An inductor device includes a first inductor, a second inductor, and at least one switch circuit. The second inductor is arranged to enclose the first inductor, and use a topmost layer metal to resist external interference for the first inductor. The at least one switch circuit is coupled to the second inductor, and is arranged to receive at least one control voltage, wherein the at least one control voltage is arranged to adjust conduction degree of the at least one switch circuit.

A sensor circuit may comprise or otherwise be connected to a transformer. The transformer may comprise a primary winding and a secondary winding. The primary winding may be configurable and/or connectable to sense a current flow in the primary winding. A configurable circuit with an output may be connected to the input of a comparator circuit. The output of the comparator circuit and one or both of the input of the configurable circuit or the output of the configurable circuit may connect across the secondary winding.

A resonant induction wireless power transfer coil assembly designed for low loss includes a wireless power transfer coil, a non-saturated backing core layer adjacent the wireless power transfer coil, an eddy current shield, a gap layer between the backing core layer and the eddy current shield, and an enclosure that encloses the wireless power transfer coil, backing core layer, gap layer and eddy current shield. The gap layer has a thickness in a thickness range for a given thickness of the backing core layer where eddy current loss in the eddy current shield is substantially flat over the thickness range. A thickness of the backing core layer and a thickness of the gap layer are selected where a total power loss comprising power loss in the backing core layer plus eddy current loss over the gap layer is substantially minimized.

The disclosure provides an internal thermal fault diagnosing method for an oil-immersed transformer based on DCNN and image segmentation, including: 1) dividing an internal area of a transformer, and using fault areas and normal status as labels of DCNN; 2) through lattice Boltzmann simulation, randomly obtaining multiple feature images of the internal temperature field distribution of the transformer under normal and various fault state modes, and the fault area serves as a label to form the underlying training sample set; 3) obtaining historical monitoring information of the infrared camera or temperature sensor, and forming its corresponding fault diagnosis results into labels; 4) combining all monitoring information contained in each sample into one image, and then extracting the same monitoring information from the samples in the sample set to form a new image; 5) segmenting image sample and then inputting the same into DCNN for training to obtain diagnosis results.

A transformer arrangement includes a transformer having a winding and a surge arrester arrangement connected thereto. The SAA includes a surge arrester (SA) connected across at least a section of the winding and a switch operable between a closed and open state. In the closed state, SA is electrically connected across at least the section, and in the open state, the SA electrically disconnected from at least the section. The SAA includes at least one further SA .sub.arranged to be connected across at least one further section and at least one further switch, operable between a closed and open state, wherein in the closed state the further SA is electrically connected across the at least one further section, and in the open state, the at least one further SA is electrically disconnected from the further section. A method for electrically connecting/disconnecting the transformer to/from the SAA—is also described.

An external switch actuator includes: a guide tube having a first end and a second end, the first end configured to be attached to a door of a compartment in substantial alignment with both a hole in the door and a switch actuator within the compartment, and the second end configured to be disposed within an interior of the compartment and separated from the switch actuator by a gap when the door is closed; a coupling shaft configured to be operably placed within the guide tube, the coupling shaft having an electrical insulator disposed between an actuator side adapter and a switch side adapter, and a length equal to or greater than a distance between the switch actuator and the hole in the door when the door is closed.

The present disclosure relates to a protective relay detecting disconnection in a circuit comprising a disconnection detection unit including a plurality of nodes connected to both ends of an output of a transformation unit, a reference voltage generation unit forming a reference voltage, and a plurality of resistors forming a voltage dividing resistor and connecting the plurality of nodes and the reference voltage generation unit; a sensing voltage generation unit applying a voltage for forming a predetermined voltage difference with respect to the reference voltage; and a disconnection determination unit connected to a first node, in which the magnitude of a voltage signal applied by the voltage dividing resistor varies depending on whether at least one of the transformation unit and the circuit connected to the transformation unit is disconnected, and detecting whether at least one of the transformation unit and the circuit connected to the transformation unit is disconnected.

An apparatus for identifying a fault in the windings of a distribution transformer, a transformer, and an associated method, said device comprising: a first Rogowski current sensor at a high-voltage incoming current terminal, and a second Rogowski current sensor in tandem at a low-voltage outgoing current terminal and at a low-voltage incoming current terminal; a first conductor of the low-voltage outgoing current terminal, passed through in one direction through the second sensor, and a second conductor of the low-voltage incoming current terminal, passed through in the opposite direction through the second sensor; the first and second sensors generate output signals indicating the primary current and the secondary current; both signals are integrated, generating output signals proportional to the primary current and the secondary current, obtaining a transformation ratio, which is compared with a threshold, and sending a fault signal if said threshold is exceeded.

The invention relates to a method for networked monitoring of at least one transformer (5), wherein the following steps/stages are performed: receiving (110) an electromagnetic signal (210) by a monitoring component (20) at the active transformer (5), the signal (210) being specific to at least one transformer parameter of the transformer (5), carrying out a frequency evaluation (120) based on the received signal (210) by the monitoring component (20), outputting (130) monitoring information (240) about a result of the frequency evaluation (120) to a network (70) for transmission to a processing system (80) for evaluation (140) of the transformer parameter based on the monitoring information (240).

A sensor circuit may comprise or otherwise be connected to a transformer. The transformer may comprise a primary winding and a secondary winding. The primary winding may be configurable and/or connectable to sense a current flow in the primary winding. A configurable circuit with an output may be connected to the input of a comparator circuit. The output of the comparator circuit and one or both of the input of the configurable circuit or the output of the configurable circuit may connect across the secondary winding.