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33results about How to "Increase mutual inductance" patented technology

Multi-gear fault-tolerance permanent magnetism magnetic flux switching electric machine and fault-tolerance method thereof

InactiveCN101697431AIncrease magnetic circuit permeabilityReduce mutual inductanceMagnetic circuit stationary partsPhysicsMagnetic flux
The invention discloses a multi-gear fault-tolerance permanent magnetism magnetic flux switching electric machine and a fault-tolerance method thereof, belonging to a permanent magnetism fault-tolerance electric machine and a method. The electric machine comprises a salient pole stator, an armature winding and a salient pole rotor. Stator salient poles are E-shaped stator iron blocks; bar-shaped permanent magnets are embedded into a gap between every two E-shaped stator iron blocks in sequence; and stator windings which are coils from a first coil to a sixth coil are wounded on two E-shaped arms connected with the bar-shaped permanent magnets. Since the method employs the multitooth fault-tolerance permanent magnetism magnetic flux switching electric machine, the self inductance of the armature winding is increased; when the multi-gear fault-tolerance permanent magnetism magnetic flux switching electric machine uses high-coercive force permanent magnets, the short circuit current if can be restrained within the rated current iL without considerably increasing the number of turns of the armature winding. The invention has high reliability; the armature magnetic field makes small impact on the permanent magnets; the multi-gear structures of the stator and the rotor of the electric machine enable the electric machine to have small mutual inductance, strong magnetism isolating capability, big electrical inductance, strong capability of restraining the short circuit current and reduced location torque.
Owner:NANJING UNIV OF AERONAUTICS & ASTRONAUTICS

Flexible Rogowski coil used for detecting direct-current system short-circuit current and method for designing same

The invention discloses a flexible Rogowski coil used for detecting the direct-current system short-circuit current and a method for designing the same, the coil comprises a coil and a loop uniformly wound around an annular flexible framework with an opening, an outer layer insulating bush is sleeved outside the coil and the loop, a plug-type interface attached to the coil and the loop is installed on the opening of the annular flexible framework, the coil outgoing line is connected with a sampling resistance module after being educed through the hole of the plug-type interface, the sampling resistance module educes a signal and is connected with a post-integrating circuit. In the Rogowski coil loop winding technique adopted in the invention, the return wire and the coil winding are constituted by one wire. The head end and the tip end of the Rogowski coil are connected by the plug-type interface, which can improve the mechanical life of the Rogowski coil to a great extent, has the advantages of high reliability and convenience for disassembly and installation; the method for designing the Rogowski coil used for detecting the direct-current system short-circuit current can combine the short circuit physical circumstances and the field working condition of the direct-current system.
Owner:XI AN JIAOTONG UNIV

Asymmetric wireless power transmission system with relay coil inserted therein, and method

The invention discloses an asymmetric wireless power transmission system with a relay coil inserted therein, and a method, and relates to the field of a magnetically-coupled resonant wireless power transmission technology. The relay coil and an emission coil are coaxial and are disposed at the same plane. The system and the method mainly solve the problem of low transmission efficiency of a wireless power transmission system whose emission coil is larger than a receiving coil in terms of dimension over an intermediate and long distance. According to the method, through inserting the relay coil which is coaxial and disposed at the same plane with the emission coil in the system, the mutual inductance coefficient between adjacent coils is enhanced, the coupling degree between the coils is improved, the transmission efficiency of the system is improved, the coaxial and same-plane structure of the relay coil and the emission coil helps to save space dimension, and application of the wireless power transmission system in reality is better facilitated.
Owner:CHINA UNIV OF MINING & TECH (BEIJING)

Semiconductor device

A semiconductor device is disclosed including a data family pad layout wherein an effort is made to contrive layouts of a power lead wire and a ground lead wire to minimize effective inductance in priority to a length of a lead wire between a pad and a solder ball land of a semiconductor chip. Pad layouts are arrayed in two rows and one unit of the pad layout is configured such that a data power source and ground are adjacent to each other or one data is inserted between the data power source and the ground. Such configurations decrease mutual inductance between the data power sources and increase mutual inductance between the data power source and the ground causing reduction in effective inductance between the data power source and the ground with the resultant minimization of power and ground noises.
Owner:SEMICON PATENT

