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WO1991011841A1 - Cycloconvertisseur - Google Patents

Cycloconvertisseur Download PDF

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Publication number
WO1991011841A1
WO1991011841A1 PCT/SE1991/000077 SE9100077W WO9111841A1 WO 1991011841 A1 WO1991011841 A1 WO 1991011841A1 SE 9100077 W SE9100077 W SE 9100077W WO 9111841 A1 WO9111841 A1 WO 9111841A1
Authority
WO
WIPO (PCT)
Prior art keywords
phase
cycloconvertor
reactive power
network
members
Prior art date
Application number
PCT/SE1991/000077
Other languages
English (en)
Inventor
Jörgen GUSTAFSSON
Bertil Klerfors
Original Assignee
Asea Brown Boveri Ab
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 Asea Brown Boveri Ab filed Critical Asea Brown Boveri Ab
Publication of WO1991011841A1 publication Critical patent/WO1991011841A1/fr

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Classifications

    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
    • H02J3/00—Circuit arrangements for AC mains or AC distribution networks
    • H02J3/34—Arrangements for transfer of electric power between networks of substantially different frequency
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
    • H02M5/00—Conversion of AC power input into AC power output, e.g. for change of voltage, for change of frequency, for change of number of phases
    • H02M5/02—Conversion of AC power input into AC power output, e.g. for change of voltage, for change of frequency, for change of number of phases without intermediate conversion into DC
    • H02M5/04—Conversion of AC power input into AC power output, e.g. for change of voltage, for change of frequency, for change of number of phases without intermediate conversion into DC by static converters
    • H02M5/22—Conversion of AC power input into AC power output, e.g. for change of voltage, for change of frequency, for change of number of phases without intermediate conversion into DC by static converters using discharge tubes with control electrode or semiconductor devices with control electrode
    • H02M5/25—Conversion of AC power input into AC power output, e.g. for change of voltage, for change of frequency, for change of number of phases without intermediate conversion into DC by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a thyratron or thyristor type requiring extinguishing means
    • H02M5/27—Conversion of AC power input into AC power output, e.g. for change of voltage, for change of frequency, for change of number of phases without intermediate conversion into DC by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a thyratron or thyristor type requiring extinguishing means for conversion of frequency

