WO2017190608A1 - 一种电压源换流器的故障定位及恢复方法和系统 - Google Patents

一种电压源换流器的故障定位及恢复方法和系统 Download PDF

Info

Publication number
WO2017190608A1
WO2017190608A1 PCT/CN2017/081890 CN2017081890W WO2017190608A1 WO 2017190608 A1 WO2017190608 A1 WO 2017190608A1 CN 2017081890 W CN2017081890 W CN 2017081890W WO 2017190608 A1 WO2017190608 A1 WO 2017190608A1
Authority
WO
WIPO (PCT)
Prior art keywords
station
voltage
fault
faulty
converter
Prior art date
Application number
PCT/CN2017/081890
Other languages
English (en)
French (fr)
Inventor
李钢
卢宇
胡兆庆
田杰
董云龙
姜田贵
李海英
冯亚东
王柯
鲁江
随顺科
王辉
汪楠楠
Original Assignee
南京南瑞继保电气有限公司
南京南瑞继保工程技术有限公司
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 南京南瑞继保电气有限公司, 南京南瑞继保工程技术有限公司 filed Critical 南京南瑞继保电气有限公司
Priority to ES17792434T priority Critical patent/ES2847256T3/es
Priority to BR112018069099-6A priority patent/BR112018069099B1/pt
Priority to US16/098,878 priority patent/US10476261B2/en
Priority to EP19171554.9A priority patent/EP3537556B1/en
Priority to MX2018011338A priority patent/MX2018011338A/es
Priority to DK17792434.7T priority patent/DK3419138T3/da
Priority to RU2018135694A priority patent/RU2692674C1/ru
Priority to KR1020187027092A priority patent/KR102082597B1/ko
Priority to EP17792434.7A priority patent/EP3419138B1/en
Priority to CA3018404A priority patent/CA3018404C/en
Publication of WO2017190608A1 publication Critical patent/WO2017190608A1/zh

Links

Images

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
    • G01R31/40—Testing power supplies
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
    • G01R31/08—Locating faults in cables, transmission lines, or networks
    • 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
    • H02H3/02—Details
    • H02H3/06—Details with automatic reconnection
    • 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
    • H02H3/02—Details
    • H02H3/06—Details with automatic reconnection
    • H02H3/063—Details concerning the co-operation of many similar arrangements, e.g. in a network
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
    • H02H7/00—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions
    • H02H7/10—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions for converters; for rectifiers
    • H02H7/12—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions for converters; for rectifiers for static converters or rectifiers
    • H02H7/122—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions for converters; for rectifiers for static converters or rectifiers for inverters, i.e. dc/ac converters
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
    • H02H7/00—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions
    • H02H7/26—Sectionalised protection of cable or line systems, e.g. for disconnecting a section on which a short-circuit, earth fault, or arc discharge has occured
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
    • H02H7/00—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions
    • H02H7/26—Sectionalised protection of cable or line systems, e.g. for disconnecting a section on which a short-circuit, earth fault, or arc discharge has occured
    • H02H7/261—Sectionalised protection of cable or line systems, e.g. for disconnecting a section on which a short-circuit, earth fault, or arc discharge has occured involving signal transmission between at least two stations
    • H02H7/262—Sectionalised protection of cable or line systems, e.g. for disconnecting a section on which a short-circuit, earth fault, or arc discharge has occured involving signal transmission between at least two stations involving transmissions of switching or blocking orders
    • 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
    • H02J3/36—Arrangements for transfer of electric power between ac networks via a high-tension dc link
    • 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
    • Y02E40/10—Flexible AC transmission systems [FACTS]
    • 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
    • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • 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
    • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/60—Arrangements for transfer of electric power between AC networks or generators via a high voltage DC link [HVCD]

