825results about "Electrostatic field measurements" patented technology

A method of analyzing partial discharge data collected from an electrical device includes collecting partial discharge data from a first electrical device belonging to a group of electrical devices. The group of electrical devices is at least partially defined by at least one electrical device classification. The method also includes generating a comparison of at least a portion of the partial discharge data collected from the first electrical device with at least a portion of the partial discharge data collected from at least one second electrical device. The at least one second electrical device is selected from the group of electrical devices that includes the first electrical device. The method further includes transmitting the results.

A sensor product for electric field sensing. The sensor includes a substrate, at least one electrically conductive area on the surface of the substrate, an output, and at least one conductor between the at least one electrically conductive area and the output. Also a sensor product web.

Disclosed is a UHF partial discharge and its location measuring device for high-voltage power devices. The measuring device includes a partial discharge sensor, an external noise sensor, an analogue-digital converter, a peak detector, a partial discharge signal processor, an arrival time detector, a discharge location processor, and a display unit.

The invention provides a device, a system and a method for measuring space charges by using an electro-acoustic (PEA) method. The device comprises a first electrode, a second electrode, a first thermostatic source, a second thermostatic source, a high-voltage direct current power supply, a pulse generator and a piezoelectric transducer, wherein the first electrode is used for contacting with one surface of the tested insulation material sample; the second electrode is used for contacting with the other surface of the tested insulation material sample; the first thermostatic source is used forconducting the temperature to the first electrode; the second thermostatic source is used for conducting the temperature to the second electrode; the high-voltage direct current power supply is used for transmitting the high-voltage direct current to the first electrode; the pulse generator is used for transmitting a high-voltage pulse signal to the first electrode; the piezoelectric transducer is used for detecting the acoustic signal of the tested insulation material sample, generated by the functions of the temperature gradient field, the high-voltage electric field and the high-voltage electric pulse, and is used for converting the acoustic signal into an electrical signal to output. The invention is used for measuring the distribution of the space charges in the high-voltage direct current power equipment insulation in the temperature gradient field.

A long-lived, lightweight, and quickly and precisely charged storage capacitor power supply capable of stably supplying electric power to a load. The power supply has a capacitor block consisting of capacitors connected in series, in parallel or in any combination of series and parallel. The power supply further includes a charging circuit for charging the block, a charging power supply connected with the block via the charging circuit, and a charge-limiting circuit. This charge-limiting circuit detects the voltage across the terminals of the block and limits charging of the block if the voltage reaches a given value. One embodiment of the invention further includes a charge-limiting circuit, a full charge-detecting circuit, and a residual electricity-detecting circuit connected in parallel with the block. The charge-limiting circuit senses that the voltage across the terminals of the block exceeds the given value and causes the charging current to bypass the block. The full charge-detecting circuit senses that the charge-limiting circuit is operated and determines that full charge is attained. The residual electricity-detecting circuit finds the residual electric power from the voltage across the terminals of the block. Another embodiment has a first and a second capacitor block. The voltage across the terminals of the first block is detected. The first block is charged from the second block until the detected voltage reaches a given voltage. The first block supplies electric power directly to the load.

The invention discloses a miniature electric field sensor with special-shaped electrodes, which relates to the sensor technology. A sensor sensitive structure comprises a substrate, an exciting unit, a shielding electrode, an electric field induction electrode, an anchor point and other parts. The exciting unit comprises an exciting electrode and a support beam, which are symmetrically distributed at two sides of the sensor sensitive structure; and the shielding electrode and the electric field induction electrode are arranged in staggered form, and are distributed at a middle position region of the sensor sensitive structure. The exiting unit, the shielding electrode, the electric field induction electrode, the anchor point and the like are located in the same structural layer. The miniature electric field sensor provided by the invention comprises the special-shaped electric field induction electrode and shielding electrode, thus, charge changes of the electric field induction electrode in the sensor within unit time is increased, and the sensitivity of the miniature electric field sensor is improved.

A system, in one embodiment, includes a power distribution center having an enclosure with an access door configured to move between a closed position and an open position. The power distribution center includes a non-contact sensor disposed inside the enclosure, wherein the non-contact sensor comprises a non-contact voltage sensor, or a non-contact temperature sensor, or a combination thereof. The power distribution center also includes an indicator viewable outside of the enclosure while the door is in the closed position, wherein the indicator is coupled to the non-contact sensor.

