31results about How to "Distributed capacitance increases" patented technology

The invention relates to an implanted electrode compatible with MRI. The implanted electrode comprises a flexible insulated conduit, at least one contact, at least one connector and a spiral wire, wherein the flexible insulated conduit is provided with a first end and a second end opposite to the first end, the contacts are arranged on the outer surface of the first end of the flexible insulated conduit, the connectors are arranged on the outer surface of the second end of the flexible insulated conduit, the spiral wire is located in a cavity of the insulated conduit, or located in the wall of the insulated conduit or wound outside the conduit, and the contacts and the connectors are electrically connected through the spiral wire. The spiral diameter of at least one part of the spiral wire is larger than that of the other part of the spiral wire, so that the spiral wire is of a variable spiral diameter structure. The structure can change the electrical parameter performance, under an RF magnetic field of MRI, of the wire, and therefore the heating risk, caused by the RF magnetic field, on the contacts is reduced. The invention further relates to a manufacturing method for the implanted electrode compatible with MRI.

The invention relates to a concomitant impedance protection method for a half-wavelength transmission line. The method comprises the following steps of obtaining three-phase currents and three-phase voltages of the location of a relay protection device at an M side of the half-wavelength transmission line and the location of a relay protection device at an N side of the half-wavelength transmission line separately; judging whether the starting quantities of the M side and the N side meet the starting conditions or not; determining a fault point F according to a time difference that the starting quantities of the M side and the N side meet the starting conditions; and opening the relay protection action of the half-wavelength transmission line according to a concomitant impedance of the half-wavelength transmission line. The method provided by the invention can position the fault by a time-difference method according to the characteristics of a failure period, construct the concomitant impedance by compensating the voltages and the currents at two sides of the line, and correctly reflect an internal fault and an external fault of a line region. Two-terminal electric information is effectively utilized by the concomitant impedance protection, so that the protection can quickly and reliably act after the internal fault of the line region happens; the protection does not move by mistake after the external fault of the line region happens; and the protection has relatively high sensitivity.

The invention relates to a direct-current bus connection structure of a three-phase high-power inverter. In order to solve the problems that the grouping installation of capacitors is not considered in the prior three-phase high-power inverter and the ripple current between the capacitors is reduced, the invention provides a direct-current bus connection structure of the three-phase high-power inverter, which comprises a direct-current power supply, at least two capacitor modules and an inverted switching tube module, wherein the capacitor modules are connected with the inverted switching tube module in parallel, lapped copper bars with vertical laminated structures are arranged between the two adjacent capacitor modules and connected in parallel, and the capacitor modules are connected with the direct-current power supply after being connected with the inverted switching tube module in parallel. By adopting the connection, all the capacitor modules can bear the energy requirement of the entire output power together, and the utilization ratio of the capacitance is improved; the vertical laminated structures of the anode and the cathode copper bars of the capacitor modules, the line impedance and the stray inductance parameter are minimized so as to reduce the ripple current between the capacitor modules; and the capacitor modules adopt the independent structural design, thereby facilitating distributed installation and maintenance.

The invention relates to a rotary transformer with relatively small output common ground error, which is composed of a stator and a rotor and exists in two structural forms, namely, segmental type andintegral type. The stator comprises a stator case, a stator iron core and a stator winding wound thereon, and the rotor comprises a rotor shaft sleeve, a rotor iron core and a rotor winding wound the reon, wherein two phase windings of the rotor winding and / or stator winding are all formed by the alternate arrangement of a circular coil assembly and a concentric coil assembly; and the circular coil assembly and the concentric coil assembly under the two poles of the two phase windings are both symmetrically arranged. The capacitance of the rotary transformer is greatly reduced due to the alternative distribution of the output windings, and the output common ground quadrature error and null voltage are also greatly reduced, thus lowering the system angle measurement error, improving the system precision, and simultaneously widening the excitation frequency application range of the rotary transformer, satisfying the application requirements of certain special systems on high excitation frequency and small output common ground error of the rotary transformer.