Semiconductor device

A semiconductor device is disclosed including a data family pad layout wherein an effort is made to contrive layouts of a power lead wire and a ground lead wire to minimize effective inductance in priority to a length of a lead wire between a pad and a solder ball land of a semiconductor chip. Pad layouts are arrayed in two rows and one unit of the pad layout is configured such that a data power source and ground are adjacent to each other or one data is inserted between the data power source and the ground. Such configurations decrease mutual inductance between the data power sources and increase mutual inductance between the data power source and the ground causing reduction in effective inductance between the data power source and the ground with the resultant minimization of power and ground noises.
Owner:SEMICON PATENT

High speed, low noise, low inductance transmission line cable

A transmission line cable that utilizes a plurality of substantially flat insulated conductors, each consisting of two or more solid metallic strands laid side by side in a parallel configuration within an extruded insulator. The plurality of insulated conductors are stacked into groups of two or more and may be utilized as signal conductors or shield conductors. Once the insulated conductors are stacked, the stack is twisted together, and either wrapped in a conductive insulator, placed in an extruded non-conductive insulator, or both, creating a cable that is stable, flexible, and has improved transmission characteristics, including reduced attenuation, noise and signal skew.
Owner:WIREWORLD BY DAVID SALZ

Device used for measuring distance between moving object and its railway

The invention discloses a distance between a moving object and the track detecting device. A high frequency signal source, a transducer and a signal processing circuit of the detecting device are arranged in a moving object. Wherein, the transducer is constituted by an induction winding and the length of the induction winding along the track is equal to or is integer times as much as one longitudinal interval of the periodic variation of the track magnetic resistance or track resistance. The device is suitable for the distance detection between a maglev-vehicle and the track and can not be affected by the track magnetic resistance variation. The device has the advantages of high detection accuracy, all components of the device being arranged on the moving object, less quantity of components, low cost and easy maintenance.
Owner:SOUTHWEST JIAOTONG UNIV

Micro-fluidic chip

The invention discloses a micro-fluidic chip. The micro-fluidic chip comprises a matrix, a solenoid coil, a solenoid coil lead and a glass slide, wherein an L-shaped flowing pass is arranged inside the matrix; a flowing pass inlet is formed in the left side of the flowing pass; a flowing pass outlet is formed in the right side of the flowing pass; the central section of the flowing pass is a signal detecting area; the solenoid coil is twined at the central part of the signal detecting area, adopts a twin coil structure and adopts a double strand enameled wire for twining; the two coils are the same in the twining direction and in the current direction and twined in a parallel manner; one end of the solenoid coil lead is connected with the solenoid coil and the other end of the solenoid coil lead is led out of the matrix. According to the invention, a twin coil solenoid sensor solves the problem that the conventional unicoil sensors are unstable in electrical property and is easily disturbed by environment; when the self-inductance of the two coils can be greatly reduced through mutual inductance; the micro-fluidic chip is very good in detectability and detecting accuracy for smaller particles and ferromagnetic particles smaller than 10 micrometers can be detected; in addition, the length of a detecting coil doesn't need to be increased, and the possibility that particles to be detected enter the detecting area can be greatly lowered.
Owner:DALIAN MARITIME UNIVERSITY

Contactless power supply system transmitting end unit and contactless power supply system transmitting end

The invention relates to the technical field of non-contact power supply, and provides a non-contact power supply system transmitting end unit and a non-contact power supply system transmitting end. The transmitting end unit of the non-contact power supply system comprises a converter and a branch compensator, each converter is connected with a plurality of first output cables, and the branch compensator comprises an access end, wherein the access end is connected with the first output cables of at least two converters, and is divided into two second output cables through the branch compensator. Two second output cables of each branch compensator are connected to both ends of a transmitting coil. As that current output from different converter of the same power supply unit is couple through different transmitting coil loops, at that same time, the mutual inductance between different transmit coil loops is reduce, which can reduce the problem of current imbalance in the transmitting coil loop and improve the transmitting efficiency of the system. In addition, the non-contact power supply system transmitting end includes the above non-contact power supply system transmitting end unit.
Owner:CRRC QINGDAO SIFANG CO LTD

