115results about "Frequency selective voltage/current level measurement" patented technology

The invention relates to the technical field of power equipment state monitoring, in particular to a transformer iron core alternating current and direct current mixed current on-line monitoring method and system based on a magnetoelectric coupling sensor, and the method comprises the steps: monitoring the change of magnetic flux generated by the vibration of an iron core in a transformer in real time through a magnetoelectric coupling sensor array; the magnetic flux change is converted into an original electric signal, the original electric signal is processed, an alternating current signal component and a direct current signal component in the mixed current are extracted, and historical operation data and real-time environment parameters of the alternating current signal component and the direct current signal component are input into a deep recurrent neural network to be trained; and the deep recurrent neural network outputs the enhanced stray current and the direct current signal after the environmental influence is eliminated after iterative training. According to the invention, high-precision prediction of the temperature of the iron core is realized by using a method of combining a deep recurrent neural network and adaptive decomposition; and the neural network is trained by using the dynamic data, so that the dynamic processing capability of the network is enhanced and the operation reliability of the transformer can be effectively improved.

The invention relates to the technical field of electric energy identification, in particular to an energy consumption identification system based on a power transformation aliasing scene, which comprises a disturbance boundary extraction module, a boundary stability judgment module, an aliasing state identification module, a periodic power calculation module and an energy consumption attribution judgment module. According to the method, a voltage sag record with a phase offset characteristic is formed through continuous tracking of the periodic voltage fluctuation starting and ending point indexes, a stable fluctuation judgment mechanism is constructed in combination with offset statistics, and accurate identification of aliasing sections is realized by means of disturbance amplitude and frequency extraction. A power sequence is constructed on the basis of voltage and current synchronous sampling values, period integration is completed, a high-precision calculation result of energy consumption is formed, fine division of cross interference period energy consumption under the condition of no physical isolation is achieved, dependence of external metering equipment is avoided, independent quantization of overlapping load energy consumption is achieved, and the calculation efficiency is improved. And a feasible means is provided for energy efficiency evaluation in a non-intrusive load identification and high-coupling scene.

A shunt-based current sensor executes redundancy detection of a load current flowing through a load by using a shunt resistor. The shunt-based current sensor includes a reference resistor, a current excitation circuit, at least two voltage measurement circuits and a signal processing circuit. The reference resistor is connected to the shunt resistor in series. The current excitation circuit generates an AC excitation current and supply the AC excitation current to the shunt resistor and the reference resistor. At least two voltage measurement circuits measure a voltage across the shunt resistor. A signal processing circuit executes signal processing based on respective measurement voltages of the at least two voltage measurement circuits, and is operated in the load current redundancy detection mode or a shunt resistance measurement mode.

An electronic device may include an antenna, a receiver, and a transmission line path that couples the antenna to the receiver. A peak detector may receive a radio-frequency signal from the transmission line path and may output a DC voltage indicative of a peak voltage level of the signal. The peak detector may include a pair of square law transistors having source-drain terminals coupled to an output of the peak detector. The peak detector may include a differential pair of transistors coupled between a power supply voltage and the output. The peak detector may include diode-connected transistors coupled between the source-drain terminals and gate terminals of the square law transistors. The diode-connected transistors may cause noise current to flow along feedback loop paths from the source-drain terminals onto the gate terminals of the square law transistors. This may remove noise from the output of the peak detector.

To provide a shunt type current sensor designed to sense shunt resistance values at low cost in a current sensor that performs redundancy detection.SOLUTION: A signal processing circuit 14 operates in one of a load current redundancy detection mode and a shunt resistance measurement mode. In the load current redundancy detection mode, the voltage applied to a shunt resistor 12 is measured using voltage measurement circuits 13, 13a while an AC exciting current IE is not flowing from a current exciting circuit 52 to a reference resistor 12a and a shunt resistor 12, and a load current IL is flowing from a load 80 to the shunt resistor 12, and the redundancy of the load current IL flowing to the load 80 is detected. In the shunt resistance measurement mode, a resistance value RS of the shunt resistor 12 is detected on the basis of the voltage of the reference resistor 12a and the voltage of the shunt resistor 12 measured by the voltage measurement circuits 13, 13a, respectively when the AC exciting current IL is flowed from the current exciting circuit 52 to the reference resistor 12a and the shunt resistor 12.SELECTED DRAWING: Figure 1

This application relates to the field of lightning rod lightning protection monitoring technology, specifically to a corona field delayed lightning rod and its operation monitoring method. The method includes: collecting corona current and electric field intensity at each moment within each monitoring cycle during the operation of the lightning rod; calculating the first evaluation value and electric field anomaly degree for each time period in each monitoring cycle to obtain the first interference degree for each time period in each monitoring cycle; determining the second evaluation value and cycle anomaly degree for each time period in each monitoring cycle to obtain the second interference degree for each time period in each monitoring cycle; determining the interference coefficient for each monitoring cycle; and evaluating the data distortion status monitored during the operation of the lightning rod. This application, by evaluating the monitored data distortion status, reduces the possibility of misjudgment or omission of lightning strike risk by the lightning rod, and improves the accuracy of assessing the strength of corona discharge generated by the corona field delayed lightning rod under the action of the electric field and the activity of thunderclouds.

