WO1994024622A1 - Systeme de compensation serie commande par thyristor blocable - Google Patents

Systeme de compensation serie commande par thyristor blocable Download PDF

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Publication number
WO1994024622A1
WO1994024622A1 PCT/US1993/011509 US9311509W WO9424622A1 WO 1994024622 A1 WO1994024622 A1 WO 1994024622A1 US 9311509 W US9311509 W US 9311509W WO 9424622 A1 WO9424622 A1 WO 9424622A1
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WO
WIPO (PCT)
Prior art keywords
turnoff
series
thyristor
switching device
capacitor
Prior art date
Application number
PCT/US1993/011509
Other languages
English (en)
Inventor
Stig L. Nilsson
Narain G. Hingorani
Original Assignee
Electric Power Research Institute
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 Electric Power Research Institute filed Critical Electric Power Research Institute
Publication of WO1994024622A1 publication Critical patent/WO1994024622A1/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
    • H02J3/18—Arrangements for adjusting, eliminating or compensating reactive power in networks
    • H02J3/1807—Arrangements for adjusting, eliminating or compensating reactive power in networks using series compensators
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E40/00—Technologies for an efficient electrical power generation, transmission or distribution
    • Y02E40/30—Reactive power compensation

Definitions

  • the present invention relates generally to a series compensation system for inserting a series capacitance in a transmission line during a heavy load period, and more particularly to a turnoff thyristor controlled series compensation system.
  • GTO gate turnoff
  • This system improved on conventional series compensation systems by using a thyristor switch arrangement comprising a thyristor switch in parallel with a series capacitor bank.
  • the capacitor bank comprises a plurality of parallel and series connected capacitor modules.
  • the thyristor switch is connected in parallel with a single or several sections of parallel-connected capacitors.
  • the thyristor switch has at least one thyristor valve, or several series connected thyristor valves.
  • Each thyristor valve is a single pair of conventional thyristors connected in antiparallel.
  • the number of thyristor valves in a single switch is selected to provide a voltage rating matching the voltage rating of the capacitor section across which the switch is connected.
  • the thyristors fire sequentially to bypass the transmission line current around the capacitor bank. If several capacitor sections and thyristor switches are used, the load current may be bypassed around certain capacitor sections by firing only a portion of the total thyristor switches.
  • Each thyristor valve may have overvoltage protection, such as a gapless metal oxide arrestor, in parallel with the valve. Alternatively, a single arrestor may be connected across the entire thyristor switch, rather than across each thyristor valve, or combinations of the single and multiple valve arrestors may be used.
  • the thyristor valves also include conventional snubber circuits, or current limiting reactors.
  • Figs. 8-10 are waveforms with respect to time (t) illustrating the operational limitations of this earlier series compensation system employing conventional thyristor switches.
  • Fig. 8 shows three concurrent graphs of the line current, the capacitor current, and the capacitor or switch voltage.
  • the time at which the thyristor switch is turned off is shown by the vertical dashed line extending between the graphs.
  • turning on the thyristor switch causes a severe DC (direct current) offset to the AC (alternating current) voltage waveform across the capacitor and switch.
  • This severe DC offset occurs because a conventional thyristor switch can only interrupt the current flow through the switch at a zero crossing of the current waveform, as shown by the intersection of the dashed vertical line and the top graph of Fig. 8.
  • the DC offset causes the peak voltage to reach up to twice the nominal value, indicated as 2pu (per unit) in Fig. 8.
  • the capacitors in the series capacitor bank must be designed to withstand twice the rated peak voltage of the transmission line. Such required over-design drastically increases the initial cost of the capacitor bank.
  • Fig. 9 shows concurrent graphs of the line current, capacitor voltage, and the switch current.
  • the time at which the conventional thyristor switch is turned on is indicated by the vertical dashed line linking the graphs together.
  • the line current is bypassed through the thyristor switch and around the capacitor.