Definitions

  • the present invention relates to cycloconvertor equipment for transmision of power between a three-phase electric alternating voltage network with a first operating frequency and a single-phase alternating voltage network with a second operating frequency which is lower than the first frequency, and comprising a cycloconvertor for conversion of the voltage of the three-phase network into an alternating voltage with the second frequency as well as a three-phase alternating voltage terminal for connection to the three- phase network and a single-phase alternating voltage ter ⁇ minal for connection to the single-phase network.
  • the three-phase network usually consists of a three-phase power network with the operating frequency 50 Hz or 60 Hz.
  • the single-phase network may, for example, consist of a railway power. supply system with a operating frequency of, for example, 16 2/3 Hz or 25 Hz.
  • the single-phase network may consist of a single single-phase load, for example an electrical induction f rnace.
  • Such a cycloconvertor may consist of two "direct-voltage" antiparallel-connected three-phase thyristor bridges, the alternating voltage terminals of which are connected to the three-phase network and the "direct voltage terminals" of which are connected to the single-phase network.
  • the "direct voltage” of the bridges is controlled in accordance with a sinusoidal reference, and the cycloconvertor is in this way caused to
  • SUBSTITUTESHEET generate on its single-phase side a sinusoidal alternating voltage. In a manner known per se, this voltage may be controlled with respect to magnitude, phase position __ffl_i frequency. Both active and reactive power may flow in arbitrary directions between the cycloconvertor and the single-phase network.
  • a cycloconvertor of the above known kind exhibits several disadvantages.
  • the single-phase load in the secondary network gives rise to power pulsations in the three-phase primary network with twice the frequency of the secondary network. These power pulsations may have a high amplitude and give rise to harmful voltage variations in the primary network.
  • a cycloconvertor of the above-mentioned kind further generates harmonics with the frequencies
  • , where fp is the operating frequency of the primary network, fs the operating frequency of the secondary network and k 1, 2, 3
  • a possible reactive power, consumed by the secondary network is delivered from the primary network via the cycloconvertor.
  • This reactive power loads the primary network and gives rise to an undesirable voltage drop therein.
  • the reactive power flowing through the cycloconvertor makes it necessary to dimension the cycloconvertor for a higher voltage than what would otherwise have been necessary. In normal operation, therefore, the cycloconvertor voltage is reduced in relation the maximally possible voltage, which causes the cycloconvertor to consume reactive power, which also loads the primary network in an undesirable way.
  • convertors of the kind described in the introductory part of this description are previously known, in which three-phase cycloconvertors are used and in which the secondary network is connected to two of the phase terminals of the cycloconvertor. Further, these prior art systems are provided with controllable reactive power members for symmetrization of the load. In this way, at least some of the above-mentioned disadvantages are eliminated. However, this is achieved at the cost of considerably increased complexity, since in these known systems the cycloconvertor consists of three complete single-phase convertors.
  • the present invention aims to provide cycloconvertor equipment of the kind described in the introductory part of the description, in which
  • the cycloconvertor with two phases on the secondary network side, that is, designing the cyclo- converter such that it generates a two-phase voltage with the frequency of the secondary network.
  • the cycloconvertor On the secondary side the cycloconvertor has two phase terminals as well as one terminal which constitutes the neutral point of the cycloconvertor.
  • the single-phase secondary network is connected to two of the terminals of the cycloconvertor.
  • controllable reactive power members are connected for symmetrization of the load of the cycloconvertor.
  • a third controllable reactive power member is preferably connected in parallel with the terminals to the single-phase network to compensate for the reactive power thereof.
  • Figure 1 shows an example of cycloconvertor equipment according to the invention.
  • Figure 2 shows the configuration of the main circuits of a phase of the cycloconvertor shown in Figure 1.
  • Figure 3 illustrates in the form of a vector diagram the mode of operation of the equipment according to Figure 1.
  • Figure 4a shows equipment according to the invention with the single-phase network connected between a phase and the neutral point of the cycloconvertor, and
  • Figure 4b illustrates the mode of operation of the equipment in the form of a vector diagram.
  • Figure 5a shows alternative equipment and Figure 5b shows in vector form the mode of operation of the equipment.
  • Figure 1 shows an embodiment of cycloconvertor equipment according to the invention for transmission of power from a three-phase power network Nl to a single-phase network N2.
  • the latter may consist of a network in the proper sense of the word, for example a network for power supply of a railway system, or alternatively of a single consumer of single-phase power, for example an induction furnace or similar equipment.
  • the equipment has a three-phase alternating voltage terminal TE1 for connection to the three-phase network and a single-phase alternating voltage terminal TE2 for connection to the single-phase network.
