SU1555713A1 - High-voltage high-frequency transformer - Google Patents

Abstract

The invention relates to electrical engineering and can be used as part of high-power charging devices and in power supplies of electrophysical devices. The purpose of the invention is to increase reliability by increasing cooling efficiency. The toroidal magnetic core 1 is enclosed by a hollow cooler consisting of an outer 2 and an inner 3 hollow cylinders and end copper washers 4 and 5, insulated from the ends of the magnetic core by dielectric rings 6. The foil walls of the cylinders 7 span the magnetic core and distance each other with annular elements 8. Each cylinder along generators are coupled with nozzles 9, 10 and 11, 12 located coaxially and separated by hermetic partitions 13 along the height of the magnetic circuit 1. Such a cooling system allows to increase the intensity of cooling any and increased reliability. 1 hp f-ly, 5 ill.

Description

A ladder consisting of the outer 2 and inner 3 hollow cylinders and end copper washers 4 and 5, insulated from the ends of the magnetic core by dielectric rings 6. The foil walls of cylinders 7 cover the magnetic conductor and distance themselves between the annular elements 8, Each

the cylinder along the generatrix is conjugated with nozzles 9,10 and 11,12, located coaxially and separated by hermetic partitions .13 along the height of the magnetic circuit 1. Such a cooling system allows increasing the cooling intensity and increasing the reliability of operation. 1 hp f-ly, 5 silt

The invention relates to electrical engineering, in particular, to high-frequency transformers with solid insulation and intensive cooling, which can be used as part of high-power charging devices and in power supplies of electrophysical devices.

The purpose of the invention is to increase the reliability of the transformer by increasing the cooling efficiency.

Fig. 1 shows a high-voltage high-frequency transformer in Fig. 2 a diagram of the arrangement of the leads and the connections; on fig.Z - cooler magnetic circuit, figure 4 - section aa on fig.Z; figure 5 - section bb in figure 3.

The toroidal magnetic core 1 is enclosed by a hollow cooler consisting of an outer 2 and an inner 3 hollow cylinders and end copper washers 4 and 5, insulated from the ends of the magneto-conductor by dielectric rings 6. The foil walls of the cylinders 7 tightly enclose the magnetic core and are spaced between themselves by ring elements 8 Each cylinder along the forming interface with two nozzles 9, 10 and 11, 12 located coaxially and separated by sealed partitions 13 along the height of the magnetic circuit. The foil cylinders are sealed at the ends by soldering on the annular protrusions of 14 corresponding end washers. Nozzles are made with longitudinal slots 15, equal to the height of the magnetic circuit and oriented orthogonally sealed partitions through which the refrigerant enters the cylindrical cavity of the cooler.

A layer of solid insulation 16 is applied to the cooler along the entire perimeter of the magnetic circuit. Secondary high-voltage winding 17 can be single and multi-layered. Over the winding

0

0

g

35 40

55

solid insulation 18, which also covers the entire perimeter of the magnetic core, is laid to the floor of the primary winding 19, while sector 20 (tf 30 °) remains free from windings. In this sector, refrigerant supply pipes and high-voltage terminals 21 and 22 of the secondary winding are installed. At the border of the insulating sector 23, primary winding pins are installed, combined with fittings 24 for coolant supply. A polymer insulator 25, which functions as a transformer casing, is formed over the primary winding, and a monolith or mono therm type insulator 26 is applied over the supply and discharge connections of the refrigerant.

The transformer works as follows.

The terminals of the primary winding are connected to an autonomous inverter (f 1-10 kHz). The change in the magnetic flux in the toroidal magnetic core 1 induces a high-frequency emf in a multilayer secondary winding 17, the terminals of which 21 and 22 are installed in the insulating sector 20 (FIG. 2).

In the high-frequency mode, the heat loss is localized in the toroidal magnetic core, in the volume of solid insulation — a type of monolith or monoterm, and in the copper of the primary winding. With large values of the transformation ratio characteristic of a high voltage transformer with a power of ten kilowatts and the optimal choice of current density, losses in the secondary winding are less than losses in the volume of solid insulation.

Liquid refrigerant, such as distilled water, is supplied at a predetermined rate and flow rate through pipes 9 and 11 into cylindrical heat exchangers and through fittings 24 into the hollow primary winding. Coolant, under515

driven through pipe 9, circulates through a cylindrical cavity, which is partitioned by annular ribs 8, and exits the working volume through a longitudinal slot on pipe 10.

Separate normalization of speed and coolant flow rate through the cross-section of the outer 2 and inner 3 HOLLY CYLINDERS AND SEM

The primary winding 19 permits alignment of the temperature field gradients in the insulation, windings, and magnetic circuit. Ethylene glycol or freon can also be used as a refrigerant.