  • the thyristor switch can begin conducting at any time during the current cycle, it is preferably turned on at or close to a zero crossing of the voltage waveform, as shown by the intersection of the dashed line and the middle graph of Fig. 9. Turning the thyristor switch on at a voltage zero crossing avoids large surge currents caused by discharging the capacitor through the thyristor.
  • the high frequency transients known by those skilled in the art to be associated with the capacitor bypass switching operation have been omitted to simplify and clarify the graphs.
  • FIG. 10 concurrent voltage and current graphs are shown for two conventional thyristor switches, each in parallel with one or more series connected capacitor bank sections.
  • the "first capacitor” refers to the bank section(s) in parallel the first switch
  • the “second capacitor” 1 refers to the bank section(s) in parallel with the second switch.
  • the second switch extends across twice the number of capacitor bank sections than does the first switch.
  • the second switch has twice the voltage magnitude of the waveform shown for the first capacitor voltage, as shown by the dashed waveforms in Fig. 10.
  • the Fig. 10 graphs show the performance characteristics of sequentially turning off the two thyristor switches to sequentially insert the capacitor bank sections in series with the transmission line. Initially, only the first switch is open. The first switch remains open allowing current to flow through the first capacitor bank section(s) throughout the entire time period shown in the Fig. 10 graphs.
  • the dashed vertical line extending between each of the five graphs indicates the time of operating the second switch to open. During the time to the left of the vertical dashed line, the second switch is closed, and during the time period to the right of the dashed line the second switch is open.
  • the second thyristor switch in the Fig. 10 example must be turned off at a natural zero crossing of the line current waveform. This operation causes a temporary voltage bias or DC offset component which is superimposed over the AC waveform. This undesirable DC offset transiently increases the voltage across the capacitors associated with the first switch which are already operating when the second thyristor switch is turned off (see the middle graph in Fig. 10) .
  • the magnitude of the overvoltage experienced by the first capacitor bank section depends upon the relative size of the capacitors used in the circuit. With unequally sized capacitors, the overvoltage can be critical, often requiring operation of the overvoltage protection for the effected capacitor.
  • FIG. 10 illustrates the overvoltage experienced at the second capacitor bank section after the second switch is opened.
  • the dashed lines in the middle and last graphs of Fig. 10 show the proper location of the capacitor voltage waveforms without the DC offset.
  • a series compensation system for compensating a transmission line having a line current flowing therethrough.
  • the system has a capacitor for placing in series with the transmission line, and a turnoff switching device in parallel with the capacitor.
  • the switching device turns on to bypass the line current around the capacitor, and selectively turns off to insert the capacitor in series with the transmission line so current flows through the capacitor.
  • the switching device may be turned off at any time during a cycle of the current waveform as it flows through the switching device.
  • a method for compensating a transmission line during heavy load periods to prevent unacceptable undervoltage conditions.
  • An overall object of the present invention is to provide an improved series compensation system, including an apparatus and method, for compensating the impedance of a transmission line during a heavy load period.
  • a further object of the present invention is to reduce the voltage stress on a capacitor which is placed in series with the transmission line to provide series compensation.
  • Another object of the present invention is to eliminate a DC offset component in the voltage of a capacitor when it is switched in series with a transmission line for compensation.
  • An additional object of the present invention is to provide a series compensation system which may be used with advanced switching strategies to damp subsynchronous oscillations in the shafts of a turbine-generator unit coupled to the transmission line.
  • Still another object of the present invention is to provide a more economical series compensation system than available in the past.
