-rectangular structure having a shape as shown in the specification; and therefore, when the coils are used in a multi-inductor resonant circuit, mutual influence between a main inductor and a secondary inductor can be avoided under a condition that the integration degree of the coils is improved.

A magnetic field modulation type flat plate type transverse flux linear motor belongs to the technical field of motors and solves the problem of low thrust intensity of an existing unilateral flat plate type permanent magnet linear synchronous motor. The magnetic field modulation type flat plate type transverse flux linear motor comprises a primary and a secondary, air gaps are arranged between the primary and the secondary, the primary comprises a plurality of phase primary units, each of the phase primary units is composed of a unit primary iron core and a unit primary winding, each unit primary iron core is composed of a plurality of unit primary iron core teeth and a plurality of magnetic partition boards, and the secondary comprises a secondary iron core and a plurality of secondary permanent magnets. The magnetic field modulation type flat plate type transverse flux linear motor improves the thrust intensity, reliability and safety of the motor, eliminates interphase mutual inductance, and enhances control accuracy and dynamical characteristics of current and electromagnetic force of the motor.

The invention discloses an asymmetrical bipolar coil which can be used in a modular wireless power transmission system. The coil is first wound clockwise or counterclockwise from inside to outside orfrom outside to inside to form a rectangle and then wound in the opposite direction from outside to inside or from inside to outside to form another rectangle. Finally, a double-rectangle structure with left and right rectangles is formed, and the left and right sides of the coil are in an asymmetrical form. The asymmetrical form includes at least one case as follows: (1) the left and right sidesof the coil are asymmetric in shape; (2) the left and right sides of the coil are asymmetric in number of turns; and (3) the left and right sides of the coil are asymmetric in line spacing. By adopting the asymmetrical bipolar coil of the invention, the mutual inductance between coils on the same side can be eliminated, which is of great significance to the improvement of the transmission efficiency of the system and the reduction of the control difficulty of the system and is conducive to the development of the modular wireless power transmission system.

The invention discloses an air core coil mutual inductance coefficient error elimination method and application based on a rotation cancellation principle. The method comprises steps of enabling a rotating disc to rotate by 360 DEG/n relative to a current carrying lead, measuring a voltage of an air core coil, rotating the rotating disc by the same degree and measuring a voltage, and performing n times of rotation; obtaining mutual inductance coefficients according to voltage and current values; and performing weighted average of the mutual inductance coefficients to obtain the accurate mutual inductance coefficient value of the air core coil. The invention discloses an air core coil current measurement method. The air core coil mutual inductance coefficient error elimination method is used for obtaining the mutual inductance coefficient, the rotating disc is rotated at the same degree by many times to obtain multiple groups of voltages of the air core coil, currents are obtained according to the mutual inductance coefficients and the voltages, and the accurate value of a tested current is obtained by weighted average of the multiple groups of currents. Under a precondition that factors of the air core coil symmetry, the current carrying lead cross section, the tested current central position and the like are unknown, the instability of the mutual inductance coefficient is reduced, influences on currents can be eliminated, and the measurement accuracy of the air core coil is improved.

The invention discloses a permanent magnet synchronous motor with an interphase uncoupled structure, relating to the field of motors and solving the problem that the control precision of current is influenced because magnetic coupling exists between phases and the defect that stator iron loss is larger because a magnetic circuit passed by magnetic flow generated by electrifying each group of windings is longer. The phase unit of a stator comprises a plurality of phase armature iron cores and a plurality of phase armature windings, wherein each phase armature iron core comprises 2k iron core units; each phase armature iron core is a phase armature iron core with comprises 2k iron core units and has a tooth hole; the tooth hole is formed by superposing tooth slots; the two teeth of each iron core unit are arranged along the axial direction; a magnet yoke section is connected between the two teeth; 2k iron core units are sequentially arranged in a housing case at equal intervals along the peripheral direction; and coils are wounded into single-phase armature windings by tooth holes. The motor has im phase units when being an m-phase motor, and the included angle between the axes of two adjacent phase armature windings is an electrical angle of [(j-1)+(1/m)]*180 degrees. The permanent magnet synchronous motor not only can be used as an electromotor but also can be used as a generator.