Transformer

The invention provides a transformer, which comprises a magnetic core assembly, a primary winding and a secondary winding, wherein the primary winding and the secondary winding are wound on the magnetic core assembly and are matched with the magnetic core assembly to be used, the primary winding comprises a first winding and a second winding, the first winding is coupled with the secondary winding in the axial direction, the second winding is coupled with the secondary winding in the radial direction, and / or the secondary winding comprises a third winding and a fourth winding, wherein the third winding is coupled with the primary winding in the axial direction, the fourth winding is coupled with the primary winding in the radial direction. Through the technical scheme of the transformer, the primary winding and the secondary winding in the transformer can be coupled in both the axial direction and the radial direction, in addition, the production cost of the transformer is reduced, and the heat radiation effect of the transformer is optimized.
Owner:MIDEA GRP CO LTD +1

Double-L shaped current sharing stress-resistant IGBT (insulated gate bipolar transistor) module busbar terminal

The invention discloses a double-L shaped current sharing stress-resistant IGBT module busbar terminal which comprises an emitting electrode busbar and a collecting electrode busbar, wherein two L-shaped first pins are arranged below the emitting electrode busbar; two L-shaped second pins are arranged below the collecting electrode busbar; and the two L-shaped first pins and the two L-shaped second pins are positioned on an identical line when being welded. The terminal has the advantages of simple and compact structure, low cost, convenience in operation, good current sharing property, stress resistance and the like.
Owner:ZHUZHOU CSR TIMES ELECTRIC CO LTD

Novel power module of packaging structure

PendingCN108598074AReduce package inductanceIncrease package inductanceSemiconductor/solid-state device detailsSolid-state devicesVoltage overshootCoupling
The invention discloses a novel power module of a packaging structure. The power module comprises a first direct-current side terminal, a second direct-current side terminal, an alternating-current side terminal, a first drive terminal, a second drive terminal, a first silicon carbide metallic oxide semiconductor field-effect tube, a second silicon carbide metallic oxide semiconductor field-effecttube, a diode and a base, wherein the first direct-current side terminal, the second direct-current side terminal, the alternating-current side terminal, the first drive terminal and the second driveterminal are arranged on the upper surface of the base; and the first direct-current side terminal and the second direct-current side terminal are positioned on the same axis. According to the direct-current side terminals of coaxial structures provided by the invention, the distance between the direct-current side terminals can be reduced effectively, the coupling area is increased, the mutual inductance of the direct-current side terminals is increased, the packaging inductance of the power module is reduced, the voltage overshoot of the silicon carbide MOSFETs inside the power module in switching transient and short-circuited conditions is further reduced, and the switching loss of the power module is reduced.
Owner:NORTH CHINA ELECTRIC POWER UNIV (BAODING)

Laminated structure of radio frequency transformer

The invention discloses a laminated structure of a radio frequency transformer, which consists of three metal coil layers which are laminated and include a top metal coil layer, a middle metal coil layer and a bottom metal coil layer. The top metal coil layer is used as secondary metal for realizing mutual inductance, the middle metal coil layer is used as primary metal for realizing mutual inductance, and the bottom metal coil layer is used as secondary metal for realizing mutual inductance. The top metal coil layer, the middle metal coil layer and the bottom metal coil layer are provided with metal coil graphics in a plane, the coil graphics of each metal coil is in set width, the head ends and the tail ends of the top metal coil layer and the bottom metal coil layer are connected with the middle metal coil layer through through-holes among layers or stripped layers, so that parallel connection structure of the metal coils is realized. Since the primary metal coil and secondary metal coil are in laminated structures, restraint of structure design rules in the plane can be avoided, distance between the primary coil and the secondary coil is reduced, coupling between the primary metal coil and the secondary metal coil is improved effectively, and mutual inductance between the primary metal coil and the secondary metal coil is improved as well.
Owner:SHANGHAI HUAHONG GRACE SEMICON MFG CORP