The invention discloses an antenna which comprises a first dielectric substrate and a second dielectric substrate, wherein the first dielectric substrate is provided with two opposite side surfaces; a first metal sheet and a feeder that is fed in the first metal sheet in a coupled mode and partially surrounds the first metal sheet are arranged on one side surface of the first dielectric substrate; a second metal sheet is arranged on the other opposite side surface, and is electrically connected with the feeder; the first dielectric substrate is covered with the second dielectric substrate; and a microgroove structure is hollowed on the first metal sheet. According to the antenna, distributed capacitance of the antenna is increased with the adoption of the second dielectric substrate, and an effective radiating area of the feeder is increased with the adoption of the second metal sheet, so that the antenna can work at a very low frequency band, and the miniaturization and the high performance of the antenna can be ensured when the antenna works at the low frequency band. In addition, the invention further discloses an MIMO (multiple input multiple output) antenna provided with the antennas, and the MIMO antenna has high isolation.

The invention discloses a pilot protection method based on discrete Frechet distance of current sampling values on two sides of a line. The method comprises the steps of: in a certain sampling rate, collecting currents at two sides of line protection, and forming current signal sequences I1 and I2; performing normalization processing of the I1 and the I2 to obtain two values as shown in the description and allow the ranges of the two values within the range of [0, 1], employing a Frechet distance algorithm to calculate Frechet distances as shown in the description of current waveform samplingvalues at two sides, and forming an F distance value sequence by promotion point by point according to the time; comparing the calculated and obtained F distance value sequence with a set threshold value Fset, if the F distance value sequence is lower than the threshold value Fset, determining that the line is normally operated or has external faults to perform shutting protection, or else, determining that the line has internal faults to perform action protection. The method can perform accurate determination for various typical faults such as CT saturation and the like, can perform reliableaction and shutting when the waveform is influenced by white noise, and has a high anti-interference capability.

An improved low cost and highly consistent inductive apparatus. In one embodiment, the low cost and highly consistent inductive apparatus addresses concerns with so called conductive anodic filament (CAF) that occurs within these laminate structures. These conditions include high humidity, high bias voltage (i.e. a large voltage differential), high-moisture content, surface and resin ionic impurities, glass to resin bond weakness and exposure to high assembly temperatures that can occur, for example, during lead free solder bonding application. In a variant, mixed mode coupling techniques are utilized in order to extend the underlying operating bandwidth of the substrate inductive device. Methods of manufacturing and using the aforementioned substrate inductive devices are also disclosed.

The invention discloses a radome based on a wide-stop-band low-frequency multi-layer frequency selective surface. The upper surface of the upper PCB board is provided with an upper conductive layer, the lower surface of the upper PCB board is provided with a middle conductive layer, and the lower surface of the lower PCB board A lower conductive layer is provided, the upper conductive layer is composed of several upper interdigital structural units periodically arranged, the middle conductive layer is composed of several cross-shaped structural units periodically arranged, and the lower conductive layer is composed of several lower interdigital structural units periodically arranged. Composed of interdigital structural units, wherein an upper interdigital structural unit corresponds to a cross-shaped structural unit and a lower interdigital structural unit; the upper interdigital structural unit and the lower interdigital structural unit are composed of two comb structures, Among them, the lengths of the outermost teeth of the two comb structures are the same, relatively distributed, and there is a gap between them; each upper interdigital structural unit is completely aligned with the corresponding cross-shaped structural unit and lower interdigital structural unit; the radome has lower resonant frequency.

A large-bandwidth and small-size periodic unit frequency selective surface structure comprises a first base material and a second base material. An upper conducting layer is arranged on the front face of the first base material, a middle conducting layer is arranged between the first base material and the second base material, a lower conducting layer is arranged on the back face of the second base material, and the upper conducting layer, the middle conducting layer and the lower conducting layer are formed by periodically arranging upper periodic units, middle periodic units and lower periodic units respectively, each upper periodic unit is formed by a broken line on the left side and an upper-layer first conducting metal sheet and an upper-layer second conducting metal sheet, wherein the upper-layer first conducting metal sheets and the upper-layer second conducting metal sheets are located on the right side. The middle periodic units are formed by middle-layer conducting metal sheets, each lower periodic unit is formed by a series of lower-layer parallel conducting metal wires, the periodic units on all layers are the same in size and are arranged vertically in an overlapped mode, and the edges of the periodic units are aligned. According to the large-bandwidth and small-size periodic unit frequency selective surface structure, face-to-face coupling of the conducting metal sheets is used, distributed capacitance is enhanced, and the relative size is reduced; the broken lines enhance the distributed capacitance and increase the relative passband bandwidth; the lower-layer parallel conducting metal wires enhance the frequency selective surface cross polarization isolation.