The invention discloses a real-time forecasting method and a warning system, wherein an electromagnetic wave field and a temperature field are used for monitoring a water disaster in front of an excavation roadway in a combined mode. The system comprises an explosion-proof main machine 10, an electromagnetic wave emitting coil 1, an electromagnetic wave receiving coil 2 and a thermal infrared temperature sensor probe 4. According to the method, the electromagnetic wave filed and a thermal infrared field are used as signal sources for conducting real-time collection and recording on wave field signals, primary results are obtained after the wave field signals are subject to data processing, a multi-field multi-parameter information fusion judging system is used for conducting fusion, correlation and comprehensive analysis on the processing results of the two kinds of wave field signals, grading and forecasting of water-containing geologic bodies are completed, and according to a set threshold, an intelligent voice alarm conducts alarming on the water-containing geologic bodies reaching the danger level. The real-time forecasting method and the warning system overcome the defect that in the prior art, real-time forecasting cannot be conducted on the water disaster in front of the excavation roadway, fully utilize the advantages of the different physical fields, improve the real-time monitoring and forecasting precision, achieve the purposes of full-process monitoring, and realize real-time forecasting and alarming of the water disaster in front of the excavation roadway.

The invention discloses a modularized wireless charging system for realizing decoupling of double rows of same-side coils. The modularized wireless charging system comprises more than two power transmitters or power receivers, and is characterized in that each power transmitter comprises a driving power supply, a transmitting compensation network and a transmitting coil, the power receiver comprises a receiving coil, a receiving compensation network and a rectifier, the receiving coils or the transmitting coils are placed in a double-row mode, and each receiving coil and/or transmitting coil is correspondingly connected with one or two multi-winding decouplers, so that mutual inductance influence between the receiving coils or the transmitting coils on the same side is eliminated, and decoupling of the receiving coils and/or the transmitting coils is achieved. According to the invention, the modularized wireless charging system can be used for eliminating the mutual inductance influence between the same-side coils, so that the modularized wireless charging system has important significance in improving the transmission efficiency of the modularized wireless charging system and reducing the control difficulty of the system.

The invention discloses a mask type coil device for magnetic resonance imaging of human face tissues and implants, which comprises a soft shell arranged outside a coil body, and the soft shell comprises an upper panel and a lower panel which are the same in material, structure and shape; the upper panel is formed by flexibly bonding six polyimide curved panels through polyurethane rubber, and the six curved panels cover the forehead part, the nose part, the cheek part, the cheek part, the periphery of the lip part and the lower jaw part respectively; nose and eye through holes are formed in the curved plate; the edges of the upper panel and the lower panel are correspondingly connected; the coil body comprises 24 annular coils, and all the coils comprise overlapped parts; the peripheral contour of all the arranged coils is basically consistent with the contour of the soft shell, and the coil body is connected to a magnetic resonance host interface through an external interface board and a radio frequency wire harness. According to the invention, the coil body fits the face of a wearer, and the obtained magnetic resonance imaging has better signal-to-noise ratio and higher image quality.

The invention relates to a transient electromagnetic measurement device and method and a transient electromagnetic measurement airplane. By using a V-shaped planar transmitting antenna with a first included angle, a primary field excited by the transmitting antenna is more beneficial to detection of an upright plate-shaped structure compared with a horizontal primary field excited by traditional transient electromagnetic measurement; moreover, a receiving antenna is arranged on an included angle bisector of the included angle of the transmitting antenna, and the transmitting antenna is used for dividing the receiving antenna into a first part located above the transmitting antenna and a second part located below the transmitting antenna; a magnetic flux of the first part of the receiving antenna and a magnetic flux of the second part of the receiving antenna are equal in size and opposite in direction, so that a total magnetic flux of a primary field of the receiving antenna is zero, mutual inductance between the transmitting antenna and the receiving antenna is effectively removed, and the influence of the primary field on receiving signals of the receiving antenna is eliminated;and the accuracy of a transient electromagnetic measurement result is improved.