A process for current measurement includes a recombination of a low frequency current signal ILF coming from a low frequency current sensor and at least one high-frequency current signal IHF+offset coming from a high-frequency sensor on a single current conductor. The process includes the steps of amplification, filtering, and summing of signals suited to eliminating a direct offset created during amplification of the HF signals.

The invention relates to a method for measuring an electric current. In the method, a measurement signal dependent on the current is repeatedly captured and, for each measurement signal, the measurement signal is filtered by means of a bandpass filter (5) in order to form a filtered measurement signal. Furthermore, for each measurement signal the first derivative of the measurement signal with respect to time and the first derivative of a power density value with respect to time are determined, the power density value being formed from a spectral power density of the measurement signal. A weighted average value of the measurement signal and of the filtered measurement signal is formed as a measure of the current intensity of the current, wherein the weight of the measurement signal increases monotonically with rising first derivative of the measurement signal with respect to time and with rising first derivative of the power density value with respect to time.

Embodiments disclosed herein include a sensor. In one embodiment, a sensor comprises: a plate in which a hole is formed through the plate; a current loop which passes through the plate in a bent manner around the hole; and a voltage loop surrounding the bore and within an inner periphery of the current loop, where the voltage loop includes: an inner loop; an insulating ring surrounding the inner ring; and an outer ring surrounding the insulating ring.

An electronic device may include an antenna, a receiver, and a transmission line path that couples the antenna to the receiver. A peak detector may receive a radio-frequency signal from the transmission line path and may output a DC voltage indicative of a peak voltage level of the signal. The peak detector may include a pair of square law transistors having source-drain terminals coupled to an output of the peak detector. The peak detector may include a differential pair of transistors coupled between a power supply voltage and the output. The peak detector may include diode-connected transistors coupled between the source-drain terminals and gate terminals of the square law transistors. The diode-connected transistors may cause noise current to flow along feedback loop paths from the source-drain terminals onto the gate terminals of the square law transistors. This may remove noise from the output of the peak detector.

Embodiments disclosed herein include a sensor. In an embodiment, the sensor comprises a board, wherein an aperture is formed through the board, a current loop winding through the board around the aperture, and a voltage ring around the aperture and within an inner perimeter of the current loop, wherein the voltage ring comprises an interior ring, an insulator ring around the interior ring, and an exterior ring around the insulator ring.

A sensor assembly includes a sensor generating a sensor signal, an output unit and a condition unit receiving the sensor signal output from the sensor, and a test line connected to the sensor and the condition unit. The output unit outputs a signal output representative of a state detected by the sensor. The condition unit outputs a condition output representative of a condition of the sensor. The test line is bidirectional and outputs the condition output.

This application discloses a measurement apparatus that does not use a femtosecond laser light source and a delay stage. The measurement apparatus mixes a first laser light from a first CW laser light source and a second laser light from a second CW laser light source to generate an interference light having a beat in a range from GHz to THz and demultiplexes the interference light into a pump light and a probe light. A generating photoconductive antenna is irradiated with the pump light, and a detecting photoconductive antenna is irradiated with the probe light. A current value of an electromagnetic wave propagating through a waveguide connecting the generating photoconductive antenna and the detecting photoconductive antenna is measured using a current system connected to the detecting photoconductive antenna.

A tracking current is separated easily. A current measurement apparatus 10 according to the present disclosure is configured to measure a tracking current. The current measurement apparatus 10 includes a magnetic core 11 that can be disposed so as to enclose wiring 100 to be measured, and first and second coils L1 and L2 wound on the magnetic core 11. The number of turns of the second coil L2 is smaller than that of the first coil L1. The second coil L2 is configured to be able to detect the tracking current flowing through the wiring 100.

