35results about How to "Improve current measurement accuracy" patented technology

The invention discloses an all-fiber current sensor consists of a 3x3 polarization-maintaining fiber coupler. One embodiment of the invention, a straight-through type interferometric all-fiber current sensor, comprises a light source, a 3x3 polarization-maintaining fiber coupler, fiber polarizers, a 1/4 fiber wave sheet and a transduction fiber ring. The light source is connected with one end of the 3x3 polarization-maintaining fiber coupler; the two ports of the 3x3 polarization-maintaining fiber coupler are respectively connected with two fiber polarizers; and the other ends of the two fiber polarizers are respectively connected with the transduction fiber ring by the 1/4 fiber wave sheet; one port of the 3x3 polarization-maintaining fiber coupler is vacant; and the rest two ports of the 3x3 polarization-maintaining fiber coupler are respectively connected with a signal processor by two photoelectric detectors. In addition, another embodiment of the invention, a reflection type interferometric all-fiber current sensor, also uses the 3x3 polarization-maintaining fiber coupler. The all-fiber current sensor avoids phase differences made artificially and makes the current transduction system woke more stably.

A current sensor includes a first conductor and a second conductor arranged so as to form current paths parallel to each other; a circuit board arranged such that a surface thereof is perpendicular to the current paths; and a first magnetoelectric transducer and a second magnetoelectric transducer arranged on the surface of the circuit board such that the first conductor is interposed therebetween. The first conductor, the second conductor, the first magnetoelectric transducer, and the second magnetoelectric transducer are located on a same plane.

The invention relates to a high-accuracy electronic compensated current transformer, and belongs to the field of current measuring. The compensated current transformer is composed of an iron core, a winding and an auxiliary circuit used for compensating a magnetizing current. The iron core is a nested structure composed of a detecting iron core and a shielding iron core, the detecting iron core detects the zero magnetic flux state of the iron core through the winding wound on the detecting iron core and then controls the auxiliary circuit to provide the excitation current necessary for the current transformer, so that the error source of the current transformer is eliminated, and accuracy of the current transformer is greatly improved. A 0.001-level high-accuracy current transformer which is insensitive to secondary loads and an open type current transformer with the accuracy degree superior to 0.01level can be developed by using the high-accuracy electronic compensated current transformer.

The invention belongs to the technical field of galvanic corrosion measurement for metal materials, in particular relates to a multi-channel galvanic corrosion measurement device. According to the multi-channel galvanic corrosion measurement device, an SOC (System on a Chip) processor structural design is adopted; the front end of an electrode connection cable is connected with an electrode; the rear end of the electrode connection cable is connected into a voltage/current measurement switching unit; two ends of a front end signal conditioning circuit are bridged with a reference source afterbeing electrically communicated with an A/D (Analog-to-Digital) conversion circuit; the front end of the front end signal conditioning circuit is electrically connected with the voltage/current measurement switching unit; the output end of the A/D conversion circuit is electrically communicated with a main control module after being connected in series with a multi-channel electric isolation unit; an SOC processor is arranged in the main control module; the main control module is electrically connected with a display module, a storage module and a communication module respectively, so that electric information control is realized; and a signal input by a reference electrode is incorporated into the front end signal conditioning circuit after being amplified, so that a signal processing system is formed. The multi-channel galvanic corrosion measurement device has the characteristics of simple overall structure, reliable principle, convenience for use and operation, accuracy in measurement data, flexibility for control and wide application range.

The invention provides a broadband current transformer. The broadband current transformer comprises a detection iron core (1), wherein a detection winding (2), a detection winding copper screen (3), an inner magnetic screen (4), an inner compensation winding (5), an outer magnetic screen (6), an outer compensation winding (7), an outer compensation winding copper screen (8), a secondary winding (9), a secondary winding copper screen (10) and a primary winding (11) are arranged outside the detection iron core (1) from an inner layer to an outer layer in sequence; compensation capacitors (13) are connected at two ends of the outer compensation winding (7) in parallel, and compensation capacitors (14) are connected at two ends of the secondary winding (9) in parallel; and the number of windings of the inner compensation winding (5) is equal to that of the outer compensation winding (7). According to the broadband current transformer, main error sources of the current transformer are eliminated, the capacitive error of the broadband current transformer is reduced, and the measurement accuracy of high-frequency current is improved.

The invention discloses a transformer state detection device. The transformer state detection device is characterized in that according to internal distance changes under various working states of transformers, the internal resistance changes are converted into changes of level waveforms by the aid of independent detection circuits and a level conversion circuit, and the current working states of the transformers are judged according to different level waveforms. The invention further discloses a breaker with the transformer state detection device. Compared with the prior art, the transformer state detection device and the breaker have the advantages that disconnection faults of the transformers can be detected, internal resistance changes of the transformers caused by other faults can be detected accurately, and integral system safety can be improved greatly. The independent detection circuits are used, so that influences of transformer state detection on current signal sampling are eliminated, and current measurement precision of the intelligent breaker is improved.

An optical fiber current transformer includes a broadband light source, a depolarizer, a beam splitter, a temperature acquisition unit, a current acquisition unit, a modulation waveform generating unit, a data processing unit and a calculating compensation unit. The broadband light source is connected with the beam splitter by the depolarizer. A first output of the beam splitter is connected with the calculating compensation unit by the temperature acquisition unit. A second output of the beam splitter is connected with the data processing unit by the current acquisition unit. The data processing unit is connected with the calculating compensation unit. The calculating compensation unit is connected with the current acquisition unit by the modulation waveform generating unit. The optical fiber current transformer uses the temperature-current compensation curve in the calculating compensation unit to synchronously process the temperature and current, thereby improving the accuracy of real-time current measurement.