The invention discloses an antenna which comprises a first dielectric substrate and a second dielectric substrate, wherein the first dielectric substrate is provided with two opposite side surfaces; a first metal sheet and a feeder that is fed in the first metal sheet in a coupled mode and partially surrounds the first metal sheet are arranged on one side surface of the first dielectric substrate; a second metal sheet is arranged on the other opposite side surface, and is electrically connected with the feeder; the first dielectric substrate is covered with the second dielectric substrate; and a microgroove structure is hollowed on the first metal sheet. According to the antenna, distributed capacitance of the antenna is increased with the adoption of the second dielectric substrate, and an effective radiating area of the feeder is increased with the adoption of the second metal sheet, so that the antenna can work at a very low frequency band, and the miniaturization and the high performance of the antenna can be ensured when the antenna works at the low frequency band. In addition, the invention further discloses an MIMO (multiple input multiple output) antenna provided with the antennas, and the MIMO antenna has high isolation.

The invention provides an electromagnetic voltage transformer with an insulation function through capacitive impedance epoxy resin casting. The electromagnetic voltage transformer is characterized in that layer insulations with high dielectric constants are adopted, epoxy resin mixtures with high dielectric constants are adopted, the area of a high-low voltage electrostatic screen is increased, the distributed capacitance of the high-low voltage electrostatic screen can be 300-500 pF, and the transformer is still capacitive with perceptual load. The electromagnetic voltage transformer comprises an iron core, a wire wrapping framework, a secondary winding, an inner electrostatic screen, the layer insulation, an outer electrostatic screen and a primary winding. The wire wrapping framework is arranged in the middle of an iron core window, the secondary winding and the primary winding are sequentially wound on the wire wrapping framework from inside to outside, the inner electrostatic screen is arranged on the inner side of the primary winding, the outer electrostatic screen is arranged on the outer side of the primary winding, the layer insulation is arranged between layers of the primary winding, and the iron core, the wire wrapping framework, the secondary winding, the inner electrostatic screen, the layer insulation, the outer electrostatic screen and the primary winding all are arranged in an epoxy resin mixed-casting material layer. The electromagnetic voltage transformer can normally operate under 2.5 times the rated voltage, core saturation is basically avoided, and a ferromagnetic resonance area is avoided.

The invention provides a device for measuring electromagnetic pulse sensitivity of an electric detonator, which includes a pulse source, a first current-limiting power resistor, a second current-limiting power resistor, and a switch; the pulse source includes capacitors C1-C2n, and the capacitors C1-C2n are divided into two Each group includes n capacitors connected in parallel, and the two groups of capacitors are connected in series. One end of the capacitor group connected in series is connected to the first current-limiting power resistor, and the other end of the first current-limiting power resistor is used as the electromagnetic pulse sensitivity measurement device. The positive electrode is used to connect the electric detonator under test; the first current-limiting power resistor is connected to the anode of the switch, and the cathode of the switch is connected to the second current-limiting power resistor, and the other end of the second current-limiting power resistor is used as the electromagnetic pulse sensitivity measurement The negative electrode of the device is used to connect to the electric detonator under test; a certain distance is kept between the anode and the cathode of the switch, and the connection is triggered by the trigger electrode. The device can measure the ignition threshold of the electric detonator in the standard electromagnetic pulse (rising edge<=20ns, pulse width 500ns).