Single-ended inductor

The invention discloses a single-ended inductor. A metal coil of the single-ended inductor is of a planar spiral winding structure, the metal width of the metal coil gradually increases from the inner circle to the outer circle. Under high frequency, the skin depth of all positions near the inner circle is smaller than the skin depth of the outer circle, so that after the metal width near the inner circle is reduced, the resistance in all positions near the inner circle will not increase, and current of the metal coil will not be lowered. Meanwhile, after the metal width near the inner circle is reduced, effective average distance between every two adjacent metal wire sections of the metal coil is reduced, the mutual inductance between every two adjacent metal wire sections of the metal coil increases, and therefore the inductance of the single-ended inductor can be improved.
Owner:SHANGHAI HUAHONG GRACE SEMICON MFG CORP

Electrical eddy current electro-mechanical transformation apparatus and method

The present invention discloses an electrical eddy current electro-mechanical transformation apparatus and method. The electrical eddy current electro-mechanical transformation apparatus comprises a partially metallized disk, a printed circuit board, several induction coil pairs, an excitation device, and a measurement apparatus. The partially metallized disk is suitable for connecting to an external to-be-detected rotating part and synchronous rotation. The printed circuit board and the partially metallized disk are disposed in parallel and opposite to each other. The induction coil pair comprises a primary coil and a secondary coil. The primary coil and the secondary coil are separately coaxially disposed on both sides of the printed circuit board, and a central axis of each induction coil pair is parallel to a central axis of the partially metallized disk. The excitation device is electrically connected to the primary coil, and the secondary coil is electrically connected to the measurement apparatus. The primary coil and the secondary coil are coupled by means of a mutual induction effect. The measurement apparatus outputs a measurement signal according to an induction amount variation of the secondary coil. The electrical eddy current electro-mechanical transformation apparatus is simple in structure and convenient for installation. Further, a coefficient of mutual induction between the primary coil and the secondary coil is large, and power consumption is low.
Owner:NINGBO WATER METER

Novel direct-current busbar

The present invention discloses a novel direct-current busbar. The novel direct-current busbar comprises absorption capacitors, energy storage capacitors, a positive pole, a negative pole and an insulating layer; the plurality of energy storage capacitors are arranged to form a ring-shaped structure; the plurality of the energy storage capacitors are connected in parallel; the positive pole is connected with one end of each of the energy storage capacitors; the other ends of the storage capacitors are connected with the negative pole; the insulating layer is stacked on the positive pole; the negative pole is stacked on the insulating layer; the plurality of absorption capacitors are arranged to form a ring-shaped structure; the absorption capacitors are located on the negative pole; the absorption capacitors are used for decreasing parasitic inductance; the plurality of absorption capacitors are connected in parallel; and the storage capacitors are connected in parallel with the absorption capacitors. With the novel direct-current busbar provided by the invention adopted, parasitic inductance in a power loop can be effectively decreased, and therefore, voltage and current overshoot of a silicon carbide power device during a switching process can be decreased, switching loss can be reduced, and the service life of the silicon carbide power device can be prolonged.
Owner:NORTH CHINA ELECTRIC POWER UNIV (BAODING)

Ultrahigh-voltage air-core reactor

The invention discloses an ultrahigh-voltage air-core reactor which comprises a coil, a grading ring and a support insulator, wherein the coil comprises an upper coil, a lower coil, an insulating layer and at least two wiring terminals, a nut at the lowermost end of the upper coil and a nut at the uppermost end of the lower coil need to be connected through a connecting rod to connect the upper coil and the lower coil in series. The coil is of an inner shielding type winding structure, and at least two wiring terminals are connected to the side face of the outer ring of the winding, penetratethrough the insulating layer, extend to the outer side of the winding and are fixed to the supporting plate to facilitate external wiring. The coil clamping device comprises an upper star-shaped frame, a lower star-shaped frame and a connecting component, the upper star-shaped frame and the lower star-shaped frame are installed at the upper end and the lower end of the coil respectively and connected through the connecting component to vertically clamp the coil, and the rigid connecting component supports the coil on the inner wall of the coil by a circle to integrally form a stable structure.The reactor is compact and novel in structure, small in size, light in weight, good in heat dissipation effect, high in withstand voltage, capable of achieving multi-capacity service, small in installation space and high in practicability.
Owner:顺特电气设备有限公司

Flexible Rogowski coil used for detecting direct-current system short-circuit current and method for designing same

