CH91411A

CH91411A - Device for damping the third harmonic on three-phase transformers.

Info

Publication number: CH91411A
Authority: CH
Inventors: Cie Aktiengesellschaft Boveri
Original assignee: Bbc Brown Boveri & Cie
Priority date: 1920-09-15
Filing date: 1920-09-15
Publication date: 1921-11-01

Description

       

  Einrichtung zur Dämpfung der dritten Oberwelle an     Dreiphasen-Transformatoren.       Es ist bekannt, zur Dämpfung der dritten  Oberwelle an     Dreiphasen-Transformatoren,     deren Arbeitswicklungen in Stern geschaltet  sind, eine besondere in Dreieck geschaltete  Wicklung     hinzuzufügen.     



  Erfindungsgemäss kann diese besondere  Wicklung fortfallen, wenn man die leitenden       Press-    oder Schutzringe, die ohnehin zum       Zusammenpressen    der     Transformatorspulen     oder zu ihrem     Schutz    gegen steile Spannungs  wellen benötigt werden, in der Weise mit  einander verbindet, dass die aus je einer  Einzelverbindung bestehenden geschlitzten  Ringe zusammen im Dreieck geschaltet werden.  



  In welcher Weise das geschehen kann,  ist aus der Zeichnung ersichtlich, in der a die  genannten Ringe bedeuten. Nach     Fig.    1 ist  nur ein Ring pro Säule benützt, nach     Fig.    2  beide. Als Verbindungen d in     Fig.    2 können       Pressbolzen    verwendet werden, wobei die nicht  als Verbinder dienenden Bolzen gegen die  Ringe elektrisch zu isolieren sind; die Schlitze  c in den Ringen     a        müsset,    dann oben und  unten etwas gegeneinander versetzt werden.

    Die Querverbindungen b können entweder    durch besondere Leiter oder auch durch ohne  hin     vorhandene    Bauteile des     Transformators     gebildet     werden.     



  Ferner     kann        tnan    die drei Ringe     a.    einer  Ebene mitsamt ihren Verbindungen b aus  einem einzigen     Stück    herstellen. Ein solches  Stück kann     gemäss        Fig.3    in Bezug auf alle  drei     Mittelachsen        symmetrisch    ausgebildet  werden, indem die Schlitze c je     zweier    be  nachbarter Ringe vereinigt und in die Mittel  achse verlegt werden.

   Ja man kann sogar  die Schlitze bis auf den Innendurchmesser  der Ringe verbreitern, so dass für die     Drei-          eckentwIcklung    das Bild nach     Fig.    4 ent  steht; solch ein einziger     länglicher,    alle drei       Tranaforrnatorkerne        umfassender,    geschlos  sener Ring hat ebenfalls die     tech ische    Wir  kung einer in Dreieck geschalteten Wicklung,  indem durch ihn die dritte Oberwelle kom  pensiert wird.  



  Die     Dreieckwicklung    kann selbstverständ  lich ausser zur Dämpfung der dritten Ober  welle auch zu anderen Zwecken dienen und  kann auch bei Drosselspulen     Anwendung     finden.



  Device for attenuating the third harmonic on three-phase transformers. It is known to add a special triangle-connected winding to attenuate the third harmonic on three-phase transformers whose working windings are connected in star.



  According to the invention, this special winding can be omitted if the conductive compression or protective rings, which are required anyway to compress the transformer coils or to protect them against steep voltage waves, are connected to one another in such a way that the slotted rings, each consisting of a single connection, are joined together be switched in a triangle.



  How this can be done can be seen from the drawing, in which a denotes the rings mentioned. According to Fig. 1 only one ring is used per column, according to Fig. 2 both. Press bolts can be used as connections d in FIG. 2, the bolts not serving as connectors having to be electrically isolated from the rings; the slots c in the rings a must then be slightly offset against each other at the top and bottom.

    The cross connections b can be formed either by special conductors or by components of the transformer that are not present.



  Furthermore, the three rings a. Create a plane with its connections b from a single piece. Such a piece can be designed symmetrically with respect to all three central axes according to FIG. 3 by combining the slots c of two adjacent rings and relocating them in the central axis.

   Indeed, one can even widen the slots up to the inner diameter of the rings, so that the picture according to FIG. 4 is created for the triangular development; Such a single elongated, closed ring encompassing all three transformer cores also has the technical effect of a winding connected in a triangle in that it compensates for the third harmonic.



  The triangular winding can of course also be used for other purposes in addition to damping the third harmonic and can also be used for inductors.

Claims

PATENT CLAIM: Device for damping the third harmonic on three-phase transformers or choke coils with star-connected windings, by a winding connected in a triangle, characterized by one of the conductive connections of the metallic compression or protection rings that are used to compress or protect against steep voltage waves are required anyway. that the slotted rings, each consisting of a single turn, are connected together in a triangle. SUBCLAIMS: 1.

Device according to patent claim, characterized in that metallic components of the transformer which are already present between the rings are used as connecting lines between the rings. 2. Device according to dependent claim 1, characterized in that a press bolt is used as a connecting line between the two rings of a column, where the slots of the two rings are offset from one another. 3. Device according to claim, characterized in that the rings of a plane are connected and are made of one piece. 4. Device according to dependent claim 3, characterized in that the slots are combined in each case of two adjacent rings. 5.

Device according to dependent claim 4, characterized in that a completely symmetrical body is created by laying the common slots in the longitudinal axis of the pressing piece. 6. Device according to subclaims 3-5, characterized in that the triangular winding is formed by a simple closed ring encompassing the three transformer cores.