  • Fig. 1 is a single line schematic block diagram of one form of a series compensation system of the present invention
  • Fig. 2 is a schematic diagram of one form of a turnoff switch for use in the system of Fig. 1;
  • Fig. 3 is a schematic diagram of an alternative switch to that shown in Fig. 2;
  • Fig. 4 is a single line diagram of an alternative switch to that shown in Fig. 2;
  • Fig. 5 are graphs of the concurrent voltages and currents with respect to time (t) associated with the operation of the system of Fig. 1;
  • Fig. 6 is a schematic diagram illustrating one manner of operating the system of Fig. 1;
  • Fig. 7 are graphs of the concurrent voltages and currents with respect to time (t) associated with an alternative manner of operating the system of Fig. 1;
  • Figs. 8-10 are graphs illustrating the operation of the earlier series compensation system having a conventional thyristor switch, discussed in the background portion above. Detailed Description of a Preferred Embodiment
  • Fig. 1 illustrates a series compensation system or series compensator 20 constructed in accordance with the present invention for compensating a transmission line or power line 22 having a line current I L flowing therethrough.
  • the transmission line 22 has a first segment 24 coupling an AC power system or grid 25 with the series compensator 20.
  • the transmission line 22 has a second segment 26 which couples the series compensator 20 with a load 28.
  • the load 28 may have fluctuating power requirements on a seasonal, daily, or a substantially instantaneous basis.
  • the voltage at the load V L can drop under, that is, decrease to less than, acceptable minimum limits.
  • An undervoltage condition is caused essentially by the series inductance of the transmission line, and thus, the problem increases in severity as the length of the transmission line 22 increases. This undervoltage problem may severely limit the acceptable operating range of a practical long transmission line.
  • the series compensator 20 electrically inserts a capacitance in series with the transmission line to effectively cancel the series inductance during a heavy load period.
  • This series capacitance is provided by a capacitor bank 30, illustrated as having plural series connected capacitor bank sections 32, 34 and 36.
  • Each capacitor bank section 32, 34 and 36 has one or more discrete capacitors modules 38 coupled in parallel.
  • the number of parallel capacitors 38 within a capacitor bank section 32, 34 or 36 depends upon the current-carrying capacity required to handle the line current I L .
  • the number of capacitor bank sections 32, 34 or 36, or more, depends upon the required capacitance and series voltage drop across the capacitor bank 30.
  • the first capacitor bank section has a voltage drop V C1
  • the combined capacitor banks 34 and 36 have a total voltage drop V C2 .
  • the line current I L flows through the capacitor bank as indicated by the arrow labeled I c for capacitor current.
  • the line current is bypassed around the capacitor bank 30 as a bypass or switch current I s through the action of a turnoff switching device 40.
  • the turnoff switching device 40 has the ability to interrupt current, and insert the capacitor bank 30 in series with the transmission line 22, at any point during the waveform of the switch current I s .
  • the switching device comprises two turnoff switches 42 and 44.
  • the first switch 42 is in parallel with the capacitor bank section 32
  • the second switch 44 is in parallel with the two series connected capacitor bank sections 34 and 36.
  • Fig. 2 illustrates one embodiment of the turnoff switch 42 as having three series connected turnoff thyristor valves 45, 46 and 48.
  • Each thyristor valve, 45, 46 and 48 has two antiparallel turnoff thyristors 50 and 52, each having turnoff capability.
  • a controlled thyristor referred to herein as a "turnoff thyristor" has the ability to interrupt current at any point during the waveform of the switch current I s .
  • a turnoff thyristor such as thyristors 50 and 52, may be a gate turnoff (GTO) thyristor, a metal oxide semiconductor (MOS) controlled thyristor, or the like which are known to be structural equivalents thereto by those skilled in the art.
  • GTO gate turnoff
  • MOS metal oxide semiconductor
  • the turnoff thyristors receive an "on" command to enter a conducting state, and an "off” command to enter a nonconducting state via firing command signals 54 and 55 received by the respective thyristors 50 and 52, illustrated for the thyristor valve section 45.
  • the switch 42 may also include an overvoltage protection device, such as a gapless metal oxide arrestor 56, in parallel with the thyristors 50 and 52 of each valve 45, 46 and 48. Note, while only three thyristor valves are shown, the dashed lines between the valves 46 and 48 indicate that additional thyristor valves may be included to match the voltage drop V C1 of the capacitor bank section 32.
