17 results about "Gmr sensor" patented technology

The invention provides an intelligent eddy current nondestructive testing method and system based on a flexible GMR sensor array, and relates to the technical field of nondestructive testing. According to the invention, a GMR sensor array and a micro excitation coil array are integrated on a flexible substrate, and synchronous acquisition under multi-frequency and multi-phase excitation is realized by establishing a probe-workpiece unified space coordinate system and a time synchronization reference; performing temperature drift compensation, attitude correction and gap normalization processing on the original response tensor to generate a corrected response tensor; the intelligent inversion model based on the prior constraint of the electromagnetic field jointly identifies the conductivity, the thickness and the crack parameters, and outputs a defect parameter map and a confidence map; and a detection report containing the position, the size, the depth and the confidence coefficient is generated through spatial clustering and connectivity analysis, so that high-sensitivity and high-reliability nondestructive detection under a complex curved surface structure is realized.

A guided mode resonance (GMR) sensor that can be used to simultaneously detect an array of analytes. It provides a diagnostic system that can rapidly detect an array of biomarker proteins in patient samples (such as blood, serum or plasma for example) which can be used as an accurate means to conduct a differential analysis of proteins that allows the discrimination of early and late stages of disease, such as metastatic versus primary ovarian serous carcinomas. The GMR sensor can be provided in a compact size such that it can be portable.

The present invention discloses a primary current measurement system for an electromagnetic voltage transformer based on a GMR sensor, which relates to the technical field of power system monitoring. It includes a composite magnetic circuit module, which realizes magnetic flux separation through a conical ferrite magnetic ring, a main magnetic circuit and an auxiliary magnetic circuit, conducts the power frequency magnetic flux to the iron core, and conducts the high-frequency magnetic flux to the GMR sensor array. The GMR sensor array adopts an orthogonal dual sensor combined with a ring distribution and is equipped with a differential output channel to effectively eliminate position deviation. The signal processing module integrates a preamplifier, an analog-to-digital converter, a dual-frequency bandpass filter and an embedded processor, executes an adaptive Kalman filter algorithm, and improves signal processing accuracy. The system also has insulation shielding, reliability assurance and temperature compensation modules, which respectively provide electromagnetic shielding, hardware monitoring, dual power supply redundancy and ambient temperature compensation functions to ensure the safe and stable operation of the measurement system. The present invention is suitable for current measurement in power systems and has significant technical advantages and practical value.

The invention belongs to the technical field of overvoltage protection of a power system, and particularly relates to a ferromagnetic resonance flexible device based on a power electronic converter, a power electronic converter module adopts a full-bridge uncontrolled rectification and double-switch BUCK chopper circuit topology, and dynamic simulation equivalent damping resistance is adjusted through the duty ratio of an MOSFET (Metal-Oxide-Semiconductor Field Effect Transistor) switch; the signal acquisition module is integrated with a GMR sensor, a T-type thermocouple and a voltage detection unit; the control module carries out ferromagnetic resonance characteristic identification based on an FFT algorithm, combines critical conduction mode control and a model reference adaptive PI control algorithm, dynamically generates a PWM signal to drive the converter to work, and realizes rapid adaptive dissipation of resonance energy. Through multi-parameter fusion detection and a composite control strategy, the response speed and the adjustment precision of ferromagnetic resonance suppression are effectively improved, the functions of state self-diagnosis, parameter visual configuration and remote data interaction are achieved, and the operation reliability of a power system is remarkably improved.

The present invention relates to a nano- or microparticle comprising a matrix made of or comprising at least one polyvinyl alcohol (PVA), and ferrite dispersed therein, as well as a method for obtaining it. The present invention also relates to the use of these nano- or microparticles for the preparation and implementation of devices capable of being detected by giant magnetoresistance sensors (GMR sensors) as biological diagnostic tools.

A signal processing system used for GMR-based detection of a target analyte in a sample under test, comprising: a measurement circuit configuration unit configured to build a GMR sensor measurement circuit by routing in at least one GMR sensor, and to build a reference resistor measurement circuit by routing in at least one reference resistor; a magnetic field excitation unit configured to apply an AC magnetic field of frequency ω2 to the at least one GMR sensor; a carrier signal applying unit configured to apply a carrier signal of frequency ω1 to the GMR sensor measurement circuit, and apply carrier signals of frequency ω1, ω1+, ω2, and ω1−ω2 to the reference resistor measurement circuit; a measurement signal pick-up unit coupled to the measurement circuits, configured to collect reference resistor measurement signals from the reference resistor measurement circuit and GMR sensor measurement signals from the GMR sensor measurement circuit; and a phase sensitive solution unit coupled to the measurement signal pick-up unit, configured to analytically solve for resistance change of the at least one GMR sensor based on both the reference resistor measurement signals from the reference resistor measurement circuit and the GMR sensor measurement signals from the GMR sensor measurement circuit.

