Improving the main indicators of transformers with twisted one-piece magnetic cores by changing the technology of circular winding turns formation

• Date: 2022
• Main Authors: Avdieieva, O. А., Vakhonina, L. V., Sadovoy, O. S., Stavinskiy, R. A., Tsyganov, O. M.
• Format: Article
• Language: English; Ukrainian
• Published: National Technical University "Kharkiv Polytechnic Institute" and Аnatolii Pidhornyi Institute of Power Machines and Systems of NAS of Ukraine 2022
• Subjects: twisted transformer; one-piece magnetic core; insulating frame; coil; winding
• Online Access: http://eie.khpi.edu.ua/article/view/257780
• Journal Title: Electrical Engineering & Electromechanics

Introduction. With the adoption of standards to reduce losses in transformers it is necessary to change the design of transformers that remain unchanged. Further energy saving is possible with the use of non-traditional technical solutions for the improvement of transformers. Problem. In order to reduce idle losses, the curved magnetic circuits of power transformers are carried out in the form of low-volume circuits. Windings are injected into assembled magnetic conductors by shuttle machines. The shuttle of windings provides technological gaps in winding windows, which results in an increase in size, metal capacity and losses. Goal. Rationale for transformer performance improvement by excluding process gaps in winding windows. Methodology. The definition of the change in transformer indicators is performed using optimization functions of the dimensionless indicators of the technological level. The adequacy of the functions is confirmed by the calculation of the mass of the electromagnetic system and the losses of the transformer. The figures of the compact analogue are calculated from the named serial analogue. Results. The result is a reduction in mass and a loss in the compactness of the transformer. Originality. The improvement of the indicators and the simplification of the winding technology are provided by a change in the design of insulating frames of winding coils. Winding on the rods is ensured by rotating the outer part of the composite insulating frame. Practical significance. Replacement the design of the windings of transformer with power of 40 kVA of 1000 V voltage class with a spatially twisted, small-dimensional magnetic conductor on a compact analogue leads to a reduction in mass and overall dimensions by 15 % and (17-18) %. Efficiency increases by 0.3 %.