  • Fig. 3 shows an alternative to the Fig.
  • switch 42' has three or more turnoff thyristor valve sections 45, 46 and 48 as shown in Fig. 2.
  • the switch 42' rather than having separate overvoltage protection for each thyristor valve section, switch 42' has a single arrestor 58 coupled in parallel with the series combination of thyristor valves 45, 46 and 48. While Figs. 2 and 3 are illustrated for the switch 42, it is apparent that switch 44 may be similarly constructed. For example, if each of the capacitors 38 in Fig. 1 have the same voltage drop there across, then twice as many thyristor valves are required for switch 44 than for switch 42, assuming like-rated thyristors are used therein.
  • thyristor valve 60 which may be used instead of thyristor valves 45, 46 and 47.
  • the thyristor valve 60 includes two antiparallel coupled series branches 62 and 64, with each branch having a conventional thyristor 66 without gate turnoff capability, in series with a turnoff thyristor 68 having gate turnoff capability.
  • Several thyristor valves 60 may be coupled in series, as shown in for the thyristor valves 45, 46 and 48 in Figs. 2 and 3.
  • the thyristor valve 60 may have optional overvoltage protection, such as the gapless metal oxide arrestor 56 in parallel with one or more branches 62 and 64, similar to the embodiments of Figs. 2 or 3, respectively.
  • the series compensator 20 may also include a controller 70 for supplying firing commands signals 54, 55 and 54', 55' to the switches 42 and 44, respectively.
  • the controller 70 may receive a line status signal 72 from a line status monitoring sensor device 74.
  • the sensor 74 may be used to detect periods of normal and heavy loads. Although the sensor 74 is illustrated as measuring a load voltage V L , other power line parameters may be monitored to provide the line status signal 72, for instance, the line current I L . Instead of locating the sensor 74 in the transmission line segment 26, sensor 74 may be located in the transmission line segment 24, or at the load 28.
  • the controller 70 may receive a separate external command signal 76 from a system operator, or from some other higher-level controller (not shown) .
  • the controller 70 controls the switching device 40 to bypass the line current I s through a commutating path provided by the switches 42 and 44. That is, firing command signals 54, 55 and 54', 55' are provided to turn on the thyristors 50 and 52 to conduct the switch current I s therethrough.
  • the controller 70 responds to the line status signal by commanding the switching device 40 to be turned off so current is no longer bypassed around the capacitor bank 30.
  • the controller 70 may selectively either completely or partially insert the capacitor bank 30 in series with the transmission line 22 as needed to compensate the impedance of line 22.
  • both switches 42 and 44 are turned off. If only partial compensation is needed, only one of the switches 42 or 44 may be turned off, so the other switch remains conducting to bypass current around a portion of the capacitor bank 30.
  • By coupling the switches 42 and 44 to capacitor bank sections having different capacitances different levels of capacitance may be selectively inserted in the line 22 to compensate the line for corresponding different levels of load.
  • thyristors 50 and 52 the capacitor bank 30, or sections thereof, may be electrically inserted into the transmission line 22 at any time during the current cycle through the switching device 40.
  • Fig. 5 shows the line current I L , capacitor current I c , and capacitor voltage V C1 waveforms for inserting the single capacitor bank section 32 in series with the line by turning off switch 42.
  • the switch 42 is turned off at a peak in the line current cycle, as indicated the vertical dashed line connecting the three graphs of Fig. 5.
  • Such action would be virtually impossible for a conventional thyristor switch which is limited to interrupting current only at a natural current zero crossing.
  • the capacitors 38 of the capacitor bank section 32 are not subjected to the severe overvoltages experienced by capacitors in the earlier system having only a conventional thyristor switch.
  • the switch device 40 of the present invention there is no DC offset injected into the voltage waveform, and the DC component in the capacitor voltage is substantially eliminated.
