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

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.