WO2016043508A1 - Appareil et procédé de coupure de courant continu - Google Patents

Appareil et procédé de coupure de courant continu Download PDF

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Publication number
WO2016043508A1
WO2016043508A1 PCT/KR2015/009685 KR2015009685W WO2016043508A1 WO 2016043508 A1 WO2016043508 A1 WO 2016043508A1 KR 2015009685 W KR2015009685 W KR 2015009685W WO 2016043508 A1 WO2016043508 A1 WO 2016043508A1
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WO
WIPO (PCT)
Prior art keywords
current
auxiliary
voltage
blocking
charging
Prior art date
Application number
PCT/KR2015/009685
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English (en)
Korean (ko)
Inventor
이우영
박상훈
송기동
장현재
정진교
Original Assignee
한국전기연구원
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Application filed by 한국전기연구원 filed Critical 한국전기연구원
Publication of WO2016043508A1 publication Critical patent/WO2016043508A1/fr

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    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
    • H02H3/00—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection
    • H02H3/08—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection responsive to excess current
    • H02H3/087—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection responsive to excess current for dc applications
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
    • H02H3/00—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection

Definitions

  • the present invention relates to a DC current blocking device and method, and more preferably, it is difficult to operate a high voltage DC current in a DC transmission system using a voltage converter that requires a significantly faster breaking time than a conventional current converter.
  • the present invention relates to a DC current blocking device and method that can be quickly cut off.
  • the use of semiconductor switching device may be a good alternative to perform the fast disconnection, but due to the high power loss and the economical difficulty according to the system configuration, the hybrid type blocking which uses a mechanical switch and a semiconductor switch together in recent years
  • the hybrid type blocking which uses a mechanical switch and a semiconductor switch together in recent years
  • the development trend of DC blocking technology for HVDC can be classified into two types. Firstly, DC current blocking is the responsibility of the semiconductor switch, and transient voltage applied after the blocking is the DC switch. There is a method that separates the required current and voltage characteristics from each other, and secondly, a mechanical circuit breaker is used. The manner in which the device is applied is suggested.
  • the present invention relates to the latter manner, which is known in the prior art relating to this manner, which is published in WO2013 / 045238 (Document 1).
  • a capacitor installed as a circuit breaker auxiliary device is always charged to artificially generate a current zero for DC current blocking.
  • the circuit breaker main elements connected to this capacitor also maintain the same voltage at all times, which is disadvantageous to the reliability of the lifetime due to voltage stress.
  • the main elements of the DC circuit breaker are installed at the point where high voltage is applied, but the voltage is not applied to the component itself. It is a method that should be used in a charged state, and it is required to solve the above problem.
  • the DC current interruption device and method are operated in a state in which the voltage is not applied at all times and the voltage is applied only when the circuit breaker operation is required. It is.
  • a DC current interruption device comprising: a main interrupter (10) configured in a form in which current limiting inductances (102, 104) are connected in series to a high speed mechanical switch (101, 103); A series connection part of an auxiliary interrupter 20 part and a reverse current conduction line part 30 and 60 installed on the circuit connected in parallel with the main interrupter part to be connected in parallel with the high speed mechanical switches 101 and 103; Auxiliary breaker 20 and the main breaker 20 is installed to be connected in parallel to the series connection of the high-speed mechanical switches (101, 103) and the current limiting inductance (102, 104) in parallel with the main breaker (10) A series connection part of the charging line parts 40 and 70; It characterized in that it comprises an auxiliary charging line unit 50 for connecting the connection point of the reverse current conducting line unit 30, 60 and the main charging line unit 40, 70 of the auxiliary blocking unit 20 with the ground side. Provide DC blocking device.
  • the auxiliary blocking unit 20 is characterized in that the charge voltage polarity inversion circuit in which the inductance 204 and the thyristor 205 is connected in series to the voltage charging capacitor 201 for generating a reverse current is connected in parallel It provides a DC circuit breaker.