The invention relates to a direct-current bus connection structure of a three-phase high-power inverter. In order to solve the problems that the grouping installation of capacitors is not considered in the prior three-phase high-power inverter and the ripple current between the capacitors is reduced, the invention provides a direct-current bus connection structure of the three-phase high-power inverter, which comprises a direct-current power supply, at least two capacitor modules and an inverted switching tube module, wherein the capacitor modules are connected with the inverted switching tube module in parallel, lapped copper bars with vertical laminated structures are arranged between the two adjacent capacitor modules and connected in parallel, and the capacitor modules are connected with the direct-current power supply after being connected with the inverted switching tube module in parallel. By adopting the connection, all the capacitor modules can bear the energy requirement of the entire output power together, and the utilization ratio of the capacitance is improved; the vertical laminated structures of the anode and the cathode copper bars of the capacitor modules, the line impedance and the stray inductance parameter are minimized so as to reduce the ripple current between the capacitor modules; and the capacitor modules adopt the independent structural design, thereby facilitating distributed installation and maintenance.

The present invention discloses an improved low cost and highly consistent inductive device. In one embodiment, the low cost and highly consistent inductive device solves the problems associated with the so-called conductive anodic filaments CAF that occur within these laminated structures. These conditions include high humidity, high bias voltage (i.e., large voltage differential), high moisture content, surface and resin ionic impurities, glass-to-resin bond weakness, and exposure to high assembly temperatures. In a variant, mixed-mode coupling techniques are utilized in order to extend the fundamental operating bandwidth of the substrate inductive device. The invention also discloses methods of making and using the aforementioned substrate inductive devices.

A frequency selective surface structure of large bandwidth and small size periodic unit, which comprises a first base material and a second base material, the front surface of the first base material is provided with an upper conductive layer, and the first base material and the second base material are provided with The middle conductive layer, the reverse side of the second base material is provided with a lower conductive layer, the upper conductive layer, the middle conductive layer and the lower conductive layer are respectively composed of the upper periodic unit, the middle periodic unit and the lower periodic unit. The broken line on the side and the upper first conductive metal sheet and the upper second conductive metal sheet on the right side are composed of the middle period unit is composed of the middle conductive metal sheet, and the lower period unit is composed of a series of parallel conductive metal wires in the lower layer. Identical and stacked on top of each other, edge-aligned. The frequency selective surface of the present invention uses the surface-to-surface coupling between the conductive metal sheets to increase the distributed capacitance and reduce the relative size; the broken line increases the distributed inductance and increases the relative passband bandwidth; the lower parallel conductive metal lines increase the frequency selective surface crossing Polarization isolation.

The invention relates to an antenna, which comprises a first dielectric substrate, a first metal sheet and a second metal sheet. The first and second metal sheets are attached to the two opposite surfaces of the first dielectric substrate. A first feeder line is arranged in a way of enclosing the first metal sheet. A second feeder line is arranged in a way of enclosing the second metal sheet. The first and second feeder lines feed signals in the first and second metal sheets in a coupling way respectively. A first micro-channel structure is hollowed in the first metal sheet to form first metal wiring on the first metal sheet. A second micro-channel structure is hollowed in the second metal sheet to form second metal wiring on the second metal sheet. The first and second feeder lines are electrically connected. A second dielectric substrate also covers the first metal sheet. According to the antenna, the metal sheets are arranged on the two surfaces of the first dielectric substrate, so that the area of the antenna is fully utilized, the antenna can work at low working frequency in such an environment, and the requirements of miniaturization, low working frequency and broadband multimode for the antenna are met. In addition, the invention also relates to a multiple input multiple output (MIMO) antenna with a plurality of antennae.

The invention relates to a rotary transformer with relatively small output common ground error, which is composed of a stator and a rotor and exists in two structural forms, namely, segmental type andintegral type. The stator comprises a stator case, a stator iron core and a stator winding wound thereon, and the rotor comprises a rotor shaft sleeve, a rotor iron core and a rotor winding wound the reon, wherein two phase windings of the rotor winding and / or stator winding are all formed by the alternate arrangement of a circular coil assembly and a concentric coil assembly; and the circular coil assembly and the concentric coil assembly under the two poles of the two phase windings are both symmetrically arranged. The capacitance of the rotary transformer is greatly reduced due to the alternative distribution of the output windings, and the output common ground quadrature error and null voltage are also greatly reduced, thus lowering the system angle measurement error, improving the system precision, and simultaneously widening the excitation frequency application range of the rotary transformer, satisfying the application requirements of certain special systems on high excitation frequency and small output common ground error of the rotary transformer.

