DE939884C - Device for frequency doubling by means of premagnetized chokes - Google Patents

Device for frequency doubling by means of premagnetized chokes

Info

Publication number
DE939884C
DE939884C DEL1599A DEL0001599A DE939884C DE 939884 C DE939884 C DE 939884C DE L1599 A DEL1599 A DE L1599A DE L0001599 A DEL0001599 A DE L0001599A DE 939884 C DE939884 C DE 939884C
Authority
DE
Germany
Prior art keywords
phase
chokes
short
premagnetized
frequency doubling
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
DEL1599A
Other languages
German (de)
Inventor
Werner Dr-Ing Habil Kraemer
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Licentia Patent Verwaltungs GmbH
Original Assignee
Licentia Patent Verwaltungs GmbH
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Licentia Patent Verwaltungs GmbH filed Critical Licentia Patent Verwaltungs GmbH
Priority to DEL1599A priority Critical patent/DE939884C/en
Application granted granted Critical
Publication of DE939884C publication Critical patent/DE939884C/en
Expired legal-status Critical Current

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Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F38/00—Adaptations of transformers or inductances for specific applications or functions
    • H01F38/02—Adaptations of transformers or inductances for specific applications or functions for non-linear operation
    • H01F38/04—Adaptations of transformers or inductances for specific applications or functions for non-linear operation for frequency changing

Landscapes

  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Nonlinear Science (AREA)
  • Ac-Ac Conversion (AREA)
  • Supply And Distribution Of Alternating Current (AREA)

Description

Gegenstand des Hauptpatents ist eine Anordnung zur Umformung von Mehrphasenstrom gegebener Frequenz in Einphasenstrom doppelter Frequenz mittels gleichstromvormagnetisierter Drosseln, bei der zwei Sätze derartiger Drosseln in einer Schaltung nach Art der Scott-Schaltung derart an das Mehrphasennetz angeschlossen sind, daß das Mehrphasennetz bei symmetrischer telastung seiner Phasen eine Einphasenspannung doppelter Frequenz liefert, deren Kurzschlußstrom mittels der Gleichstromvormagnetisierung steuerbar ist. Diese Einriohtwng wird vorzugsweise für Schweißzwecke und für den Betrieb elektTischer Ofen verwendet.The subject of the main patent is an arrangement for converting multiphase electricity given frequency in single-phase current with double frequency by means of direct current bias Chokes, in which two sets of such chokes in a circuit of the Scott circuit are connected to the polyphase network in such a way that the polyphase network With symmetrical loading of its phases, a single-phase voltage of double frequency supplies whose short-circuit current can be controlled by means of the direct current bias is. This device is preferably used for welding purposes and for operating electrical appliances Furnace used.

Es hat sich nun herausgestellt, daß bei einem derartigen- Frequenzwandler im Primärstrom eine Oberwelle von der nächsthöheren Ordnungszahl der Sekundärfrequenz auftritt, die dreiphasig und symmetrisch auf die drei Primärphasen verteilt ist. Da diese Oberwelle bei schwachen Netzen die Spannungskurve deformieren kann, wird erfindungsgeriläß vorgeschlagen, sie über einen zu den primären dreiphasigen Anschlußleitungen des Frequenzwandlers parallel geschalteten Drehstromkondensator kurzzuschließen und damit vom Netz fernzuhalten. Hierzu kann der zur Verbesserung des Leistungsfaktors meist vorhandene Drehstromkondensator mit verwendet werden.It has now been found that with such a frequency converter in the primary current a harmonic of the next higher ordinal number of the secondary frequency occurs, which is three-phase and symmetrically distributed over the three primary phases. Since this harmonic can deform the voltage curve in weak networks According to the invention it is proposed to use one of the primary three-phase connection lines of the frequency converter to short-circuit the three-phase capacitor connected in parallel and thus to keep it away from the network. This can be done by improving the power factor mostly existing three-phase capacitors can also be used.