  • auxiliary blocking unit 20 is connected to the surge arrester 207 in parallel with a series connection portion in which the voltage charging capacitor 201 and the reverse current adjusting resistor 202 for generating a reverse current is connected in series. It provides a DC circuit breaker.
  • the auxiliary blocking unit 20 provides a DC blocking device characterized in that the discharge resistor 209 for discharging the residual voltage of the capacitor 201 after the blocking operation is connected to the capacitor 201 in parallel.
  • the main charging line unit 40, 70 is composed of the diode 401, 701 and the charging resistors (402, 702) in series, through which the inductance (102, 104) and the high-speed mechanical switch (101, 103) It provides a DC blocking device, characterized in that the auxiliary breaker 20 is connected in parallel to the series connection of the).
  • the reverse current conducting line unit 30, 60 is composed of a thyristor (301, 601) through which the auxiliary breaker 20 is connected to the mechanical switch (101, 103) in parallel Provide a blocking device.
  • auxiliary charging line unit 50 is a mechanical switch 502 and the charging resistor 501 is connected in series, providing a DC current blocking device, characterized in that located between the auxiliary breaker 20 and the ground side. do.
  • DC circuit breaker characterized in that to connect the DC circuit breaker structure in a symmetrical form with respect to the auxiliary circuit breaker 20 for bidirectional current blocking.
  • the high speed mechanical switch (101, 103) and the current limiting inductance (102, 104) is formed in the form of a series connected in series;
  • Auxiliary breaker 20 and the main breaker 20 is installed to be connected in parallel to the series connection of the high-speed mechanical switches (101, 103) and the current limiting inductance (102, 104) in parallel with the main breaker (10)
  • the charging voltage of the capacitor 201 is reversed by the turn-on operation of the thyristor 205, and the thyristors 301 and 601 of the reverse current conducting line units 30 and 60 are inverted. It provides a direct current blocking method comprising the step of applying a reverse current to the high-speed mechanical switch (101, 103) through a turn-on operation of.
  • step b) when the current rise condition occurs due to the fault current, the capacitor 201 of the auxiliary breaker 20 is charged by the induced voltage generated in the current limiting inductances 102 and 104, or the normal state.
  • the DC current blocking condition occurs in the current state provides a DC current blocking method characterized in that the capacitor 201 of the auxiliary blocking unit 20 is charged through the auxiliary charging line 50.
  • the switch 502 in the case of charging the capacitor 201 of the auxiliary breaker 20 through the auxiliary charging line 50, after the switch 502 is charged to the line voltage and the load current is cut off the switch ( 502) provides a direct current blocking method characterized by a method of reducing the open state.
  • the voltage charging of the capacitor 201 is made by the voltage applied to the inductance 104 installed on the left side, and the main charging line part 70 installed in a symmetrical position with respect to the auxiliary breaker 20.
  • a direct current blocking method using a reverse current conducting line unit 60 to block direct current is also possible.
  • the capacitor was required to maintain the state of charge at all times by applying a blocking method that can separately deal with each case by applying the characteristics of the target breaking current, that is, the fault current and the load current. It can be charged only when the breaker operation is required to perform the blocking operation.
  • the DC current blocking device of the present invention can minimize the stress due to voltage applied to the circuit breaker components, and may have advantages in terms of breaker life and maintenance, and is a hybrid DC circuit breaker having high speed breaking characteristics. It can be usefully applied to HVDC transmission system operated by type converter.
  • FIG. 1 shows a circuit diagram constituting a one-way DC current breaker.
  • FIG. 2 shows a circuit diagram constituting a bidirectional DC current interruption device.
  • 5A shows the voltage value in the section showing the discharge of the capacitor 201.
  • FIG. 5B shows a voltage value at which a high voltage is applied to the capacitor polarity inversion and the fast switch 101 by the voltage V102 applied to the inductance 102.
  • 5C shows an enlarged view of section T A 2 and section T A 3 of FIG. 5B.
  • FIG. 5D is an enlarged view of FIG. 5B, which illustrates a current flowing through the thyristor 301 and a voltage generation time flowing through the high speed switch 101 according to sections t A 3 and t A 4.