A robust, easily deployable, covert, passive intrusion detection system uses one or more E-field sensors to detect the presence of a moving individual and to provide an indication of the presence of the individual adjacent the sensor based on E-field distortion produced by the individual. Single-ended and differential E-field sensors with noise canceling and a guarding circuit provide sufficient sensitivity, with filtering from 0.5 Hz to 8.0 Hz selecting only human intruders. Either visible or invisible flashing light sources at the sensor indicate the presence of a moving individual at the sensor, thus to provide intruder location without the necessity of providing a geolocation system.

The invention relates to a weak electric field detection technology, particularly relates to an electric field detection method and device based on stark effects of Rydberg atoms, and solves the technical problems that the measurement on an electric field, particularly a weak electric field, is not accurate enough at present, and the sensitivity is not high enough. The electric field detection method based on the stark effects of the Rydberg atoms comprises the following steps: (a) oppositely arranging two beams of laser and collinearly emitting the laser into a sample tank which is internally filled with alkaline metal atom steam; (b) acquiring a signal of the second beam of the laser emitted out by the sample tank and converting the signal into a corresponding electric signal; and (c) analyzing the acquired electric signal, and if the electric field exists, observing an absorption spectrum with a stark cracking phenomenon from the signal, so as to further solve the intensity of the electric field E. According to the electric field detection method and device based on the stark effects of the Rydberg atoms, the electric field can be measured by the stark effects with an alkaline metal atom Rydberg energy level; the measurement precision is high and the electric field strength which is weakened to an mV/cm grade can be measured.

The invention discloses a microwave electric field intensity meter based on a cold Rydberg atom interferometer and a measuring method thereof. The microwave electric field intensity meter comprises: a vacuum system, which is used for cooling and trapping atom to generate a cold atom cloud for preparing a Rydberg state and generating an interference effect so as to generate a phase difference by coherent atomic states; a laser, which is used for generating coupling light and detection light and exciting the cold atom in the vacuum system from a ground state to the Rydberg state coherently; a photoelectric detector, which is used for detecting an interference fringe generated by two beams of cold atom clouds due to coherence; and a microwave source, which is used for generating a microwave electric field. According to the invention, when the microwave electric field intensity meter is applied to the evolution process of coherent beam splitting and combination, the atom cloud in the Rydberg state interacts with a to-be-measured microwave electric field, thereby generating an alternating-current stark effect; and the to-be-measured microwave electric field intensity is associated with a phase generated by the an alternating-current stark, thereby realizing precise measurement of the microwave electric field.

A voltmeter measures an unknown voltage on a target surface using multiple sampling stages or a parallel reference capacitor. A movable shutter may alternately be closed during resetting of a voltage measuring circuit and opened so as to expose a detector plate to the target surface during two sampling stages. Alternatively, the shutter may be used to modulate exposure of a detector plate to the target surface.

The invention relates to a resonance miniature electric field sensor. The sensor comprises a substrate, an exciting electrode with a comb structure, a vibration sensitive electrode with a comb structure, a shielding electrode, an electric field inductive electrode, a crossbeam and a supporting beam, wherein the exciting electrode with the comb structure is fixed on one side of the substrate by ananchor point, while the vibration sensitive electrode with the comb structure is fixed on the other side of the substrate by an anchor point; the shielding electrode and the electric field inductive electrode are fixed on the area of the substrate in the middle of the exciting electrode and the vibration sensitive electrode; the shielding electrode and the electric field inductive electrode are alternately arranged; the crossbeam is positioned in the middle of the shielding electrode; one end of the supporting beam is fixed on the substrate by the anchor point, while the other end is connectedwith the exciting electrode and the vibration sensitive electrode. The resonance miniature electric field sensor can reduce the static exciting voltage of a device, improve the sensitivity and precision of the sensor, and further improve the environment interference resistance capability of the sensor.

A method for sensing an electric field includes processing digitized electric field signals, e.g., from an electric field sensing probe. The processing may include performing a Fast Fourier Transform of the digitized electric field signals to provide an indication of the magnitude of the electric field, and may include processing the digitized electric field signals at a rate that is related to the speed at which a movable sensing probe is moving. The method may include performing unweighted and/or weighted averaging in relation to processing electric field data, setting a comparison threshold, providing a human perceivable indication, or a combination of the foregoing.