  • the equipment comprises a cyclo ⁇ convertor SC with two mutually identically constructed cycloconvertor phases SCA and SCB.
  • Each cycloconvertor phase consists of (see further Figure 2) two series- connected controllable double bridges .
  • a cycloconvertor transformer TR1 has a Y-connected primary winding Wl connected to the three-phase network and four secondary windings with a D-connected secondary winding (e.g. WAl) and a Y-connected secondary winding (e.g. WA2) for each cycloconvertor phase (A) .
  • the cycloconvertor On its low-frequency side the cycloconvertor has two phase terminals A and B as well as a terminal NP which constitutes the neutral point for the two- phase voltage generated by the cycloconvertor.
  • Each cycloconvertor phase is connected between the neutral point NP and one of the phase terminals .
  • the cycloconvertor is controlled such that at its phase terminals A, B a symmetrical two-phase alternating voltage system with the desired frequency, for example 16 2/3 Hz or 25 Hz, is obtained.
  • the alternating voltage terminals TE2 are connected to the phase terminals A and B via a transformer TR2.
  • a controllable reactive power member is connected, which consists of an inductor LAC, the current and thus the consumed reactive power of which can be varied with the aid of a phase-angle controlled thyristor switch TAC, which comprises two antiparallel-connected thyristor valves .
  • a second controllable reactive power member which comprises a capacitor bank CBC and an inductor LBCl which is phase-angle controlled with the aid of a thyristor switch TBC.
  • An inductor LBC2 is connected in series with the capacitor bank CBC. Together with the capacitor bank the inductor is tuned to the third tone of the operating frequency of the secondary network for reduction of the harmonics generated by the thyristor switch TBC.
  • a third controllable reactive power member is connected between the phase terminals A and B, that is parallel to the single-phase network.
  • this member comprises a capacitor bank CAB as well as a phase-angle controlled inductor LABI, TAB.
  • An inductor LAB2 is connected in series with the capacitor bank CAB and together with the capacitor bank tuned to the third tone of the secondary frequency.
  • a harmonic filter is connected between the terminals A and B and consists of a capacitor bank CF2 as well as the parallel connection of an inductor LF2 and a resistor RF2.
  • an additional harmonic filter consisting of a capacitor bank CF1 and an inductor LF1, is connected to the network.
  • a network switch SW is arranged between the cycloconvertor SC and the network Nl .
  • a control device CD is adapted to control the controllable reactive power members. From an instrument transformer UM the control device is supplied with a signal U2 corre ⁇ sponding to the single-phase voltage, and from a current transformer IM the control device is supplied with a signal 12 which is a measure of the current flowing between the cycloconvertor and the single-phase network.
  • a power measuring device PC calculates, on the basis of the signals U2 and 12, the active component P2 and the reactive component Q2 of the power flowing from the cycloconvertor to the secondary network. The measuring device delivers a signal P2/V2 proportional to the active component a well as a signal Q2 proportional to the reactive component.
  • the latter signal is inverted in an inverter IN2 and supplied to a control pulse device CP3 which delivers control pulses SP3 to the thyristor switch TAB.
  • CP3 control pulse device
  • the control pulse device CP3 controls the thyristor switch such that the reactive power consumed by the inductor LABI is equal to the total input signal -QfAB - Q2 to the control pulse device.
  • the capacitor CAB dominates and the filter may, for example, be assumed to generate a reactive power which is 25 Mvar.
  • QfAB -25 Mvar.
  • the control pulse device controls the current through the inductor LABI such that the inductor consumes 15 Mvar, which means that the total reactive power load from single-phase load plus compensator becomes zero, that is, only the active load remains.
  • the signal P2/V2 from the power measuring device PC is supplied via an inverter INI to a control pulse device CP2 for the thyristor switch TBC.
  • a control pulse device CP2 for the thyristor switch TBC.
  • a constant quantity -QfBC which corresponds to the reactive power consumed by the circuit CBC-LBC2. Since the capacitor dominates, the consumed power is negative, that is the circuit generates reactive power.
  • FIG. 2 shows the configuration of the main circuits of one of the two phases of the cycloconvertor, namely, the phase which is connected to the phase terminal A.
  • the cyclo ⁇ convertor phase is built up from two six-phase controllable double bridges SCAl and SCA2, respectively.
  • the double bridge SCAl consists of the two six-pulse bridges BRAll and BRA12 and the double bridge SCA2 of the six-pulse bridges BRA21 and BRA22.
  • the first two bridges are connected to the secondary winding WAl of the cycloconvertor transformer, and the last two bridges to the secondary winding WA2.
  • the two double bridges operate with a 30° phase shift.
  • the impact on the power system by the cycloconvertor phase will thus be a twelve-pulse impact, that is, the harmonics with the lowest frequency and the highest amplitude are eliminated and the remaining harmonics with low amplitude and high frequency can be damped, in a simple manner, to the desired degree.
  • Each one of the four bridges of the cycloconvertor phase comprises six controllable valves, in Figure 2 shown as conventional thyristor valves.
