Embodiments of the disclosure relate to detecting turn-to-turn faults in one or more windings of various objects. In one implementation, a fault detector uses a differential protection algorithm to detect a turn-to-turn fault in a winding of a three-phase shunt reactor. Various voltage and current measurements carried out upon the three-phase shunt reactor are used to calculate a difference value between a voltage-based parameter and a current-based parameter. The voltage-based parameter is indicative of a normalized negative voltage imbalance and the current-based parameter is indicative of a normalized negative current imbalance. A turn-to-turn winding fault is declared when the difference value is not equal to zero.

A system for on-line bushing monitoring and geo-magnetically induced current monitoring utilizes a Hall Effect current transducer and obtains the harmonic component of the signals through the measurement of bushing test tap current which provides a more reliable measurement method since the bushings provide a capacitive voltage divider that is not subject to saturation which is a drawback of using current transformers to obtain the signals. The system combines the existing harmonic analysis functions of the bushing monitor measurement system with the measured neutral direct current to provide an economical and efficient system that monitors both bushing condition and GIC conditions with one common monitoring module.

The present invention relates to a device for detecting a partial discharge for a power transformer which detects an electromagnetic signal occurring due to faulty insulation. The device includes an antenna unit receiving electromagnetic waves, an insulator including the antenna unit, a metallic air-tight unit that seals a connector connected to the insulator and connecting a coaxial cable, and the coaxial cable exposed to the outside of the metallic air-tight unit. Thus, it is possible to enhance broadband properties through an internal conductor of a drain valve.

System and method for detecting turn-to-turn faults in one or more windings of various objects are provided. In one implementation, a fault detector receives a set of current measurements associated with a transformer and uses these measurements to execute a procedure for detecting a turn-to-turn fault in the transformer. The procedure can include dividing a steady-state differential current value by a steady-state voltage value to obtain one or more compensating factors, determining a magnetizing current amplitude indicator by multiplying the steady-state voltage value by the one or more compensating factors, determining a compensated differential current value by combining the steady-state differential current value with a modifier value that incorporates the magnetizing current amplitude indicator, comparing the compensated differential current value against a threshold value, and declaring an occurrence of the turn-to-turn fault in the transformer when the compensated differential current value exceeds the threshold value.

A material coating system for an apparatus having a housing configured to contain a fluid is disclosed herein. A multi-layer coating is applied to the housing to mitigate damage caused by external factors. The multi-layer coating includes: a layer of a primer coating having anti-corrosive properties, a layer of a mid coating having mechanical and chemical properties capable of at least partially closing a hole in the housing to avoid fluid leakage and optionally a layer of a top coating having properties that resist ultraviolet radiation from passing therethrough.

A tester for testing a transformer is provided. The tester comprises a primary voltmeter and a plurality of secondary voltmeters. The tester may also comprise an ammeter in series with a voltage source configured to apply voltage to the transformer. The primary voltmeter is configured to measure voltage induced across a primary winding of the transformer, while the secondary voltmeters may simultaneously measure voltage outputs at secondary windings of the transformer. The tester is configured to calculate ratios, saturation curves, and knee points for multiple winding combinations based on the measurements simultaneously obtained by the ammeter and the primary and secondary voltmeters.

For testing a transformer (20) the transformer (20) is emulated by an equivalent circuit (30) and an accuracy of the transformer (20) relative to the equivalent circuit (30) is determined by evaluating a test response of the transformer (20) and is then automatically converted to an operating condition-related accuracy of the transformer (20).

The following steps are performed in order to test a tap changer (20) of a transformer (5; 6) which tap changer is designed to change a transmission ratio of the transformer (5; 6):

generating a test signal which is supplied to a winding (1-3; 10) of the transformer (5; 6) and to the tap changer (20).

Repeatedly actuating the tap changer (20) in order to change the transmission ratio with each actuation.

Determining a curve of an electrical measurement variable (I; I.sub.1; I.sub.2) of the transformer (5; 6) over time (t) respectively during the step of actuating the tap changer (20) depending on the test signal.

automatically illustrating the curves (41, 42) in a temporally-superimposed manner.

The present disclosure relates to an apparatus for predicting power loss of a transformer, and more particularly, to an apparatus for predicting power loss of a transformer, which is capable of predicting power loss by comparing temperature data of the transformer with reference data thereof. An apparatus for predicting power loss of a transformer according to one embodiment of the present disclosure includes a measurement unit configured to measure a temperature of a transformer, a calculation unit configured to calculate temperature data of the transformer on the basis of the measured temperature, a storage unit configured to set and store the reference data of the transformer, and a determination unit configured to determine power loss of the transformer by comparing the temperature data with the reference data, wherein the reference data includes power loss according to the temperature data.

The transformer fault detection apparatus includes an integrated sensor unit for sensing signals through a plurality of sensors located on each of upper and lower drain valves in a transformer. A first possible discharge area calculation unit calculates a first possible discharge area estimated to be a location of a partial discharge source of the transformer, based on arrival times of signals sensed by different sensors located on the upper drain valve. A second possible discharge area calculation unit calculates a second possible discharge area estimated to be the location of the partial discharge source, based on arrival times of signals sensed by different sensors located on the lower drain valve. A final possible discharge area calculation unit calculates a final possible discharge area, based on an overlapping area between the first and second possible discharge areas.