A voltage measuring apparatus measures the voltage of a measured object and includes a detection electrode capable of being disposed facing the measured object, a variable capacitance circuit that is connected between the detection electrode and a reference potential and whose electrostatic capacitance can be changed, a voltage generating circuits that generates the reference potential, and a control unit. The control unit causes the voltage generating circuit to change the reference potential while the electrostatic capacitance of the variable capacitance circuit is being changed. A power is measuring apparatus includes the voltage measuring apparatus and a current measuring apparatus that measures current flowing in the measured object, and measures power based on the current measured by the current measuring apparatus and the voltage measured by the voltage measuring apparatus.

A potential measurement apparatus for measuring a surface potential of an object of measurement detects a change in electric charge induced at a detection electrode due to electrostatic induction by changing a distance between the detection electrode and the object of measurement in accordance with a predetermined period, using a neutral distance as reference, as a signal representing a change in electric current. The potential measurement apparatus includes a first detection unit for detecting a signal representing a fundamental period of the change in electric current and a signal representing a second harmonic period, a second detection unit for detecting information representing a capacitance between the detection electrode at the neutral distance and the object of measurement and an arithmetic unit for computationally obtaining information on the surface potential of the object of measurement, with eliminating an influence of the neutral distance and the capacitance, according to an outcome of detection of the first detection unit and an outcome of detection of the second detection unit.

A fault condition monitoring apparatus for use with a fuse cutout includes a housing operable to be supported by the fuse cutout. The housing has first and second contacts operable to make electrical contact with fuse contacts on the fuse cutout when the housing is supported by the fuse cutout. A current sensor is mounted inside the housing and is connected to the first and second contacts. A signaling device is coupled to the current sensor and is operable to cause a signal to be produced when current sensed by the current sensor meets a criterion.

Methods and apparatus for analyzing electrical insulation of an electrical machine are provided. The method includes receiving a first signal that includes a plurality of partial discharge pulses from the electrical machine and a plurality of noise pulses, receiving other signals that includes information relative to at least one process parameter associated with the electrical machine, determining the plurality of partial discharge pulses from the plurality of noise pulses, identifying characteristics of the plurality of partial discharge pulses relating to the location and character of partial discharges in the electrical machine, and determining a condition of the electrical insulation using the identified characteristics and the received information relative to at least one process parameter.

A sensor for sensing an electric field includes a movable sensor probe including one or more pair, typically three pair, of electrically conductive electrodes, and may include one or more pair of selectively switchable auxiliary electrodes. The probe is movable and may be mounted on a vehicle or trailer. A processor may process electric field signals from the probe for providing a human perceivable indication of the electric field. The processor may perform a Fast Fourier Transform of the electric field signals to produce an indication of the magnitude of the electric field, and may perform unweighted and/or weighted averaging in relation to processing electric field data, setting a comparison threshold, providing a human perceivable indication, or a combination of the foregoing. A speed at which the sensor probe is moving may be utilized in processing the data.

The invention relates to a vibrating micro mechanical electric field sensor. The vibrating micro mechanical electric field sensor comprises a base and a sensitive layer and a shielding layer which are arranged on the base. The shielding layer comprises a movable structure and a fixed comb tooth structure, wherein the movable structure comprises a rectangular mass block, comb teeth and supporting beams, wherein a gap is reserved at the center of the rectangular mass block; the comb teeth are arranged around the mass block; and the supporting beams are connected with four end corners of the mass block. According to the invention, a parallel-plate capacitor can be utilized to load static electricity to tune the resonant frequency of the movable structure in the shielding layer; the vibrationdamping aiming at the movable structure in the shielding layer is tuned by the differential feedback of a vibration velocity signal; the normal pressure packaging of the vibrating micro mechanical electric field sensor is implemented; the high sensitivity can be implemented and the stability of an output signal can be improved; and the key problems of compensation on a manufacturing error, packaging, stability of the output signal and the like in an existing micro mechanical electric field sensor are solved.