  • each valve may comprise one single thyristor, or alternatively an arbitrary number of series-connected thyristors, parallel- connected thyristors or series-parallel-connected thyristors.
  • thyristors other controllable elements with a corresponding function may be used.
  • each cycloconvertor phase may be simplified to consist of one single double bridge.
  • Figure 3 shows in vector form the phase voltages UA and UB and the principal voltage UA-B on the secondary side of the cycloconvertor.
  • the two cycloconvertor phases are con ⁇ trolled so as to generate alternating voltages UA and UB between the phase terminals A and B, respectively, and the neutral point NP, which have the same amplitude and are displaced in phase 90° in relation to each other.
  • the current 12 flowing to the single-phase network has the active component Ip and the reactive component I . The latter is compensated for as described above with the aid of the members TAB, LABI, CAB and LAB2.
  • the reactive power member TBC, LBCl, LBC2, CBC is controlled such that its current IQO has the same amount.
  • both I and Is will have the amplitude Ip/ ⁇ 2 and are in phase with the associated phase voltage.
  • the single-phase load is transformed with the aid of the compensator into a symmetrical and purely resistive two- phase load. Since the load on the cycloconvertor is a symmetrical three-phase load, the power pulsations with twice the secondary network frequency occurring in the single-phase network are not transferred to the primary network. Further, the load on the cycloconvertor is purely active. This, per se, entails a reduction of the reactive power load of the primary network. Further, this fact enables a narrower dimensioning of the cycloconvertor with respect to voltage than what has previously been possible, whereby the cycloconvertor is able to operate with a smaller degree of voltage reduction and therefore with a lower intrinsic reactive power consumption than what has previously been possible.
  • These tones have low amplitudes and high frequencies and are therefore easier to damp, where necessary, to the desired degree through filters .
  • the secondary network is connected to the phase terminals of the cycloconvertor.
  • the single-phase network may be connected between a phase terminal and the neutral point of the cycloconvertor.
  • Figure 4a shows such equipment.
  • controllable reactive power devices QCA, QCAB and QC ⁇ are connected between the terminals A and NP, A and B and B and NP.
  • QCA, QCAB and QC ⁇ are connected between the terminals A and NP, A and B and B and NP.
  • Each one of these may consist of a controllable inductor in parallel with a capacitor, that latter tuned to the third tone with the aid of a inductor, in the same way as, for example, the reactive power member LABI, TAB, CAB, LAB2 in Figure 1.
  • the capacitor branch may be omitted, if desired.
  • the control and measuring members and the high-frequency filter CF2, LF2, RF2 are eliminated in Figure 4a.
  • the reactive power members are controlled such that QC AB generates and QC B consumes reactive power.
  • QC A is controlled so as to consume reactive power if II Q
  • IA ICAB ICA + 12
  • IB ICB ⁇ lCAB
  • Figure 5a shows equipment in which the single-phase network is instead connected between the terminals B and NP.
  • the reactive power members are controlled in a corresponding way and such that QCA B consumes and QC A and QC B generate reactive power.
  • the vector diagram for voltages and currents is shewn in Figure 5b. Also in this case, a symmetrical and purely active two-phase load is obtained, the amount of the phase currents being equal to Ip/2.
  • the secondary voltage has been assumed to have a constant amplitude.
  • the quantities QfBC and QfAB used in the control equipment can therefore be approximated as constant quantities.
  • measuring members may instead be arranged to determine these quantities by current and/or voltage measurement.
  • the active and reactive components of the single-phase -load are measured and used for controlling the reactive power members.
  • the phase currents of the cycloconvertor can be measured and a closed-loop control system be adapted to control the reac ⁇ tive power members in dependence on these phase currents such that the currents form a symmetrical two-phase system which is in phase with the secondary voltages of the cyclo ⁇ convertor.
  • one of the reactive power members - TAC, LAC - can only consume reactive power. If desired, all the reactive power members may be designed such that each one of these members can be controlled to consume as well as to generate reactive power.
  • the cyclo ⁇ convertor equipment can then be caused to provide the function described above in case of arbitrary directions of the active and reactive power flows between the cyclo ⁇ convertor and the single-phase network.
  • the reactive power members are controlled to provide complete symmetry of the load of the cycloconvertor and to completely eliminate the reactive power flow through the cycloconvertor.
  • the reactive power members may even be controlled such that a symmetrical reactice three-phase power is generated (or possibly consumed) by the cyclo ⁇ convertor, in which case the cycloconvertor in relation to the primary network may be caused to function as a controlled phase compensator.
  • the members described above for compensation of the reactive component of the single-phase load may be omitted if the power factor of the load is near 1, which may be the case in certain applications, for example when using the cyclo ⁇ convertor equipment for power supply of a railway system.
  • the single-phase transformer TR2 may be omitted if the voltage in the single-phase network is of such a magnitude that the network can be directly connected to the cyclo ⁇ convertor equipment .