Definitions

  • the invention belongs to the field of direct current transmission, and particularly relates to a method and system for fault location and recovery of a voltage source converter.
  • the flexible AC-DC transmission technology adopts a voltage source converter, which can independently adjust the active power and reactive power, and the control is flexible and convenient; the receiving system can be a passive network, no external commutation voltage is needed; no reactive side is needed to provide reactive power Power can play the role of reactive power compensation, dynamically compensate AC bus reactive power, stabilize AC voltage, so it is one of the development directions of power system transmission.
  • the voltage source converter When the voltage source converter is connected to the AC grid using the transformerless mode as shown in FIG. 1, when the AC system is in an asymmetrical fault, the converter cannot isolate the unbalanced voltage generated by the AC system including the zero sequence voltage.
  • the MMC type voltage source converters such as the half bridge, the full bridge and the full bridge as shown in FIG. 2 have similar fault response characteristics. For example, when a single-phase ground fault occurs in a system that is not grounded, high-resistance grounded, or grounded via an arc-suppression coil, a zero-sequence voltage will appear in the AC grid voltage, causing an imbalance in the AC voltage at each station, and single-phase metality at the fault station.
  • the non-fault phase voltage rises from the phase voltage to the line voltage (phase voltage Times)
  • the zero-sequence voltage on the AC side enters the DC side through the inverter and causes the DC voltage to fluctuate.
  • the voltage fluctuation is transmitted to other converter stations via the DC cable or the overhead line, which will eventually cause the AC voltage of the non-fault station to also appear. Unbalanced, thus affecting the normal operation of the non-fault station AC system.
  • the current control detection method is to perform the negative sequence voltage in the unbalanced voltage. Control, the zero-sequence voltage in the unbalanced voltage is not detected and controlled, and for the unbalanced voltage with zero sequence, the same zero-sequence voltage is detected due to the fault, and how to accurately locate the fault is difficult.
  • the object of the present invention is to provide a fault location and recovery method and system for a voltage source converter, which detects that an AC voltage contains zero sequence voltage or DC contains an unbalanced voltage, locks the converter station, and blocks the converter station device. Continue to detect the zero-sequence voltage on the AC side of the converter station for fault location, and quickly recover the stations after fault location.
  • the fault location and recovery method is simple and practical, and has high reliability. It can effectively detect that the zero-sequence voltage on the AC side is transmitted to the opposite AC system through the voltage source converter, so that each station contains the AC-side zero-sequence voltage and is difficult to locate the fault.
  • the recovery method realizes that the non-faulty converter station is not affected by the faulty converter station and recovers quickly, and the fault of the faulty station and the non-fault station communication system is isolated.
  • the voltage source type converter station detects the AC side zero sequence voltage Uo_ac or the DC side unbalance voltage Uo_dc is greater than a set value Uo_set1 for more than a certain time ⁇ t1, latching the inverter, blocking During the detection of the AC side zero-sequence voltage Uo_ac of the converter station is greater than the set value Uo_set2 for more than a certain time ⁇ t2, the station is positioned as a faulty station, otherwise it is a non-faulty station.
  • the above-mentioned fault location method applied to the voltage source converter, the AC side zero sequence voltage Uo_ac calculation method is three-phase AC voltage addition and division, and then the band-pass filter takes the effective value, the DC side unbalanced voltage Uo_dc
  • the calculation method is that the positive and negative DC voltages are added and divided by the second passband filter to take the effective value.
  • the above-mentioned fault location method applied to the voltage source converter can block the converter stations at the same time, or can block the active power control converter station first, and detect the fault of the DC voltage control station and then block. DC voltage control station.
  • the above-mentioned fault location method applied to the voltage source converter can block the converter stations at the same time, and the zero-sequence voltage Uo_ac of the AC side is greater than or equal to the set value Uo_set2 during the blocking period, and is positioned as Fault station, otherwise it is a non-fault station.
  • the above-mentioned fault location method applied to the voltage source converter can also be used to lock the converter station in the active power control first, and the zero-sequence voltage on the AC side of each converter station in the active power control during the lockout period.
  • Uo_ac is greater than the set value Uo_set2 for more than a certain time ⁇ t2 to locate the fault active power control station, otherwise it is a non-fault active power control station.
  • the latching converter station is characterized in that the active power control station is blocked, and the zero-sequence voltage Uo_ac of the AC side of the DC voltage control station is greater than the set value Uo_set2 during the active power station latching period.
  • the fault station is a DC voltage station, and the converter station in DC voltage control needs to be further blocked.
  • the zero-sequence voltage Uo_ac of the AC side of the converter station under DC voltage control is greater than the set value Uo_set2 for more than a certain time ⁇ t2. For the fault DC voltage control station, otherwise it is a non-fault DC voltage control station.
  • the above-mentioned fault location method applied to the voltage source converter has a value range of 0.01 times AC rated voltage to 0.8 times rated AC voltage, and ⁇ t1 ranges from 0s to 6000s.
  • the above-mentioned fault location and recovery method applied to a voltage source converter has a value range of 0.01 times AC rated voltage to 0.8 times rated AC voltage, and ⁇ t2 ranges from 0s to 6000s.
  • the full bridge submodule adopts a full lock or a semi-latching manner to lock the inverter.
  • the above-mentioned fault location method applied to a voltage source converter is characterized in that the converter has a latching manner for the half-bridge sub-module topology structure to realize the converter station latching.
  • the above-mentioned fault location system applied to a voltage source converter comprises: a detection module, a blocking module, and a fault judgment positioning module.
  • the detecting module detects the AC side zero sequence voltage Uo_ac or the DC side unbalanced voltage Uo_dc is greater than the set value Uo_set1 for more than a certain time ⁇ t1, the latching module blocks the converter, and the fault judging positioning module detects the AC side zero sequence voltage Uo_ac is greater than the setting.
  • the fixed value Uo_set2 is positioned as a faulty station after a certain time ⁇ t2, otherwise it is a non-faulty station.
  • the Uo_ac calculation method is that the three-phase AC voltage is added and divided by three, and then the band-pass filter is used to take the effective value.
  • the DC side unbalanced voltage Uo_dc is calculated by adding the positive and negative DC voltages in addition to the two-pass bandpass filter. value.
  • the above-mentioned fault location system applied to the voltage source converter can block the converter stations at the same time, or can block the active power control converter station first, and determine whether to block the DC voltage control station according to the fault location.
  • the zero-sequence voltage Uo_ac of the AC side during the blocking period is greater than or equal to the set value Uo_set2 for more than a certain time ⁇ t2, and is positioned as a faulty station, otherwise Non-faulty station.
  • the above-mentioned fault location method applied to the voltage source converter first locks the converter station with active power control, and the fault judgment positioning module detects the zero-order voltage Uo_ac of the AC side of each converter station in the active power control is greater than the setting.
  • the fixed value Uo_set2 is positioned as a fault active power control station if it exceeds a certain time ⁇ t2, otherwise it is a non-fault active power control station.
  • the above-mentioned fault location system applied to the voltage source converter first locks the active power control station, and the fault judgment positioning module detects the AC side zero sequence voltage Uo_ac of the DC voltage control station is greater than the set value Uo_set2 when the active power station is locked. For a certain time ⁇ t2, the fault station is a DC voltage station, and the converter station in DC voltage control needs to be further blocked.
  • the zero-sequence voltage Uo_ac of the AC side of the converter station under DC voltage control is greater than the set value Uo_set2 for more than a certain time ⁇ t2. For the fault DC voltage control station, otherwise it is a non-fault DC voltage control station.
  • the above-mentioned fault location system applied to the voltage source converter has a value range of 0.01 times AC rated voltage to 0.8 times rated AC voltage, ⁇ t1 ranges from 0s to 6000s, and Uo_set2 ranges from 0.01 times AC.
  • the rated voltage is up to 0.8 times the rated AC voltage, and ⁇ t2 ranges from 0s to 6000s.
  • the above-mentioned fault locating system is applied to a voltage source converter.
  • the inverter is locked by a full lock or a semi-latching mode.
  • the converter is a half bridge sub-module topology structure using a latching mode to realize the converter station lock.
  • the invention also provides a fault recovery method applied to a voltage source converter.
  • the voltage source type converter station detects the AC side zero sequence voltage Uo_ac or the DC side unbalance voltage Uo_dc is greater than the set value Uo_set1 for more than a certain time ⁇ t1, and the lock is changed.
  • the zero-sequence voltage Uo_ac of each station on the AC side is greater than the set value Uo_set2 for more than a certain time ⁇ t2 to locate the faulty station, otherwise it is a non-faulty station.
  • the non-fault station After positioning to the faulty station The non-fault station resumes the unlocking operation, and the zero-sequence voltage Uo_ac of the AC side of the fault station is not greater than the set value Uo_set3. After the faulty station is unlocked for a certain period of time ⁇ t3, the faulty station is unlocked or the faulty station is directly restored to the unlocked operation after the zero-sequence voltage control is applied.
  • the AC side zero-sequence voltage Uo_ac calculation method is three-phase AC voltage addition and division, and then the band-pass filter takes the effective value, and the DC side unbalanced voltage Uo_dc is calculated.
  • the method is that the positive and negative DC voltages are added and divided by the second passband pass filter to take the effective value.
  • the above-mentioned fault recovery method applied to the voltage source converter detects that the zero-sequence voltage or the unbalanced voltage meets the requirements, and simultaneously locks each converter station, and the AC-side zero-sequence voltage Uo_ac is greater than or equal to the set value Uo_set2 during the blocking period. After a certain period of time ⁇ t2, it is positioned as a faulty station. Otherwise, it is a non-faulty station. After the faulty station is located, the non-faulty station resumes unlocking operation. The non-faulty station first restores the unlocking operation of the DC voltage control station, and resumes the unlocking operation after the active power control station. The faulty station detects that the AC side zero sequence voltage Uo_ac is not greater than the set value Uo_set3 for more than a certain time ⁇ t3 and resumes the faulty station unlocking operation.
  • the above-mentioned fault recovery method applied to the voltage source converter uses the simultaneous locking of each converter station, and the zero-sequence voltage Uo_ac of the AC side during the blocking period is greater than or equal to the set value Uo_set2 for more than a certain time ⁇ t2, and is positioned as a faulty station, otherwise Non-faulty station, after the faulty station is located, the non-fault station resumes unlocking operation.
  • the DC voltage control station in the non-fault station first resumes the unlocking operation, and the active power control station in the non-fault station resumes the unlocking operation, and the faulty station is put into zero-sequence voltage control recovery. Unlock the run.
  • the above-mentioned fault recovery method applied to the voltage source converter adopts a converter station that is first locked in active power control, and the zero-sequence voltage Uo_ac of the AC side of each converter station that is under active power control during the lockout is greater than the set value Uo_set2. After a certain time ⁇ t2, it is positioned as the fault active power control station; otherwise, it is a non-fault active power control station, and other non-fault active power stations resume unlocking operation.
  • the fault station active power converter station can choose to detect the AC side zero sequence voltage Uo_ac. If the fault value is greater than the set value Uo_set3 and the faulty station is unlocked after a certain time ⁇ t3, the zero sequence voltage control may be selected to directly resume the unlocking operation.
  • the above-mentioned fault recovery method applied to the voltage source converter adopts a latching active power control station.
  • the AC side zero sequence voltage Uo_ac of the DC voltage control station is greater than the set value Uo_set2 for more than a certain time ⁇ t2.
  • the fault station is a DC voltage station, and the converter station in DC voltage control needs to be further blocked.
  • the zero-sequence voltage Uo_ac of the AC side of the converter station under DC voltage control is greater than the set value Uo_set2 for more than a certain time ⁇ t2.
  • the zero-sequence voltage control can also be selected to directly resume the unlocking operation; if there is no fault DC outside the faulty DC voltage control station
  • the voltage control station can select the faulty station DC voltage control station to input zero-sequence voltage control to directly resume the unlocking operation, and then the active power station resumes the unlocking operation.
  • the active power control station can be converted into the DC voltage control station to unlock the operation first. After the active power control station is unlocked, the faulty DC voltage control station detects that the AC side zero sequence voltage Uo_ac is not greater than the set value Uo_set3 for more than a certain time ⁇ t3 to resume the faulty station unlocking operation.
  • the above-mentioned fault recovery method applied to the voltage source converter is performed by superimposing the zero-sequence voltage reference value Uoref generated by the zero-sequence voltage detection control on the original voltage reference wave Uref, and generating a new voltage reference wave Uref_new to input Zero sequence voltage control.
  • the above-mentioned fault recovery method applied to a voltage source converter calculates a zero-sequence voltage Uo_ac method according to an alternating current voltage, and adds three-phase alternating current voltages to divide by three, and calculates a zero-sequence voltage Uo_dc method according to a direct current voltage as a positive and negative voltage. Addition divided by two, Uoref selects Uo_ac or Uo_dc through the selector.
  • the above-mentioned fault recovery method applied to the voltage source converter has a value range of 0.01 times AC rated voltage to 0.8 times rated AC voltage, ⁇ t1 ranges from 0s to 6000s, and Uo_set2 ranges from 0.01 times AC.
  • the rated voltage is up to 0.8 times the rated AC voltage, ⁇ t2 ranges from 0s to 6000s; Uo_set3 ranges from 0.01 times AC rated voltage to 0.8 times rated AC voltage, and ⁇ t3 ranges from 0s to 6000s.
  • the converter uses a latching mode for the half-bridge sub-module topology to realize the lock-up of the converter station.
  • the invention provides a fault recovery method for a voltage source converter, and further provides a fault recovery system applied to a voltage source converter.
  • the voltage source converter station recovery system comprises a detection module, a blocking module and a fault judgment positioning module.
  • the fault recovery module detects that the AC side zero sequence voltage Uo_ac or the DC side unbalance voltage Uo_dc is greater than the set value Uo_set1 for more than a certain time ⁇ t1, the latching module locks the inverter, and the fault determination positioning module detects the AC side of each station during the blocking period.
  • the sequence voltage Uo_ac is greater than the set value Uo_set2 for more than a certain time ⁇ t2, it is positioned as a faulty station, otherwise it is a non-faulty station.
  • the fault recovery module resumes unlocking operation for the non-faulty station.
  • the zero-sequence voltage Uo_ac of the AC side of the faulty station is not greater than the set value Uo_set3.
  • the calculation method of the zero-sequence voltage Uo_ac of the detection module AC phase is that the three-phase AC voltage is added and divided by three, and the band-pass filter is used to take the effective value, and the DC side is unbalanced.
  • the voltage Uo_dc calculation method is that the positive and negative DC voltages are added and divided by the second passband filter to take the effective value.
  • the above-mentioned fault recovery system applied to a voltage source converter is characterized in that the blocking module simultaneously blocks each converter station, and the fault determination positioning module detects that the AC side zero sequence voltage Uo_ac is greater than or equal to the set value Uo_set2 for more than a certain period of time during the blocking period.
  • ⁇ t2 is positioned as a faulty station, otherwise it is a non-faulty station.
  • the fault recovery module resumes the non-faulty station and resumes the unlocking operation.
  • the DC voltage control station in the non-faulty station first resumes the unlocking operation, and the active power control station in the non-faulted station After the recovery is unlocked, the faulty station is put into zero-sequence voltage control to resume the unlocking operation.
  • the above-mentioned fault recovery system applied to a voltage source converter is characterized in that the blocking module blocks the converter station under the active power control, and the fault determination positioning module detects the AC side of each converter station in the active power control during the blocking period.
  • the sequence voltage Uo_ac is greater than the set value Uo_set2 for more than a certain time ⁇ t2, it is positioned as a fault active power control station; otherwise, it is a non-fault active power control station. After the faulty station is located, the fault recovery module recovers other non-fault active power stations to resume unlocking operation.
  • the station active power converter station can choose to detect that the AC side zero sequence voltage Uo_ac is not greater than the set value Uo_set3 after a certain time ⁇ t3 to recover the fault station unlock operation, or can choose to input the zero sequence voltage control to directly resume the unlock operation.
  • a certain time ⁇ t2 is positioned as a faulty station as a DC voltage station. After monitoring the faulty station as a DC voltage control station, it needs to further block the converter station in DC voltage control.
  • the fault judgment positioning module detects the AC side of the converter station under DC voltage control.
  • the zero sequence voltage Uo_ac is greater than the set value Uo_set2 for more than a certain time ⁇ t2 is the fault DC voltage control station, otherwise it is the non-fault DC voltage control station; if there is a non-fault DC voltage control station except the fault DC voltage control station, the fault recovery module recovers The non-fault DC voltage control station is unlocked and the active power station is unlocked.
  • the fault DC voltage control station can choose to detect that the AC side zero sequence voltage Uo_ac is not greater than the set value Uo_set3 and the fault station is unlocked after a certain time ⁇ t3.
  • Uo_ac is not greater than the set value Uo_set3 and the faulty station unlock operation is resumed after a certain time ⁇ t3.
  • the above-mentioned fault recovery system applied to the voltage source converter superimposes the zero-sequence voltage reference value Uoref generated by the zero-sequence voltage detection control on the original voltage reference wave Uref, and generates a new voltage reference wave Uref_new for control. .
  • the above-mentioned fault recovery system applied to the voltage source converter calculates the zero-sequence voltage Uo_ac method according to the alternating current voltage, and adds and divides the three-phase alternating current voltage to three, and calculates the zero-sequence voltage Uo_dc method according to the direct current voltage as the positive and negative voltages. Addition divided by two, Uoref selects Uo_ac or Uo_dc through the selector.
  • the above-mentioned fault recovery system applied to the voltage source converter has a value range of 0.01 times AC rated voltage to 0.8 times rated AC voltage, ⁇ t1 ranges from 0s to 6000s, and Uo_set2 ranges from 0.01 times AC.
  • the rated voltage is up to 0.8 times the rated AC voltage, ⁇ t2 ranges from 0s to 6000s; Uo_set3 ranges from 0.01 times AC rated voltage to 0.8 times rated AC voltage, and ⁇ t3 ranges from 0s to 6000s.
  • the above-mentioned fault recovery system applied to a voltage source converter is characterized in that when the converter is a full bridge submodule or a full bridge submodule topology, the full lock or semi-latching manner is used to lock the inverter. .
  • the above-mentioned fault recovery system applied to a voltage source converter is characterized in that the converter has a latching manner for the half-bridge sub-module topology to realize the lock-up of the converter station.
  • the fault location method is simple and practical, and has high reliability. It can effectively detect the zero-sequence voltage of the AC side and conduct it to the opposite AC system through the voltage source converter so that each station contains the AC-side zero-sequence voltage and is difficult to locate the fault.
  • the non-faulty converter station is quickly recovered by the recovery method, and the fault of the faulty station and the non-fault station communication system is isolated.