The invention discloses an optical voltage transformer which is composed of a light source, a coupler, a polarizer, a phase modulator, a polarization delay optical cable, a collimating lens, a faraday rotary mirror, an electro-optical sensing unit, a photoelectric detector and a signal processing module, wherein the electro-optical sensing unit is composed of a bismuth germinate and an A and a B electrodes which are respectively installed on an upper and a lower panels of the bismuth germinate. The invention adopts the technical proposal that an electric field leads to the change of the refractive index of the sensing bismuth germinate in the electro-optical sensing unit, the phase difference of two cross-line polarized lights passing through the bismuth germinate is changed due to the Pockels effect, and the magnitude of the electric field can be indirectly measured by measuring two coherent lights.

The invention relates to a system and a method for measuring high voltage cable space charges based on an electroacoustic pulse method. A high voltage pulse source and a high voltage capacitor are connected in series and are then connected with measuring electrodes at two ends of a tested piece, a high voltage power source is further connected with the measuring electrodes at two ends of the tested piece through a current limit resistor, a piezoelectric sensor closely clings to the lower measuring electrode, the piezoelectric sensor acquires a stress wave signal and sends the processed signal to a computer to form the measuring system, the high voltage power source can be a direct current high voltage power source and further can be an alternating current high voltage power source, the alternating current high voltage power source is connected with a phase detection unit, and a phase detection circuit outputs a synchronous control signal to a pulse generation unit of the high voltage pulse source. The high voltage power source forms space charges in an insulation layer of an electric power cable through electrodes, disturbance of the charges in the insulation layer of the electric power cable is realized through the high voltage pulse source to form dynamic stress waves, the measuring system acquires a signal of a pressure sensor, and a distribution state of the space charges of the electric power cable is analyzed. Through the system and the method, measurement on the distribution state of the space charges in the insulation layer of the electric power cable under the alternating current state is realized.

The invention provides a 1000kV ultrahigh voltage alternating current non-contact-type electroscopy and an electroscope thereof, the hardware part of the electroscope consists of a signal acquisition module, a signal amplification module, a signal processing module, an analog-to-digital conversion and data processing module and an alarm module, the software part thereof is divided into five stages comprising self-check, pre-check, checkup, comparison and alarm; after the self-check is passed and time delay of 3 seconds elapses, a value, which is obtained by performing a data acquisition in 10KHz frequency on the electric field intensity of the working location, is regarded as a reference value for the electroscopy, the inventive reference value is an electric field value of the on-site working location, which effectively enhances the use range and accuracy of the electroscope; the invention implements the electroscopy in terms of field intensity curves of space electric fields and gives a reflection of the size of the electric field via the frequency velocity of acoustic, optical signals for the alarm, which effectually eradicates the interferences from adjacent charged equipment and settles the difficult problem of inferior repetitiveness and low accuracy of the electroscopy result which is resulted from the interference with the space field intensity by charged bodies of the adjacent measured equipment.

The invention discloses an apparatus for measuring the ferroelectric hysteresis of ferroelectric materials which is based on a current measurement circuit, as well as a measurement method thereof. The invention inputs a simulated output signal generated by a computer processing unit into a high voltage amplifier through a signal source and a data acquisition board, thus giving excitation voltage to a sample being tested, and then through a sampling resistance R₀, sampled current signal is input into a signal regulating module through an operational amplifier, and then the sampled current signal is transmitted back into the computer processing unit through the data acquisition board. By separating the current signal acquired from the measurement into three parts as linear polarization, non-linear polarization and electric loss, the measurement system is provided with not only the function of measuring the P-E relationship, but also the function of acquiring the relationship between the real spontaneous polarization and induced polarization of the dielectric substance being tested and the field intensity. Furthermore, by superimposing actuating signal of a small alternative electric field to a bias electric field with constant intensity and synchronously collecting the corresponding change information of the polarization intensity of the sample being tested, then the reversible permittivity can be acquired.

Disclosed in a non-contacting electric potential sensor capable of being readily reduced in its size, which includes a detecting electrode, an electrically-conductive movable shutter, and a driving unit for driving the electrically-conductive movable shutter. The detecting electrode is to be placed facing a measurement object whose electric potential is to be measured. The electrically-conductive movable shutter is disposed so as to be movably located in a spacing formed between the detecting electrode and the measurement object when the detecting electrode is placed facing the measurement object, so that an exposure degree of the detecting electrode against the measurement object can be controlled. The driving unit includes a current injecting unit for selectively injecting current into the electrically-conductive movable shutter in a direction approximately perpendicular to a moving direction of the electrically-conductive movable shutter.