A magnetic field sensor for sensing a current flowing in a first direction divided in at least two conductor portions separated in a second direction, the sensor comprising at least two sensing elements for sensing the magnetic field at two positions in a region between the two conductor portions, wherein the at least two sensing elements are adapted to sense the field at the respective position with the highest sensitivity in a direction being between 20 degrees and 160 degrees from a third direction being perpendicular to both the first and second direction, wherein the two positions are separated by a predetermined distance in the third direction

Techniques are provided for current collector diagnosis. In one embodiment, the techniques involve determining that a current is flowing through a current collector of the battery cell, generating a mechanical excitation to the current collector, determining an amplitude of the voltage across the battery cell based on the mechanical excitation, and determining a presence of a tear or a separation of a foil of the current collector based on the amplitude of the voltage across the battery cell.

A test and measurement probe system, including an input to receive an input signal, the input signal including a low frequency (LF) and / or direct current (DC) component and an alternating current (AC) component, an extractor circuit, such as an AC coupling circuit or a LF and / or DC rejection circuit, configured to receive the input signal and to separate the AC component and the LF and / or DC component from the input signal, a first output to output the alternating current component to the test and measurement instrument, and a second output to output the direct current component to the test and measurement instrument. In some embodiments, the LF and / or DC component is digitized prior to being output by the second output.

A method and system for use in reducing magnetic fields generated by an electrical system includes determining one or more current-carrying loops in electrical wiring of an electrical system, providing a parallel wire loop to at least one of the one or more current-carrying loops generally overlapping a physical path of the at least one current-carrying loop, connecting the parallel wire loops to a power system having at least one sensor, operating the at least one current sensor to provide sensed data indicative of a current passing through the at least one current-carrying loop, and operating the power system based on the sensed data to transmit a current through the parallel wire loop in a direction opposite to the current passing through the at least one current-carrying loop, thereby eliminating a magnetic field generated by the current passing through the current-carrying loop.

An impedance measurement device of the present disclosure includes: an electrochemical energy device; an amplifier connected to each connection terminal of the electrochemical energy device and configured to amplify a signal introduced into a wiring; and a main board configured to receive the signal from the amplifier and measure an impedance. Accordingly, the present invention has advantages in that high resistance to electromagnetic interference may be achieved by disposing a preamplifier close to a terminal of an electrochemical energy device to amplify only the signal without amplifying a noise introduced into a wiring.

Method for measuring an electric current with a measuring device (1), wherein - a current-dependent measurement signal is repeatedly acquired using a current transformer (3), - for each measurement signal a filtered measurement signal is formed by filtering the measurement signal with a bandpass filter (5), - with an evaluation unit (7) for each measurement signal, the first derivative of the measurement signal with respect to time and the first derivative of a power density value of the measurement signal with respect to time are determined, wherein the power density value is formed from a spectral power density of the measurement signal, and - as a measure of the current strength, a weighted average of the measurement signal and the filtered measurement signal is formed, whereby the weight of the measurement signal increases monotonically with increasing first derivative of the measurement signal with respect to time and with increasing first derivative of the power density value with respect to time.

System for diagnosing a battery cell (204) of a vehicle (100), comprising: a processor (302) and a working memory (304) or data storage (308) comprising an algorithm or computer instructions which, when executed by the processor (302), perform an operation comprising: Determine that a current flows through a current collector (206, 214) of the accumulator cell (204), Generating a mechanical excitation of the current collector (206, 214), Determining the amplitude of a voltage across the accumulator cell (204) based on mechanical excitation, and Determining the presence of a crack or separation of a foil of the current collector (206, 214) on the basis of the amplitude of the voltage across the accumulator cell (204).

The present invention relates to the field of power systems and automation, and discloses a method and system for identifying discharge hazards of transmission lines. The method comprises: acquiring and processing measured data of discharge hazards of the transmission lines, high-frequency discharge waveform data, and acquiring and discharge event data; creating a hazard identification requirement table and initializing same, and updating all elements in the table in the time sequence; looking up, for each newly acquired waveform segment, table to determine the operation and maintenance requirement, and performing comprehensive early warning on the hazard state of the lines.

Techniques for current collector diagnostics are provided. In one embodiment, the techniques include determining that a current is flowing through a current collector of the battery cell, generating a mechanical excitation to the current collector, determining an amplitude of the voltage across the battery cell based on the mechanical excitation, and determining the presence of a crack or separation of a foil of the current collector based on the amplitude of the voltage across the battery cell.