  • the fault recovery method provided at the same time can also ensure continuous operation during the faulty station failure.
  • Figure 1 is a schematic diagram of the faulty station and non-faulty voltage when the faulty station sends a k1, k2 point single-phase earth fault when the two-terminal converter is connected by transformerless DC.
  • Figure 2 is a schematic diagram of the voltage of the faulty station and the non-fault station after the faulty station is blocked or the zero-sequence voltage is controlled when the faulty station is sent with k1, k2 when the two-terminal converter is connected by transformerless DC.
  • bridge arm module may be a half bridge (HBSM), a full bridge (FBSM) or a full bridge like (SFBSM).
  • FIG. 4 is a diagram of a fault continuation recovery operation control architecture with superimposed zero sequence voltage control.
  • FIG. 5 is a waveform diagram of the fault simulation during the continuous unlocking operation when the station 1 and the station 2 do not adopt the superimposed zero-sequence voltage control in the case of the k2 single-phase ground fault in FIG. 1 .
  • the invention provides a fault location and recovery method applied to a voltage source converter, which can effectively detect that the zero-sequence voltage on the AC side is transmitted to the opposite AC system through the voltage source converter, so that each station has an AC-side zero-sequence voltage. Fault location problem, through the fault recovery method, the non-faulty converter station is not affected by the faulty converter station and recovers quickly, and the fault of the fault station and the non-fault station AC system is isolated.
  • the fault recovery method provided at the same time can also ensure continuous operation during the faulty station failure.
  • FIG. 1 shows the schematic diagram of flexible DC transmission at both ends.
  • the flexible DC transmission system at both ends is taken as an example to illustrate the same. It is also applicable to the DC transmission and distribution network.
  • the flexible DC transmission adopts transformerless connection, and the AC system is the arc suppression coil grounding system.
  • the station 1 has a C phase fault, and the station 1 non-fault phase voltage rises before the fault. Times, the phase of the cut changes, the zero-sequence voltage is contained in the three phases, and the AC voltage of the station 2 also contains the zero-sequence voltage.
  • the waveform diagram of the station 2 is as shown in Fig. 1, and the station 2 is shown.
  • Fig. 5 The left side of Fig. 5 is the fault three-phase AC voltage diagram, and the right side is the non-fault station AC voltage diagram. How to accurately locate the communication system failure of the station in two stations or multiple stations is difficult.
  • the voltage source type converter station detects the AC side zero sequence voltage Uo_ac or the DC side unbalanced voltage Uo_dc is greater than the set value Uo_set1 for more than a certain time ⁇ t1, latches the inverter, and detects the commutation station AC side zero sequence during the lockout period.
  • the voltage Uo_ac is greater than the set value Uo_set2 for more than a certain time ⁇ t2
  • the station is located as a faulty station, otherwise it is a non-faulty station.
  • Figure 2 is a schematic diagram of the waveforms when all the two stations are locked or the active power control station of the two stations is locked. It is known from the figure that after the blocking, the non-fault station 2 has no zero-sequence AC voltage, and the two stations can be accurately positioned after blocking. Fault station.
  • the AC side zero-sequence voltage Uo_ac is calculated by adding the three-phase AC voltage and dividing it to three. After the bandpass filtering, the RMS value is taken.
  • the DC side unbalanced voltage Uo_dc is calculated by adding the positive and negative DC voltages to the second passband. After filtering, take the effective value.
  • the latching converter can block each converter station at the same time, or the active power control converter station can be blocked first, and the DC voltage control station is blocked after detecting the fault of the DC voltage control station.
  • the AC side zero sequence voltage Uo_ac during the blocking period is greater than or equal to the set value Uo_set2 for more than a certain time ⁇ t2 to locate the faulty station, otherwise it is a non-faulty station.
  • the zero-sequence voltage Uo_ac of the AC side of each converter station during the lockout period is greater than the set value Uo_set2 for more than a certain time ⁇ t2, then the fault is the active power control station; otherwise It is a non-fault active power control station; during the active power station blocking, the AC side zero-sequence voltage Uo_ac of the DC voltage control station is greater than the set value Uo_set2 for more than a certain time ⁇ t2, then the faulty station is a DC voltage station, and further blocking is required for DC voltage control.
  • the converter station detects that the zero-sequence voltage Uo_ac of the AC side of the converter station under DC voltage control is greater than the set value Uo_set2 for more than a certain time ⁇ t2, which is a fault DC voltage control station, otherwise it is a non-fault DC voltage control station.
  • Uo_set1 is 0.01 times AC rated voltage to 0.8 times rated AC voltage
  • ⁇ t1 ranges from 0s to 6000s
  • Uo_set2 ranges from 0.01 times AC rated voltage to 0.8 times
  • the rated AC voltage, ⁇ t2 ranges from 0s to 6000s.
  • the converter is a half-bridge sub-module topology adopting a blocking mode to realize the converter station blocking, and the half-bridge topology blocking sub-module conduction state table is shown in Table 1;
  • the specific implementation manner of the fault location system applied to the voltage source converter is that the voltage source type converter station fault location system comprises: a detection module, a blocking module, and a fault judgment positioning module.
  • the detecting module detects the AC side zero sequence voltage Uo_ac or the DC side unbalanced voltage Uo_dc is greater than the set value Uo_set1 for more than a certain time ⁇ t1, the latching module blocks the converter, and the fault judging positioning module detects the AC side zero sequence voltage Uo_ac is greater than the setting.
  • the fixed value Uo_set2 is positioned as a faulty station after a certain time ⁇ t2, otherwise it is a non-faulty station.
  • the calculation method of the AC-side zero-sequence voltage Uo_ac in the detection module of the positioning system is that the three-phase AC voltage is added and divided by three, and then the band-pass filter is used to take the effective value.
  • the DC-side unbalanced voltage Uo_dc is calculated by adding the positive and negative DC voltages. Take the rms value after the second pass band pass filter.
  • the blocking module can block each converter station at the same time, or can block the active power control converter station first, and decide whether to block the DC voltage control station according to the fault location.
  • the zero-order voltage Uo_ac of the AC side during blocking is greater than or equal to the set value Uo_set2 for more than a certain time ⁇ t2, then it is positioned as a fault station, otherwise it is a non-fault station, the waveform diagram is shown in Figure 2;
  • the fault judgment positioning module detects that the zero-sequence voltage Uo_ac of the AC side of each converter station in the active power control is greater than the set value Uo_set2 and is positioned as a fault for more than a certain time ⁇ t2 Active power control station, otherwise it is non-faulty Rate control station.
  • the fault judgment positioning module detects the DC voltage control station AC side zero sequence voltage Uo_ac is greater than the set value Uo_set2 for more than a certain time ⁇ t2, then the fault station is a DC voltage station, and further needs to block the DC voltage control converter station.
  • detecting the zero-sequence voltage Uo_ac of the AC side of the converter station in DC voltage control is greater than the set value Uo_set2 for more than a certain time ⁇ t2 is the fault DC voltage control station, otherwise it is the non-fault DC voltage control station.
  • the above-mentioned fault location system applied to the voltage source converter has a value range of 0.01 times AC rated voltage to 0.8 times rated AC voltage, ⁇ t1 ranges from 0s to 6000s, and Uo_set2 ranges from 0.01 times AC.
  • the rated voltage is up to 0.8 times the rated AC voltage, and ⁇ t2 ranges from 0s to 6000s.
  • the above-mentioned fault locating system is applied to a voltage source converter.
  • the converter is a full bridge sub-module and a full-bridge sub-module topology
  • the full bridge, the full-bridge module and the clamped dual sub-module are fully used.
  • Blocking or semi-latching mode blocking converter, the full-bridge and full-bridge semi-blocking sub-module conduction state is shown in Table 2 and Table 3.
  • the clamped double sub-module conduction state is shown in Table 4; the inverter is half
  • the topology of the bridge module adopts the blocking mode to realize the blocking of the converter station.
  • the conduction state table of the half-bridge topology blocking sub-module is shown in Table 1.
  • the voltage source converter station detects the AC side zero sequence voltage Uo_ac or the DC side unbalance voltage Uo_dc is greater than the set value Uo_set1 for more than a certain time ⁇ t1.
  • the blocking converter is locked during the blocking period.
  • the zero-sequence voltage Uo_ac of each station on the AC side is greater than the set value Uo_set2 for more than a certain time ⁇ t2 to locate the faulty station, otherwise it is a non-faulty station. After the faulty station is located, the non-fault station resumes the unlocking operation.
  • the zero-sequence voltage Uo_ac of the AC side of the faulty station is not greater than the set value Uo_set3.
  • the method for calculating the AC-side zero-sequence voltage Uo_ac in the fault recovery method applied to the voltage source converter is that the three-phase AC voltage is added and divided by three, and then the band-pass filter is used to take the effective value, and the DC side unbalanced voltage Uo_dc is calculated as positive.
  • the negative DC voltage is added and divided by the second passband filter to take the effective value.
  • the converter stations are blocked at the same time, and the zero-order voltage Uo_ac of the AC side is greater than or equal to the set value Uo_set2 for more than a certain time ⁇ t2 during the blocking period. Then it is positioned as a faulty station, otherwise it is a non-faulty station. After the faulty station is located, the non-faulty station resumes unlocking operation. The non-faulty station first restores the unlocking operation of the DC voltage control station, and the active power control station resumes the unlocking operation. The faulty station detects The AC side zero sequence voltage Uo_ac is not greater than the set value Uo_set3 and the faulty station unlock operation is resumed after a certain time ⁇ t3.
  • a fault recovery method applied to a voltage source converter adopts simultaneous blocking of each converter station, and the zero-sequence voltage Uo_ac of the AC side is greater than or equal to the set value Uo_set2 during the latching period, and is positioned as a faulty station for more than a certain time ⁇ t2, otherwise it is a non-faulty station.
  • the non-fault station resumes the unlocking operation.
  • the DC voltage control station in the non-fault station first resumes the unlocking operation, and the active power control station in the non-fault station resumes the unlocking operation, and the faulty station inputs zero-sequence voltage control to resume the unlocking operation.
  • a fault recovery method applied to a voltage source converter adopts a converter station that is first locked in active power control, and the zero-sequence voltage Uo_ac of the AC side of each converter station that is under active power control during the lockout is greater than a set value Uo_set2 for more than a certain time.
  • ⁇ t2 is positioned as the fault active power control station, otherwise it is the non-fault active power control station, and other non-fault active power stations resume unlocking operation.
  • the fault station active power converter station can choose to detect the AC side zero sequence voltage Uo_ac is not greater than the setting. After the value Uo_set3 exceeds the certain time ⁇ t3, the faulty station is unlocked and the faulty station is unlocked. Alternatively, the zero-sequence voltage control can be selected to directly resume the unlocking operation.
  • the AC voltage zero-order voltage Uo_ac of the DC voltage control station is greater than the set value Uo_set2 for more than a certain time ⁇ t2, and the faulty station is a DC voltage station, and the converter station in the DC voltage control needs to be further blocked, and the detection is performed.
  • the zero-sequence voltage Uo_ac of the AC side of the converter station under DC voltage control is greater than the set value Uo_set2 for a certain period of time ⁇ t2 is the fault DC voltage control station, otherwise it is a non-fault DC voltage control station; if there is any fault other than the fault DC voltage control station The fault DC voltage control station unlocks the non-fault DC voltage control station, and then the active power station resumes unlocking operation.
  • the fault DC voltage control station can choose to detect that the AC side zero sequence voltage Uo_ac is not greater than the set value Uo_set3 for more than a certain time ⁇ t3 After the recovery of the faulty station is unlocked, the zero-sequence voltage control can be selected to directly resume the unlocking operation; if there is no non-faulty DC voltage control station outside the faulty DC voltage control station, the DC voltage control station of the faulty station can be selected to directly restore the zero-sequence voltage control.
  • the unlocking operation can also be selected to convert an active power control station into a DC voltage control station to unlock the operation first, and the remaining active power control stations are unlocked and the faulty DC voltage control station detects that the AC side zero sequence voltage Uo_ac is not greater than the set value.
  • Uo_set3 resumes the faulty station unlocking operation after a certain time ⁇ t3.
  • the fault recovery method applied to the voltage source converter generates a voltage reference wave Uref based on the positive and negative sequence control by superimposing the zero sequence voltage reference value Uoref generated by the zero sequence voltage detection control on the outer loop power control and the inner loop current control.
  • a new voltage reference wave Uref_new is generated to input zero sequence voltage control.
  • the three-phase AC voltage is added and divided by three.
  • the zero-sequence voltage Uo_dc is calculated according to the DC voltage.
  • the positive and negative voltages are added and divided by two.
  • Uoref selects Uo_ac or Uo_dc through the selector.
  • the detailed control block diagram is shown in Figure 4.
  • each fault setting value ranges as follows: Uo_set1 ranges from 0.01 times AC rated voltage to 0.8 times rated AC voltage, and ⁇ t1 ranges from 0s to 6000s; Uo_set2 ranges from 0.01 times AC rated voltage to 0.8 times rated AC voltage, ⁇ t2 ranges from 0s to 6000s; Uo_set3 ranges from 0.01 times AC rated voltage to 0.8 times rated AC voltage, ⁇ t3 The range is from 0s to 6000s.
  • a fault recovery method applied to a voltage source converter wherein the full bridge, the full bridge module, and the clamped double submodule are fully latched or the full bridge submodule and the clamped dual submodule are fully latched or
  • the semi-latching mode blocking converter, the full-bridge and full-bridge semi-locking sub-module conduction states are shown in Table 2 and Table 3:
  • the converter uses the blocking mode to realize the blocking of the converter station for the half-bridge sub-module topology.
  • the conduction state table of the half-bridge topology blocking sub-module is shown in Table 1:
  • a fault recovery system for a voltage source converter is provided, and the voltage source type converter station recovery system includes a detection module, a blocking module, and a fault judgment. Positioning module, fault recovery module, detection module detects AC side zero sequence voltage Uo_ac or straight The flow side unbalanced voltage Uo_dc is greater than the set value Uo_set1 for more than a certain time ⁇ t1, the blocking module locks the inverter, and the fault determination positioning module detects that the AC side zero sequence voltage Uo_ac of each station is greater than the set value Uo_set2 for more than a certain time ⁇ t2 to be positioned as Fault station, otherwise it is a non-fault station.
  • the fault recovery module resumes unlocking operation for the non-faulty station.
  • the zero-sequence voltage Uo_ac of the AC side of the faulty station is not greater than the set value Uo_set3.
  • the faulty station is unlocked or the faulty station is put into zero-sequence voltage control. Resume the unlock run.
  • a fault recovery system for a voltage source converter is used to calculate the AC side zero-sequence voltage Uo_ac of the detection module.
  • the three-phase AC voltage is added and divided by three, and the band-pass filter is used to take the effective value, and the DC side unbalanced voltage Uo_dc
  • the calculation method is that the positive and negative DC voltages are added and divided by the second passband filter to take the effective value.
  • a fault recovery system applied to a voltage source converter can block each converter station at the same time.
  • the fault judgment positioning module detects that the AC side zero sequence voltage Uo_ac is greater than or equal to the set value Uo_set2 for more than a certain time ⁇ t2. Fault station, otherwise it is a non-fault station. After the faulty station is located, the fault recovery module recovers the non-fault station to resume unlocking operation. The non-fault station first restores the unlocking operation of the DC voltage control station, and resumes the unlocking operation after the active power control station.
  • the faulty station can It is detected that the AC-side zero-sequence voltage Uo_ac is not greater than the set value Uo_set3 and the faulty station is unlocked after a certain time ⁇ t3; or the faulty station is put into the zero-sequence voltage control to resume the unlocking operation.
  • a fault recovery system applied to a voltage source converter locks a converter station in active power control, and the fault determination positioning module detects the zero-order voltage Uo_ac of the AC side of each converter station under active power control.
  • the fixed value Uo_set2 is positioned as the fault active power control station after a certain time ⁇ t2, otherwise it is the non-fault active power control station.
  • the fault recovery module recovers other non-fault active power stations to resume the unlock operation, and the fault station active power commutation
  • the station can choose to detect that the AC side zero sequence voltage Uo_ac is not greater than the set value Uo_set3 and the faulty station unlock operation is resumed after a certain time ⁇ t3, or the zero sequence voltage control can be selected to directly resume the unlock operation.
  • a further fault recovery system applied to a voltage source converter the blocking module blocks the active power control station, and the fault determination positioning module detects the AC side zero sequence voltage Uo_ac of the DC voltage control station is greater than the set value Uo_set2 during the active power station lockout period.
  • a certain time ⁇ t2 is positioned as a faulty station as a DC voltage station. After monitoring the faulty station as a DC voltage control station, it needs to further block the converter station in DC voltage control.
  • the fault judgment positioning module detects the AC side of the converter station under DC voltage control.
  • the zero sequence voltage Uo_ac is greater than the set value Uo_set2 for a certain time ⁇ t2 is the fault DC voltage control station, otherwise it is a non-fault DC voltage control station; if there is a non-fault DC voltage control station except the fault DC voltage control station, the fault recovery module After recovery, the non-fault DC voltage control station is unlocked, and then the active power station is unlocked.
  • the fault DC voltage control station can choose to detect that the AC side zero sequence voltage Uo_ac is not greater than the set value Uo_set3 and the fault station is unlocked after a certain time ⁇ t3.
  • Uo_ac is not greater than the set value Uo_set3 and the faulty station unlock operation is resumed after a certain time ⁇ t3.
  • a fault recovery system applied to a voltage source converter superimposing a zero-sequence voltage reference value Uoref generated by zero-sequence voltage detection control on an outer loop power control and an inner loop current control to generate a voltage reference wave Uref based on positive and negative sequence control
  • a new voltage reference wave Uref_new is generated to input the zero sequence voltage control.
  • the three-phase AC voltage is added and divided by three.
  • the zero-sequence voltage Uo_dc is calculated according to the DC voltage.
  • the positive and negative voltages are added and divided by two.
  • Uoref selects Uo_ac or Uo_dc through the selector.
  • the detailed control block diagram is shown in Figure 4.
  • each set value ranges from: Uo_set1 ranges from 0.01 times AC rated voltage to 0.8 times rated AC voltage, and ⁇ t1 ranges from 0s Up to 6000s; Uo_set2 ranges from 0.01 times AC rated voltage to 0.8 times rated AC voltage, ⁇ t2 ranges from 0s to 6000s; Uo_set3 ranges from 0.01 times AC rated voltage to 0.8 times rated AC voltage, ⁇ t3 value range It is from 0s to 6000s.
  • the fault location method can also be integrated according to the needs, and each converter station can be blocked for detection to realize the detection and location of the AC fault. After the fault is located, the fault can be superimposed and the zero sequence voltage control can be used. The fault station non-fault stations are superimposed with zero-sequence voltage control to resume operation, but they are all within the research method of this scheme.
  • the present embodiment is directed to a flexible DC transmission at both ends as an example.
  • the present invention is applicable to a flexible AC/DC transmission system composed of two or more voltage source type converter stations, for example, two ends/ Multi-terminal flexible DC transmission, DC distribution network, unified power flow controller (UPFC), etc.
  • UPFC unified power flow controller
  • the embodiment is described by taking a full bridge, a full bridge, a clamped double submodule and a half bridge as an example, but the solution is applicable to both ends and multi-end systems composed of any voltage source converter, such as a multi-inverter topology. , X-MMC sub-module topology and so on.