The invention relates to a dual-polarization antenna. The dual-polarization antenna comprises a first dielectric substrate, a first feeder line, a second feeder line, a metal sheet and a second dielectric substrate, wherein the metal sheet is attached to one surface of the first dielectric substrate; the second dielectric substrate covers the metal sheet; the first feeder line and the second feeder line are both fed into the metal sheet in the coupling way; the metal sheet is provided with a microgroove structure in a hollowing way to form a metal route on the metal sheet; and an antenna is previously provided with a space for being embedded by an electric element. According to the dual-polarization antenna disclosed by the invention, the antenna needs to both receive or transmit electromagnetic waves through the second dielectric substrate so that the integral distributed capacitance of the antenna is enlarged, and the working frequency of the antenna can be effectively reduced through the enlargement of the integral distributed capacitance, and therefore, the antenna can still well work at low frequency under the condition that the lengths of the feeder lines are not changed and the requirements of the antenna on small size, low working frequency, wide band and multimode are met. Besides, the invention also relates to an MIMO (Multiple Input Multiple Output) antenna with the dual-polarization antenna.

The invention discloses an antenna housing based on a wide-stop-band low-frequency multilayer frequency selective surface. An upper conductive layer is arranged on the upper surface of an upper-layerPCB; a middle conductive layer is arranged on the lower surface of the upper-layer PCB; a lower conductive layer is arranged on the lower surface of a lower-layer PCB; the upper conductive layer is composed of a plurality of upper interdigital structure units which are periodically arranged, the middle conductive layer is composed of a plurality of cross-shaped structure units which are periodically arranged, the lower conductive layer is composed of a plurality of lower interdigital structure units which are periodically arranged, and each upper interdigital structure unit corresponds to onecross-shaped structure unit and one lower interdigital structure unit; each of the upper interdigital structure unit and the lower interdigital structure unit is composed of two comb tooth structures,the lengths of outermost teeth of the two comb tooth structures are the same, the outermost teeth are oppositely distributed, and a gap is formed between the outermost teeth of the two comb tooth structures; each upper interdigital structure unit is completely aligned with the corresponding cross-shaped structure unit and the corresponding lower interdigital structure unit; and the antenna housing has relatively low resonant frequency.

The invention relates to an accompanying impedance protection method for a half-wavelength transmission line, which includes: separately obtaining the three-phase current and the three-phase current at the installation place of the M-side relay protection device and the N-side relay protection device of the half-wavelength transmission line. voltage; determine whether the start-up quantity on the M side and the N side meets the start-up condition; determine the fault point F according to the time difference between the start-up quantity on the M-side and the N-side to meet the start-up condition; open the relay of the half-wavelength transmission line according to the accompanying impedance of the half-wavelength transmission line protective action. The method provided by the invention can locate the fault by using the time difference method according to the characteristics of the fault period, construct the accompanying impedance by compensating the voltage and current on both sides of the line, and correctly reflect the fault inside and outside the line area, because the accompanying impedance protection effectively utilizes Double-terminal electrical information, so faults within the line area can be quickly and reliably activated, and faults outside the line area will not malfunction, and the protection has high sensitivity.