The invention discloses a flexible Rogowski coil used for detecting the direct-current system short-circuit current and a method for designing the same, the coil comprises a coil and a loop uniformly wound around an annular flexible framework with an opening, an outer layer insulating bush is sleeved outside the coil and the loop, a plug-type interface attached to the coil and the loop is installed on the opening of the annular flexible framework, the coil outgoing line is connected with a sampling resistance module after being educed through the hole of the plug-type interface, the sampling resistance module educes a signal and is connected with a post-integrating circuit. In the Rogowski coil loop winding technique adopted in the invention, the return wire and the coil winding are constituted by one wire. The head end and the tip end of the Rogowski coil are connected by the plug-type interface, which can improve the mechanical life of the Rogowski coil to a great extent, has the advantages of high reliability and convenience for disassembly and installation; the method for designing the Rogowski coil used for detecting the direct-current system short-circuit current can combine the short circuit physical circumstances and the field working condition of the direct-current system.
Owner:XI AN JIAOTONG UNIV

A pcb rogowski coil for measuring the chip current of crimping igbt module

The invention discloses a PCB Rogowski coil for measuring a chip current of a pressure-welding IGBT module. The PCB Rogowski coil comprises a circular PCB base plate, boss penetrating holes and measuring coils, the multiple boss penetrating holes are distributed on the circular PCB base plate, distribution positions and sizes correspond to boss structures in the pressure-welding IGBT module, the measuring coils form multi-turn coil structures uniformly distributed around the boss penetrating holes through upper and lower routings and through holes of the circular PCB base plate, the PCB Rogowski coil is embedded between the boss structures in the pressure-welding IGBT module and superposed on a grid electrode routing PCB in the pressure-welding IGBT module, and when a changing current flows through a boss branch circuit, an induction potential is generated at the corresponding measuring coil, and the current change of the boss branch circuit is obtained through integral conversion of the induction potential. According to the PCB Rogowski coil, the current of the branch circuit at any position can be measured, the measuring precision of the current is improved, the operation is simple, and the current measuring cost of the parallel-connected branch circuits of the pressure-welding IGBT module is greatly reduced.
Owner:HUAZHONG UNIV OF SCI & TECH

Coplanar wireless power transmission system for enhancing mutual inductance by applying soft magnet

The invention discloses a coplanar wireless power transmission system for enhancing mutual inductance by applying a soft magnet. The coplanar wireless power transmission systemstructure is characterized in that the structure comprisesby comprising an inversion alternating current power supply, one or more receiving ends, a plurality of LC resonators and a plurality of groups of soft magnet structures., the The LC resonators are connected through the soft magnets, the inversion alternating current power supply is connected to the first LC resonator, the receiving end is connected to the last LCresonator, and a chain-shaped or tree-shaped coplanar structure is formed. The structural section is small; according to the utility model, the coplane can be realized, the mutual inductance betweenadjacent coils is enhanced, the transmission efficiency is greatly improved, and the cross mutual inductance between non-adjacent coils is effectively inhibited and is generally 1-2 orders of magnitudes smaller than that of main coupling, so that the electric energy multipath transmission caused by cross coupling in the system can be ignored , and the design difficulty is reduced.
Owner:NANCHANG UNIV

Bowl-shaped wireless charging device with high charging efficiency

The invention discloses a bowl-shaped wireless charging device with high charging efficiency, and relates to the technical field of wireless transmission. The device comprises a bowl-shaped vessel body, a transmitting coil group and a charging control circuit, the charging control circuit is connected with the transmitting coil group, the bowl-shaped vessel body comprises a bottom surface in the shape of a regular N polygon and N side surfaces in the shape of an isosceles trapezoid, the bottom transmitting coil is of a regular N polygon and is arranged in the bottom surface of the bowl-shaped vessel body, the N side transmitting coils are of isosceles trapezoid structures and are arranged in the side surfaces of the bowl-shaped vessel body respectively, the bottom transmitting coil is connected with one of the side transmitting coils in series, and every two adjacent side transmitting coils are connected in series reversely. According to the connection method, the self-inductance of the transmitting coil and the mutual inductance between the receiving device and the transmitting device are increased, so that the transmission power and the transmission efficiency of the system can be maximized under the condition of the same input voltage of the device.
Owner:JIANGNAN UNIV