The invention discloses a refractive index detection device and method based on a width-gradually-changed guided mode resonance grating, and belongs to the technical field of optical sensing. Light emitted by a light source enters a guided mode resonance sensing chip after passing through an optical isolator, a polarization controller and a collimation beam expander, the guided mode resonance sensing chip is of a transmission type structure, and the width of the guided mode resonance grating is gradually changed; a strip-shaped nano structure with gradually-changed strip width is arranged at the top of the substrate; and an image detector is arranged below the guided-mode resonance sensing chip, receives a transmission light signal passing through the guided-mode resonance sensing chip, generates a transmission light image, transmits the transmission light image to a signal processing unit for analysis, and inverts the refractive index of the medium to be measured according to the mapping relation between the strip width and the refractive index. Resonance wavelength is mapped into image position information through space structure design, a traditional light splitting device is not needed for refractive index inversion, high-precision, imaging and real-time refractive index detection is achieved, and the problems that a traditional guided-mode resonance sensor needs complex optical elements and is large in size and high in cost are solved.

Methods of, inter alia, detecting the presence of one or more analytes in one or more query samples include providing one or more sensor that each include biomolecules disposed on a functionalized surface of one or more giant magnetoresistance (GMR) sensors. Modes of operation remove or add magnetic beads from the vicinity of sensor surfaces by interactions with the biomolecules. The methods feature, inter alia, detecting the presence of one or more analytes in one or more query samples by measuring magnetoresistance change of the one or more GMR sensors based on determining magnetoresistance before and after passing magnetic particles over the one or more sensors.

An elevator car positioning system includes a plurality of magnetic field producers, each of the plurality of magnetic field producers located in a position corresponding to an entry / exit point of an elevator. A giant magnetoresistance (GMR) sensor is disposed on an elevator car of the elevator to detect individual ones of the plurality of magnetic field producers when within a given detection range of the GMR sensor and generate detection signals indicative thereof. A controller is in communication with the GMR sensor and is configured to receive the detection signals from the GMR sensor, determine a position of the elevator car relative to the entry / exit point based on the received detection signals, and generate control signals to position the elevator car.

An embodiment of the present invention discloses a detection method, device and system for asymmetric damage of a casing; the detection device includes: a plurality of detection probes; wherein each of the detection probes includes a magnetic core, a transmitting coil wound around the outer periphery of the magnetic core, and a plurality of giant magnetoresistive GMR sensors wound around the longitudinal center position of the transmitting coil and uniformly distributed in a circular array; wherein the plurality of detection probes are coaxially distributed in sequence along a set detection depth, and each of the detection probes rotates along a common rotation axis in the same direction at a set angle, so that all the GMR sensors form a circular array and are uniformly distributed in the 360° direction around the wellbore, so as to determine the azimuth and three-dimensional shape of the asymmetric damage of the casing according to the received response of the synthesized circular array.

Rotation detection device (1) comprising: a detected element (2) mounted on a rotating element (11) and having multiple magnetic poles arranged circumferentially around an axis of rotation (O) of the rotating element (11); and a sensor section (3) mounted on a stationary element (9) that does not rotate with the rotation of the rotating element (11) and is arranged so that it faces the detected element (2); wherein a retaining hole (90) for holding the sensor section (3), which penetrates the stationary element (9) in a radial direction to the axis of rotation (O), is formed in the stationary element (12), wherein the sensor section (3) is inserted into the retaining hole (90) in the radial direction to the axis of rotation (O), wherein the sensor section (3) comprises: several magnetic sensors (30), each comprising a plate-shaped detection section (300) comprising a magnetism detection element for detecting a magnetic field from the detected element (2), a signal processing circuit for processing a signal output by the magnetism detection element, and a cover that jointly covers the magnetism detection element and the signal processing circuit, wherein the sensor section (3) comprises a housing section (31) that jointly covers the multiple magnetic sensors (30), wherein the detection sections (300) are stacked in a direction parallel to the axis of rotation (O) in which the sensor section (3) and the detected element (2) face each other, and wherein the sensor section (3) comprises two magnetic sensors (30), wherein the magnetic sensor (30) located furthest from the detected element (2) has a higher sensitivity than the magnetic sensor (30) located closest to the detected element (2), and wherein the magnetic sensor (30) located on a side closer to the detected element (2) comprises a Hall IC and the magnetic sensor (30) located on the side opposite the detected element (2) comprises a GMR sensor, an AMR sensor or a TMR sensor.

The application discloses a kind of railway vehicle bogie bolt fast inspection device and quantitative evaluation method, belong to railway vehicle nondestructive testing technical field.The device includes array spontaneous leakage magnetic probe, spatial positioning mechanism and signal processing unit.Array spontaneous leakage magnetic probe uses high sensitivity GMR sensor array, picks up high intensity bolt self remanence generated spontaneous leakage magnetic signal, without additional magnetizing device;Space positioning mechanism synchronously records probe position coordinate;Signal processing unit extracts signal peak-peak value, waveform width and other characteristics, combined with CNN-LSTM multi-task deep learning model, output bolt's pre-tightening force retention rate, damage classification result and stress history index.The application does not need external magnetic field, operation is safe and convenient, single bogie detection time is shortened to within 5 minutes, realizes the non-contact, fast, quantitative evaluation of railway vehicle bolt in-service state, provides technical support for railway vehicle digital operation and maintenance.

