143results about How to "Lower Q value" patented technology

The invention relates to a local discharge detecting system of a sulfur hexafluoride gas-insulating and fully-enclosed combined electric apparatus. A central control unit thereof is connected with anultrahigh frequency signal receiver and an ultrasonic receiver; if the ultrahigh frequency signal and the ultrasonic wave are measured to have continuous correlation, the position of the ultrasonic receiver on the outer wall of a gas insulating switch device is moved for a plurality of times, a time difference of maximum amplitude occurring in an amplitude characteristic print of the ultrahigh frequency signal and maximum amplitude occurring in an amplitude characteristic print of the ultrasonic wave on all the detecting positions is recorded so as to calculate the distance of a discharge point and all the detecting positions; and then the position of insulation defect in the gas insulating switch device is calculated according to the overall size of the insulating switch device.

The invention discloses a broadband low-section omni-directional circularly polarized antenna. A dielectric substrate of the broadband low-section omni-directional circularly polarized antenna comprises an upper-layer dielectric substrate and a lower-layer dielectric substrate, the upper-layer dielectric substrate and the lower-layer dielectric substrate are parallel to each other, and the upper-layer dielectric substrate is positioned right above the lower-layer dielectric substrate; a metal floor is adhere on the lower-layer dielectric substrate; a zero-order resonator, a parasitic radiator and a radiation type feeding network are adhered on the upper-layer dielectric substrate; the radiation type feeding network is positioned in the center of the upper-layer dielectric substrate; zero-order resonant patches of the zero-order resonator are annularly on the outer side of the radiation type feeding network, one end of each zero-order resonant dowel of the zero-order resonator is connected with the corresponding zero-order resonant patch, and the other end of each zero-order resonant dowel is connected with the metal floor; parasitic radiation patches are annularly arranged on the outer sides of the zero-order resonant patches, one end of each parasitic radiation dowel of the corresponding parasitic radiation patch is connected with the corresponding parasitic radiation patch, and the other end of each parasitic radiation dowel is suspended. The broadband low-section omni-directional circularly polarized antenna has the advantages that impedance of the broadband low-section omni-directional circularly polarized antenna and the bandwidths of directional diagrams can be increased, and excellent axial ratio characteristics can be kept.

The invention provides a method for detecting distortion degree of inrush current of a transformer, which adopts abundant high order harmonic resulting in inrush current distortion in inrush current to comprehensively reflect the distortion degree of the inrush current so as to judge whether fault current or magnetizing inrush current leads the current of the transformer to be abnormal according to the distortion degree. Therefore, the distortion degree Q is defined and the calculation method of Q is declared as follows: filtering out direct current components by a difference algorithm; and filtering out fundamental components by a cosine filter. When the judgment result is the fault current, the numerical values of a front sequence and a rear sequence of the cosine filtering are basicallyconsistent, so the Q value is small; when the judgment result is the magnetizing inrush current, the numerical values of the front sequence and the rear sequence of the cosine filtering have big discrepancy, so the Q value is big. The fault current and the magnetizing inrush current can be strictly distinguished by selecting a valve value properly. The method has higher redundancy on the criterion and can use braking with a logic product door, therefore, differential protection can not act in a delaying manner when being dropped into a transformer in fault. The invention has the advantage ofimproving the condition of low long-term correct action rate of the differential protection of the transformer.

The invention discloses a resonator and a filter. The resonator comprises a substrate, a bottom electrode layer, piezoelectric layers, top electrode layers and a connecting structure, wherein the bottom electrode layer is positioned on the upper side of the substrate; the bottom electrode layer is positioned on the lower sides of the piezoelectric layers integrally or partially; the top electrode layers are positioned on the upper sides of the piezoelectric layers,; and the connecting structure is positioned outside an effective area of the resonator and is in electric contact with the bottom electrode layer and/or the top electrode layers. According to the resonator, the connecting structure is arranged additionally to be connected with at least electrode layer, so that the input impedance of the resonator can be reduced effectively to improve the performance of the resonator and the filter (a Q value of the resonator is prevented from being reduced); and the connecting structure is positioned outside the effective area of the resonator, so that the normal operation of the resonator is not influenced.