  • the capacitor voltage stresses are advantageously reduced, and the capacitors 38 need not be designed to withstand double the rated voltage, as for capacitors used in the earlier compensation systems having conventional thyristor switches.
  • the series compensator 20 may be more economically constructed, as the capacitors require less material and physically consume less physical space.
  • switches 42 and 44 may be turned off one at a time to sequentially insert the capacitor bank sections in the line 22. For example, if initially switch 42 is open • and switch 44 is closed, the capacitor current I c will flow through only the first capacitor bank section 32, and then be bypassed through the second switch 44 as current I S2 . Since the thyristors 50 and 52 each have turnoff capability, switch 44 may be turned off at any time during the cycle of the switch current I S2 flowing therethrough.
  • the DC offset voltage for V C1 and V C2 waveforms is controlled so that it equals zero, and none of the capacitor bank sections 32, 34 or 36 see any overvoltage, such as that shown in Fig. 10 for the earlier system. Rather, the capacitor voltage waveforms for V C1 and V c2 are symmetrical, such as the waveform in the bottom graph of Fig. 5. Even if the capacitors within each capacitor bank section 32, 34 or 36 are unequal in size, no overvoltage is experienced. In this manner, operation of the series compensator 20 continues without the need for operation of the overvoltage protection, such as arrestors 56 or 58, or other overvoltage protection devices (not shown) coupled directly to the capacitor bank 30.
  • the overvoltage protection such as arrestors 56 or 58, or other overvoltage protection devices (not shown) coupled directly to the capacitor bank 30.
  • the capacitor bank voltage may be modulated as shown by the line current I L , capacitor current I c , capacitor voltage V C1 , and switch current I S1 waveforms in Fig. 7.
  • the switch current I S1 may be interrupted by turning switch 42 off at a controlled time ti before a current zero of the line current waveform.
  • the line current then flows through the capacitor bank section 32 until bypassed by turning on switch 42 when the voltage across the capacitor V C1 reaches zero again at a later time t 2 . That is, between t 0 and t lf t 2 and t 3 , and after time t.-, , current is bypassed around the capacitor bank section 32 and through the switch 42.
  • the modulation may be preformed with unequal pulses where one of the switching times t x or t 2 is closer to the current zero crossing than the other.
  • Such complex modulation schemes with unequal pulses may be useful in creating subsynchronous resonance (SSR) damping signals for damping undesirable subsynchronous resonance frequencies on the AC grid 25.
  • SSR subsynchronous resonance
  • FIG. 4 an operational advantage of mixing turnoff thyristors 68 with conventional thyristors 66 is illustrated.
  • An alternative method of operating the thyristor valve 60 is illustrated by assuming the valve 60 is coupled in parallel with the capacitor bank section 32, instead of switch 42.
  • commutation of the line current to capacitor bank section 32 begins by turning off the turnoff thyristors 68.
  • the balance of the capacitor voltage is taken up by turning on the conventional thyristors 66 after the switch current I s has reached a current zero. It is apparent to those skilled in the art that such a thyristor valve 60 may need careful matching of device characteristics and ⁇ mibber circuits (not shown) to be feasible.
  • the combined thyristor valve 60 may be more economically initially constructed, and more efficient in operation than the straight turnoff valves 45, 46 and 48.
  • the costs of the valves used in the switching device are dominant, and the ability to reduce the voltage seen by the valves, such as voltage V C1 across the bank section 32, results in a significant cost savings.
  • the capacitor bank 30 may also be more economically constructed. Different operation strategies also dictate the required rating of the series compensator 20.