Landscapes

  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Inverter Devices (AREA)
  • Rectifiers (AREA)
  • Direct Current Feeding And Distribution (AREA)
  • Locating Faults (AREA)

Abstract

本发明涉及一种应用于电压源换流器的故障定位及恢复方法和系统，检测到交流电压含有零序电压或直流含有不平衡电压，闭锁换流站，通过继续检测换流器交流侧零序电压进行故障定位，故障定位后恢复各站运行。此故障定位及恢复方法简单实用、可靠性高，能够有效检测交流侧零序电压通过电压源换流器传导到对侧交流系统使各站均含有交流侧零序电压难于故障定位问题，同时通过恢复方法实现非故障换流站不受故障换流站影响快速，实现了基于电压源换离站系统的快速恢复，能够推动无变压器接线方式在电压源换流器中的应用，最终实现换流站占地空间减少、损耗降低和造价减少。

Description

一种电压源换流器的故障定位及恢复方法和系统 技术领域
本发明属于直流输电领域，特别涉及一种电压源换流器故障定位及恢复方法和系统。
背景技术
柔性交直流输电技术采用电压源型换流器，可以独立调节有功功率和无功功率，控制灵活方便；受端系统可以为无源网络，不需要外加换相电压；不需要交流侧提供无功功率且能够起到无功补偿的作用，动态补偿交流母线无功功率，稳定交流电压，因此是电力系统传输的发展方向之一。
基于模块化多电平技术(MMC)的电压源型换流器的发展，解决了基于两电平技术的均压问题和损耗大问题，同时降低了交流系统谐波，使电压源型换流器采用无变压器方式接入交流电网成为一种可能，从而降低换流站总体投资、占地空间和功率损耗。
当电压源型换流器采用如图1所示的无变压器方式接入交流电网时，当交流系统发生不对称故障时，换流器无法隔离交流系统产生的包含零序电压的不平衡电压，对于如图2所示的半桥、全桥和类全桥等MMC型电压源换流器均具有相似的故障响应特性。例如在不接地、高阻接地或经消弧线圈接地的系统发生单相接地故障时，交流电网电压中将出现零序电压，并引起各站交流电压出现不平衡，故障站发生单相金属性接地时非故障相电压从相电压升高为线电压(相电压的
Figure PCTCN2017081890-appb-000001
倍)，交流侧的零序电压经过换流器进入直流侧并引起直流电压出现波动，该电压波动经直流电缆或架空线路传导至其他换流站，最终将导致非故障站的交流电压也出现不平衡，从而影响非故障站交流系统的正常运行。
由于在有变压器接入方式下零序电压可以被变压器隔离在交流侧，不会通过直流侧传导到其它换流站交流侧，因此目前的控制检测方法是对不平衡电压中的负序电压进行控制，对不平衡电压中的零序电压是不进行检测和控制的，而且对于含有零序的不平衡电压，因故障均检测出相同的零序电压，如何准确定位故障是其难点。Song Hong-Seok等人的“Dual current control scheme for PWM converter under unbalance input voltage conditions”(IEEE Transcation on  IndustialElectronics.1999，46(5)：953-959)针对不对称故障，分别进行负序电压前馈和双序电流内环控制，但只能抑制负序电流。陈海荣博士论文“交流系统故障时VSC-HVDC系统的控制与保护策略研究”对正负序不对称故障进行了详细的推导，在采用双序电流环的基础上，负序电流的参考值又分为抑制交流侧负序和抑制直流侧二倍频，但这两个目标不能同时实现。以上推导计算均只针对负序进行控制，而对于本站故障时零序电压通过换流站传导到其它换流站如何检测定位故障站，定位后如何快速恢复系统运行未有提及。
对于无变压器接入方式下含零序电压的不平衡电压在电压源型换流站之间的传播，因各站均能检测到含零序电压的不平衡电压，如何准确故障定位成了其中的难点，影响了采用无变压器接入方式柔性交直流输电系统的应用和推广。因此，有必要寻找一种无变压器方式下换流站交流系统故障准确定位及恢复方法，从而推动采用无变压器方式下或变压器二次侧高阻接地电压源换利器应用，最终实现减少换流站占地、损耗及造价。
发明内容
本发明的目的是提供一种应用于电压源换流器的故障定位及恢复方法和系统，检测到交流电压含有零序电压或直流含有不平衡电压，闭锁换流站，通过闭锁换流站器件继续检测换流站交流侧零序电压大小进行故障定位，故障定位后快速恢复各站运行。此故障定位及恢复方法简单实用、可靠性高，能够有效检测交流侧零序电压通过电压源换流器传导到对侧交流系统使各站均含有交流侧零序电压难于故障定位问题，同时通过恢复方法实现非故障换流站不受故障换流站影响快速恢复，实现了故障站与非故障站交流系统故障的隔离。
为了达成上述目的，本发明采用的技术方案是：
一种应用于电压源换流器的故障定位方法，电压源型换流站检测交流侧零序电压Uo_ac或者直流侧不平衡电压Uo_dc大于设定值Uo_set1超过一定时间Δt1，闭锁换流器，闭锁期间检测换流站交流侧零序电压Uo_ac大于设定值Uo_set2超过一定时间Δt2则定位该站为故障站，否则为非故障站。
上述的一种应用于电压源换流器的故障定位方法，交流侧零序电压Uo_ac计算方法为三相交流电压相加除于三后经带通滤波后取有效值，直流侧不平衡电压Uo_dc计算方法为正负极直流电压相加除于二经带通滤波后取有效值。
上述的一种应用于电压源换流器的故障定位方法，闭锁换流器可以同时闭锁各换流站，也可以先闭锁有功功率控制换流站，检测出为直流电压控制站故障后再闭锁直流电压控制站。
上述的一种应用于电压源换流器的故障定位方法，闭锁换流站可以采用同时闭锁各换流站，闭锁期间交流侧零序电压Uo_ac大于等于设定值Uo_set2超过一定时间Δt2则定位为故障站，否则为非故障站。
上述的一种应用于电压源换流器的故障定位方法，闭锁换流站也可采用先闭锁处于有功功率控制的换流站，闭锁期间处于有功功率控制的各换流站交流侧零序电压Uo_ac大于设定值Uo_set2超过一定时间Δt2则定位为故障有功功率控制站，否则为非故障有功功率控制站。
上述的一种应用于电压源换流器的故障定位方法，闭锁换流站其特征在于闭锁有功功率控制站，有功功率站闭锁期间直流电压控制站交流侧零序电压Uo_ac大于设定值Uo_set2超过一定时间Δt2则定位为故障站为直流电压站，需要进一步闭锁处于直流电压控制的换流站，检测处于直流电压控制的换流站交流侧零序电压Uo_ac大于设定值Uo_set2超过一定时间Δt2则为故障直流电压控制站，否则为非故障直流电压控制站。
上述的一种应用于电压源换流器的故障定位方法，Uo_set1取值范围为0.01倍交流额定电压至0.8倍额定交流电压，Δt1取值范围为0s至6000s。
上述的一种应用于电压源换流器的故障定位及恢复方法，Uo_set2取值范围为0.01倍交流额定电压至0.8倍额定交流电压，Δt2取值范围为0s至6000s。
上述的一种应用于电压源换流器的故障定位方法，换流器为包含全桥子模块或类全桥子模块拓扑结构时，全桥子模块采用全闭锁或者半闭锁方式闭锁换流器。
上述的一种应用于电压源换流器的故障定位方法，其特征在于，换流器为半桥子模块拓扑结构采用闭锁方式实现换流站闭锁。
上述的一种应用于电压源换流器的故障定位系统，电压源型换流站故障定位系统包含：检测模块、闭锁模块、故障判断定位模块。检测模块检测交流侧零序电压Uo_ac或者直流侧不平衡电压Uo_dc大于设定值Uo_set1超过一定时间Δt1，闭锁模块闭锁换流器，闭锁期间故障判断定位模块检测各站交流侧零序电压Uo_ac大于设定值Uo_set2超过一定时间Δt2则定位为故障站，否则为非故障站。
上述的一种应用于电压源换流器的故障定位系统，检测模块中交流侧零序电 压Uo_ac计算方法为三相交流电压相加除于三后经带通滤波后取有效值，直流侧不平衡电压Uo_dc计算方法为正负极直流电压相加除于二经带通滤波后取有效值。
上述的一种应用于电压源换流器的故障定位系统，闭锁模块可以同时闭锁各换流站，也可以先闭锁有功功率控制换流站，根据故障定位情况决定是否闭锁直流电压控制站。
上述的一种应用于电压源换流器的故障定位系统，同时闭锁各换流站时，闭锁期间交流侧零序电压Uo_ac大于等于设定值Uo_set2超过一定时间Δt2则定位为故障站，否则为非故障站。
上述的一种应用于电压源换流器的故障定位方法，先闭锁有功功率控制的换流站，闭锁期间故障判断定位模块检测处于有功功率控制的各换流站交流侧零序电压Uo_ac大于设定值Uo_set2超过一定时间Δt2则定位为故障有功功率控制站，否则为非故障有功功率控制站。
上述的一种应用于电压源换流器的故障定位系统，先闭锁有功功率控制站时，有功功率站闭锁期间故障判断定位模块检测直流电压控制站交流侧零序电压Uo_ac大于设定值Uo_set2超过一定时间Δt2则定位为故障站为直流电压站，需要进一步闭锁处于直流电压控制的换流站，检测处于直流电压控制的换流站交流侧零序电压Uo_ac大于设定值Uo_set2超过一定时间Δt2则为故障直流电压控制站，否则为非故障直流电压控制站。
上述的一种应用于电压源换流器的故障定位系统，Uo_set1取值范围为0.01倍交流额定电压至0.8倍额定交流电压，Δt1取值范围为0s至6000s；Uo_set2取值范围为0.01倍交流额定电压至0.8倍额定交流电压，Δt2取值范围为0s至6000s。
上述的一种应用于电压源换流器的故障定位系统，换流器为包含全桥子模块或类似全桥子模块拓扑结构时，采用全闭锁或者半闭锁方式闭锁换流器。
上述的一种应用于电压源换流器的故障定位系统，换流器为半桥子模块拓扑结构采用闭锁方式实现换流站闭锁。
本发明还提供一种应用于电压源换流器的故障恢复方法，电压源型换流站检测交流侧零序电压Uo_ac或者直流侧不平衡电压Uo_dc大于设定值Uo_set1超过一定时间Δt1，闭锁换流器，闭锁期间各站交流侧零序电压Uo_ac大于设定值Uo_set2超过一定时间Δt2则定位为故障站，否则为非故障站。定位到故障站后 非故障站恢复解锁运行，故障站交流侧零序电压Uo_ac不大于设定值Uo_set3超过一定时间Δt3后恢复故障站解锁运行或故障站投入零序电压控制后直接恢复解锁运行。
上述一种应用于电压源换流器的故障恢复方法，交流侧零序电压Uo_ac计算方法为三相交流电压相加除于三后经带通滤波后取有效值，直流侧不平衡电压Uo_dc计算方法为正负极直流电压相加除于二经带通滤波后取有效值。
上述的一种应用于电压源换流器的故障恢复方法，检测到零序电压或不平衡电压满足要求后，同时闭锁各换流站，闭锁期间交流侧零序电压Uo_ac大于等于设定值Uo_set2超过一定时间Δt2则定位为故障站，否则为非故障站，定位出故障站后非故障站恢复解锁运行，非故障站首先直流电压控制站先恢复解锁运行，有功功率控制站后恢复解锁运行，故障站检测到交流侧零序电压Uo_ac不大于设定值Uo_set3超过一定时间Δt3后恢复故障站解锁运行。
上述的一种应用于电压源换流器的故障恢复方法，采用同时闭锁各换流站，闭锁期间交流侧零序电压Uo_ac大于等于设定值Uo_set2超过一定时间Δt2则定位为故障站，否则为非故障站，定位出故障站后非故障站恢复解锁运行，非故障站中直流电压控制站先恢复解锁运行，非故障站中有功功率控制站后恢复解锁运行，故障站投入零序电压控制恢复解锁运行。
上述的一种应用于电压源换流器的故障恢复方法，采用先闭锁处于有功功率控制的换流站，闭锁期间处于有功功率控制的各换流站交流侧零序电压Uo_ac大于设定值Uo_set2超过一定时间Δt2则定位为故障有功功率控制站，否则为非故障有功功率控制站，其它非故障有功功率站恢复解锁运行，故障站有功功率换流站可以选择检测到交流侧零序电压Uo_ac不大于设定值Uo_set3超过一定时间Δt3后恢复故障站解锁运行，也可以选择投入零序电压控制直接恢复解锁运行。
