US1659548A

US1659548A - Transformer

Info

Publication number: US1659548A
Application number: US134275A
Authority: US
Inventors: Svend E Johannesen
Original assignee: General Electric Co
Current assignee: General Electric Co
Priority date: 1926-09-08
Filing date: 1926-09-08
Publication date: 1928-02-14
Anticipated expiration: 1945-02-14

Description

Feb. 14, 1928.

S. E. JOHANNESEN TRANSFORMER Filed Sept. s. 1926 2 Sheets-Sheet 1 Inventor: Svend BJohannesen,

His Attorney 2 Sheets-Sheet 2 TRANSFORMER Filed Sept. 8, 1926 S. E. JOHANNESEN Feb. 14, 1928 Inventor-z Sven'd EJohanne sen,

by f

H is Attorn ey.

Patented Feb. 14, 1928.

ITED STATES SVENI) E. JOI-IANNESEN, OF PITTSFIELD, MASSACHUSETTS, ASSIGNOR TO GENERAL ELECTRIC COMPANY, A CORPORATION OF NEW YORK.

TRANSFORMER.

Application filed September 8, 1926. Serial No. 134,275.

My invention relates to transformers. The general object of the invention is to provide an improved magnetic core and winding arrangement for transformers wherein those parts which are subjected to large 'difierences of voltage are Well separated and insulated. Another object of the invention is to provide such a transformer with an improved casing wherein the transformer may be surrounded by a suitable dielectric material, preferably in the form of an inert gas.

Other objects and advantages will appear from the following description taken in connection with the accompanying drawings in which Fig. 1 is a sectional view on the line 11 of Fig. 2 of an encased transformer constructed in accordance with the invention; Fig. 2 is a view on the line 2-2 of Fig. 1; and Fig. 3 is an explanatory diagram showing the magnetic core and winding arrangement. Like reference characters indicate similar parts in the different figures'of the drawings.

The invention will be described as embodied in the transformer shown in Figs. 1 and 2 and which includes two magnetic cores 10 and 11. Each of the cores 10 and 11 is formed of two parallel stacks of rectangular laminations clamped together by end plates 12 and bolts 13. The two stacks of laminations of each pair are separate slightly to provide a ventilating space 1 1. The two cores 10 and 11 are separated by a hollow rectangular insulating member 15 to the opposite faces of which the cores are secured by bolts 16. The member 15, which supports and separately insulates the cores may be formed of any suitable moulded compound.

The high voltage winding is formed in two sections, one section comprising the coils 18 Wound on the core 10 and the other section comprising similar coils 17 wound on the core 11. The coils 17 are connected in series between the

high voltage terminals

19 and 20 and the coils 18- are connected in series between the high voltage terminals 21 and 22 so that, by means of suitable outside connections, the two sections of the high voltage winding may be connected either in series as shown in Figs. 1 and 2, or in parallel, as desired- The four

high voltage terminals

19, 20, 21 and 22 are moulded into the insulating member 15 and may have integral flanges embedded in the insulating member to help prevent leakage past the terminals of gas or other dielectricmaterial surroundmg the transformer. The low voltage winding comprises a single set of coils 23, each of these coils extending through the insulating member 15 and being wound on both cores l0 and 11. These low voltage coils 23 are connected in series between the low voltage terminals 2 1 and 25 of the transformer. 55

Thus the low voltage winding and one section of the high voltage winding are wound on the core 10 and the low voltage winding winding are wound on the core 11.

A. conductive connection 26 from each core to an intermediate point, preferably at or near the center, of the section of the high voltage winding which is wound thereon and the other section of the high voltage serves to establish the voltage of each of the cores. It will be apparent that if these connectlons 26 are at the exact centers of the sections of the high voltage winding and these winding sections are connected in series, then the greatest difierencein voltage that can occur between any point of either core and any point of the high voltage winding cannot exceed one quarter of the voltage between the terminals of this winding.

There will be a voltage difference, of course, 35

between the two cores equal to one half the voltage of the high voltage winding but the cores are well insulated by the insulating member 15 upon which they are mounted.

The two ends of the transformer are en- W insulating member 15 may be secured by integral flanges 28 projectin from the caps and sealed into correspon 'ng grooves in the insulating member. The insulating member 15 and the two end caps 27 constitute a casing which encloses the transformer and.

which may be filled with any suitable dielectric material, preferably an inert gas such as helium or nitrogen or a mixture of such gases. The gas may be introduced into the casing through a valve plug 29 and may be under heavy pressure, if desired, to increase 1ts d1electric strength. The dielectric matcrlal serves not only as insulation for the '24 and are similarly connected to the outer surfaces of the end caps and thus the necessity of openings andbushingsfor the low voltage terminals through the casing is avoided. Withthis arrangement, the voltages of the two end caps differ by that of the low voltage winding but these end caps are effectively insulated by the insulating member 15 to which they are secured.

The principles and advantages of the invention have been explained in connection with an encased transformer having two cores and a corresponding number of sections of high voltage winding. It will be apparent, however, that the invention is not limited, to this number of cores and winding sections and that other chan es may also be made within the scope-oft e invention as defined b the appended claims.

What claim as new and-desire to secure by Letters Patent of the United States mediate point of each of said winding sections and its respective core, said winding of said cores, each of said cores being sections being connected to form one winding of said transformer, and a second winding wound upon all of said cores. '2. A transformer comprising a plurality of separately insulated magnetic cores, a separate winding section wound upon each connected to an intermediate point of its reective winding section, said winding sections being connected to form one winding two magnetic cores mounted respectively upon the opposite faces of said insulating member and insulated from each other thereby, a winding formed in two sections wound respectively on said two cores, each winding section being conductively connected to its core, and a second winding extending through the opening in said insulating member and wound upon both of said cores.

5. A transformer comprising an insulating member having an opening therethrough, 7

two conductive caps secured to the opposite faces of said insulating member to form a caslng therewith to enclose the core and winding elements of said transformer, said transformer having a winding with its two terminals conductively connected to the inner surfaces of said two caps respectively, and two external terminals connected respectively to the outer surfaces of said two caps. 1 6. A transformer comprising an insulating member having an opening therethrough, two conductive caps secured to the opposite faces of said insulating member to form a casing therewith to enclose the core and winding elements of said transformer, a winding having its terminals extending through said insulating member, a second winding having its terminals connected respectively to the inner surfaces of said caps, and two external terminals connected respectively to the outer surfaces of said two caps. In witness'whereof, I have hereunto set myhand; this third (3rd) day of September, 1926. SVEND E. JOHANNESEN.