  • the tradeoff involves either bypassing the capacitor bank 30 or inserting the capacitor bank 30 in series with the line. If the switching device 40 is conducting during a short circuit event, the thermal stresses on the power semiconductor devices 50 and 52, or 66 and 68, may be substantial. If the switches conduct during a system short circuit, there may be no need for the capacitor bank to have separate overvoltage protection, such as spark gaps, or metal oxide arrestors (not shown) . If during a short circuit event the switches 42 and 44 are not conducting, the voltage across the capacitor bank 30 may be substantial, even if the surge voltage is limited by spark gaps or metal oxide arrestors. Given the illustrated structure of the series compensator 20, both operating strategies are possible, that is, either letting short circuit current flow through the capacitor bank or through the switching device 40, and economic considerations will most likely determine which route is pursued.

Abstract

Un système de compensation série (20) est utilisé pour compenser une ligne de transmission (22) à travers laquelle passe un courant (IL) de ligne. Le système comprend un condensateur (30) devant être disposé en série dans la ligne de transmission (22), ainsi qu'un dispositif de commutation (40) de blocage parallèle au condensateur (30). En réponse à une commande de déclenchement (54, 55) provenant d'un contrôleur (70), soit le dispositif de commutation (40) conduit le courant de ligne (IL) de façon à le dévier par rapport au condensateur (30), soit ce dispositif est coupé à n'importe quel moment au cours du cycle de courant qui le traverse afin de connecter le condensateur (30) en série dans la ligne de transmission (22). Le dispositif de commutation (40) peut comprendre un thyristor blocable (GTO), un thyristor commandé par MOS, ou des combinaisons de ceux-ci avec des thyristors classiques. Un procédé également décrit, permet d'équilibrer une ligne de tansmission (22) au cours de périodes de charge importantes afin de prévenir des conditions de sous-tension inacceptables.
PCT/US1993/011509 1993-04-19 1993-11-29 Systeme de compensation serie commande par thyristor blocable WO1994024622A1 (fr)

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US4885793A 1993-04-19 1993-04-19
US048,857 1993-04-19

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Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
NL1000914C2 (nl) * 1995-08-01 1997-02-04 Geb Zuid Holland West Nv Werkwijze en inrichting voor continue instelling en regeling van een transformatoroverzetverhouding, alsmede transformator voorzien van een dergelijke inrichting.
EP0951126A1 (fr) * 1998-04-15 1999-10-20 Mitsubishi Electric Corporation Dispositif de compensation et système de transmission de puissance utilisant un dispositif de compensation
EP1252558A1 (fr) * 1999-12-28 2002-10-30 Ultrawatt.Com Systeme et procede de commande de tension
DE10119664A1 (de) * 2001-04-20 2002-11-14 Reinhausen Maschf Scheubeck Anordnung zur automatischen Spannungsregelung und Motorantrieb zur automatischen Spannungsregelung
WO2003103111A1 (fr) * 2002-05-31 2003-12-11 Bowman Power Systems Limited Generateur hautes frequences
GB2424772A (en) * 2005-04-02 2006-10-04 Paul Lenworth Mantock Power transmission system
CN102790387A (zh) * 2012-07-31 2012-11-21 许继集团有限公司 串联补偿中金属氧化物限压器的保护装置及串联补偿系统
EP2549614A1 (fr) * 2011-07-21 2013-01-23 Siemens Aktiengesellschaft Détermination de la part de courant continu dans un compensateur de puissance réactive contenant convertisseur mulit-niveau
WO2014067984A2 (fr) * 2012-11-02 2014-05-08 Bombardier Transportation Gmbh Agencement de circuit et procédé de fonctionnement d'un agencement de circuit
EP2751898A4 (fr) * 2011-08-30 2015-08-19 Cooper Technologies Co Commutateur de dérivation pour dispositif d'amplification
CN112688343A (zh) * 2021-03-22 2021-04-20 普世通（北京）电气有限公司 高压滤波暂态无功补偿装置

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US4999565A (en) * 1990-01-02 1991-03-12 Electric Power Research Institute Apparatus for controlling the reactive impedance of a transmission line
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US4292545A (en) * 1979-04-16 1981-09-29 Electric Power Research Institute, Inc. Method and means for damping subsynchronous oscillations and DC offset in an AC power system
US4829229A (en) * 1987-05-04 1989-05-09 Asea Brown Boveri Ab Series capacitor equipment
US4999565A (en) * 1990-01-02 1991-03-12 Electric Power Research Institute Apparatus for controlling the reactive impedance of a transmission line
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Cited By (21)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
NL1000914C2 (nl) * 1995-08-01 1997-02-04 Geb Zuid Holland West Nv Werkwijze en inrichting voor continue instelling en regeling van een transformatoroverzetverhouding, alsmede transformator voorzien van een dergelijke inrichting.