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  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Ac-Ac Conversion (AREA)
  • Inverter Devices (AREA)

Abstract

Un cycloconvertisseur (SC) transmet le courant entre un réseau triphasé (N1) et un réseau monophasé (N2) ayant une fréquence de service inférieure à celle du réseau triphasé. Le cycloconvertisseur a une configuration diphasée du côté secondaire et peut donc générer une tension alternative diphasée sur ses bornes (A, B, NP) en regard du réseau monophasé. Le réseau monophasé est raccordé à deux de ces bornes. Entre ces deux bornes (A, B) et la troisième (NP) sont raccordés des éléments à puissance réactive réglables (TAC, LAC; TBC, LBC1, CBC, LBC2). Un dispositif de commande est apte à commander ces éléments afin de les rendre symétriques avec la charge du cycloconvertisseur.
PCT/SE1991/000077 1990-02-05 1991-02-04 Cycloconvertisseur WO1991011841A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
SE9000396A SE465745B (sv) 1990-02-05 1990-02-05 Statisk omformarutrustning foer oeverfoering av effekt mellan ett trefasnaet och ett enfasnaet
SE9000396-3 1990-02-05

Publications (1)

Publication Number Publication Date
WO1991011841A1 true WO1991011841A1 (fr) 1991-08-08

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ID=20378457

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/SE1991/000077 WO1991011841A1 (fr) 1990-02-05 1991-02-04 Cycloconvertisseur

Country Status (2)

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SE (1) SE465745B (fr)
WO (1) WO1991011841A1 (fr)

Cited By (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1997022174A1 (fr) * 1995-12-14 1997-06-19 Abb Daimler-Benz Transportation (Sweden) Ab Dispositif de conversion
WO2000012344A1 (fr) * 1998-08-28 2000-03-09 Abb Ab Dispositif generateur
US6873080B1 (en) 1997-09-30 2005-03-29 Abb Ab Synchronous compensator plant
US6885273B2 (en) 2000-03-30 2005-04-26 Abb Ab Induction devices with distributed air gaps
US6891303B2 (en) 1996-05-29 2005-05-10 Abb Ab High voltage AC machine winding with grounded neutral circuit
US6894416B1 (en) 1996-05-29 2005-05-17 Abb Ab Hydro-generator plant
US6940380B1 (en) 1996-05-29 2005-09-06 Abb Ab Transformer/reactor
US6970063B1 (en) 1997-02-03 2005-11-29 Abb Ab Power transformer/inductor
US6972505B1 (en) 1996-05-29 2005-12-06 Abb Rotating electrical machine having high-voltage stator winding and elongated support devices supporting the winding and method for manufacturing the same
US6995646B1 (en) 1997-02-03 2006-02-07 Abb Ab Transformer with voltage regulating means
US7019429B1 (en) 1997-11-27 2006-03-28 Asea Brown Boveri Ab Method of applying a tube member in a stator slot in a rotating electrical machine
US7046492B2 (en) 1997-02-03 2006-05-16 Abb Ab Power transformer/inductor
US7045704B2 (en) 2000-04-28 2006-05-16 Abb Ab Stationary induction machine and a cable therefor
US7061133B1 (en) 1997-11-28 2006-06-13 Abb Ab Wind power plant
US7141908B2 (en) 2000-03-01 2006-11-28 Abb Ab Rotating electrical machine