An oscillator, comprising: a pair of transistors to which source terminals are interconnected and to which drain and gate terminals are coupled by a positive feedback loop comprising an oscillator tank, wherein the source terminals of the transistors are connected to a current source configured to control physical parameters of the oscillator.

The invention relates to an SIC technology-based four-element dual-polarization microstrip antenna array, which comprises six layers of printed circuit boards and metal supports (6), wherein the lowersurface of a top layer of printed circuit board (17) is printed with rectangular parasitic patches (1); the upper surface of a third layer of printed circuit board (16) is printed with rectangular main patches (2) and a main patch layer reflection plate (11); the upper surface of a fourth layer of printed circuit board (15) is printed with a vertical-polarization feeder line (3) and a ring (8); the upper surface of a fifth layer of printed circuit board (14) is printed with a grounding plate (4); cross gaps (9), circular openings (19) and circular openings (20) are etched on the grounding plate (4); a horizontal-polarization feeder line (5) and a strip line (10) are printed on the lower surface of the fifth layer of printed circuit board (14); and the lower surface of the bottom layer ofprinted circuit board (12) is provided with an antenna bottom reflection plate (13). The SIC technology-based four-element dual-polarization microstrip antenna array has the advantages of wider bandwidth, higher port isolation and lower cross polarization level.

The invention relates to a sulfur hexafluoride gas insulation totally-enclosed combined electric partial discharge detection and positioning system in order to conveniently detect and position the insulation defects of a gas insulation switch device from the outside. A central control unit is connected with an ultrahigh frequency signal receiver and an ultrasonic receiver; if a measured ultrahighfrequency signal and ultrasonic have continuous correlation, the position of the ultrasonic receiver on the external wall of the gas insulation switch device is changed for a plurality of times, and the time difference of maximum amplitude appearing in the amplitude characteristic map of ultrahigh frequency signals and maximum amplitude appearing in the amplitude characteristic map of ultrasonic on each detection position is recorded so as to calculate the distance between a discharge point and each detection position; and the position of the insulation defect in the gas insulation switch device is calculated according to the external dimension of the insulation switch device.

A direct drive type system such as a direct drive type robot is provided. This system includes a rail member, a movable member guided by the rail member and movable along the rail member, and an electric motor to drive the movable member. The system includes a transmission coil and a reception coil. The transmission coil has plural transmission coil segments which are planar coils and arranged on and along the rail member. High-frequency power is supplied to the transmission coil from a power source. The reception coil is arranged on the movable member to be opposed to the transmission coil and configured to an area faced with each of the transmission coil segments, wherein the area is smaller than that of each transmission coil segment. The reception coil receives power from the transmission coil without contact by a magnetic resonance. The received power is supplied to the motor.

The invention relates to gas sensing technologies and particularly relates to a multi-quartz-crystal-oscillator spectral phonometer and a gas detection device employing the same. The gas detection device is used for solving the technical problems of low sensitivity and cumbersomeness in operation of existing gas detection devices. The multi-quartz-crystal-oscillator spectral phonometer comprises a gas chamber, wherein the gas chamber is located outside a multi-quartz-crystal-oscillator assembly, and the bottom of the gas chamber is provided with a hole; an entrance window and an exit window are respectively formed in a sidewall of the gas chamber along a light path; and the entrance window, the multi-quartz-crystal-oscillator assembly and the exit window are located on the same light path. The gas detection device comprises a light source and a light source driver connected with the light source; and a light beam focusing device and the spectral phonometer are sequentially arranged on an exit light path of the light source. The gas detection device further comprises a first phase-locked amplifier and a signal generator which are sequentially connected with each other. According to the spectral phonometer and the gas detection device, through the ingenious arrangement of the multi-quartz-crystal-oscillator assembly, the technical problems in current gas detection that the detection sensitivity is low and the frequency of quartz crystal oscillators is required for being measured frequently are solved.