WO1997005536A1 (fr) * 1995-08-01 1997-02-13 N.V. Eneco Procede et dispositif de reglage et de regulation continus du rapport de spires d'un transformateur et transformateur pourvu d'un tel dispositif
US5969511A (en) * 1995-08-01 1999-10-19 N.V. Eneco Method and device for continuous adjustment and regulation of transformer turns ratio, and transformer provided with such device
EP0951126A1 (fr) * 1998-04-15 1999-10-20 Mitsubishi Electric Corporation Dispositif de compensation et système de transmission de puissance utilisant un dispositif de compensation
US6075349A (en) * 1998-04-15 2000-06-13 Mitsubishi Denki Kabushiki Kaisha Compensation device and power transmission system using a compensation device
EP1252558A1 (fr) * 1999-12-28 2002-10-30 Ultrawatt.Com Systeme et procede de commande de tension
EP1252558A4 (fr) * 1999-12-28 2003-03-26 Ultrawatt Com Systeme et procede de commande de tension
DE10119664A1 (de) * 2001-04-20 2002-11-14 Reinhausen Maschf Scheubeck Anordnung zur automatischen Spannungsregelung und Motorantrieb zur automatischen Spannungsregelung
US7215098B2 (en) 2002-05-31 2007-05-08 Bowman Power Systems Ltd. Electrical generating system having capacitative control of alternator regulation
WO2003103111A1 (fr) * 2002-05-31 2003-12-11 Bowman Power Systems Limited Generateur hautes frequences
GB2424772A (en) * 2005-04-02 2006-10-04 Paul Lenworth Mantock Power transmission system
EP2549614A1 (fr) * 2011-07-21 2013-01-23 Siemens Aktiengesellschaft Détermination de la part de courant continu dans un compensateur de puissance réactive contenant convertisseur mulit-niveau
EP2751898A4 (fr) * 2011-08-30 2015-08-19 Cooper Technologies Co Commutateur de dérivation pour dispositif d'amplification
US9444254B2 (en) 2011-08-30 2016-09-13 Cooper Technologies Company Bypass switch for a boost device
CN102790387A (zh) * 2012-07-31 2012-11-21 许继集团有限公司 串联补偿中金属氧化物限压器的保护装置及串联补偿系统
CN102790387B (zh) * 2012-07-31 2015-07-22 许继电气股份有限公司 串联补偿中金属氧化物限压器的保护装置及串联补偿系统
WO2014067984A2 (fr) * 2012-11-02 2014-05-08 Bombardier Transportation Gmbh Agencement de circuit et procédé de fonctionnement d'un agencement de circuit
WO2014067984A3 (fr) * 2012-11-02 2014-10-23 Bombardier Transportation Gmbh Agencement de circuit et procédé de fonctionnement d'un agencement de circuit
CN104736380A (zh) * 2012-11-02 2015-06-24 庞巴迪运输有限公司 包括拾取布置和可变补偿布置的电路布置及方法
US9809124B2 (en) 2012-11-02 2017-11-07 Bombardier Transportation Gmbh Circuit arrangement and method of operating a circuit arrangement
CN112688343A (zh) * 2021-03-22 2021-04-20 普世通（北京）电气有限公司 高压滤波暂态无功补偿装置

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