上述的一种应用于电压源换流器的故障恢复方法，采用闭锁有功功率控制站，有功功率站闭锁期间直流电压控制站交流侧零序电压Uo_ac大于设定值Uo_set2超过一定时间Δt2则定位为故障站为直流电压站，需要进一步闭锁处于直流电压控制的换流站，检测处于直流电压控制的换流站交流侧零序电压Uo_ac大于设定值Uo_set2超过一定时间Δt2则为故障直流电压控制站，否则为非故障直流电压控制站；除故障直流电压控制站外如有非故障直流电压控制站，则非故障直流电压控制站解锁运行，然后有功功率站恢复解锁运行，故障站直流电压控制站可以 选择检测到交流侧零序电压Uo_ac不大于设定值Uo_set3超过一定时间Δt3后恢复故障站解锁运行，也可以选择投入零序电压控制直接恢复解锁运行；除故障直流电压控制站外如无非故障直流电压控制站，可以选择故障站直流电压控制站投入零序电压控制直接恢复解锁运行，然后有功功率站恢复解锁运行，也可选择将某有功功率控制站转换为直流电压控制站先解锁运行，其余有功功率控制站后解锁运行，故障站直流电压控制站检测到交流侧零序电压Uo_ac不大于设定值Uo_set3超过一定时间Δt3后恢复故障站解锁运行。
上述的一种应用于电压源换流器的故障恢复方法，通过将零序电压检测控制生成的零序电压参考值Uoref叠加在原有的电压参考波Uref上，生成新的电压参考波Uref_new来投入零序电压控制。
上述的一种应用于电压源换流器的故障恢复方法，根据交流电压计算零序电压Uo_ac方法为三相交流电压相加除于三，根据直流电压计算零序电压Uo_dc方法为正负极电压相加除于二，Uoref通过选择器选择Uo_ac或Uo_dc。
上述的一种应用于电压源换流器的故障恢复方法，Uo_set1取值范围为0.01倍交流额定电压至0.8倍额定交流电压，Δt1取值范围为0s至6000s；Uo_set2取值范围为0.01倍交流额定电压至0.8倍额定交流电压，Δt2取值范围为0s至6000s；Uo_set3取值范围为0.01倍交流额定电压至0.8倍额定交流电压，Δt3取值范围为0s至6000s。
上述的一种应用于电压源换流器的故障恢复方法，换流器为包含全桥子模块或类似全桥子模块拓扑结构时，采用全闭锁或者半闭锁方式闭锁换流器。
上述的一种应用于电压源换流器的故障恢复方法，换流器为半桥子模块拓扑结构采用闭锁方式实现换流站闭锁。
本发明提供一种电压源换流器的故障恢复方法外还提供一种应用于电压源换流器的故障恢复系统，电压源型换流站恢复系统包含检测模块、闭锁模块、故障判断定位模块、故障恢复模块，检测模块检测交流侧零序电压Uo_ac或者直流侧不平衡电压Uo_dc大于设定值Uo_set1超过一定时间Δt1，闭锁模块闭锁换流器，闭锁期间故障判断定位模块检测各站交流侧零序电压Uo_ac大于设定值Uo_set2超过一定时间Δt2则定位为故障站，否则为非故障站。定位到故障站后故障恢复模块对非故障站恢复解锁运行，故障站交流侧零序电压Uo_ac不大于设定值Uo_set3超过一定时间Δt3后恢复故障站解锁运行或故障站投入零序电压控制后 直接恢复解锁运行。
上述的一种应用于电压源换流器的故障恢复系统，检测模块交流侧零序电压Uo_ac计算方法为三相交流电压相加除于三后经带通滤波后取有效值，直流侧不平衡电压Uo_dc计算方法为正负极直流电压相加除于二经带通滤波后取有效值。
上述的一种应用于电压源换流器的故障恢复系统，闭锁模块同时闭锁各换流站，闭锁期间故障判断定位模块检测交流侧零序电压Uo_ac大于等于设定值Uo_set2超过一定时间Δt2则定位为故障站，否则为非故障站，定位出故障站后故障恢复模块恢复非故障站恢复解锁运行，非故障站首先直流电压控制站先恢复解锁运行，有功功率控制站后恢复解锁运行，故障站检测到交流侧零序电压Uo_ac不大于设定值Uo_set3超过一定时间Δt3后恢复故障站解锁运行。
上述的一种应用于电压源换流器的故障恢复系统，其特征在于闭锁模块同时闭锁各换流站，闭锁期间故障判断定位模块检测交流侧零序电压Uo_ac大于等于设定值Uo_set2超过一定时间Δt2则定位为故障站，否则为非故障站，定位出故障站后故障恢复模块恢复非故障站恢复解锁运行，非故障站中直流电压控制站先恢复解锁运行，非故障站中有功功率控制站后恢复解锁运行，故障站投入零序电压控制恢复解锁运行。
上述的一种应用于电压源换流器的故障恢复系统，其特征在于闭锁模块闭锁处于有功功率控制的换流站，闭锁期间故障判断定位模块检测处于有功功率控制的各换流站交流侧零序电压Uo_ac大于设定值Uo_set2超过一定时间Δt2则定位为故障有功功率控制站，否则为非故障有功功率控制站，定位出故障站后故障恢复模块恢复其它非故障有功功率站恢复解锁运行，故障站有功功率换流站可以选择检测到交流侧零序电压Uo_ac不大于设定值Uo_set3超过一定时间Δt3后恢复故障站解锁运行，也可以选择投入零序电压控制直接恢复解锁运行。
上述的一种应用于电压源换流器的故障恢复系统，闭锁模块闭锁有功功率控制站，有功功率站闭锁期间故障判断定位模块检测直流电压控制站交流侧零序电压Uo_ac大于设定值Uo_set2超过一定时间Δt2则定位为故障站为直流电压站，监测到故障站为直流电压控制站后需要进一步闭锁处于直流电压控制的换流站，故障判断定位模块检测处于直流电压控制的换流站交流侧零序电压Uo_ac大于设定值Uo_set2超过一定时间Δt2则为故障直流电压控制站，否则为非故障直流电压控制站；除故障直流电压控制站外如有非故障直流电压控制站，故障恢复模块恢 复则非故障直流电压控制站解锁运行，然后恢复有功功率站解锁运行，故障站直流电压控制站可以选择检测到交流侧零序电压Uo_ac不大于设定值Uo_set3超过一定时间Δt3后恢复故障站解锁运行，也可以选择投入零序电压控制直接恢复解锁运行；除故障直流电压控制站外如无非故障直流电压控制站，故障恢复模块可以选择故障站直流电压控制站投入零序电压控制直接恢复解锁运行，然后有功功率站恢复解锁运行，也可选择将某有功功率控制站转换为直流电压控制站先解锁运行，其余有功功率控制站后解锁运行，故障站直流电压控制站检测到交流侧零序电压Uo_ac不大于设定值Uo_set3超过一定时间Δt3后恢复故障站解锁运行。
上述的一种应用于电压源换流器的故障恢复系统，将零序电压检测控制生成的零序电压参考值Uoref叠加在原有的电压参考波Uref上，生成新的电压参考波Uref_new来进行控制。
上述的一种应用于电压源换流器的故障恢复系统，根据交流电压计算零序电压Uo_ac方法为三相交流电压相加除于三，根据直流电压计算零序电压Uo_dc方法为正负极电压相加除于二，Uoref通过选择器选择Uo_ac或Uo_dc。
上述的一种应用于电压源换流器的故障恢复系统，Uo_set1取值范围为0.01倍交流额定电压至0.8倍额定交流电压，Δt1取值范围为0s至6000s；Uo_set2取值范围为0.01倍交流额定电压至0.8倍额定交流电压，Δt2取值范围为0s至6000s；Uo_set3取值范围为0.01倍交流额定电压至0.8倍额定交流电压，Δt3取值范围为0s至6000s。
上述的一种应用于电压源换流器的故障恢复系统，其特征在于，换流器为包含全桥子模块或类似全桥子模块拓扑结构时，采用全闭锁或者半闭锁方式闭锁换流器。
上述的一种应用于电压源换流器的故障恢复系统，其特征在于，换流器为半桥子模块拓扑结构采用闭锁方式实现换流站闭锁。
采用上述方案后，本发明的有益效果为：
(1)故障定位方法简单实用、可靠性高，能够有效检测交流侧零序电压通过电压源换流器传导到对侧交流系统使各站均含有交流侧零序电压难于故障定位问题。
(2)该故障定位方法判定位出故障侧后，通过恢复方法实现非故障换流站不受故障换流站影响快速恢复，实现了故障站与非故障站交流系统故障的隔离。 同时提供的故障恢复方法还能够保障故障站故障期间投入持续运行。
(3)采用该故障定位与恢复方法后，能够推动无变压器接线方式在电压源换流器中的应用，实现减少占地空间、降低损耗和降低造价的目的。
附图说明
图1是两端换流器采用无变压器直流方式连接时，故障站发送k1，k2点单相接地故障时故障站和非故障的电压示意图。
图2是两端换流器采用无变压器直流方式连接时，故障站发送k1，k2时故障时故障站闭锁或投入零序电压控制后，故障站与非故障站电压示意图。
图3是本发明中换流器的拓扑，其中桥臂模块可以是半桥(HBSM)，全桥(FBSM)或者类全桥(SFBSM)。
图4是叠加零序电压控制的故障继续恢复运行控制架构图。
图5是图1中k2单相接地故障时，站1与站2不采取叠加零序电压控制时持续解锁运行时故障仿真波形图。
具体实施方式
以下将结合附图及具体实施例，对本发明的技术方案进行详细说明。
本发明提供一种应用于电压源换流器的故障定位及恢复方法，能够有效检测交流侧零序电压通过电压源换流器传导到对侧交流系统使各站均含有交流侧零序电压难于故障定位问题，通过故障恢复方法实现非故障换流站不受故障换流站影响快速恢复，实现了故障站与非故障站交流系统故障的隔离。同时提供的故障恢复方法还能够保障故障站故障期间投入持续运行。
图1两端柔性直流输电示意图，以两端柔性直流输电系统为例进行说明，同样适用于直流输配电网。柔性直流输电采用无变压器连接，且交流系统为经消弧线圈接地系统，站1发生C相故障，站1非故障相电压升高到故障前
Figure PCTCN2017081890-appb-000002
倍，切相位发生变化，三相中含有零序电压，站2交流电压也含有零序电压，站1与站2交流电压初始相位完全一致时，站2波形示意图如图1所示，站2也感应到零序电压，三相电压出现不平衡。仿真实际情况下故障站站1与非故障站站2波形如图5所示，图5左边为故障三相交流电压图，右边为非故障站交流电压图。如何准确定位两站或多站中那个站发生交流系统故障是其难点。为了准确定位故障，电压源型换流站检测交流侧零序电压Uo_ac或者直流侧不平衡电压Uo_dc大于设 定值Uo_set1超过一定时间Δt1，闭锁换流器，闭锁期间检测换流站交流侧零序电压Uo_ac大于设定值Uo_set2超过一定时间Δt2则定位该站为故障站，否则为非故障站。图2为闭锁两站全部闭锁或者两站中任一有功功率控制站闭锁时波形示意图，由图知，闭锁后非故障站站2无零序交流电压，通过闭锁后两站不同特性可以准确定位故障站。
交流侧零序电压Uo_ac计算方法为三相交流电压相加除于三后经带通滤波后取有效值，直流侧不平衡电压Uo_dc计算方法为正负极直流电压相加除于二经带通滤波后取有效值。
进一步的，图2中闭锁换流器可以同时闭锁各换流站，也可以先闭锁有功功率控制换流站，检测出为直流电压控制站故障后再闭锁直流电压控制站。
同时闭锁期间，闭锁期间交流侧零序电压Uo_ac大于等于设定值Uo_set2超过一定时间Δt2则定位为故障站，否则为非故障站。
采用先先闭锁处于有功功率控制的换流站时，闭锁期间处于有功功率控制的各换流站交流侧零序电压Uo_ac大于设定值Uo_set2超过一定时间Δt2则定位为故障有功功率控制站，否则为非故障有功功率控制站；有功功率站闭锁期间直流电压控制站交流侧零序电压Uo_ac大于设定值Uo_set2超过一定时间Δt2则定位为故障站为直流电压站，需要进一步闭锁处于直流电压控制的换流站，检测处于直流电压控制的换流站交流侧零序电压Uo_ac大于设定值Uo_set2超过一定时间Δt2则为故障直流电压控制站，否则为非故障直流电压控制站。
进一地，各定值取值范围为Uo_set1取值范围为0.01倍交流额定电压至0.8倍额定交流电压，Δt1取值范围为0s至6000s；Uo_set2取值范围为0.01倍交流额定电压至0.8倍额定交流电压，Δt2取值范围为0s至6000s。
电压源换流器的故障定位方法，换流器为包含全桥子模块、类全桥子模块拓扑结构时，全桥子、类全桥模块和钳位双子模块采用全闭锁或者半闭锁方式闭锁换流器，类全桥和全桥半闭锁子模块导通状态如表2和表3所示：
表2类全桥子模块工作状态
Figure PCTCN2017081890-appb-000003
表3全桥子模块工作状态
Figure PCTCN2017081890-appb-000004
Figure PCTCN2017081890-appb-000005
钳位双子模块导通状态如表4所示：
表4钳位双子模块工作状态
Figure PCTCN2017081890-appb-000006
换流器为半桥子模块拓扑结构采用闭锁方式实现换流站闭锁，半桥拓扑结构闭锁子模块导通状态表如表1所示；
表1半桥子模块工作状态
Figure PCTCN2017081890-appb-000007
本发明应用于电压源换流器的故障定位系统具体实现方式为，电压源型换流站故障定位系统包含：检测模块、闭锁模块、故障判断定位模块。检测模块检测交流侧零序电压Uo_ac或者直流侧不平衡电压Uo_dc大于设定值Uo_set1超过一定时间Δt1，闭锁模块闭锁换流器，闭锁期间故障判断定位模块检测各站交流侧零序电压Uo_ac大于设定值Uo_set2超过一定时间Δt2则定位为故障站，否则为非故障站。
