42results about How to "Wide measurement frequency range" patented technology

The invention relates to a broadband online measurement sensor for DC extra-high voltage corona current, which comprises an isolation electrode unit, a signal processing unit and a system power supply unit, wherein the isolation electrode unit comprises an insulated isolation sleeve, a hollow tubular long arm low-voltage electrode and a hollow tubular short arm high-voltage electrode, wherein two ends of the insulated isolation sleeve are respectively in security isolation connection with the high-voltage electrode and the low-voltage electrode in a special way; the signal processing unit consists of a sampling resistor module, a signal acquisition module, a signal conversion module and a signal transmission module; the system power supply unit comprises a storage battery pack and a charging module; and the signal processing unit and the system power supply unit are arranged in the isolation electrode unit, so that the high-accuracy integral measurement sensor can be formed. The broadband online measurement sensor solves the problems of shielding disturbance of a strong electric field between an acquired signal and an acquisition channel as well as surrounding stray capacitance, and realizes the broadband domain online measurement and the multi-point network online measurement of the DC extra-high voltage corona current.

The invention discloses an electromagnetic interference monitoring and identification method for a power LTE wireless private network. The method comprises two processes: spectrum monitoring and interference identification. The spectrum monitoring comprises the steps: employing a scanning heterodyne type frequency spectrum monitoring design at a high frequency band; through multi-stage frequency conversion processing, converting an input signal to a lower intermediate frequency, and then adopting a Fourier spectrum monitoring design at a middle frequency band to perform A/D sampling quantification on the signal which is converted to the intermediate frequency, converting the signal into a digital signal, and then employing a digital intermediate frequency technology and Fourier transform to complete spectrum monitoring. The interference source identification process comprises the following steps: firstly, performing preprocessing, feature extraction and feature selection on acquired data, learning a relationship between acquired signal features and an interference source by utilizing a machine learning algorithm to obtain a classification model based on interference source identification, extracting features from a test signal, and identifying a result by adopting the obtained classification model. According to the invention, frequency spectrum monitoring and interference identification functions of the electromagnetic frequency spectrum can be tightly combined according to the requirements of a power system, and the method is suitable for a 1.8 GLTE wireless private network.

The invention provides a single-port coaxial line complex permittivity measuring device and a method based on mode matching. The single-port coaxial line complex permittivity measuring device comprises a coaxial line cable connector, a coaxial waveguide section and a terminal short circuit metal plate, wherein the coaxial line cable connector, the coaxial waveguide section and the terminal short circuit metal plate are connected in sequence, the lateral dimension of the coaxial waveguide section is not dependent on the size of the coaxial line cable connector, and the coaxial waveguide section works in a multimode state. The measuring method relates to the measuring device and a vector network analyzer. A reflection coefficient of a sensing device which is filled in substance to be measured is measured through the vector network analyzer and then through data processing, a complex permittivity of the substance is achieved through inversion. Due to the fact that a multimode matching model is used in the inversion process, the coaxial waveguide section can works in the multimode state, so that the design and processing demands of measuring and sensing devices are lowered and an upper limit of working frequency is improved.

The invention provides an anti-noise wide-range frequency measurement method, which comprises 1 estimating frequency range of measured signals which are digital signals; 2 receiving the measured signals, within the estimated frequency range, sequentially changing frequency values, searching the frequency value which enables degree of correlation of reference signals and the measured signals to be maximum, and taking the frequency value as the frequency value of the measured signals. Signal pattern of the reference signals is the same as that of the measured signals. The invention further provides a corresponding anti-noise wide-range frequency meter, which has strong anti-noise capability, and is capable of accurately measuring signals with low signal to noise ratio and wide in measurable frequency range. In addition, apart from being capable of measuring frequency of signals, the anti-noise wide-range frequency meter is also capable of measuring phase and amplitude of signals synchronously.