The invention belongs to the technical field of electric energy quality analysis and discloses an online electric energy quality monitoring system based on an ARM and an FPGA. The online electric energy quality monitoring system comprises an electric energy quality analysis meter, a data collection server, a local monitoring terminal and a remote monitor terminal, wherein the electric energy quality analysis meter is connected with the data collection server, and the local monitoring terminal and the remote monitor terminal are respectively connected with the data collection server; the electric energy quality analysis meter comprises a voltage measurement structure, a first filter circuit, a current measurement structure, a second filter circuit, a frequency tracking module, an analog-digital conversion chip, an FPGA chip and an ARM processor; the voltage measurement structure is connected with the analog-digital conversion chip through the first filter circuit; the current measurement structure is connected with the analog-digital conversion chip through the second filter circuit; the analog-digital conversion chip is connected with the FPGA chip; the first filter module is connected with the FPGA chip through the frequency tracking module; and the FPGA chip is connected with the ARM processor.

The invention discloses a cable type fault detector. The cable type fault detector comprises a short-circuit fault indicator and a zero-sequence current mutual inductor. The short-circuit fault indicator comprises a power-taking current mutual inductor, a measuring current mutual inductor, a CT (Captive Test) power supply circuit, a phase current measuring circuit, a wireless communication module, an MCU (Microprogrammed Control Unit) and a zero-sequence current measuring circuit, wherein the power-taking current mutual inductor is connected with the power supply end of the MCU by virtue of the CT power supply circuit; the measuring current mutual inductor is connected with an I/O (Input/Output) port of the MCU by virtue of the phase current measuring circuit, and used for transmitting a detected phase current transmitting signal to the MCU; the zero-sequence current mutual inductor is connected with the A/D (Analog to Digital) sampling port of the MCU by virtue of the zero-sequence current measuring circuit, and used for transmitting a detected current transmitting signal to the MCU; the serial interface of the wireless communication module is connected with the I/O port of the MCU by virtue of an SPI (Single Program Initiation) bus. The cable type fault detector disclosed by the invention adopts a structural form with a plurality of current mutual inductors to carry out short-circuit and grounding fault detection, thereby effectively improving the current measuring precision and lowering the equipment start-up current.

Apparatus and methods provide a current sensor system including a plurality of current sensors positioned proximate a plurality of conductors. Each conductor is configured to carry a current to be measured. Each current sensor comprises one or more magnetic field sensing elements configured to generate a respective magnetic field signal indicative of a detected magnetic field. The plurality of current sensors includes a first number of current sensors and the plurality of conductors includes a second number of conductors such that the first number is at least one more than the second number. A controller is coupled to receive the magnetic field signal from each of the current sensors and, for each magnetic field sensing element, is configured to characterize a magnetic coupling between the magnetic field sensing element and each of the plurality of conductors.

The invention provides an intelligent molded case circuit breaker and a manipulation method. The intelligent molded case circuit breaker comprises an upper cover, a middle cover, an operating mechanism, a phase system, a base and an intelligent release; the intelligent release comprises a release cover, an intelligent release circuit board, a release base, a connection row, a power supply transformer, a measurement transformer, a magnetic flow unit and a release transfer reset unit. The intelligent molded case circuit breaker has the advantages as follows: (1) the circuit breaker has a doublebreak point structure, and through the design of a movable contact and a static contact in the phase system, the circuit breaker has the advantages of high closing reliability and high opening speed,thereby ensuring the use performance of the circuit breaker. (2) The opening and closing reliability of the circuit breaker is improved by the design of the intelligent release, comprising the designof the magnetic flow, a rocker, a reset member and a mechanism push rod and the like. (3) The intelligent release transformer adopts a double-coil structure, so that the current measurement accuracy is high, which is beneficial to realizing overcurrent release more accurately.

The invention relates to the field of a magnetic core fixing structure assembly of a Hall current sensor, in particular to a magnetic core air gap fixing structure assembly for a core passing type Hall current sensor. The magnetic core air gap fixing structure assembly is characterized in that a fixing hole or a positioning groove is formed in a single magnetic core with an air gap formed by lamination riveting and punching; a non-conductive metal sheet is riveted and punched or welded onto the upper top layer or the outermost upper and lower layers of the single magnetic core; the non-conductive metal sheet is welded onto the outer side surface or the top of the magnetic core air gap position by a single magnetic core with an air gap formed by winding; when the two single magnetic cores with the same dimension or the single magnetic cores with one or even air gaps and one fixing frame or framework is used, the two single magnetic cores with the air gaps are arranged on the upper and lower surfaces of the fixing frame or the framework; the even number of air gaps are in staggered arrangement or symmetrical distribution or uniformly divide the whole magnetic paths; the side surface of the fixing frame or the framework is provided with an insertion groove communicating the air gaps of the magnetic core; the conversion plate is inserted in the insertion groove; a Hall element arranged in the magnetic core air gap is directly connected with a printed circuit board or is connected with the printed circuit board through a conversion plate.

In order to accurately measure three-terminal currents of a triode, a triode annealing effect and the neutron fluence under the pulse neutron irradiation, the invention provides a triode three-terminal current waveform measuring system and method, a triode annealing effect measuring system and method, and a neutron fluence measuring method. According to the invention, under the circumstance that the current of an emitter of a to-be-measured triode is fixed, the response to the pulse neutron by the three-terminal currents of the to-be-measured triode is measured and the bias of the triode is not affected by the photocurrent during the irradiation, so that accurate measurement of the triode annealing effect under the pulsed neutron irradiation and the neutron fluence in an unknown irradiation field.

The invention relates to a method for determining a load current, which is based on conducting a calibration current in a particular manner and on particular calculation methods.