定位系统中检测模块中交流侧零序电压Uo_ac计算方法为三相交流电压相加除于三后经带通滤波后取有效值，直流侧不平衡电压Uo_dc计算方法为正负极直流电压相加除于二经带通滤波后取有效值。
闭锁模块可以同时闭锁各换流站，也可以先闭锁有功功率控制换流站，根据故障定位情况决定是否闭锁直流电压控制站。
故障定位系统闭锁所有换流站时，闭锁期间交流侧零序电压Uo_ac大于等于设定值Uo_set2超过一定时间Δt2则定位为故障站，否则为非故障站，波形示意图如图2所示；
故障定位系统采用先闭锁有功功率控制的换流站时，闭锁期间故障判断定位模块检测处于有功功率控制的各换流站交流侧零序电压Uo_ac大于设定值Uo_set2超过一定时间Δt2则定位为故障有功功率控制站，否则为非故障有功功 率控制站。有功功率站闭锁期间故障判断定位模块检测直流电压控制站交流侧零序电压Uo_ac大于设定值Uo_set2超过一定时间Δt2则定位为故障站为直流电压站，需要进一步闭锁处于直流电压控制的换流站，检测处于直流电压控制的换流站交流侧零序电压Uo_ac大于设定值Uo_set2超过一定时间Δt2则为故障直流电压控制站，否则为非故障直流电压控制站。
上述的一种应用于电压源换流器的故障定位系统，Uo_set1取值范围为0.01倍交流额定电压至0.8倍额定交流电压，Δt1取值范围为0s至6000s；Uo_set2取值范围为0.01倍交流额定电压至0.8倍额定交流电压，Δt2取值范围为0s至6000s。
上述的一种应用于电压源换流器的故障定位系统，换流器为包含全桥子模块、类全桥子模块拓扑结构时，全桥子、类全桥模块和钳位双子模块采用全闭锁或者半闭锁方式闭锁换流器，类全桥和全桥半闭锁子模块导通状态如表2和表3所示，钳位双子模块导通状态如表4所示；换流器为半桥子模块拓扑结构采用闭锁方式实现换流站闭锁，半桥拓扑结构闭锁子模块导通状态表如表1所示。
在故障定位基础上，研究一种应用于电压源换流器的故障恢复方法，电压源型换流站检测交流侧零序电压Uo_ac或者直流侧不平衡电压Uo_dc大于设定值Uo_set1超过一定时间Δt1，闭锁换流器，闭锁期间各站交流侧零序电压Uo_ac大于设定值Uo_set2超过一定时间Δt2则定位为故障站，否则为非故障站。定位到故障站后非故障站恢复解锁运行，故障站交流侧零序电压Uo_ac不大于设定值Uo_set3超过一定时间Δt3后恢复故障站解锁运行或故障站投入零序电压控制后直接恢复解锁运行。
应用于电压源换流器的故障恢复方法中交流侧零序电压Uo_ac计算方法为三相交流电压相加除于三后经带通滤波后取有效值，直流侧不平衡电压Uo_dc计算方法为正负极直流电压相加除于二经带通滤波后取有效值。
应用于电压源换流器的故障恢复方法中检测到零序电压或不平衡电压满足要求后，同时闭锁各换流站，闭锁期间交流侧零序电压Uo_ac大于等于设定值Uo_set2超过一定时间Δt2则定位为故障站，否则为非故障站，定位出故障站后非故障站恢复解锁运行，非故障站首先直流电压控制站先恢复解锁运行，有功功率控制站后恢复解锁运行，故障站检测到交流侧零序电压Uo_ac不大于设定值Uo_set3超过一定时间Δt3后恢复故障站解锁运行。
一种应用于电压源换流器的故障恢复方法采用同时闭锁各换流站，闭锁期间交流侧零序电压Uo_ac大于等于设定值Uo_set2超过一定时间Δt2则定位为故障站，否则为非故障站，定位出故障站后非故障站恢复解锁运行，非故障站中直流电压控制站先恢复解锁运行，非故障站中有功功率控制站后恢复解锁运行，故障站投入零序电压控制恢复解锁运行。
一种应用于电压源换流器的故障恢复方法采用先闭锁处于有功功率控制的换流站，闭锁期间处于有功功率控制的各换流站交流侧零序电压Uo_ac大于设定值Uo_set2超过一定时间Δt2则定位为故障有功功率控制站，否则为非故障有功功率控制站，其它非故障有功功率站恢复解锁运行，故障站有功功率换流站可以选择检测到交流侧零序电压Uo_ac不大于设定值Uo_set3超过一定时间Δt3后恢复故障站解锁运行，也可以选择投入零序电压控制直接恢复解锁运行。
进一步的，有功功率站闭锁期间直流电压控制站交流侧零序电压Uo_ac大于设定值Uo_set2超过一定时间Δt2则定位为故障站为直流电压站，需要进一步闭锁处于直流电压控制的换流站，检测处于直流电压控制的换流站交流侧零序电压Uo_ac大于设定值Uo_set2超过一定时间Δt2则为故障直流电压控制站，否则为非故障直流电压控制站；除故障直流电压控制站外如有非故障直流电压控制站，则非故障直流电压控制站解锁运行，然后有功功率站恢复解锁运行，故障站直流电压控制站可以选择检测到交流侧零序电压Uo_ac不大于设定值Uo_set3超过一定时间Δt3后恢复故障站解锁运行，也可以选择投入零序电压控制直接恢复解锁运行；除故障直流电压控制站外如无非故障直流电压控制站，可以选择故障站直流电压控制站投入零序电压控制直接恢复解锁运行，然后有功功率站恢复解锁运行，也可选择将某有功功率控制站转换为直流电压控制站先解锁运行，其余有功功率控制站后解锁运行，故障站直流电压控制站检测到交流侧零序电压Uo_ac不大于设定值Uo_set3超过一定时间Δt3后恢复故障站解锁运行。
应用于电压源换流器的故障恢复方法通过将零序电压检测控制生成的零序电压参考值Uoref叠加在外环功率控制和内环电流控制产生基于正负序控制的电压参考波Uref上，生成新的电压参考波Uref_new来投入零序电压控制。根据交流电压计算零序电压Uo_ac方法为三相交流电压相加除于三，根据直流电压计算零序电压Uo_dc方法为正负极电压相加除于二，Uoref通过选择器选择Uo_ac或Uo_dc，其详细控制框图如图4所示。
一种应用于电压源换流器的故障恢复方法，按照故障特征，各故障设定值取值范围如下：Uo_set1取值范围为0.01倍交流额定电压至0.8倍额定交流电压，Δt1取值范围为0s至6000s；Uo_set2取值范围为0.01倍交流额定电压至0.8倍额定交流电压，Δt2取值范围为0s至6000s；Uo_set3取值范围为0.01倍交流额定电压至0.8倍额定交流电压，Δt3取值范围为0s至6000s。
一种应用于电压源换流器的故障恢复方法，换流器为包含全桥子模块、类全桥子模块拓扑结构时，全桥子、类全桥模块和钳位双子模块采用全闭锁或者半闭锁方式闭锁换流器，类全桥和全桥半闭锁子模块导通状态如表2和表3所示：
表2类全桥子模块工作状态
Figure PCTCN2017081890-appb-000008
表3全桥子模块工作状态
Figure PCTCN2017081890-appb-000009
钳位双子模块导通状态如表4所示：
表4钳位双子模块工作状态
Figure PCTCN2017081890-appb-000010
换流器为半桥子模块拓扑结构采用闭锁方式实现换流站闭锁，半桥拓扑结构闭锁子模块导通状态表如表1所示：
表1半桥子模块工作状态
Figure PCTCN2017081890-appb-000011
进一步的，在提供一种电压源换流器的故障恢复方法外还提供一种应用于电压源换流器的故障恢复系统，电压源型换流站恢复系统包含检测模块、闭锁模块、故障判断定位模块、故障恢复模块，检测模块检测交流侧零序电压Uo_ac或者直 流侧不平衡电压Uo_dc大于设定值Uo_set1超过一定时间Δt1，闭锁模块闭锁换流器，闭锁期间故障判断定位模块检测各站交流侧零序电压Uo_ac大于设定值Uo_set2超过一定时间Δt2则定位为故障站，否则为非故障站。定位到故障站后故障恢复模块对非故障站恢复解锁运行，故障站交流侧零序电压Uo_ac不大于设定值Uo_set3超过一定时间Δt3后恢复故障站解锁运行或故障站投入零序电压控制后直接恢复解锁运行。
一种应用于电压源换流器的故障恢复系统中检测模块交流侧零序电压Uo_ac计算方法为三相交流电压相加除于三后经带通滤波后取有效值，直流侧不平衡电压Uo_dc计算方法为正负极直流电压相加除于二经带通滤波后取有效值。
一种应用于电压源换流器的故障恢复系统中闭锁模块可以同时闭锁各换流站，闭锁期间故障判断定位模块检测交流侧零序电压Uo_ac大于等于设定值Uo_set2超过一定时间Δt2则定位为故障站，否则为非故障站，定位出故障站后故障恢复模块恢复非故障站恢复解锁运行，非故障站首先直流电压控制站先恢复解锁运行，有功功率控制站后恢复解锁运行，故障站可以检测到交流侧零序电压Uo_ac不大于设定值Uo_set3超过一定时间Δt3后恢复故障站解锁运行；也可以故障站投入零序电压控制恢复解锁运行。
一种应用于电压源换流器的故障恢复系统中闭锁模块闭锁处于有功功率控制的换流站，闭锁期间故障判断定位模块检测处于有功功率控制的各换流站交流侧零序电压Uo_ac大于设定值Uo_set2超过一定时间Δt2则定位为故障有功功率控制站，否则为非故障有功功率控制站，定位出故障站后故障恢复模块恢复其它非故障有功功率站恢复解锁运行，故障站有功功率换流站可以选择检测到交流侧零序电压Uo_ac不大于设定值Uo_set3超过一定时间Δt3后恢复故障站解锁运行，也可以选择投入零序电压控制直接恢复解锁运行。
进一步的一种应用于电压源换流器的故障恢复系统，闭锁模块闭锁有功功率控制站，有功功率站闭锁期间故障判断定位模块检测直流电压控制站交流侧零序电压Uo_ac大于设定值Uo_set2超过一定时间Δt2则定位为故障站为直流电压站，监测到故障站为直流电压控制站后需要进一步闭锁处于直流电压控制的换流站，故障判断定位模块检测处于直流电压控制的换流站交流侧零序电压Uo_ac大于设定值Uo_set2超过一定时间Δt2则为故障直流电压控制站，否则为非故障直流电压控制站；除故障直流电压控制站外如有非故障直流电压控制站，故障恢复模块 恢复则非故障直流电压控制站解锁运行，然后恢复有功功率站解锁运行，故障站直流电压控制站可以选择检测到交流侧零序电压Uo_ac不大于设定值Uo_set3超过一定时间Δt3后恢复故障站解锁运行，也可以选择投入零序电压控制直接恢复解锁运行；除故障直流电压控制站外如无非故障直流电压控制站，故障恢复模块可以选择故障站直流电压控制站投入零序电压控制直接恢复解锁运行，然后有功功率站恢复解锁运行，也可选择将某有功功率控制站转换为直流电压控制站先解锁运行，其余有功功率控制站后解锁运行，故障站直流电压控制站检测到交流侧零序电压Uo_ac不大于设定值Uo_set3超过一定时间Δt3后恢复故障站解锁运行。
一种应用于电压源换流器的故障恢复系统，将零序电压检测控制生成的零序电压参考值Uoref叠加在外环功率控制和内环电流控制产生基于正负序控制的电压参考波Uref上，生成新的电压参考波Uref_new来投入零序电压控制。根据交流电压计算零序电压Uo_ac方法为三相交流电压相加除于三，根据直流电压计算零序电压Uo_dc方法为正负极电压相加除于二，Uoref通过选择器选择Uo_ac或Uo_dc，其详细控制框图如图4所示。
一种应用于电压源换流器的故障恢复系统，根据故障特性，各设定值取值范围为：Uo_set1取值范围为0.01倍交流额定电压至0.8倍额定交流电压，Δt1取值范围为0s至6000s；Uo_set2取值范围为0.01倍交流额定电压至0.8倍额定交流电压，Δt2取值范围为0s至6000s；Uo_set3取值范围为0.01倍交流额定电压至0.8倍额定交流电压，Δt3取值范围为0s至6000s。
上述的一种应用于电压源换流器的故障恢复系统，换流器为包含全桥子模块、类全桥子模块拓扑结构时，全桥子、类全桥模块和钳位双子模块采用全闭锁或者半闭锁方式闭锁换流器，类全桥和全桥半闭锁子模块导通状态如表2和表3所示，钳位双子模块导通状态如表4所示；换流器为半桥子模块拓扑结构采用闭锁方式实现换流站闭锁，半桥拓扑结构闭锁子模块导通状态表如表1所示。
在实际应用中，也可以根据需要综合故障定位方法，依次闭锁各个换流站进行检测，实现交流故障的检测定位，故障定位后，故障恢复时，也可以采用非故障站叠加零序电压控制以及故障站非故障站均叠加零序电压控制恢复运行，但均在本方案研究方法之内。
需要说明的是，本实施方案针对两端柔性直流输电为例进行说明，本发明适用于适用于两个或以上电压源型换流站构成的柔性交直流输电系统，例如两端/ 多端柔性直流输电、直流配电网、统一潮流控制器(UPFC)等。同时本实施方案以全桥、类全桥、钳位双子模块和半桥为例进行说明，但本方案适用于任何电压源换流器构成的两端及多端系统，例如多重化换流器拓扑、X-MMC子模块拓扑结构等。
以上实施例仅为说明本发明的技术思想，不能以此限定本发明的保护范围，凡是按照本发明提出的技术思想，在技术方案基础上所做的任何改动，均落入本发明保护范围之内。

