Патент USA US2107973код для вставки
Feb. 8, 1938. A‘ BAJON ELECTRIC TRANSFORMER FOR HIGH TENSION Filed Sept. 3, 1935 2,107,973 Patented Feb. 8, 193-8v _ 2,107,973 UNITED STATES‘ ' PATENT QFFICE 2,107,973 ELECTRIC TRANSFORMER FOR HIGH TENSION ' Adolphe Bajon, Gcntilly, France, asslgnor to Societe Anonyme "Transformateurs dc Mesure E. Walter”, Gentilly, France, a corporation of France Application September 3, 1935, Serial No. 39,042 . In France December 29, 182*. 2 Claims. The present invention relates to electric trans formers, and chie?y-to, transformers which are (Cl. 175-356) not comprise a like enlargement, owing to dim culties in the insulation. - Immediately around this magnetic circuit is Hitherto-‘the construction of such apparatus ' the low-tension winding C, which is insulated 5 has been attended with di?lculties concerning the from the high-tension winding E-h' an insulat- 5 used for high tension. ' ' insulation ‘oi the windings from one another or ing sleeve member I) having an i ' outer surface arranged coaxially with the mag lack of symmetry of, the parts to be insulated, ’netic circuit. The inner surface of the high-, thus making it‘ necessary to give complicated tension winding also has the form of a hollow inverted cone coaxial with the magnetic circuit. 10 10 forms to'thejinsulating members, to the detri from ground. These di?lculties are due to the ment of their‘ dielectric properties. Various methods have been considered, up to the present, for obviating this drawback. The. dimensions of the magnetic circuit have been increased in 15 order to remove the windings from the unsym » metrical parts of thislatter. Use has also been made of a dielectric such as oil, which readily penetrates between the parts to be insulated and ' at once adapts itself to the most complex forms. However, the ?rst method leads to the use of very aQ bulky and heavy apparatus which is not con cement, while the use of oil does not lead to any great reduction of the sine, and it is always, with the great volume necessary, a source of serious 2,. danger from ?re. ‘ The present invention has for its object the construction of a transformer which does not offer these drawbacks. It is proposed to utilize ‘for this purpose, instead of the closed magnetic m circuit which is in general use, an open magnetic ' circuit, which is symmetrical with reference to an axis. magnetic vcircuit carries windings separated is’ a condenser type insulating sleeve having metallic facings which‘are connected to different points of the windings. The dielectric of the condenserv further assures the insulation of the windings from ground. I ‘.l‘he invention wiil he better understood with reference to the accompanying drawing’. ‘1,; ll‘ieure 1 shows a constructional form oi? trans“ i‘crmer of the high-tension type.‘ ‘ Figure 2 is a diagram of the arrangement of the transformer. m Figure shows the arrangement of the plates dug the marinated core of the transformer. .ieure represents the application oi’ the in» The insulating member D consists of a con denser comprising cylindrical metallic facing parts M, M, which have a parallel position, each being'connected at the lower end to a different point N, N' of the high-tension winding E, in 15 order to distribute the differences of potential of the high-tension winding in the insulating member. _ with the facing parts will be better understood 20 " with reference to Figure 2. In fact, the use of condensers connected as shown in Figure 2, has for its object, on the one hand, to compensate the increase oi.’ current at no load which is due a cross-section of the magnetic circuit, in order > to reduce the loss in the iron due to eddy currents. A It will thus he observed that the construction of 35 this transformer oifers numerous advantages, due to the combination of a straight open magnetic circuit, with an insulating member provided with metallic facing parts, providing units of a con“ denser. _ a high» urinal con~ luctance eight, of an or. hascircuit ,. a ;cylindrical open is magnet very form. high, c circuit an As en» _ the some time obtaining" . could it he as 'ag'eous to use . cilltate the tanner may insulating mg, for error “deed in a cylin u mater: " diameter , only slightly greater than that of larged part is provided at the ‘base in order 5;, to reduce the reluctance, but the top part can ‘40 in fact, the use cl‘ 2. straight magnetic circuit facilitates the insulation of the high~tensiorr winding, by to the dielectric very simple form. that of a circular tube, without making it necessary to increase the dimensions of the 4;; as of the separates. Thus a solid dielectric insulat . - to the open magnetic circuit, as the reduction of 25 this current is advantageous, and on the other hand, to facilitate the distribution, upon the winding, ‘of surges which may come irom the exterior, such as may be caused by lightning, or the like. 30 The core it consists of radial plates arranged in groups, as shovm in Figure 3, which represents he used, * . ‘ Tihe purpose of this insulating member provided windings, and this will only require an em emely small amount of oil. - I 55 2 2,107,973 This arrangement is particularly advantageous in a high-tension transformer, as its general size is proportional to the tension, whereas in ap paratus with closed magnetic circuit employing oil, the size will vary about as the cube of the‘ tension. The progressive distribution or the di?erences of potential in the high-tension winding may be extended to adjacent apparatus. It is particu the distribution of the tension ill larly applicable upon the terminal end of a cable P serving to supply the transformer, and for this purpose it is simply necessary to carry out the arrangement ing base portion adapted to be grounded, a low voltage winding arranged along the bar-like por tion of the core, a high voltage winding having a generally conically shaped interior surface ar ranged over the low voltage winding, a plurality Cl of insulated metal cylinders in stepped coaxial arrangement between the high and low voltage windings to provide capacity elements of a con denser, the inner cylinders being of greater length than the outer cylinders to substantially ?ll the space between the two windings, the area of the outermost cylinder equalling at least one half of the area of the innermost cylinder, and shown in Figure 4-, which represents the possible all of said cylinders extending beyond the two connections between the facing parts :1 which mounted on the cable, and the winding E oi‘ ansforrner. windings at the upper end thereof and the outer cylinders projecting beyond the upper end of measuring e characteristics transrcrr :r,of are ti sasapparatus, follows: as no-load current is smali. accuracy is considerable. ie of th urrent at no load is the arrangement of the plat% ‘I the core, as shown in Figure 3; (c) by the use of condensers connected as shown in Figure ‘2. It is shown in the preceding considerations that on the one hand, this apparatus possesses, 30 in addition to its own advantages, many of those of transformers with closed magnetic circuits and has few or the disadvantages of transformers with open magnetic circuit, in which the degree of accuracy can only be a very small fraction 35 of the apparent power absorbed at no load, as such apparatus has either ‘a very low degree‘ of accuracy or a very large current at no load. I claim: _' 1. In an electrical high tension vsupport type 40 transformer, an open magnetic clrcuit‘dron core having a bar-like vertical portion and alsupport said core. 2. In an electrical high tension support type transformer, an open magnetic circuit iron core having 5. her-like vertical portion and an en~ iarged supporting base portion adapted to be grounded, a low‘ voltace w ‘ring arranged along the bar-like portion of the core, a high voltage winding having a generally sonically shaped in terior surface arranged over the low voltage winding, a plurality or insulated metal cylinders in stepped coaxial arrangement between the h‘gh and low voltage windings to provide capalty elements-of a condenser, the inner cylinders be ing of greater length than the outer cylinders 30 to substantially fill the space between the two windings, the area of the outermost cylinder equalling at least one-half the area of the inner most cylinder, all of said cylinders extending beyond the two windings at the upper end there of and the outer cylinders projecting beyond the upper end of said core, and the successive outer cylinders projecting beyond each preceding inrcr cylinder. 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