The invention provides a flexible hinge beam fiber Bragg grating two-dimensional acceleration sensor. One side of the base is provided with a support base which is connected to a cylindrical flexible hinge beam by using a screw. A measurement groove is processed in the circumferential direction of the flexible hinge beam, and the depth of the measurement groove is smaller than the radius of the flexible hinge beam. Two fiber mounting grooves are processed along the axial direction at the outer surface of the flexible hinge beam. The angle between the sections where two fiber mounting groove center lines are located is 90 degrees. Fiber Bragg gratings are bonded in the fiber mounting grooves by using glue, and the grating parts of the fiber Bragg gratings are above the measurement groove. The flexible hinge beam fiber Bragg grating two-dimensional acceleration sensor of the invention has the advantages of high temperature resistance, a simple structure, easy manufacture, a small size and easy going down and can be used in the fields of downhole seismic wave exploration and micro-seismic monitoring technology.

The invention discloses a photoelectric detector frequency response measurement method and a measurement system thereof and belongs to the photoelectric device measurement and microwave photonics technology field. In the invention, an intensity modulator is adopted to modulate a microwave signal to a optical carrier wave, after proper direct current bias, an optical double-sideband detecting signal which restrains the carrier wave is generated. An optical beam splitter divides an optical signal into two paths. One path of the optical signal is input into an optical power meter so as to detect optical power and the other path of the optical signal is input into a photoelectric detector to be measured. A microwave power meter measures power of a microwave signal output by the photoelectric detector to be measured. Frequency scanning is performed on the microwave signal so that changing curves of optical power of an optical detection signal and microwave signal power output by the photoelectric detector along with frequencies can be acquired. According to a photoelectric detector frequency response definition, a frequency response curve of the photoelectric detector to be measured can be acquired. The invention also discloses a photoelectric detector frequency response measurement system. Compared to the prior art, a measurement range is expanded and measurement precision and efficiency are increased.

The invention discloses a device and a method for simultaneously measuring the frequencies of multiple microwave signals. An upper side-band optical signal including the frequency of a to-be-measuredmicrowave signal is obtained through a modulator and a filter and sent to dispersion shifted fibers. When the frequency difference of laser signals input to the two ends of any dispersion shifted fiber is Brillouin frequency shift, part of energy of a laser signal output by a corresponding single-frequency laser is transferred to the upper side-band optical signal. A data processor measures the output current of a low-frequency photoelectric detector under the condition that the to-be-measured microwave signal is not added and the output current of the low-frequency photoelectric detector under the condition that the to-be-measured microwave signal is added, and compares the currents. If the output current of the low-frequency photoelectric detector under the condition that the to-be-measured microwave signal is added is larger, the to-be-measured microwave signal contains a microwave signal of a corresponding frequency. If the output current of the low-frequency photoelectric detectorunder the condition that the to-be-measured microwave signal is added is unchanged or smaller, the to-be-measured microwave signal does not contain a microwave signal of a corresponding frequency. Multiple microwave frequencies can be instantaneously measured. Moreover, the measurement frequency range is wide, and the measurement resolution is as high as 0.1GHz.

The invention provides a power semiconductor module for integrating a magnetic core of a current sensor. The power semiconductor module comprises an output electrode, a sampling control terminal, a bottom plate, a ceramic substrate and a shell, wherein the output electrode is connected with an output electrode arm which is arranged parallel to the direction of the bottom plate; the output electrode arm is connected with the ceramic substrate; a magnetic core of a sensor sleeves the output electrode arm, and is provided with an upward magnetic core opening; and a jack is formed in the corresponding position, above the magnetic core opening, of the shell. The magnetic core of a current sensor is integrated inside the power semiconductor module, a Hall element is needed to be inserted into the magnetic core opening when current sampling is needed, the step of assembling the current sensor outside the power semiconductor module in the prior art is reduced, the integration degree, the miniature degree and the stability of the control system can be improved, and the subsequent using cost is reduced.