Claims (46)

  1. 一种应用于电压源换流器的故障定位方法，其特征在于：当电压源型换流站检测到交流侧零序电压Uo_ac或者直流侧不平衡电压Uo_dc大于设定的第一阈值Uo_set1、且持续超过设定时间Δt1时，闭锁换流器；
    闭锁期间，当检测到交流侧零序电压Uo_ac大于设定的第二阈值Uo_set2、且持续超过设定时间Δt2时，则该换流站为故障站，否则为非故障站。
  2. 如权利要求1所述的一种应用于电压源换流器的故障定位方法，其特征在于：所述交流侧零序电压Uo_ac的计算方法为，三相交流电压相加之和除以三，再经过带通滤波后取有效值；
    所述直流侧不平衡电压Uo_dc的计算方法为，正、负极直流电压相加之和除以二，再经过带通滤波后取有效值。
  3. 如权利要求1所述的一种应用于电压源换流器的故障定位方法，其特征在于：所述闭锁换流器这一步骤，可以同时闭锁各换流站，也可以先闭锁处于有功功率控制的换流站，检测出处于直流电压控制的换流站故障后再闭锁直流电压控制的换流站。
  4. 如权利3所述的一种应用于电压源换流器的故障定位方法，其特征在于：闭锁换流器步骤中，同时闭锁各换流站时，闭锁期间交流零序电压Uo_ac大于等于设定的第二阀值Uo_set2超过设定时间Δt2则定位为故障站，否则为非故障站。
  5. 如权利要求3所述的一种应用于电压源换流器的故障定位方法，其特征在于：所述先闭锁处于有功功率控制的换流站的步骤中，闭锁期间，当处于有功功率控制的换流站交流侧零序电压Uo_ac大于设定的第二阈值Uo_set2、且持续超过设定时间Δt2，则定位为故障有功功率控制的换流站，否则为非故障有功功率控制的换流站。
  6. 如权利要求3所述的一种应用于电压源换流器的故障定位方法，其特征在于：先闭锁有功功率控制站，有功功率站闭锁期间直流电压控制站交流侧零序电压Uo_ac大于设定第一阈值Uo_set1超过一定时间Δt1则定位为故障站为直流电压控制站，需要进一步再闭锁处于直流电压控制的换流站的步骤中当检测到处于直流电压控制的换流站的交流侧零序电压Uo_ac大于设定的第二阈值Uo_set2、且持续超过设定时间Δt2，则定位为故障直流电压控制的换流站，否则为非故障 直流电压控制的换流站。
  7. 如权利要求1所述的一种应用于电压源换流器的故障定位方法，其特征在于：所述Uo_set1取值范围为0.01倍交流额定电压至0.8倍额定交流电压，Δt1取值范围为0s至6000s。
  8. 如权利要求1所述的一种应用于电压源换流器的故障定位方法，其特征在于：Uo_set2取值范围为0.01倍交流额定电压至0.8倍额定交流电压，Δt2取值范围为0s至6000s。
  9. 如权利要求1所述的一种应用于电压源换流器的故障定位方法，其特征在于，当所述电压源换流器包含全桥子模块、类似全桥子模块或钳位双子模块拓扑结构时，采用全闭锁或者半闭锁方式闭锁换流器。
  10. 如权利要求1所述的一种应用于电压源换流器的故障定位方法，其特征在于，当所述电压源换流器为半桥子模块拓扑结构时，采用闭锁方式实现闭锁换流站。
  11. 一种应用于电压源换流器的故障定位系统，其特征在于：所述系统包括检测模块、闭锁模块和故障判断定位模块；
    所述检测模块在检测到交流侧零序电压Uo_ac或者直流侧不平衡电压Uo_dc大于设定的第一阈值Uo_set1、且持续超过设定时间Δt1时，闭锁模块闭锁换流器，闭锁期间，当故障判断定位模块检测到交流侧零序电压Uo_ac大于设定的第二阈值Uo_set2、且持续超过设定时间Δt2，则该换流站定位为故障站，否则为非故障站。
  12. 如权利要求11所述的一种应用于电压源换流器的故障定位系统，其特征在于：所述检测模块中，交流侧零序电压Uo_ac的计算方法为，三相交流电压相加之和除以三，再经过带通滤波后取有效值；直流侧电压不平衡电压Uo_dc的计算方法为，正负极直流电压相加之和除以二，再经过带通滤波后取有效值。
  13. 如权利要求11所述的一种应用于电压源换流器的故障定位系统，其特征在于：所述闭锁模块闭锁换流器的过程中，可以同时闭锁各换流站，也可以先闭锁有功功率控制的换流站，再闭锁直流电压控制的换流站。
  14. 如权利11所述的一种应用于电压源换流器的故障定位系统，其特征在于：当闭锁模块这一步骤中，同时闭锁各换流站，闭锁期间交流零序电压Uo_ac大于等于设定的第二阀值Uo_set2超过设定时间Δt2则定位为故障站，否则为非故 障站。
  15. 如权利要求13所述的一种应用于电压源换流器的故障定位系统，其特征在于：闭锁模块闭锁处于有功功率控制的换流站时，如果闭锁期间，故障判断定位模块检测到处于有功功率控制的换流站交流侧零序电压Uo_ac大于设定的第二阀值Uo_set2超过设定时间Δt2则定位为故障有功功率控制的换流站，否则为非故障有功功率控制的换流站。
  16. 如权利要求14所述的一种应用于电压源换流器的故障定位系统，其特征在于：闭锁模块闭锁有功功率控制站，有功功率站闭锁期间故障判断定位模块检测直流电压控制站交流侧零序电压Uo_ac大于设定值Uo_set1超过一定时间Δt1则定位为故障站为直流电压站，需要进一步所述闭锁模块闭锁处于直流电压控制的换流站，检测处于直流电压控制换流站的交流侧零序电压Uo_ac大于设定的第二阈值Uo_set2、且持续超过设定时间Δt2，则定位为故障直流电压控制的换流站，否则定位为非故障直流电压控制的换流站。
  17. 如权利要求11所述的一种应用于电压源换流器的故障定位系统，其特征在于：Uo_set1取值范围为0.01倍交流额定电压至0.8倍额定交流电压，Δt1取值范围为0s至6000s。
  18. 如权利要求11所述的一种应用于电压源换流器的故障定位系统，其特征在于：Uo_set2取值范围为0.01倍交流额定电压至0.8倍额定交流电压，Δt2取值范围为0s至6000s。
  19. 如权利要求11所述的一种应用于电压源换流器的故障定位系统，其特征在于，当换流器为包括全桥子模块、类似全桥子模块或钳位双子模块拓扑结构时，采用全闭锁或者半闭锁方式闭锁换流器。
  20. 如权利要求11所述的一种应用于电压源换流器的故障定位系统，其特征在于，当换流器为半桥子模块拓扑结构时，采用闭锁方式实现换流站闭锁。
  21. 一种应用于电压源换流器的故障恢复方法，其特征在于：当电压源型换流站检测到交流侧零序电压Uo_ac或者直流侧不平衡电压Uo_dc大于设定的第一阈值Uo_set1、且持续超过设定时间Δt1时，闭锁换流器，闭锁期间各站交流侧零序电压Uo_ac大于设定的第二阈值Uo_set2、且持续超过设定时间Δt2则将其定位为故障站，否则为非故障站；
    定位到故障站后非故障站恢复解锁运行，故障站可以选择投入零序电压控制 后直接解锁运行，故障站也可以选择交流侧零序电压Uo_ac不大于小于或者等于设定的第三阈值Uo_set3、且持续超过设定时间Δt3后，恢复故障站解锁运行。
  22. 如权利要求21所述的一种应用于电压源换流器的故障恢复方法，其特征在于：交流侧零序电压Uo_ac计算方法为，三相交流电压相加之和除以三，再经过带通滤波后取有效值；直流侧不平衡电压Uo_dc的计算方法为，正负极直流电压相加之和除以二，再经过带通滤波后取有效值。
  23. 如权利要求21所述的一种应用于电压源换流器的故障恢复方法，其特征在于：同时闭锁各换流站，闭锁期间交流侧零序电压Uo_ac大于等于设定的第二阈值Uo_set2、且持续超过设定时间Δt2，则定位为故障站，否则为非故障站；
    定位出故障站后非故障站恢复解锁运行，非故障站中，直流电压控制站先恢复解锁运行，有功功率控制站后恢复解锁运行，故障站检测到交流侧零序电压Uo_ac不大于小于等于设定的第三阈值Uo_set3、且持续超过一定时间Δt3后，恢复故障站解锁运行。
  24. 如权利要求21所述的一种应用于电压源换流器的故障恢复方法，其特征在于：同时闭锁各换流站，闭锁期间交流侧零序电压Uo_ac大于等于设定的第二阈值Uo_set2、且持续超过一定时间Δt2，则定位为故障站，否则为非故障站；
    定位出故障站后非故障站恢复解锁运行，非故障站中直流电压控制站先恢复解锁运行，非故障站中有功功率控制站后恢复解锁运行，故障站投入零序电压控制恢复解锁运行。
  25. 如权利要求21所述的一种应用于电压源换流器的故障恢复方法，其特征在于：闭锁处于有功功率控制的换流站，闭锁期间处于有功功率控制的各换流站交流侧零序电压Uo_ac大于设定的第二阈值Uo_set2、且持续超过设定时间Δt2，则定位为故障有功功率控制站，否则为非故障有功功率控制站；
    其它非故障有功功率控制站恢复解锁运行，故障站有功功率换流站可以选择检测到交流侧零序电压Uo_ac不大于小于等于设定的第三阈值Uo_set3、且持续超过设定时间Δt3后，恢复故障站解锁运行，或者，选择投入零序电压控制直接恢复解锁运行。
  26. 如权利要求21所述的一种应用于电压源换流器的故障恢复方法，其特征在于：闭锁有功功率控制站，有功功率控制站闭锁期间直流电压控制站交流侧零序电压Uo_ac大于设定的第二阈值Uo_set1、且持续超过设一定时间Δt1，则定 位为故障站为直流电压站；
    进一步闭锁处于直流电压控制的换流站，检测处于直流电压控制的换流站交流侧零序电压Uo_ac大于设定的第二阈值Uo_set2且持续超过设定时间Δt2，则为故障直流电压控制站，否则为非故障直流电压控制站；
    除故障直流电压控制站外如有非故障直流电压控制站，则非故障直流电压控制站解锁运行，然后有功功率站恢复解锁运行，故障站直流电压控制站可以选择检测到交流侧零序电压Uo_ac不大于小于等于设定的第三阈值Uo_set3、且持续超过设定时间Δt3后，恢复故障站解锁运行，也可以选择投入零序电压控制直接恢复解锁运行；
    除故障直流电压控制站外如无非故障直流电压控制站，可以选择故障站直流电压控制站投入零序电压控制直接恢复解锁运行，然后有功功率站恢复解锁运行，也可选择将某有功功率控制站转换为直流电压控制站先解锁运行，其余有功功率控制站后解锁运行，故障站直流电压控制站检测到交流侧零序电压Uo_ac不大于小于等于设定的第三阈值Uo_set3、且持续超过设定时间Δt3后，恢复故障站解锁运行。
  27. 如权利要求21所述的一种应用于电压源换流器的故障恢复方法，其特征在于：将零序电压检测控制生成的零序电压参考值Uoref叠加在原有的电压参考波Uref上，生成新的电压参考波Uref_new来进行控制。
  28. 如权利要求28所述的一种应用于电压源换流器的故障恢复方法，其特征在于：根据交流电压计算零序电压Uo_rac方法为三相交流电压相加之和除以三，根据直流电压计算零序电压Uo_rdc方法为正负极电压相加之和除以二，Uoref通过选择器选择Uo_rac或Uo_rdc。
  29. 如权利要求21所述的一种应用于电压源换流器的故障恢复方法，其特征在于：Uo_set1取值范围为0.01倍交流额定电压至0.8倍额定交流电压，Δt1取值范围为0s至6000s。
  30. 如权利要求21所述的一种应用于电压源换流器的故障恢复方法，其特征在于：Uo_set2取值范围为0.01倍交流额定电压至0.8倍额定交流电压，Δt2取值范围为0s至6000s。
  31. 如权利要求21所述的一种应用于电压源换流器的故障恢复方法，其特征在于：Uo_set3取值范围为0.01倍交流额定电压至0.8倍额定交流电压，Δt3取 值范围为0s至6000s。
  32. 如权利要求21所述的一种应用于电压源换流器的故障恢复方法，其特征在于，换流器为包含全桥子模块、类似全桥子模块或钳位双子模块拓扑结构时，采用全闭锁或者半闭锁方式闭锁换流器。
  33. 如权利要求21所述的一种应用于电压源换流器的故障恢复方法，其特征在于，换流器为半桥子模块拓扑结构采用闭锁方式实现换流站闭锁。
  34. 一种应用于电压源换流器的故障恢复系统，其特征在于：所述系统包含检测模块、闭锁模块、故障判断定位模块、故障恢复模块；
    所述检测模块检测交流侧零序电压Uo_ac或者直流侧不平衡电压Uo_dc大于设定的第一阈值Uo_set1、且持续超过设定时间Δt1，闭锁模块闭锁换流器，闭锁期间故障判断定位模块检测各站交流侧零序电压Uo_ac大于设定的第二阈值Uo_set2、且持续超过设定时间Δt2，则定位为故障站，否则为非故障站；
    定位到故障站后故障恢复模块对非故障站恢复解锁运行，故障站可以选择投入零序电压控制后直接恢复解锁运行，故障站也可以选择交流侧零序电压Uo_ac不大于小于等于设定的第三阈值Uo_set3，且持续超过设定时间Δt3后，恢复故障站解锁运行。
  35. 如权利要求34所述的一种应用于电压源换流器的故障恢复系统，其特征在于：检测模块交流侧零序电压Uo_ac计算方法为三相交流电压相加之和除以三，再经带通滤波后取有效值，直流侧不平衡电压Uo_dc计算方法为正负极直流电压相加之和除以二，再经带通滤波后取有效值。
  36. 如权利要求34所述的一种应用于电压源换流器的故障恢复系统，其特征在于：闭锁模块同时闭锁各换流站，闭锁期间故障判断定位模块检测交流侧零序电压Uo_ac大于等于设定的第二阈值Uo_set2、且持续超过设定时间Δt2，则定位为故障站，否则为非故障站；
    定位出故障站后故障恢复模块恢复非故障站恢复解锁运行，非故障站首先直流电压控制站先恢复解锁运行，有功功率控制站后恢复解锁运行，故障站检测到交流侧零序电压Uo_ac不大于小于等于设定的第三阈值Uo_set3、且持续超过设定时间Δt3后，恢复故障站解锁运行。
  37. 如权利要求34所述的一种应用于电压源换流器的故障恢复方法，其特征在于：闭锁模块同时闭锁各换流站，闭锁期间故障判断定位模块检测交流侧零 序电压Uo_ac大于等于设定的第二阈值Uo_set2、且持续超过设定时间Δt2，则定位为故障站，否则为非故障站；
    定位出故障站后故障恢复模块恢复非故障站恢复解锁运行，非故障站中直流电压控制站先恢复解锁运行，非故障站中有功功率控制站后恢复解锁运行，故障站投入零序电压控制恢复解锁运行。
  38. 如权利34所述的一种应用于电压源换流器的故障恢复系统，其特征在于：闭锁模块闭锁处于有功功率控制的换流站，闭锁期间故障判断定位模块检测处于有功功率控制的各换流站交流侧零序电压Uo_ac大于设定的第二阈值Uo_set2、且持续超过设定时间Δt2，则定位为故障有功功率控制站，否则为非故障有功功率控制站；
    定位出故障站后故障恢复模块恢复其它非故障有功功率站恢复解锁运行，故障站有功功率换流站可以选择检测到交流侧零序电压Uo_ac不大于小于等于设定的第三阈值Uo_set3、且持续超过设定时间Δt3后，恢复故障站解锁运行，也可以选择投入零序电压控制直接恢复解锁运行。
  39. 如权利34所述的一种应用于电压源换流器的故障恢复系统，其特征在于：闭锁模块闭锁有功功率控制站，有功功率站闭锁期间故障判断定位模块检测直流电压控制站交流侧零序电压Uo_ac大于设定的第二阈值Uo_set1、且持续超过设定时间Δt1，则定位为故障站为直流电压站，监测到故障站为直流电压控制站后需要进一步闭锁处于直流电压控制的换流站，故障判断定位模块检测处于直流电压控制的换流站交流侧零序电压Uo_ac大于设定的第二阈值Uo_set2且持续超过设定时间Δt2，则为故障直流电压控制站，否则为非故障直流电压控制站；
    除故障直流电压控制站外如有非故障直流电压控制站，故障恢复模块恢复则非故障直流电压控制站解锁运行，然后恢复有功功率站解锁运行，故障站直流电压控制站可以选择检测到交流侧零序电压Uo_ac不大于小于等于设定的第三阈值Uo_set3、且持续超过设定时间Δt3后，恢复故障站解锁运行，也可以选择投入零序电压控制直接恢复解锁运行；
    除故障直流电压控制站外如无非故障直流电压控制站，故障恢复模块可以选择故障站直流电压控制站投入零序电压控制直接恢复解锁运行，然后有功功率站恢复解锁运行，也可选择将某有功功率控制站转换为直流电压控制站先解锁运行，其余有功功率控制站后解锁运行，故障站直流电压控制站检测到交流侧零序电压 Uo_ac不大于小于等于设定的第三阈值Uo_set3、且持续超过设定时间Δt3后，恢复故障站解锁运行。
  40. 如权利34所述的一种应用于电压源换流器的故障恢复系统，其特征在于：将零序电压检测控制生成的零序电压参考值Uoref叠加在原有的电压参考波Uref上，生成新的电压参考波Uref_new来进行控制。
  41. 如权利34所述的一种应用于电压源换流器的故障恢复系统，其特征在于：根据交流电压计算零序电压Uo_rac方法为三相交流电压相加之和除以三，根据直流电压计算零序电压Uo_rdc方法为正负极电压相加之和除以二，Uoref通过选择器选择Uo_rac或Uo_rdc。
  42. 如权利34所述的一种应用于电压源换流器的故障恢复系统，其特征在于：Uo_set1取值范围为0.01倍交流额定电压至0.8倍额定交流电压，Δt1取值范围为0s至6000s。
  43. 如权利34所述的一种应用于电压源换流器的故障恢复系统，其特征在于：Uo_set2取值范围为0.01倍交流额定电压至0.8倍额定交流电压，Δt2取值范围为0s至6000s。
  44. 如权利34所述的一种应用于电压源换流器的恢复系统系统，其特征在于：Uo_set3取值范围为0.01倍交流额定电压至0.8倍额定交流电压，Δt3取值范围为0s至6000s。
  45. 如权利34所述的一种应用于电压源换流器的故障恢复系统，其特征在于，换流器为包含全桥子模块、类似全桥子模块或钳位双子模块拓扑结构时，采用全闭锁或者半闭锁方式闭锁换流器。
  46. 如权利34所述的一种应用于电压源换流器的故障恢复系统，其特征在于，换流器为半桥子模块拓扑结构采用闭锁方式实现换流站闭锁。
PCT/CN2017/081890 2016-05-05 2017-04-25 一种电压源换流器的故障定位及恢复方法和系统 WO2017190608A1 (zh)