The invention discloses a motor phase current sampling device and method, a chip and a motor controller, the device comprises a reference voltage providing unit, a sampling unit and a control unit, the reference voltage providing unit is connected with the reference ground end of the sampling unit, and the control unit is connected with the sampling unit; the reference voltage providing unit is used for outputting partial voltage of neutral point voltage of the motor; the sampling unit is used for sampling a motor phase voltage corresponding to each phase of bridge arm in the multi-phase bridge arm based on voltage division; the control unit is used for controlling the reference voltage providing unit to output the partial voltage of the voltage of the neutral point of the corresponding motor in the target sampling period of each phase of bridge arm in a pulse modulation period, and controlling the sampling unit to sample the corresponding motor phase voltage based on the partial voltage to obtain a plurality of motor phase voltage sampling values. Determining a motor phase current according to the plurality of motor phase voltage sampling values; wherein the target sampling time period is the time period from the dead time corresponding to each phase of bridge arm to the time period before follow current is completed. The phase current sampling cost of the device is low.

The invention relates to a method for measuring a current digitally recombining a low-frequency current signal IBF from a low-frequency current sensor and at least one high-frequency current signal IHF+offset from a high-frequency current sensor on the same current conductor, the method comprising the steps of amplifying, filtering and summing the signals, said steps being suitable for eliminating a DC offset created in the amplification of the HF signals.

According to the cable fault positioning device and method in the operation state of the cross interconnection system, the cross interconnection system does not need to be reconnected, positioning is carried out by capturing the time difference of fault breakdown current through the head end sensor and the tail end sensor, the problems that a grounding system needs to be disassembled and complex waveform recognition experience is relied in a traditional method are solved, and the fault positioning accuracy is improved. The efficiency and accuracy of long-distance cable fault positioning and the convenience of field operation are improved; according to the cable fault positioning device, a tested fault cable grounding system is in a cross interconnection operation state, and the cable fault positioning device comprises an impulse voltage unit, a head end sampling unit, a tail end sampling unit and a data processing system. The impulse voltage unit is used for generating impulse voltage enabling breakdown discharge of a cable fault point; and the head end sampling unit filters out high-frequency impact current generated when the impact voltage unit discharges, provides a follow current channel for pulse current generated by breakdown of a cable fault point, collects the pulse current generated by breakdown of the cable fault point, records the pulse current and uploads the pulse current to the data processing system.

The present invention relates to the technical field of power equipment condition monitoring, and particularly relates to an on-line monitoring method and system for AC-DC hybrid current in a transformer core based on a magnetoelectric coupling sensor. This method uses a magnetoelectric coupling sensor array to real-time monitor the change in magnetic flux generated by the vibration of the transformer core inside, converts the change in magnetic flux into an original electrical signal, processes the original electrical signal, extracts the AC signal component and DC signal component in the hybrid current, and inputs them along with historical operation data and real-time environmental parameters into a deep recurrent neural network to be trained. After iterative training, the deep recurrent neural network outputs the enhanced stray current and the DC current signal after eliminating the environmental impact. The present invention uses a method combining a deep recurrent neural network and adaptive decomposition to achieve high-precision prediction of the core temperature; and uses dynamic data to train the neural network, thereby enhancing the dynamic processing ability of the network, and can effectively improve the operation reliability of the transformer.

A system for locating defects on a single-wire earth-return (SWER) network can include a network, a plurality of data collection units, and a server communicably coupled to the plurality of data collection units via the network. Each data collection unit can be positioned at a distribution transformer of the SWER network and configured to measure broadband signals originating from a defect along the SWER network; convert the broadband signals to a digital signal; extract parameters from the digital signal; and transmit the extracted parameters over the network. The server can be configured to receive the extracted parameters from each of the plurality of data collection units; and determine a location of the defect based on the extracted parameters.

The present invention discloses a method, device and storage medium for determining the residual magnetic flux of a transformer. The method comprises: obtaining a current signal generated by at least one transformer in a power grid at at least one node at the moment of power failure; determining a target current peak value from the current peak value corresponding to the current signal, wherein the target current peak value is used to represent each current peak value between adjacent cycles of the node at the moment of power failure; performing linear fitting on the target current peak value based on a fitting template to obtain the fitting goodness of the original current signal and the fitting curve of the attenuation characteristic corresponding to the current signal; in response to the fitting goodness exceeding the fitting goodness threshold, determining the residual magnetic flux of the transformer under the original current signal based on a preset database corresponding to the type of the transformer, wherein the preset database is used to store the mapping relationship between the original current signal and the residual magnetic flux. The present invention solves the technical problem of low efficiency in estimating the residual magnetic flux of the transformer.

A power detection circuit for detecting a current total input power of a resonant circuit. The power detection circuit comprises a detection circuit and an estimation circuit. The detection circuit receives a current signal and obtains a resonant tank fundamental power from the current signal to generate a fundamental power value. The current signal represents a resonant tank current generated by the resonant circuit. The estimation circuit receives the fundamental power value and estimates the current total input power from the fundamental power value to generate an estimated power value. The disclosure also relates to a control circuit.