Toroidal magnetic circuit 1 mo

It can be made of permallo, cold-rolled steel or amorphous iron. The secondary winding 17 and sector 20 are insulated with glass mica tape. After crimping and heat treating the high-voltage winding, the primary winding is assembled to the external floor, which may consist of separate half-turns connected by couplings. The cylindrical coolers of the transformer in the foil variant are sealed by soldering to form a monoblock with pipes 9-12.

 For a permallo 50 NTs magnetic circuit with dimensions of 130/180 mm, the loss at a frequency of 51 kHz is l-400 watts. Overheating of the magnetic circuit does not exceed 100 ° С with water consumption

v 1 l / min

When using amorphous steel, the loss in the core decreases by 3-4 in this case, the loss in isolate exceeds the loss in the core, the inversion of heat flux occurs in the design of the transformer. In this mode, cylindrical coolers 2 and 3 preferentially remove heat from the volume of solid insulation 16, 18 and 25.

The midpoint of the secondary high-i voltage winding can be connected to the head duct 1 and the cylindrical coolers 2 and 3. In this case, the sockets 9 and 11 are insulated to half the operating voltage. The high-voltage terminals 21 and 22 of the secondary winding and the nozzles 9 and 11 can be mutually orthogonal with displacement relative to the plane of symmetry within the insulating sector 20, the choice of the magnitude of which (angle

times and

type of term can be term 1

Q

depends on the set output voltage level with

The positive effect of the application of the invention is due to the constructive coordination of the complex requirements for transformers that form a high voltage at high frequency and are made with dry insulation. The use of three independent heat exchangers operating in the regime of forced pumping of fluid, made in the form of thin-walled cylinders from copper

5 foils covering the toroidal magnetic core and the external hollow primary toroidal winding allows adaptive control of heat flows in the working

0 volume and gradient alignment of the temperature field. This makes it possible to increase the reliability of the insulation and the transformer as a whole, since, under the simultaneous action of an intense electric and thermal field (high-frequency losses in the dielectric), the breakdown of the insulation often has a thermal nature.

Transformer can be used

0 when creating small-sized power supply systems for electrophysical devices, for charging capacitive drives and in power supplies of technological installations in the voltage range 2035

50 kV, frequencies of 1-10 kHz and power up to ten kilowatts.

F

five

formula from i: 1. High-voltage high-frequency transformer containing a toroidal magnetic circuit, on which a secondary winding with a solid insulation is located and there is a sector not occupied by a winding in which high-voltage leads are mounted, an external primary winding that distinguishes ™ with the fact that , in order to increase reliability by increasing cooling efficiency, it has a metal cooler, made in the form of two cylinders with hollow walls and end washers, insulated by dielectric rings from magnesium oprovoda cylinders conjugate along generators each with two nozzles, arranged coaxially and capable of longitudinal slits and sealed septa, equal height and oriented magnetic ortogo0

five

gb

Hi

Shg $

Editor N. Tupitsa

Compiled by V. M Snikova

Tehred A. Kravchuk Proofreader N. Revsk

Order 556

Circulation 455

VNIIPI State Committee for Inventions and Discoveries at the State Committee on Science and Technology of the USSR 113035, Moscow, Zh-35, Raushsk nab. 4/5

Production and Publishing Combine Patent, Uzhgorod, st. Gagarin, 101

Figure 1 8-6

FIG. five

Subscription

Claims (2)

The claims I 1. High-voltage high-frequency 49 is a transformer containing a toroidal magnetic circuit on which a secondary winding with solid insulation is located and there is a sector not occupied by a winding in which 45 high-voltage leads are installed, an external primary winding, distinguishing Y-. with the fact that, in order to increase reliability by increasing the cooling efficiency, it has a metallic 50th cooler, made in the form of two cylinders with hollow walls and end washers, insulated by dielectric rings from the magnetic circuit, the cylinders are conjugated along each forming with two nozzles arranged coaxially and made with longitudinal slots and sealed within the insulating sector 20, the choice of the magnitude of which (angle) is made by partitions equal to the height of the magnetic circuit and oriented orthogonally, a metal cooler is installed on the magnetic circuit, and pipes for supplying and withdrawing refrigerant are located in the magnetic circuit sector not occupied by windings. 2. The transformer according to claim 1, which has a function on the cooler cylinders. built-in spacer ring elements, cooler cylinders are made of copper foil, and the primary winding is made of pipe with fittings for refrigerant supply, spacer ring elements are installed ¢ 7 // 2. ί Fig 5