An openable toroidal current transformer is intended to close over at least one electrical conductor in which an electrical current to be measured circulates. The current transformer includes a magnetic circuit, and an electrically conducting coil wound around the magnetic circuit and electrically insulated from the magnetic circuit. The coil comprises a single winding or several distinct windings coupled in series. The magnetic circuit comprises a set of wires of magnetic material assembled in the form of a strand, allowing having uniform flexibility in all directions for the magnetic circuit.

A current transformer for a ground fault circuit interrupter (GFCI) can include a core having a closed loop shape having a first side, a second side, and a core opening, and a sense coil wrapped around the core configured to magnetically couple to a plurality of conductors passing through the core opening. The current transformer can include a first magnetic shield disposed on the first side of the core over the sense coil, and a second magnetic shield disposed on a second side of the core over the sense coil.

A power supply device includes a current transformer module capable of adjusting a power induction ratio in order to induce a certain power even when the current of a power line is changed and the current transformer module capable of minimizing the loss in power conversion while providing a certain power even when the current of the power line is changed. The disclosed current transformer module includes a magnetic core constituting a closed loop, a plurality of unit coils wound around the magnetic core, and a switch unit connected to the plurality of unit coils, and the plurality of unit coils include a plurality of unit coils for power-generation.

A dynamic impedance system deployable on a current transformer having a core and at least one winding element is provided. The dynamic impedance system includes a voltage reference module and a dynamic impedance module operably connected to one another. The voltage reference module defines a voltage threshold for regulating an output voltage of the current transformer. The dynamic impedance module regulates the output voltage based on the voltage threshold defined by the voltage reference module to maintain flux induced in the current transformer, thereby avoiding core saturation of the current transformer and enhancing accuracy of measurements.

Provided is a collected current monitoring device. A transformer current acquisition unit acquires a current value I.sub.p of a current flowing through a part of a plurality of transformers. A total collected current calculation unit calculates a current value I.sub.all of a collected current supplied by a plurality of current collectors from the current value I.sub.p by using a following Equation (1): I.sub.all=I.sub.p(M.sub.all/M.sub.p). A collected current acquisition unit acquires a current value I.sub.X of a collected current supplied by the current collector(s) other than one current collector. The collected current calculation unit calculates a current value I.sub.Y of a collected current supplied by the one current collector by subtracting the current value I.sub.X from the current value I.sub.all.

A power electronics circuit is disclosed that includes a switching circuit comprising a first solid-state device coupled in series with a second solid-state device, with at least the first solid-state device comprising a solid-state switch having a gate terminal. The power electronics circuit also includes a current sense transformer positioned between the first and second solid-state devices and configured to sense a current flowing on a conductive trace connecting the first and second solid-state devices, and a controller coupled to the switching circuit and the current sense transformer so as to be in operable communication therewith. The controller is programmed to receive a current sense signal from the current sense transformer indicative of the current flowing on the conductive trace and modulate a gate voltage to the gate terminal of the first solid-state device based on the received current sense signal, so as to control switching thereof.

A current transformer system according to the present invention includes: a sensor CT detachably attached to an electric power transmission/distribution line for detecting the current flowing through the power line by means of electromagnetic induction; a generator CT detachably attached to an electric power transmission/distribution line for generating power by means of electromagnetic induction; and a microprocessor for controlling the sensor CT and the generator CT. According to the present invention, the generator CT is used as the main power source so as to perform independently power supply and facilitate the construction of an additional source in need of additional power.

An apparatus configured for use with a microinverter of an energy management system is provided. For example, apparatus can comprise a cascaded current transformer configuration comprising a first current transformer having a first primary winding configured to couple to a secondary winding of a power transformer of the microinverter and having a first secondary winding coupled to a second primary winding of a second current transformer having a second secondary winding coupled to a measurement device configured to measure a current of the microinverter.

The present technology relates to circuit breaker devices having current sense transformers. The current sense transformer includes a core, a secondary winding, and a primary winding coupled to the power input. The secondary winding includes a first wire wrapped around the core a number of secondary winding turns. The primary winding includes a second wire wrapped around the core a number of primary winding turns. The number of primary winding turns includes a first number of primary winding turns in a first direction and a second number of primary winding turns in an opposite direction that magnetically cancel out the second number of primary winding turns in the first direction to generate an effective number of primary winding turns. The effective number of primary winding turns and the number of secondary winding turns make up a desired turns ratio.

Disclosed embodiments relate to a system for correcting an error, which can correct the error of a measurement device and a transformer data unit through calibration using an emulator even if the measurement device and the transformer data unit are connected in a random combination. In some embodiments, the system for correcting an error includes a measurement device connected to a secondary output line of a transformer to measure current that is output from the transformer, a transformer data unit configured to determine a usage rate and an overload state through calculation of a load amount for a capacity of the transformer in accordance with the current that is measured by the measurement device, and an emulator connected to the measurement device and the transformer data unit to perform error correction between the measurement device and the transformer data unit through performing calibration at least once.