The invention provides a numerically-controlled machine tool energy consumption data test and analysis device and method and belongs to the technical field of energy consumption test. An energy consumption data acquisition device can be used for testing power and energy consumption of a numerically-controlled machine tool in real time through simple operation. The technical scheme includes that the energy consumption data acquisition device comprises circuit boards, current sensors, voltage sensors, precision resistors, a socket, data acquisition cards, a sensor power supply, an external casing and a computer; circuits connected with the current sensors, the voltage sensors, the precision resistors and the sensor power supply are used for testing current and voltage of the numerically-controlled machine tool, the data acquisition cards and the external casing are used for acquiring data of tested current and voltage, and the computer can be used for processing the acquired data to acquire real-time energy consumption data of the machine tool and storing the real-time energy consumption data in a database. The energy consumption acquisition device is high in sampling frequency, large in test range, high in test precision, moderate in price, simple in structure, convenient in use, capable of monitoring power and energy consumption of various machine tools and wide in applicationprospect in terms of low carbon and energy consumption.

The invention provides a flexible structure three-dimensional form inversion method based on PSD optical measurement. The relative displacement of a feature point of a flexible structure is measured by utilizing a laser position sensor PSD, and meanwhile, a gyroscope is used for measurement and integration to obtain a corresponding structure rotation angle, so that the displacement is corrected; by using structural modal vibration type information obtained by pre-analysis of a finite element or a test method, the three-dimensional form of the whole flexible structure is obtained through vibration type superposition inversion. Compared with a traditional form inversion method based on optical fiber or other optical measurement means, the method has the advantages that the number of measuring points is small, the measuring frequency band is wide, distribution is easy, and an inverse algorithm is simple.

The invention discloses a device for measuring capacitance (C) and equivalent series resistance (ESR) in a large frequency range. The device for measuring the capacitance (C) and the ESR in the largefrequency range comprises a square wave generating circuit, a capacitor to be tested, a direct current voltage source and a power load resistor. One end of a first capacitor in the square wave generating circuit is connected with the negative input end of an operational amplifier, the other end of the first capacitor in the square wave generating circuit is a reference potential zero point, one end of a feedback resistor is connected with the negative input end of the operational amplifier, after the first resistor and a second resistor are connected in series, the common end is connected withthe positive input end of the operational amplifier, the other end of the first resistor is simultaneously connected with the feedback resistor and a third resistor, the second resistor is connectedwith the reference potential zero point, the other end of the third resistor is connected with the output end of the operational amplifier, after a first voltage stabilizing diode and a second voltagestabilizing diode are connected in series, one ends of the first voltage stabilizing diode and the second voltage stabilizing diode are connected with the common point of the first resistor and the third resistor, and the other ends of the first voltage stabilizing diode and the second voltage stabilizing diode are connected with the reference potential zero point. The device for measuring capacitance (C) and ESR in the large frequency range can accurately measure values of the capacitance (C) and the ESR, and has simple circuit structure, low cost and large measuring frequency range.

The invention relates to a six degrees of freedom vibration acceleration measurement device, used for measurement of multidimensional vibration quantity in the complex vibration environment and structural multidimensional vibration analysis. The device has an integrated space adapter, four three-dimensional acceleration sensors and a counterweight. The four three-dimensional acceleration sensors are installed on a vertical branch bream and three horizontal branch beams of the space adapter respectively, wherein the rear part extension end of one horizontal branch beam is provided with the counterweight, so as to adjust the geometric symmetry of the measurement device relative to a vertical central axis, and the lower end of the vertical branch bream is fixed on a pedestal. The six degrees of freedom vibration acceleration measurement device designed by the invention has many advantages such as wide measuring frequency range, light weight, convenient installation and high precision, and has wide application prospect in engineering.