Laminated structure of radio frequency transformer

The invention discloses a laminated structure of a radio frequency transformer, which consists of three metal coil layers which are laminated and include a top metal coil layer, a middle metal coil layer and a bottom metal coil layer. The top metal coil layer is used as secondary metal for realizing mutual inductance, the middle metal coil layer is used as primary metal for realizing mutual inductance, and the bottom metal coil layer is used as secondary metal for realizing mutual inductance. The top metal coil layer, the middle metal coil layer and the bottom metal coil layer are provided with metal coil graphics in a plane, the coil graphics of each metal coil is in set width, the head ends and the tail ends of the top metal coil layer and the bottom metal coil layer are connected with the middle metal coil layer through through-holes among layers or stripped layers, so that parallel connection structure of the metal coils is realized. Since the primary metal coil and secondary metal coil are in laminated structures, restraint of structure design rules in the plane can be avoided, distance between the primary coil and the secondary coil is reduced, coupling between the primary metal coil and the secondary metal coil is improved effectively, and mutual inductance between the primary metal coil and the secondary metal coil is improved as well.
Owner:SHANGHAI HUAHONG GRACE SEMICON MFG CORP

Low-inductance silicon carbide module

The invention relates to the technical field of silicon carbide semiconductor modules, in particular to a low-inductance silicon carbide module. The module comprises a current input terminal, a firstceramic copper-clad plate, a ceramic chip, a second ceramic copper-clad plate, a heat dissipation bottom plate, a current output terminal, a chip and a metal connecting block; the current input terminal and the current output terminal are parallel to the first ceramic copper-clad plate and are supported by the metal connecting block, and the chip is welded between the first ceramic copper-clad plate and the metal connecting block and is bonded with the current input terminal and the current output terminal through the metal connecting block; the ceramic chip is welded to the back face of the first ceramic copper-clad plate and connected with the second ceramic copper-clad plate, and the second ceramic copper-clad plate is connected with the heat dissipation bottom plate. According to the invention, the over-current capability and the heat conduction capability of the connecting device can be improved; the metal connecting block is large in cross sectional area and not prone to deformation under the action of external force, and reliability is improved; the inductance of the module is reduced, and current output capability and service life of the module are improved.
Owner:MACMIC SCIENCE & TECHNOLOGY CO LTD

Magnetic resonant wireless energy transmission system based on SS topology

The invention provides a wireless energy transmission system based on SS topology. The system is used for solving the technical problems that efficiency is low and a system is complicated when a loadis large in the prior art. The system comprises an input power module composed of a mains input module and a DC_DC voltage reduction module jointly, a primary inversion module, a primary impedance matching module, a WPT module, a secondary impedance matching module and a secondary rectifying and filtering module. According to the system, by designing the structure that a primary coil and a secondary coil in the WPT module are formed after wires are spirally wound around the bottoms of two U-shaped magnetic cores with openings arranged oppositely and by designing the secondary impedance matching module to match output impedance of the WPT module to reach an optimal load point, the transmission efficiency of the system is improved. Besides, the primary impedance matching module is designed to improve output impedance of the primary inversion module, the input power module consisting of the DC_DC voltage reduction module and the mains input module is applicable and replaces a complicateddirect-current voltage-stabilized power module or a transformer-contained switching power module, and therefore the system is simplified.
Owner:XIDIAN UNIV

Differential eddy current resonance detection sensor and system

The invention discloses a differential eddy-current resonance detection sensor and system, and belongs to the technical field of nondestructive testing, the differential eddy-current resonance detection sensor comprises an excitation coil and a receiving coil which are coupled, the receiving coil is connected with a first resonant capacitor in parallel, and the excitation coil is connected with a second resonant capacitor in parallel, so that an excitation loop and a detection loop reach a resonant state respectively; and the mutual inductance of the exciting coil and the receiving coil is enhanced, and the coil voltage when the defect is detected is enhanced, so that the related defect information of the tested piece is detected, and the defect detection capability is improved. Furthermore, the excitation coil and the receiving coil are connected with a resonant capacitor in parallel, so that the coupling relation between the excitation coil and the detection coil is changed, mutual inductance between the coils is increased, the optimal excitation frequency is reduced, the skin depth of eddy current is increased, and the detection capacity for deep defects is improved.
Owner:SICHUAN DEYUAN PETROLEUM & GAS CO LTD
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