The invention provides a radiation structure and an array antenna. The radiation structure comprises a radiation fin with a radiation slot in the middle. The radiation slot consists of a transverse slot and a longitudinal slot, which are communicated with each other and are cross-orthogonal. The length of the transverse slot and the length of the longitudinal slot are less than the length of the radiation fin in the extending direction of the corresponding radiation slot. By adding the radiation slot to the radiation fin, the radiation structure can produce two kinds of radiation synchronouslywhen working in an antenna system, so as to achieve an effect of polarization vector superposition enhancement. Thus, the same radiation efficiency and radiation gain of the multi-layer patch structure in the traditional antenna can be achieved by only one layer of radiation fin, fewer components are used, the structure is simple, the antenna profile can be reduced, and antenna miniaturization isfacilitated.

The invention discloses a relativistic klystron amplifier (RKA) output cavity internally installed with a collector. The external diameter of an output cavity nose cone increases gradually from the input direction to the collector connection point. The inner diameter of the collector increases gradually from the output cavity nose cone connection point to the collector main body. The inner wall of an output cavity outer cylinder between supporting pillars and an output cavity end cover is provided with convex bench, and the three supporting pillars are uniformly distributed on the same circumference cross section in the output cavity outer cylinder. According to the relativistic klystron amplifier output cavity, the output cavity Q value is reduced under the condition of not reducing the angular uniformity of the electric field of the output cavity, thereby reducing the electric field intensity in the output cavity, reducing backflow electrons, reducing adverse impact of the backflow electrons on the working stability of a relativistic klystron amplifier, reducing power density of electron beams attacking the inner surface of the collector, reducing the generation of secondary electrons and other impurities, furthermore, preventing the secondary electrons and other impurities from escaping from the collector, and improving the RKA long pulse repeat frequency operation capability.

The invention discloses a thin film volume acoustic wave harmonic oscillator structure and a manufacturing method thereof. The method comprises the steps that a polyimide liquid coating is evenly coated on the surface of an integrated circuit chip directly in a spin mode, then a polyimide layer is formed between the high temperature of 170 DEG C and 250 DEG C in a solidifying mode, a piezoelectric stack structure is deposited on the surface of the polyimide layer, the polyimide layer is used as an acoustic reflecting layer, then interconnected through holes are formed, and the entire thin film volume acoustic wave harmonic oscillator structure and an integrated circuit of the integrated circuit chip are electrically connected through the interconnected through holes. According to the thin film volume acoustic wave harmonic oscillator structure and the manufacturing method thereof, the thin film volume acoustic wave harmonic oscillator structure comprises the integrated circuit chip, the polyimide layer and a piezoelectric stack, the structure is simple and reliable, integrated mechanical firmness is high, sensing is facilitated, and the thin film volume acoustic wave harmonica oscillator structure is applied to radio frequency or sensing systems and is suitable for various complex environments. The manufacturing method of the thin film volume acoustic wave harmonic oscillator structure is simple and quick, the production cycle is shortened, the production cost is lowered, and a good application prospect is achieved.

The invention discloses a method based on split ring resonators (SRRs) for improving impedance matching and expanding frequency band of an annular antenna. The method involves a dielectric substrate, the SRRs, the annular antenna and metal strips, wherein the annular antenna is printed on a part of a region of a front surface of the dielectric substrate, in openings of a loop, the SRRs with appropriate sizes are arranged in an antenna ring, and the metal strips are arranged in the openings of SRRs. The openings in the ring and the built-in SRRs are used for improving impedance matching and expanding frequency points, the impedance bandwidth is expanded by placing the metal strips, and the impedance matching of the annular antenna and the frequency band expansion are perfectly achieved.