This application relates to a method for enhancing giant magnetoresistive (GMR) sensor signals based on multi-channel fusion. The method includes: calibrating the complex domain frequency response of each GMR channel to obtain discrete complex sampled values ​​of differential-mode sensitivity and common-mode response transfer function at a preset frequency set; acquiring multiple original digital signal streams, and obtaining complex spectral data for each channel and frequency slot through framing and short-time frequency domain transformation; obtaining estimated values ​​of the common-mode transfer function of each channel relative to a reference channel through frame-by-frame adaptive blind identification; obtaining a compensated multi-channel time-domain signal sequence through frequency domain consistency compensation, inverse transformation, and time-domain reconstruction; and finally, outputting the enhanced GMR sensor signal through statistical optimal weighted fusion and sparse domain enhancement. This method can accurately suppress common-mode interference, align the frequency domain characteristics of multiple channels, and improve the signal-to-noise ratio and detection sensitivity of the GMR sensor signal.

The application belongs to the technical field of power system overvoltage protection, and particularly relates to a ferromagnetic resonance flexible device based on a power electronic converter, wherein a full-bridge uncontrolled rectification and a double-switch BUCK chopper circuit topology are adopted in the power electronic converter module, and a dynamic equivalent damping resistor is simulated through duty cycle adjustment of a MOSFET switch; a signal acquisition module integrates a GMR sensor, a T-shaped thermocouple and a voltage detection unit; a control module performs ferromagnetic resonance feature identification based on an FFT algorithm, combines critical conduction mode control and a model reference self-adaptive PI control algorithm, dynamically generates a PWM signal to drive the converter to work, and realizes rapid self-adaptive dissipation of resonance energy. Through multi-parameter fusion detection and a composite control strategy, the application effectively improves the response speed and the regulation accuracy of ferromagnetic resonance suppression, has state self-diagnosis, parameter visual configuration and remote data interaction functions, and significantly improves the operation reliability of a power system.

The utility model discloses a current sampling device based on GMR sensors. The current sampling device comprises an injection molding part, a U-phase silicon steel sheet shielding case, a V-phase silicon steel sheet shielding case, a W-phase silicon steel sheet shielding case, a U-phase copper bar, a V-phase copper bar, a W-phase copper bar, a U-phase GMR sensor, a V-phase GMR sensor, a W-phase GMR sensor and a PCB. The lower surface, the left side surface and the right side surface of the U / V / W phase copper bar are respectively kept at a distance of more than 1mm from the U / V / W phase silicon steel sheet shielding case, the upper surface of the U / V / W phase copper bar is respectively kept at a distance of less than 10mm from the lower surface of the U / V / W phase GMR sensor, the U / V / W phase GMR sensor is welded on the bottom layer of the PCB, the U / V / W phase GMR sensor is respectively positioned at the central position opposite to the U / V / W phase silicon steel sheet shielding case, and the U / V / W phase silicon steel sheet shielding case vertically penetrates through the PCB. The U / V / W-phase GMR sensors convert magnetic fields generated by U / V / W-phase copper bar currents into voltage signals respectively so as to achieve the purpose of current sampling, and the U / V / W-phase silicon steel sheet shielding cover has the effects of gathering magnetism and reducing crosstalk.

The invention discloses a fan-shaped magnetic flux large current measuring system and method, and the system comprises a closed circular ring which is formed by splicing a plurality of arc-shaped iron-based amorphous magnetic cores, and a certain air gap is formed between each magnetic core and an adjacent magnetic core; gMR sensors are arranged in air gaps of the inner ring of the circular ring, and the two ends of each GMR sensor are connected with the two adjacent arc-shaped iron-based amorphous magnetic cores respectively. Current detection is performed through the four-air-gap fan-shaped magnetic field magnetic ring structure formed by the four arc-shaped iron-based amorphous magnetic cores, so that the magnetic field gradient at the air gaps is minimum, an optimal site of the sensor is naturally formed, positioning dependence is eliminated, finite element simulation is omitted, magnetic field measurement is performed through the structure, and the deviation position of a current wire is calculated. The current measuring device has the advantages of being simple in design and production, high in measuring result consistency, large in current measuring range and simple in measurement, installation and implementation.

A tactile sensor device is disclosed. In one embodiment, giant magnetoresistance (GMR) sensors form multiple Wheatstone bridges on a base substrate to detect a magnetic field generated by a nearby ferromagnet. This ferromagnet is embedded within an elastomer matrix that deforms upon contact with an external object, displacing the ferromagnet. Consequently, the GMR sensors detect changes in the magnetic field resulting from the ferromagnet's displacement, thereby quantifying the contact.