A mobile radio-frequency enabled device that provides a reliable and inexpensive lightning alerting of a user. The device comprises an electromagnetic interferences detection component detecting electromagnetic interferences in radio-frequency signals received by the mobile radio-frequency enabled device for a communication link. The device further comprises a processing component to determine whether a lightning stroke can be assumed to have occurred in the vicinity of the device due to an electromagnetic interference detected by the electromagnetic interferences detection component, and to cause a notification of a user about an assumed lightning stroke via a user interface. The invention relates equally to a system which comprises such a device and a network element of a communication network, to a corresponding method and to a corresponding software program product.

An electric field signature detector for detecting and identifying objects that uses multiple electrostatic sensor nodes each having a passive sensing electrode whose free conduction electrons are displacement responsive to an externally applied or sensed electric field potential, and a transimpedance converter and amplifier exhibiting ultra-high input impedance for translating low level input displacement current from a sensing electrode into a useable output signal in response to a charge displacement signal induced on the passive sensing electrode by an external electric field. The electric field signature detector further includes an exciter for providing a reference electric field used in the retrieval and processing of an electric field signature representative of an object and class of object under investigation. The electric field signature detector having uses including military, security, anti-terrorist, and defense related.

A gas-path electrostatic monitor system of an aero-engine and a simulation test device belong to the field of gas-path stage monitor and fault diagnosis of the aero-engine. The monitor system comprises an electrostatic sensor, a signal conditioning circuit, a signal collection card and a computer. The simulation test device comprises a fuel oil burner (1), an electrostatic duster, the gas-path electrostatic monitor system, a flange (3), a first pipe (4), a rub-impact device (5), a second pipe (6), a third pipe (8), an exhaust pipe (9), an axial fan (10), a medium-pressure fan (11), a rub-impact device support platform (12) and a bracket (13). The invention can monitor the state of the engine and provide fault alarm information by monitoring the general electrostatic charge level of the gas path of the engine by the electrostatic monitor arranged at the nozzle at the tail portion of the engine. The constructed simulation test device simulates the gas-path operation state of the engine and the direct results of normal faults, thus providing a simulation test platform for early study of gas-path electrostatic monitor system of the aero-engine.

To provide an electric potential measuring device which is useful in realizing size reduction, high sensitivity, and high reliability. The electric potential measuring device includes: an oscillating device which includes torsion springs, and an oscillating body axially supported by the springs to oscillate; and signal detecting unit which is located on a surface of the oscillating body. A capacitance between the detection electrode and a surface of an electric potential measuring object is varied by varying a distance therebetween by the oscillating device, whereby an output signal appearing on the detection electrode is detected.

A shielding member is provided as an electrostatic protection device in extension lines that extend from a sensing area to switching devices via extension areas correspondingly. As a result, even if a body to be detected such as a finger contacts the extension area, it is possible to reduce the amount of the change of an electrostatic capacitance with respect to the movement of the body to be detected. Therefore, it is possible to reduce influences exerted on data to be detected, and an electrostatic detection apparatus having improved coordinate detection accuracy can be provided.

The invention discloses a comprehensive underground test method for deformation and damage of terranes of mining top plate and mining bottom plate of a coal bed, comprising the following steps of: (1) constructing a comprehensive test system; (2) utilizing a network parallel electrical method to synchronously collect test electrode supply current and potential signal in boreholes of the top plate and the bottom plate, thus obtaining the electric field distribution situation between the top plate and the bottom plate of the working face in a control area; (3) respectively extracting the electric field parameter distribution situation of rock masses, the seismic velocity distribution situation and the displacement variation of terranes at different places in the borehole in the control area according to the collected data characteristics of various geophysical fields; (4) dynamically obtaining the parameter change of the geophysical fields in a detected area at different time along with the advancing state of the working face; and (5) completing the installation and sealing of facilities in the tested borehole before the stoping of the coal face. The method precisely masters the damage situation of the rock masses, thus not only delimitating the deformation and damage distribution situation of rock masses in the control area, but also precisely determining the water-guiding fissure zone height of the covered rock masses of the top plate and the damage depth value of the bottom plate.