Abstract

The invention relates to a method for classifying electrical sheet that is used to produce an electrical machine and that is available in the form of a strip roll (1), characterized in that: a magnetic flux that changes over time and that causes a shape change of the strip roll (1) and magnetic losses is produced in the strip roll (1) by means of an excitation winding (2) fed by a feeding device (5); the shape change and/or the magnetic losses are measured by means of a measuring device (3, 6, 23) and the measurement signal (21, 22, 24) obtained is fed to an evaluation device (4); and the evaluation device (4) categorizes the electrical sheet in regard to noise emission and/or magnetic losses using the measurement signal (21, 22, 24).

IPC Classes  ?

• G01R 33/04 - Measuring direction or magnitude of magnetic fields or magnetic flux using the flux-gate principle
• G01N 27/90 - Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating magnetic variables for investigating the presence of flaws using eddy currents
• G01N 29/14 - Investigating or analysing materials by the use of ultrasonic, sonic or infrasonic wavesVisualisation of the interior of objects by transmitting ultrasonic or sonic waves through the object using acoustic emission techniques
• B06B 1/08 - Processes or apparatus for generating mechanical vibrations of infrasonic, sonic or ultrasonic frequency making use of electrical energy operating with magnetostriction

Abstract

The invention relates to a method for reducing the noise emission of a transformer, the transformer tank of which is filled with liquid and the tank wall of which vibrates during operation, characterized by the sequence of the following method steps: a.) detecting natural frequency values of the tank wall for at least one excitation frequency; b.) determining at least one eigenmode for which the vibration of the tank wall is composed at an excitation frequency, from the natural frequency values, wherein areas of large curvature are determined on the tank wall; c.) arranging at least one vibration loading device in at least one of said areas; d.) controlling the at least one vibration loading device by means of a control device in order to counteract the vibration of the tank wall.

IPC Classes  ?

• H01F 27/33 - Arrangements for noise damping
• G10K 11/16 - Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
• G10K 11/178 - Methods or devices for protecting against, or for damping, noise or other acoustic waves in general using interference effectsMasking sound by electro-acoustically regenerating the original acoustic waves in anti-phase

Abstract

The invention relates to a device for disassembling a fitting (1) attached to a connecting port (11) of a tank (12), particularly a transformer tank filled with transformer oil, comprising: a drain stopper (2) made of an elastic material; an actuating device (17) by means of which the drain stopper (2) can be inserted through the fitting, opposite an outflow direction, when the fitting is opened, and can be brought into a closure position (19) in an inserted position, in which the drain opening (21) of the connecting port (11) is tightly closed.

IPC Classes  ?

• F16K 7/10 - Diaphragm cut-off apparatus, e.g. with a member deformed, but not moved bodily, to close the passage with inflatable member
• F16K 7/20 - Diaphragm cut-off apparatus, e.g. with a member deformed, but not moved bodily, to close the passage with a compressible solid closure member
• F16K 43/00 - Auxiliary closure means in valves, which in case of repair, e.g. rewashering, of the valve, can take over the function of the normal closure meansDevices for temporary replacement of parts of valves for the same purpose
• F16L 55/134 - Means for stopping flow in pipes or hoses by introducing into the pipe a member expandable in situ introduced axially into the pipe or hose the closure device being a plug fixed by radially deforming the packing by means of an inflatable packing

Abstract

The invention relates to a winding arrangement for a transformer or for a throttle, having an annular winding cover part (6) disposed on the front face of a winding (5), wherein a side surface (22) of the winding cover part (6) overlaps a front surface (10) of the winding (5), wherein the annular winding cover part (6) is designed to be magnetically conductive at least in a partial area (21) and comprises a convex side surface (23) facing away from the winding (5).

IPC Classes  ?

• H01F 27/36 - Electric or magnetic shields or screens

Abstract

The invention relates to a continuously transposed conductor for a winding of an electric machine, particularly for a transformer winding, formed of individual, flat strands (20) insulated from each other and stacked in adjacently disposed strand stacks (3, 4), wherein strands (21) at one end (5, 6) of a strand stack (3, 4) are offset in an offset segment (22, 23), producing a change of the strand (21) from one strand stack to the other strand stack, wherein an insulating element (11, 12) is disposed in each offset segment (22, 23) between adjacent wide surfaces of the strand (21) and the strand stack (3, 4).

IPC Classes  ?

• H02K 3/14 - Windings characterised by the conductor shape, form or construction, e.g. with bar conductors arranged in slots with transposed conductors, e.g. twisted conductors
• H01F 27/32 - Insulating of coils, windings, or parts thereof

Abstract

The invention relates to a transformer core having a stray field shield, comprising at least one core leg (2', 2'', 2''') carrying a winding arrangement (13) and formed from a laminate stack (3), said laminate stack (3) being sealed by end plates (7', 7''), each end plate (7', 7'') being associated with a stray field shield (4', 4'') that comprises coated laminate plates (40', 40''), the layer planes (15) of which are disposed perpendicular to the layer planes (14) of the laminate stack (3), characterized in that the laminate plates (40', 40'') are disposed with laminate plate faces (9', 9'') pointing toward the laminate stack (3) to abut an exterior width surface (8', 8'') of an associated end plate (7', 7'').

IPC Classes  ?

• H01F 27/245 - Magnetic cores made from sheets, e.g. grain-oriented
• H01F 27/36 - Electric or magnetic shields or screens

Abstract

Electrical transformer with unidirectional flux compensation, characterized by the following features: a) the transformer (20) has a soft-magnetic core (4), on which, in addition to a primary and a secondary winding arrangement (1, 2), a compensation winding arrangement (3) is arranged, b) the compensation winding arrangement (3) is connected to a current control device (12, 13), which feeds a compensation current (16, 17) into the compensation winding arrangement (3) in accordance with a control signal (14, 15), which a magnetic field measurement device (30) provides from a measurement of a flux which is interlinked with a current in the primary or secondary winding arrangement, in such a way that the effect of said compensation current in the core (4) is in the opposite direction to a magnetic unidirectional flux (5).

IPC Classes  ?

• H01F 27/34 - Special means for preventing or reducing unwanted electric or magnetic effects, e.g. no-load losses, reactive currents, harmonics, oscillations, leakage fields
• H01F 27/38 - Auxiliary core membersAuxiliary coils or windings

Abstract

Electrical transformer with falling protection for maintenance personnel who are located on an area (6), which can be walked on, of the transformer tank cover (11) while carrying out maintenance work, with the falling protection being in the form of a protection device (2) and being produced from an electrically non-conductive polymer material.

IPC Classes  ?

• H01F 27/02 - Casings
• E04F 11/18 - BalustradesHandrails

Abstract

Insulating material for electrical machines for insulating coiled windings, having a carrier material and adhesive coatings on the front and back of the carrier material, the adhesive coatings being mounted and aligned on the front and back of the carrier material in such a way that in the carrier material in the insulation state a direct frictional connection is developed between the adhesive coatings on the front and back.

IPC Classes  ?

• C09J 7/02 - on carriers

Abstract

Electric transformer (1,19) in a transformer tank (2) with electric contacts and an outer shell (3) enclosing the transformer tank (2), filled with a coolant (4). The coolant (4) in the outer shell (3) can be cooled by a cooling system (20) and coupled to further components (21) in the cooling system (20). The transformer (1,19) is particularly suitable for use (10) in ocean current and tidal power stations.

IPC Classes  ?

• H01F 27/02 - Casings
• H01F 27/12 - Oil cooling
• H01F 27/16 - Water cooling