The invention provides an on-line inter-harmonic wave monitoring method and device. The method comprises the following steps: an acquired three-phase voltage signal is interpolated, the amplitude of the interpolated voltage in each frequency band is calculated, and inter-harmonic wave monitoring operation is performed based on the amplitude. On-line inter-harmonic wave monitoring can be realized while high frequency resolution and accurate monitoring results can be achieved. Via the on-line inter-harmonic wave monitoring method and device disclosed in the technical solution provided in the invention, on-line harmonic wave monitoring and on-line inter-harmonic wave monitoring can be realized, harmonic waves and inter-harmonic waves are wide in measurement frequency band, and on-line monitoring of all harmonic waves and inter-harmonic waves in all frequency bands from 0 to 9 kHz can be realized. The on-line inter-harmonic wave monitoring method and device disclosed in the technical solution provided in the present invention can help effectively solve a problem that inter-harmonic wave measurement cannot be achieved currently, guidance and reference are provided for realizing full frequency band monitoring of power grid signals in a scheduling master station, and support is provided for future targeted analysis and control.

The invention relates to a dipole antenna-based active three-dimensional pulse electric field strength measuring instrument, belongs to the technical field of electric field measurement, is particularly suitable for use in the field of complex electromagnetic environments such as strong electromagnetic pulses and the like, and is used for carrying out three-dimensional measurement on the electricfields with unknown spatial directions. The dipole antenna-based active three-dimensional pulse electric field strength measuring instrument comprises a probe, a hollow metal connecting rod, a detection circuit, a power supply, a detection circuit box, an output interface and a power switch. Compared with the prior art, the dipole antenna-based active three-dimensional pulse electric field strength measuring instrument has strong anti-electromagnetic interference capability due to storage battery power supply and aluminum alloy full metal sealing, is wide in measuring frequency band range so that response exists from 0.1 MHz to 2 GHz, is compact in structure and simple to process, and can be applied to the three-dimensional electric field measurement in the field of strong electromagneticpulses.

The invention discloses a method for testing the frequency characteristic of a front plate of a fiber-optic gyroscope. The method includes the steps that a frequency control word corresponding to each testing frequency point is preset, cosine sweep check digital signals and reference digital signals are acquired by using a direct digital frequency synthetic method, wherein the reference digital signals are formed by conducting 90-degree phase shifting on the cosine sweep check digital signals, the cosine sweep check digital signals are converted into cosine sweep check analog signals and then input to the front plate of the fiber-optic gyroscope, analog digital conversion is conducted on output signals of the front plate of the fiber-optic gyroscope, and then the sample sequence of the output signals of the front plate of the fiber-optic gyroscope is acquired; two paths of correlation coefficients are acquired through correlation operations; all the testing frequency points are repeated to acquire the sequence of the two paths of correlation coefficients, and then the sequence is sent to an upper computer; parameters of the amplitude-frequency characteristic, parameters of the phase-frequency characteristic and parameters of the frequency characteristic of the front plate of the fiber-optic gyroscope are calculated and acquired. According to the method, the frequency characteristic of the front plate of the fiber-optic gyroscope can be rapidly and accurately measured, and the device utilizing the method has the advantages of being simple in structure, low in cost, high in measuring speed, large in measuring frequency range, and high in accuracy.

The invention relates to the technical field of electric power test equipment metering, and discloses a high-voltage capacitance bridge automatic frequency locking device which comprises a test power supply, the output end of the test power supply is electrically connected with a tested device and a standard capacitor, and the output end of the tested device is electrically connected with a current comparator. According to the invention, when a signal transmitted from a tested device is transmitted to a frequency detector through a current comparator, the frequency detector detects the transmitted frequency, then adjusts the unbalanced frequency through an unbalanced current regulator, and transmits the frequency adjusted by the unbalanced current regulator to a frequency selector. The frequency selector amplifies the frequency through the frequency amplifier and then transmits the amplified frequency to the balance current display device for display, and through the application of the automatic frequency locking amplification device, the situation that the safety of a whole power grid is affected due to the fact that some specific harmonic waves are damaged is avoided.