A distributed inductance and capacitance parameter integrated filter comprises an inner magnetic core and an outer magnetic core which are magnetically conductive, conductive and grounded. One end ofthe inner magnetic core is connected with the outer magnetic core through threads, and the other end of the inner magnetic core is covered with an end cover which is magnetically conductive. The innermagnetic core, the outer magnetic core and the end cover are fixed through screws to form a closed magnetic circuit and an electromagnetic shielding shell. A surface-insulated filter wire penetratesthrough one end of the outer magnetic core and is tightly wound on the inner magnetic core, and grounded wires are wound between turns of the filter wire in parallel to form turn-to-turn isolation wires, so that turn-to-turn capacitive coupling is prevented. And the filtering wire penetrates out of the end cover at the other end. When a multi-layer winding method is adopted, a grounded interlayerisolation metal layer is additionally arranged between layers. According to the invention, the inductance-capacitance formed by the distribution parameters is fully utilized. The adverse effect of distributed capacitance parameters in an original independent inductor on the inductor is overcome; the adverse effect of the distributed inductance parameters in the independent capacitor device on thecapacitor is avoided. The adverse parameters are changed into favorable parameters, the high-frequency performance of the filter is improved, the order of the filter can be reduced, the structure of the filter is simplified, the size of the filter is reduced, and the cost is reduced.

The invention discloses a filter and communication equipment. According to the filter, the structure that a traditional tuning screw extends into a resonance column is improved; the middle part of thetuning screw is hollowed out to form a hollow part, the resonance column protrudes to form a protruding part matched with the hollow part, and the upper end of the protruding part extends into the hollow part, so that the induction area of the tuning screw and the resonance column is increased, equivalently, the distributed capacitance of the resonator is increased, in addition, the size of the filter is effectively reduced, and the cost is reduced.

The invention relates to an implanted electrode compatible with MRI. The implanted electrode comprises a flexible insulated conduit, at least one contact, at least one connector and a spiral wire, wherein the flexible insulated conduit is provided with a first end and a second end opposite to the first end, the contacts are arranged on the outer surface of the first end of the flexible insulated conduit, the connectors are arranged on the outer surface of the second end of the flexible insulated conduit, the spiral wire is located in a cavity of the insulated conduit, or located in the wall of the insulated conduit or wound outside the conduit, and the contacts and the connectors are electrically connected through the spiral wire. The spiral diameter of at least one part of the spiral wire is larger than that of the other part of the spiral wire, so that the spiral wire is of a variable spiral diameter structure. The structure can change the electrical parameter performance, under an RF magnetic field of MRI, of the wire, and therefore the heating risk, caused by the RF magnetic field, on the contacts is reduced. The invention further relates to a manufacturing method for the implanted electrode compatible with MRI.

The invention relates to an antenna, which comprises a first dielectric substrate, a first metal sheet and a second metal sheet. The first and second metal sheets are attached to the two opposite surfaces of the first dielectric substrate. A first feeder line is arranged in a way of enclosing the first metal sheet. A second feeder line is arranged in a way of enclosing the second metal sheet. The first and second feeder lines feed signals in the first and second metal sheets in a coupling way respectively. A first micro-channel structure is hollowed in the first metal sheet to form first metal wiring on the first metal sheet. A second micro-channel structure is hollowed in the second metal sheet to form second metal wiring on the second metal sheet. The first and second feeder lines are electrically connected. A second dielectric substrate also covers the first metal sheet. According to the antenna, the metal sheets are arranged on the two surfaces of the first dielectric substrate, so that the area of the antenna is fully utilized, the antenna can work at low working frequency in such an environment, and the requirements of miniaturization, low working frequency and broadband multimode for the antenna are met. In addition, the invention also relates to a multiple input multiple output (MIMO) antenna with a plurality of antennae.

The invention discloses an antenna which comprises a first dielectric substrate and a second dielectric substrate, wherein a metal sheet and a feeder that surrounds the metal sheet and is fed in the metal sheet in a coupled mode are arranged on the first dielectric substrate; the first dielectric substrate is covered with the second dielectric substrate; and at least one first microgroove structure and one second microgroove structure that are unsymmetrical are hollowed on the metal sheet to allow the antenna to have at least two different resonance frequency bands. According to the antenna, the first dielectric substrate is covered with the second dielectric substrate, so that the miniaturization and the high performance of the antenna can be ensured when the antenna works at a low frequency; the two unsymmetrical microgroove structures are arranged on the metal sheet, so that the antenna at least has two resonance frequency bands; and multiple modes can be achieved easily. In addition, the invention further discloses an MIMO (multiple input multiple output) antenna provided with the antennas, and the MIMO antenna has high isolation.