  • FIG. 6A shows voltage and current values applied to respective components when the circuit in which the normal current is energized is cut off.
  • FIG. 6B shows the polarity inversion of the capacitor charged when the circuit in which the normal current is energized and the voltage value applied to the fast switch.
  • FIG. 6C shows an experimental value in which the transient voltage V101 is applied between the poles of the high speed mechanical switch after the arc arc extinguishes as a current zero is generated in the high speed mechanical switch by reverse current injection.
  • FIG. 6D shows a current flowing through the thyristor 301 and a voltage generation point flowing through the high speed switch 101.
  • the present invention relates to a DC current interruption device and method having a high-speed interruption function suitable for the protection of the HVDC transmission system employing a voltage converter system.
  • the present invention relates to a method of completing the blocking by generating a current zero in the blocking unit through reverse current injection, the conventional methods for this is to use the charging energy in the state that is always charged to the capacitor installed in the blocking unit
  • the breaker components are operated under voltage stress at all times.
  • a method of charging a capacitor only at the time of operation of the circuit breaker may be adopted, thereby reducing the existing voltage stress.
  • a method of charging a capacitor only at the time of operation of the circuit breaker may be adopted, thereby reducing the existing voltage stress.
  • an independent capacitor charging method to provide a technology that can perform the fault current as well as the load current blocking.
  • the main breaker 10 which is responsible for energizing current in a steady state is configured in a form in which the current limiting inductance 102 and the high speed mechanical switches 101 and 102 are connected in series. Then, the auxiliary breaker 20, the reverse current conduction line 30, and the main charging line 40 are connected to the main breaker 10 and the parallel circuit, and the auxiliary charge line 50 is connected in series with the main charger. Connect it to ground.
  • the auxiliary blocking unit 20 is a capacitor charging voltage polarity inversion circuit centering on the capacitor 201 and the inductance 204 and the thyristor 205 are connected in parallel with the capacitor 201 in series, and the capacitor 201
  • the surge arrester 207 is connected in parallel with the excitation capacitor 201 in order to limit the charging voltage of the voltage below a predetermined voltage. After the breaker operation ends, the remaining voltage of the capacitor 201 is discharged to initialize the breaker so that the discharge resistor 209 may be directly connected in parallel with the capacitor so that the discharge resistor 209 may be performed without an operation procedure for separate discharge.
  • the induced voltage is not generated in the current limiting inductance 102, and thus, the line grid voltage is used through the auxiliary charging line unit 50.
  • the capacitor 201 is charged.
  • the switch 502 is turned on to be made through the charging resistor 501.
  • the capacitor 201 charged according to each condition is then immediately reversed through the polarity inversion circuits 204 and 205, and the voltage polarity of the capacitor 201 is reversed.
  • the high speed mechanical switches 101 and 103 are applied to the high speed mechanical switches 101 and 103 according to the current direction in the opposite direction to the current to be cut off.
  • the polarity of all capacitors is inverted.
  • FIGS. 5 to 6 show voltage values and current values applied to the components with time, respectively, when the current zero point is formed.
  • the time point at which the reverse current is adjusted should be adjusted to maintain the inter-pole distance sufficient to withstand the transient voltage generated by the current interruption. That is, when the current energization through the high-speed mechanical switches (101, 103) is finished, the electrical energy accumulated in the DC line charges the capacitor 201 and excessive charging voltage is generated. When the voltage rises, it is limited through the surge arrester 207. That is, the line energy generated above a certain voltage is absorbed through the surge arrester 207, and the current decreases, and the breaking action is finally completed by the high speed mechanical switches 101 and 103 at the current zero point. When the current interruption is completed, the residual voltage present in the capacitor 201 is automatically discharged through the discharge resistor 209 and is ready for the next operation.
  • the auxiliary blocking unit 20 is installed in a symmetrical structure with respect to the embodiment of FIG. 1, which is intended to include a blocking characteristic for bidirectional current.
