A power distribution monitoring system is provided that can include a number of features. The system can include a plurality of power line sensing devices configured to attach to individual conductors on a power grid distribution network. In some embodiments, the power line sensors can include a split-core transformer. In some embodiments, a power line sensing device is disposed on each conductor of a three-phase network. The sensing devices can be configured to measure and monitor, among other things, current and electric-field on the conductors. Methods of installing, sealing, and protecting the split-core transformers of the power line sensors are also discussed.

A current sensor for measuring an electric current of a bus bar includes a ferromagnetic core and a circuit board. The bus bar extends through the ferromagnetic core. The ferromagnetic core includes a first air gap having a first width and a second air gap having a second width. The first width is greater than the second width. The circuit board includes a single sensor chip or two spatially separated sensor chips. The circuit board positions the sensor chip or the sensor chips relative to the first air gap and the second air gap. The single sensor chip includes two spatially separated magnetic sensing points, or the two sensor chips each include one magnetic sensing point. Each magnetic sensing point is disposed in one of the first air gap or the second air gap.

A health monitor circuit for an electric machine includes a plurality of sensors, a rectifier, a memory device, and a microprocessor. The plurality of sensors includes a current transformer configured to be electromagnetically coupled to an electrical conductor that feeds a stator winding of the electric machine. The rectifier is coupled to the current transformer and is configured to convert an AC signal generated by the current transformer to a DC signal to supply power for the health monitor circuit. The microprocessor is coupled to the memory device and the plurality of sensors. The microprocessor is configured to periodically collect a stator current measurement from the current transformer and write the stator current measurement to the memory device.

Systems, apparatuses, and methods are described for calibration of a current transformer. In some examples, one or more electrical elements may be affected in order to set a calibration of the current transformer. A calibration circuit of the current transformer may be permanently or non-permanently affected according to a calibration code in order to set the calibration of the current transformer. For example, one or more fuses may be burned to lock in a certain configuration of the current transformer.

A clamp sensor includes: a pair of clamp arms that construct a ring-shaped sensor in a closed state and rotate about a rotational shaft provided near base ends of the clamp arms so that other ends of the clamp arms come in to contact and move apart; and a pair of operating arms that extend from the base ends of the clamp arms and are capable, by rotating about the rotational shaft so as to approach each other, of shifting the clamp arms into an open state. The operating arms are formed in arc shapes where, when looking along an axial direction of the rotational shaft, an outer edge of one operating arm and an outer edge of the other operating arm are curved in a same direction.

Adsorbable electromagnetic field auxiliary device for large components, comprises an iron core being adsorbed on the component to be processed with an integral rectangular frame including a pair of lateral sides and a pair of longitudinal sides; lateral sides are installed with electromagnetic coils having opposite magnetic pole pointing to the component. A photoelectric sensor installed on the longitudinal side senses the real-time position of the laser head; the longitudinal opposite sides are each provided with a screw movement device and a brush device; the brush head of the brush device slides on the surface of the component forming a directional electric field; the motor controlled by the central controller adjusts the position of the brush device, so that the two brush heads and the laser head are always in a straight line to ensure the stability of the electric field in the laser processing area and uniformity.

A health monitor circuit for an electric machine includes a plurality of sensors, a rectifier, a memory device, and a microprocessor. The plurality of sensors includes a current transformer configured to be electromagnetically coupled to an electrical conductor that feeds a stator winding of the electric machine. The rectifier is coupled to the current transformer and is configured to convert an AC signal generated by the current transformer to a DC signal to supply power for the health monitor circuit. The microprocessor is coupled to the memory device and the plurality of sensors. The microprocessor is configured to periodically collect a stator current measurement from the current transformer and write the stator current measurement to the memory device.

Systems, apparatuses, and methods are described for calibration of a current transformer. In some examples, one or more electrical elements may be affected in order to set a calibration of the current transformer. A calibration circuit of the current transformer may be permanently or non-permanently affected according to a calibration code in order to set the calibration of the current transformer. For example, one or more fuses may be burned to lock in a certain configuration of the current transformer.

The application provides a current detecting circuit, including a current transformer having a primary winding for receiving a current to be detected and a secondary winding for generating a sampling current; a demagnetizing circuit for demagnetizing the current transformer; a chip selection circuit electrically connected to the demagnetizing circuit, and operably switched between a first mode and a second mode; a sampling circuit electrically connected to the chip selection circuit to sample the sampling current, and outputting a sampling signal to a controller; and a clamping circuit electrically connected between the sampling circuit and the controller, and configured for providing a reference potential. The application further provides a converter including the current detecting circuit.

Current transducer including a housing comprising a coil support, a magnetic core extending between a first end and a second end, and a coil comprising a plurality of windings formed around the coil support. The coil support comprises a core receiving channel within which the magnetic core is inserted, the coil support comprising a radially inner support portion and a radially outer support portion between which the core receiving channel is disposed. The radially inner support portion is slidably movable with respect to the radially outer support portion.