19results about "Frequency selective voltage/current level measurement" patented technology

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 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.

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.

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.

A current sensor system for accurately measuring AC currents with frequencies up to 2 kHz includes: an electrical conductor (e.g., a busbar) for conducting the AC current to create a first magnetic field; a magnetic sensor device for measuring a component or gradient of the magnetic field; and an object (e.g., a metal plate) having a conductive surface disposed near the conductor to allow eddy currents to flow in the surface, thereby creating a second magnetic field superimposed on the first magnetic field; wherein the magnetic sensor device is configured to determine the current as a signal or value proportional to the measured component or gradient. The metal plate may have openings. The current sensor system may further include a shield.

The invention belongs to the technical field of electric digital data processing, and particularly relates to a special power supply fault diagnosis method based on multi-scale feature fusion, which comprises the following steps: acquiring an output pulse sequence of a special power supply in an operation process; according to the fluctuation energy between adjacent sampling points in the output pulse sequence and the overall energy characteristics of the output pulse sequence, determining a self-adaptive scale factor for representing the signal background activity degree; for each sampling point in the output pulse sequence, determining a local attention weight corresponding to each sampling point based on the local gradient value; and in combination with the adaptive scale factor, the local attention weight and the local deviation value of each sampling point relative to the standard pulse data, determining a health score for reflecting the performance degradation degree of the special power supply, and identifying the running state of the special power supply according to the health score. The health state of the special power supply can be accurately evaluated, and the fault diagnosis sensitivity under the complex working condition is improved.

According to the IGBT hard switching loss current-sensor-free measurement method suitable for the INPC topology provided by the invention, the commutation process of the IGBT in the INPC topology is systematically analyzed from the physical mechanism of the hard switching process of a power device, and the switching characteristics of the IGBT are mainly researched. On the basis, the mapping relation between the voltage waveform characteristic and the current change and the switching loss is defined, and a corresponding hard switching loss analysis model is established. The established model only depends on device data manual parameters and actual measurement set-emitter voltage data, a current sensor or an additional test structure does not need to be introduced into a main power loop, effective evaluation of the IGBT hard switching loss in the INPC topology can be achieved, the measurement method has low requirements for test conditions, good engineering applicability is achieved, and the method is suitable for large-scale popularization and application. And the accuracy is verified through a simulation result.

The invention discloses a flexible DC converter dual fault identification method comprising the following steps: taking a flexible DC converter as a research object, carrying out period division on collected voltage data, calculating to obtain a deformation value in each period, determining the characteristic ratio of different fault types according to the deformation value, and calculating the fault type according to the characteristic ratio; and amplifying the characteristic ratio to obtain a characteristic strip of the fault type, simulating open-circuit faults of IGBT tubes of different modules, forming a fault characteristic strip library, and realizing identification of double faults of the flexible DC converter. The method gets rid of dependence on an unstable data source; the fault recognition efficiency is improved by constructing a fault feature strip library; a targeted fault handling method is provided, and a closed-loop design from identification to processing is realized.

The invention relates to the technical field of vehicles, and discloses a current ripple counting method and a vehicle, and the method comprises the steps: obtaining a current ripple waveform of a part motor under a current working condition; calculating the target offset time delay of the anti-pinch trigger reversal angle displacement in the current ripple waveform; and carrying out ripple counting on the ripple waveform in the anti-pinch execution stage in the current ripple waveform based on the target offset time delay to obtain a target ripple number. The method solves the problems that the angular displacement counteracting time delay in the reverse rotation stage of the motor after anti-pinch triggering lacks accurate calculation, so that ripple counting in the anti-pinch execution stage is inaccurate, and vehicle window positioning and anti-pinch function response are affected.

An auxiliary power circuit may measure a first time during which the voltage level of a capacitor falls from a first level to a second level by a leakage current of the capacitor, may charge the capacitor to a third level, may measure a second time during which the voltage level of the capacitor falls from the third level to a fourth level by the leakage current of the capacitor and a discharge current of a current source, may calculate a capacitance of the capacitor based on the first level, the second level, the first time, the third level, the fourth level, the second time and the discharge current of the current source, and may determine the state of the capacitor based on the calculated capacitance of the capacitor.

A current transformer includes a current sensor sensing a current of a conductor signal transmitted along a conductor and outputting a current signal based on the current and an electronic assembly connected to the current sensor and receiving the current signal from the current sensor. The electronic assembly determines an operating state of a powered device to which the conductor feeds the conductor signal based on the current signal. The electronic assembly is tuned to use the current signal of the current in a frequency range greater than or equal to 100 Hz to determine the operating state.