  • the inductance 104, reverse current conducting line portion 60, and main charging line portion 70 substitute for the functions of those having the same function, respectively, and the main interruption portion 10 also replaces the function of the symmetrical elements. do.
  • the fault current has a characteristic that the current magnitude increases with time and the load current maintains a constant current magnitude regardless of time. Seems. This means that in the case of load current interruption, the interruption characteristics do not depend on the time taken for interruption, but in case of fault current, the interruption must be made within a limited time (TB) from the time of the accident. If the interruption time passes a certain time after the accident occurs, the fault current increases and the interruption cannot be performed. Therefore, the current interruption time becomes an important factor in the occurrence of an accident current which is the object of the present invention. Therefore, the blocking time of FIG. 6A has a relatively long time compared to the blocking time of FIG. 5A. This is because the blocking must be performed within a limited time from the occurrence of the fault current.
  • a blocking condition according to an initial DC current input may be determined.
  • the DC current blocking condition may include an accident current generation condition and a DC current blocking signal input condition (S101).
  • the opening of the high speed switch is greater than or equal to a certain distance, the main interrupter through which the DC current is energized is opened. Therefore, the blocking of the current is completed through the DC current breaker (S105). After the blocking of the current is performed, the step of discharging the residual voltage of the capacitor is performed (S106), and preparation for charging according to the following operation is performed.
  • FIG. 5 shows the main voltage and current signal when the fault current blocking of the present invention.
  • t A 1 and t A 2 represent the charging section T A 1 of the capacitor 201 to allow the capacitor to be sufficiently charged during this period.
  • t A 1 represents the time of occurrence of an accident current and the time of loading and closing command.
  • Interval T A 2 is the timing of the polarity of the terminal voltage of the capacitor inverted by the polarity inverting circuit
  • the interval T A 3 is a section in which the transient voltage rises due to line stored energy in the capacitor T A 5 is the residual voltage of the capacitor Indicates the section that is automatically discharged.
  • FIG. 5A voltage values in a section indicating charge and discharge of the capacitor 201 are shown.
  • Figure 5b shows that the polarity is inverted in the charged capacitor to the voltage V A 201 is generated, and t 2 A time of the capacitor 201 by a voltage V 102 A applied to the inductance 102. The Thereafter, a high voltage is applied to the high speed switch 101.
  • FIG. 5C the section T A 2 and section T A 3 of FIG. 5B are enlarged.
  • FIG. 5D is an enlarged view of FIG. 5B, which illustrates a current flowing through the thyristor 301 and a voltage generation time flowing through the high speed switch 101 according to sections t A 3 and t A 4.
  • FIG. 5b shows that the polarity is inverted in the charged capacitor to the voltage V A 201 is generated, and t 2 A time of the capacitor 201 by a voltage V 102 A applied to the inductance 102. The Thereafter, a high voltage is applied to the high speed switch 101.
  • FIG. 5C the section T A 2 and section T A 3 of FIG. 5B are enlarged.
  • FIG. 5D is an enlarged view of FIG. 5B, which illustrates a current flowing through the thyristor 301 and a voltage generation time flowing through the high speed switch 101 according to sections t A 3 and t A 4.
  • Figure 6 shows the main voltage and current signal at the time of blocking the load current.
  • the voltage value in the section showing charge and discharge of the capacitor 201 is shown.
  • Figure 6a shows that the polarity is inverted in the charged capacitor to the voltage V B 201 is generated, and the time t B 2 of the capacitor 201 by a voltage V B 102 across the inductance (102). Thereafter, a high voltage is applied to the high speed switch 101.
  • FIG. 6C the 20ms to 21ms section of FIG. 6A is enlarged.
  • FIG. 6D is an enlarged view of FIG. 6A and shows a current flowing through the thyristor 301 and a voltage generation point flowing through the high speed switch 101.
  • a DC current blocking device and a method are described, but the scope of the technical idea of the present invention is not limited by the embodiments disclosed in the present invention, and each of the components constituting the DC current blocking device.
  • the form of the connection of these devices, or the way of constructing a circuit that performs the same function as each element or performs the same function should be interpreted as having a protection range for the same range and the equivalent range.