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0026374A1 (fr) * 1979-09-28 1981-04-08 Siemens Aktiengesellschaft Dispositif pour le transfert d'énergie électrique de grande puissance d'un réseau d'alimentation triphasé à fréquence plus élevée à un réseau de charge monophasé à fréquence plus basse
DE3150385C2 (de) * 1981-12-17 1985-01-03 Licentia Patent-Verwaltungs-Gmbh, 6000 Frankfurt Statische Netzkupplung für hohe Leistung zur Kupplung eines Dreiphasennetzes höherer Frequenz und eines Einphasennetzes mit niedrigerer Frequenz

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0026374A1 (fr) * 1979-09-28 1981-04-08 Siemens Aktiengesellschaft Dispositif pour le transfert d'énergie électrique de grande puissance d'un réseau d'alimentation triphasé à fréquence plus élevée à un réseau de charge monophasé à fréquence plus basse
DE3150385C2 (de) * 1981-12-17 1985-01-03 Licentia Patent-Verwaltungs-Gmbh, 6000 Frankfurt Statische Netzkupplung für hohe Leistung zur Kupplung eines Dreiphasennetzes höherer Frequenz und eines Einphasennetzes mit niedrigerer Frequenz

Cited By (19)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6052293A (en) * 1995-12-14 2000-04-18 Daimlerchrysler Ag Converter device for connection between a single-phase side on a single or multi-phase side
WO1997022174A1 (fr) * 1995-12-14 1997-06-19 Abb Daimler-Benz Transportation (Sweden) Ab Dispositif de conversion
US6972505B1 (en) 1996-05-29 2005-12-06 Abb Rotating electrical machine having high-voltage stator winding and elongated support devices supporting the winding and method for manufacturing the same
US6936947B1 (en) 1996-05-29 2005-08-30 Abb Ab Turbo generator plant with a high voltage electric generator
US6940380B1 (en) 1996-05-29 2005-09-06 Abb Ab Transformer/reactor
US6891303B2 (en) 1996-05-29 2005-05-10 Abb Ab High voltage AC machine winding with grounded neutral circuit
US6894416B1 (en) 1996-05-29 2005-05-17 Abb Ab Hydro-generator plant
US6906447B2 (en) 1996-05-29 2005-06-14 Abb Ab Rotating asynchronous converter and a generator device
US6919664B2 (en) 1996-05-29 2005-07-19 Abb Ab High voltage plants with electric motors
US6970063B1 (en) 1997-02-03 2005-11-29 Abb Ab Power transformer/inductor
US6995646B1 (en) 1997-02-03 2006-02-07 Abb Ab Transformer with voltage regulating means
US7046492B2 (en) 1997-02-03 2006-05-16 Abb Ab Power transformer/inductor
US6873080B1 (en) 1997-09-30 2005-03-29 Abb Ab Synchronous compensator plant
US7019429B1 (en) 1997-11-27 2006-03-28 Asea Brown Boveri Ab Method of applying a tube member in a stator slot in a rotating electrical machine
US7061133B1 (en) 1997-11-28 2006-06-13 Abb Ab Wind power plant
WO2000012344A1 (fr) * 1998-08-28 2000-03-09 Abb Ab Dispositif generateur
US7141908B2 (en) 2000-03-01 2006-11-28 Abb Ab Rotating electrical machine
US6885273B2 (en) 2000-03-30 2005-04-26 Abb Ab Induction devices with distributed air gaps
US7045704B2 (en) 2000-04-28 2006-05-16 Abb Ab Stationary induction machine and a cable therefor

Also Published As

Publication number Publication date
SE9000396L (sv) 1991-08-06
SE9000396D0 (sv) 1990-02-05
SE465745B (sv) 1991-10-21

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