The invention provides a millimeter wave omnidirectional circularly polarized antenna used for 5G communication. The millimeter wave omnidirectional circularly polarized antenna comprises a first dielectric plate and a second dielectric plate which are stacked up and down; at least four square parasitic patch units with annular gaps in one diagonal line are printed on the upper surface of the first dielectric plate to form a rotary symmetric structure, and the angles between the adjacent parasitic patch units are equal; a feed network and at least four square radiation patch units with disturbance branches on a pair of opposite corners are printed on the upper surface of the second dielectric plate, and a metal grounding plate is printed on the lower surface of the feed network; each output arm of the feed network comprises a section of tapered gradual change line; the radiation patch units are located under the parasitic patch units; and the diagonal line where the disturbance branches are located and the diagonal line wherein the annular gaps of the parasitic patch units are located are consistent in direction. According to the antenna, high omni-directional circular polarizationcharacteristics can be kept in a 5G communication at 28GHz working frequency band, and the power capacity of the antenna is improved while the D2D communication requirement is met.

The invention discloses a BeiDou microstrip antenna loaded with wrench type resonant rings and relates to a microstrip antenna. The BeiDou microstrip antenna is provided with a medium substrate, upper and lower surface good conductor layers and a coaxial feed structure; the upper and the lower surface good conductor layers are respective coated at upper and lower surfaces of the medium substrate; the upper surface layer is a square patch which is arranged on the middle of the medium substrate; two wrench type resonant rings are symmetrically loaded at a pair of opposite angles of the square patch; each wrench type resonant ring consists of an isosceles-right-triangle-shaped cut corner, a rectangular gap and a circular ring notch groove; the vertex of the isosceles-right-triangle-shaped cut corner is superposed with the vertexes of the selected loading opposite angles; two right-angle sides of the isosceles-right-triangle-shaped cut corner are positioned on two sides, jacked out from the vertexes,. of the square patch; one short side of the rectangular gap is superposed with the inclined side of the isosceles-right-triangle-shaped cut corner; the other short side of the rectangular seam is a chord of the outer circle of the circular ring notch groove; the circle center of the circular ring notch groove is positioned in a position, on a diagonal line of the group of the selected loading opposite angles, of the square patch; and a coaxial inner conductor in the coaxial feed structure is connected with the square patch.

The invention provides technical scheme of a broadband relativistic klystron amplifier. The broadband relativistic klystron amplifier comprises an input cavity, an output cavity, a first intermediate cavity, a second intermediate cavity, a first output transition section, a second output transition section, a collector, a supporting rod, an output coaxial line inner conductor and an output coaxial line outer conductor which are arranged on a drift tube. According to the scheme provided by the invention, the multi-interspace input cavity, two irregular frequency tuning intermediate cavities and the multi-interspace output cavity are adopted, and the bandwidth of the relativistic klystron amplifier can be increased by 10%.

The invention relates to a radio frequency energy acquisition system, and particularly relates to a radio frequency energy acquisition system based on a planar inverted-F antenna. The radio frequency energy acquisition system based on the planar inverted-F antenna comprises an antenna module, an impedance matching network, a boosting circuit, a rectification module and an energy storage module, wherein the antenna module, the impedance matching network, the boosting circuit, the rectification module and the energy storage module are sequentially connected; the antenna module adopts the planar inverted-F antenna; the rectification module comprises a low-pass filter and a full-wave rectification circuit, and the full-wave rectification circuit uses a Schottky diode as the rectification tube. The antenna module acquires electromagnetic waves in the space, the voltage is boosted to the working voltage through the boosting circuit and then inputted to the rectification circuit, DC voltage is then outputted through the filter of the rectification module, and finally, the energy storage module is used for storing the energy. Compared with an energy acquisition system by using an antenna array or other antenna structure, the scheme of the invention can acquire multiple frequencies of electromagnetic waves, and the energy conversion frequency is high.