Dem Kondensator wird zweckmäßig eine Drehstromdroissel vorgeschaltet, die so bemessen ist, daß ihre Phaseninduktivität mit der kapazitiven Phaseninduktivität in bezug auf die betreifende primäre Oberwelle in Resonanz ist. Dafür die Grundwelle der induktive Widerstand der Drossel um die quadrierte Ordnungszahl der Oberwelle kleiner als der kapazitive Widerstand des Kondensators ist, wird die resultierende Grundwellenkapazität durch die Drossel nwr unwesentlich geändert. In der Zeichnung ist die Schaltung eines derartigen Ausführungsbeispiels der Erfindung dargestellt. Mit U V W sind die dreiphasigen Anschlußleitungen .des Frequenzwandlers F bezeichnet, von dem sekundärseitig die einphasige Wechselspannung Uz von doppelter Netzfrequenz abgenommen wird. Parallel zu den dreiphasigen Primärleitungen ist der aus dem D@reiphasenkondensator K und der vorgeschalteten Drehstromdrossel D bestehende Resonanzkreis für die kurzzuschließenden Oberwellen geschaltet.A three-phase inductor is expediently connected upstream of the capacitor and is dimensioned such that its phase inductance is in resonance with the capacitive phase inductance with respect to the primary harmonic in question. If the fundamental wave of the inductive resistance of the choke is smaller than the capacitive resistance of the capacitor by the squared ordinal number of the harmonic, the resulting fundamental wave capacitance is changed insignificantly by the choke nwr. The drawing shows the circuit of such an exemplary embodiment of the invention. U V W denotes the three-phase connection lines of the frequency converter F, from which the single-phase alternating voltage Uz of twice the mains frequency is taken on the secondary side. The resonance circuit for the harmonics to be short-circuited, consisting of the three-phase capacitor K and the upstream three-phase choke D, is connected in parallel to the three-phase primary lines.

Claims (4)

PATENTANSPRÜCHE: 1: Einrichtung zur Frequenzverdoppelung mittels vormagnetisierter Drosseln mit dreiphasiger Speisung aus einem Drehstromnetz mach Patent 931 541, dadurch gekennzeichnet, daß parallel zu den primären dreiphasigen Anschlußleitungen des Frequenzwandlers (F) ein Drehstromkondensator (K) zum Kurzschließen der primärseitig auftretenden dreiphasigen Oberwellen geschaltet ist. PATENT CLAIMS: 1: Device for frequency doubling by means of premagnetized Chokes with three-phase supply from a three-phase network make patent 931 541, characterized in that in parallel with the primary three-phase connection lines of the frequency converter (F) a three-phase capacitor (K) for short-circuiting the primary side occurring three-phase harmonics is switched. 2. Einrichtung nach Anspruch 1, dadurch gekennzeichnet, daß der Drehstromkondensator zum Kurzschließen der primärseitig auftretenden dreiphasigen Oberwellen gleichzeitig zur Blin:dstromkompensation dient. 2. Device according to claim 1, characterized in that the three-phase capacitor for short-circuiting the primary side occurring three-phase harmonics is used at the same time for reactive current compensation. 3. Einrichtung nach Ansprüchen 1 und 2, dadurch gekennzeichnet, .daß jeder Phasenkapazität eine solche Induktivität vorgeschaltet ist, daß der so gebildete Schwingungskreis für die jeweils kurzzuschließende Oberwelle in Resonanz ist. 3. Device according to Claims 1 and 2, characterized in that each phase capacitance such an inductance is connected upstream that the oscillation circuit thus formed is in resonance for the respective harmonic to be short-circuited. 4. Einrichtung nach Anspruch 3, dadurch gekennzeichnet, daß die drei Induktivitäten zu einer Drehstromdrossel vereinigt werden.4. Set up after Claim 3, characterized in that the three inductances form a three-phase choke be united.
DEL1599A 1950-04-04 1950-04-04 Device for frequency doubling by means of premagnetized chokes Expired DE939884C (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
DEL1599A DE939884C (en) 1950-04-04 1950-04-04 Device for frequency doubling by means of premagnetized chokes

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DEL1599A DE939884C (en) 1950-04-04 1950-04-04 Device for frequency doubling by means of premagnetized chokes

Publications (1)

Publication Number Publication Date
DE939884C true DE939884C (en) 1956-03-08

Family

ID=7255475

Family Applications (1)

Application Number Title Priority Date Filing Date
DEL1599A Expired DE939884C (en) 1950-04-04 1950-04-04 Device for frequency doubling by means of premagnetized chokes

Country Status (1)

Country Link
DE (1) DE939884C (en)

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