A system includes a current transformer including: a primary coil, and a secondary coil including at least two taps; a tap selection circuit; a current measurement apparatus configured to produce an indication of an amount of current flowing in the secondary coil; a power supply electrically connected to a first one of the taps, the power supply configured to receive electrical power from the first one of the taps; and a controller coupled to the power supply and the current measurement apparatus, the controller configured to receive electrical power from the power supply and to control the tap selection circuit based on the indication of an amount of current in the secondary coil.

An integrated circuit includes a first and a second conductive path over a substrate, a coil structure over the substrate, a voltage sensing circuit electrically coupled with the coil structure, and a ferromagnetic structure including an open portion. The first conductive path is configured to carry a first time-varying current and to generate a first time-varying magnetic field. The second conductive path is configured to carry a second time-varying current and to generate a second time-varying magnetic field. The first conductive path and the second conductive path extend through the open portion of the ferromagnetic structure. The first conductive path includes a first conductive line below the ferromagnetic structure, a second conductive line above the ferromagnetic structure, and a first via plug coplanar with the ferromagnetic structure, the first via plug electrically coupling the first conductive line and the second conductive line.

A current transformer (CT) for the purpose of, for example, current measurement, that uses a power line as a first coil and a second coil for measurement purposes, is further equipped with a third coil. Circuitry connected to the third coil is adapted to measure a signal therefrom. The measured signal from the third coil is compared to a signal measured from the second coil and based on the results, internal CT parameters are determined allowing calibration of actual results to expected results thereby providing an improved accuracy. This is especially desirable when using the CT for measurement of the like of current or phase of the primary coil when measurements are adjusted using the newly determined calibration parameters.

A detection device, an inverter, and a detection method are disclosed. The detection device is configured to detect a leakage current flowing through a conductor. The detection device includes a magnetic core, a detection winding and a calibration winding both wound on the magnetic core, a detection circuit, and a calibration circuit. The detection circuit is coupled to the detection winding, and configured to sample a detection signal of the detection winding to obtain a leakage current detection value. The calibration circuit is coupled to the calibration winding, and configured to provide a calibration signal to the calibration winding.

A current-measuring transducer device has a current transducer for measuring an electric current along a conduction path. The current transducer has a magnetic field-sensitive element for converting the magnetic field resulting from the current flow along the conduction path into at least one physical variable and a measuring device for measuring the physical variable. The current transducer device has a coil arrangement with at least one coil for simulating the magnetic field resulting from the current flow along the conduction path. There is also described a method for calibrating a corresponding current transducer and a computer program product for performing the calibration method.

A low-noise current sensor enables large dynamic range current measurements of alternating and direct current flows. The current sensor includes a first substrate, a first conductor, a magnetic flux conductor comprising a first portion orthogonal to the first conductor and a second portion, the second portion penetrating the first substrate, an inductive sensor comprising a first plurality of loops around the second portion of the magnetic flux conductor on the first substrate, wherein the first plurality of loops is orthogonal to the second portion of the magnetic flux conductor, and a Faraday cage that encloses the first plurality of loops and separates the first plurality of loops from the first conductor.

A current sensor includes at least one primary circuit that is intended to conduct the current to be measured, and a secondary circuit containing at least four Neel-effect® transducers, each having a coil and a superparamagnetic core. The current sensor is designed on the basis of a printed circuit board, the primary circuit including at least two distinct metal tracks that are composed of one and the same metal and connected to one another by a via made of a rivet, of a tube or of an electrolytic deposit of the same metal.

An AC/DC leakage detection method, which supports the detection of DC leakage and AC leakage. A DC leakage current and a low-frequency leakage current are measured by means of magnetic modulation technology, an AC signal is measured in the form of pure induction, and two detection modes are performed in a time-sharing manner. A collected leakage signal is converted into a digital signal through an AD converter. By means of the method of the present invention, the processing of a leakage signal is divided into three channels for respectively processing DC leakage, low-frequency AC leakage, and high-frequency AC leakage. The overall effective value of residual current is calculated by integrating results of DC detection and AC detection. The method of the present invention supports the detection of a suddenly increased current; and when there is a suddenly increased current, detection mode switching is performed by detecting the current sudden change of the current.

A current transformer (CT) for the purpose of, for example, current measurement, that uses a power line as a first coil and a second coil for measurement purposes, is further equipped with a third coil. Circuitry connected to the third coil is adapted to inject a known reference signal to the third coil of the CT. The injected reference signal, i.e., current, generates signals in the first and second coils of the CT. The signal generated in the second coil is compared using circuitry attached thereto to the reference signal. Based on the results, and the difference between the expected results and the actual results, updated calibration parameters are determined. These provide improved accuracy when using the CT, for example for measurement of the like of current or phase of the primary coil when measurements are adjusted using the newly determined calibration parameters.

A method includes: step 1: configuring a detection state to be a pure induction mode with no voltage, keeping this mode for t1ms; step 2: configuring the detection state to be a mode of positive and negative saturation excitation square waves, keeping this mode for t2 ms; step 3: when a duration of each mode ends, outputting a characteristic quantity based on sampling data through an algorithm module, and processing the characteristic quantity by a software to complete a state determination; and step 4: in case of a sudden large current, adjusting the detection state to a new detection mode, to respond to the sudden large current, and the software performing process after data collection is completed and a process performed by the algorithm module is completed.