The invention discloses a partial discharge and temperature fusion monitoring system and monitoring method based on high-voltage power distribution equipment. The partial discharge and temperature fusion monitoring system comprises a partial discharge monitoring sensor group, a passive wireless temperature sensor group, a sampling resistor, a temperature acquisition antenna, a data acquisition unit and a data diagnosis unit. The partial discharge monitoring sensor group collects and screens high-frequency pulse current signals generated by partial discharge of the high-voltage power distribution equipment; the temperature sensor group collects temperature signals of key nodes of the equipment. The data diagnosis unit controls the data acquisition unit to send an acquisition instruction, the data acquisition unit gathers temperature data and partial discharge information and then uploads the temperature data and the partial discharge information to the data diagnosis unit, and the data diagnosis unit diagnoses the data and presents an equipment state on a local terminal or uploads the equipment state to a cloud platform. According to the invention, pulse current partial discharge and passive wireless temperature monitoring are fused, partial discharge and temperature can be monitored at the same time, faults can be warned in time, the deployment and installation cost is reduced, and the construction debugging efficiency is improved.

The application provides an IGBT hard switching loss current sensor-free measurement method suitable for an INPC topology, a commutation process of an IGBT in the INPC topology is analyzed systematically from the physical mechanism of a hard switching process of a power device, and the switching characteristics of the IGBT are mainly studied. On this basis, the mapping relationship between the voltage waveform characteristics and the current change and the switching loss is determined, and a corresponding hard switching loss analytical model is established. The model established in the application only depends on the parameters of the device data book and the measured collector-emitter voltage data, does not need to introduce a current sensor or an additional test structure in the main power loop, and can realize effective evaluation of the IGBT hard switching loss in the INPC topology. The measurement method has lower requirements for test conditions and has good engineering applicability, and the accuracy is verified by simulation results.

The invention discloses a signal processing system and method and a computer readable storage medium, and relates to the technical field of signal detection. The signal processing system comprises an IO port and a processing unit. The IO port comprises at least one input port and is used for acquiring an input variable electric signal. The processing unit is configured to continuously detect the level polarity change of the received variable electric signal, and record the moment when the level polarity of the variable electric signal is detected to change as the initial moment, and the level polarity change comprises change from low level to high level or change from high level to low level; after the initial moment, determining a power transformation time parameter of the power transformation signal according to the level duration of the power transformation signal or the moment when the level polarity change of the power transformation signal is detected again; and comparing the power transformation time parameter with a preset power transformation signal width threshold value, and when a comparison result of the power transformation time parameter and the preset power transformation signal width threshold value meets a preset effective condition, determining that the power transformation signal is an effective power transformation signal.

Systems, methods, and computer program products are disclosed for cancelling a magnetic field in a passenger region of a vehicle. Cancelling a magnetic field in a passenger region of a vehicle includes a chassis, a passenger region of the vehicle, a current carrying loop (CCL) configured to carry electricity during vehicle operation, thereby generating a magnetic field configured to radiate toward the passenger region, a sensor associated with the CCL for sensing current passing through the CCL, an electrical wire loop spatially aligned with a physical path of the CCL, and a circuit configured to: receive current sensing data from the sensor, and based on the current sensing data, determine a cancellation electrical current for providing to the electrical wire loop in order to cause a cancelling magnetic field, thereby at least reducing magnetic radiation from the CCL to the passenger region.

A radiation hardened current sensor to sense direct current (DC), low frequency alternating current (AC), and high frequency AC includes a DC current transformer (DCCT) (110) including a primary DCCT winding (111= and a secondary DCCT winding (112). A self-oscillating modulator (120) is coupled to the secondary DCCT winding of the DCCT to maintain a magnetic flux density of the DCCT at an upper limit and a lower limit of a magnetic hysteresis characteristic of the DCCT. An active filter (140) passes only the DC and the low frequency AC from the DCCT as an output. An AC current transformer (ACCT) (160) including a primary ACCT winding (161) and a secondary ACCT winding (162). The output of the active filter is coupled to the ACCT and the secondary ACCT winding provides the high frequency AC.

Disclosed is a method of measuring current for fault detection in a distribution grid (410). The method comprises: using three current transformers, wherein three current transformers are connected to one another; installing three connected current transformers in series on three phase conductors (522, 524, 526) by winding; measuring voltages of three series connected current transformers by measuring first voltage (V1) over first current transformer (102, 202, 502), measuring second voltage (V2) over first current transformer and second current transformer (104, 204, 504), measuring third voltage (V3) over first current transformer, second current transformer and third current transformer (106, 206, 506); using measured first voltage, second voltage and third voltage for determining sum current; using measured first voltage, second voltage, third voltage and calculated sum current for calculating phase currents; using determined sum current and phase currents to detect first fault transient in the distribution grid.