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  • Driving Mechanisms And Operating Circuits Of Arc-Extinguishing High-Tension Switches (AREA)

Abstract

La présente invention porte sur un appareil et un procédé de coupure de courant continu, et de préférence encore, sur un appareil et un procédé de coupure de courant continu qui peuvent couper rapidement un courant continu haute tension, sans difficultés de fonctionnement du système, dans un système de transmission de courant continu à l'aide d'un convertisseur de source de tension qui requiert un temps de coupure beaucoup plus court par comparaison à un système à convertisseur de source de courant classique, l'arc d'un interrupteur mécanique rapide pendant le temps de séparation des contacts étant supprimé par application d'un courant inverse à l'interrupteur mécanique rapide lorsqu'une condition de coupure de courant d'un système de transmission haute tension survient.
PCT/KR2015/009685 2014-09-18 2015-09-15 Appareil et procédé de coupure de courant continu WO2016043508A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
KR1020140124318A KR101641511B1 (ko) 2014-09-18 2014-09-18 직류전류 차단을 위한 장치 및 방법
KR10-2014-0124318 2014-09-18

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109888743A (zh) * 2019-02-28 2019-06-14 华北电力大学 一种适用于直流电网的降压钳位式直流断路器
JP2020502767A (ja) * 2016-12-21 2020-01-23 コリア エレクトロテクノロジー リサーチ インスティテュートKorea Electrotechnology Research Institute 真空ギャップスイッチを用いた逆電流注入型直流遮断装置及び方法

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KR101914053B1 (ko) 2016-12-02 2018-11-02 공주대학교 산학협력단 회로 차단기 및 회로 차단기의 게이트 구동 장치
KR101894973B1 (ko) 2016-12-02 2018-10-18 공주대학교 산학협력단 영전압-영전류 직류 회로 차단기
KR101943883B1 (ko) * 2016-12-30 2019-01-30 효성중공업 주식회사 절연형 양방향 ｄｃ-ｄｃ 컨버터의 스위칭 제어방법
KR102089141B1 (ko) * 2018-04-05 2020-03-13 한국전력공사 양방향 dc 전류 차단 장치
KR102090258B1 (ko) * 2018-11-22 2020-03-17 호남대학교 산학협력단 양방향 직류전원 차단 제어장치
WO2022114254A1 (fr) * 2020-11-25 2022-06-02 옵토파워주식회사 Disjoncteur bidirectionnel en courant continu
KR102386178B1 (ko) * 2021-06-30 2022-04-14 인텍전기전자주식회사 직류 차단 장치 및 그 이상 검출방법

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KR19990012163U (ko) * 1997-09-04 1999-04-06 김형벽 직류차단기 보호 시퀀스 회로
JP2011175925A (ja) * 2010-02-25 2011-09-08 Toshiba Corp 直流遮断器
WO2013071980A1 (fr) * 2011-11-18 2013-05-23 Abb Technology Ag Coupe-circuit hybride pour courant continu à haute tension, équipé d'un circuit d'amortissement
US20140078622A1 (en) * 2012-09-17 2014-03-20 Ge Energy Power Conversion Technology Ltd Circuit breakers
JP2014112984A (ja) * 2012-12-05 2014-06-19 Hitachi Ltd 直流送電制御システム。

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DE102011083693B3 (de) 2011-09-29 2013-03-28 Siemens Aktiengesellschaft Gleichspannungs-Leitungsschutzschalter
KR101483084B1 (ko) * 2013-01-24 2015-01-16 한국전기연구원 직류 전류 차단 장치 및 방법

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Publication number Priority date Publication date Assignee Title
KR19990012163U (ko) * 1997-09-04 1999-04-06 김형벽 직류차단기 보호 시퀀스 회로
JP2011175925A (ja) * 2010-02-25 2011-09-08 Toshiba Corp 直流遮断器
WO2013071980A1 (fr) * 2011-11-18 2013-05-23 Abb Technology Ag Coupe-circuit hybride pour courant continu à haute tension, équipé d'un circuit d'amortissement
US20140078622A1 (en) * 2012-09-17 2014-03-20 Ge Energy Power Conversion Technology Ltd Circuit breakers
JP2014112984A (ja) * 2012-12-05 2014-06-19 Hitachi Ltd 直流送電制御システム。

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2020502767A (ja) * 2016-12-21 2020-01-23 コリア エレクトロテクノロジー リサーチ インスティテュートKorea Electrotechnology Research Institute 真空ギャップスイッチを用いた逆電流注入型直流遮断装置及び方法
CN109888743A (zh) * 2019-02-28 2019-06-14 华北电力大学 一种适用于直流电网的降压钳位式直流断路器

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KR101641511B1 (ko) 2016-07-29

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