Priority Applications (10)

Application Number Priority Date Filing Date Title
ES17792434T ES2847256T3 (es) 2016-05-05 2017-04-25 Método y sistema para posicionamiento de fallas y recuperación del convertidor de fuente de voltaje
BR112018069099-6A BR112018069099B1 (pt) 2016-05-05 2017-04-25 Método e sistema para posicionamento de falha e recuperação de conversor de fonte de tensão
US16/098,878 US10476261B2 (en) 2016-05-05 2017-04-25 Method and system for fault positioning and recovery of voltage source converter
EP19171554.9A EP3537556B1 (en) 2016-05-05 2017-04-25 Method and system for fault locating and recovery of voltage source converter
MX2018011338A MX2018011338A (es) 2016-05-05 2017-04-25 Metodo y sistema para localizacion y recuperacion de fallas de convertidor de fuente de voltaje.
DK17792434.7T DK3419138T3 (da) 2016-05-05 2017-04-25 Fremgangsmåde og system til fejllokalisering og genopretning af spændingskildekonverter
RU2018135694A RU2692674C1 (ru) 2016-05-05 2017-04-25 Способ и система для определения неисправностей и восстановления преобразователя напряжения
KR1020187027092A KR102082597B1 (ko) 2016-05-05 2017-04-25 전압원 컨버터의 고장 위치 확인 및 회복을 위한 방법 및 시스템
EP17792434.7A EP3419138B1 (en) 2016-05-05 2017-04-25 Method and system for fault positioning and recovery of voltage source converter
CA3018404A CA3018404C (en) 2016-05-05 2017-04-25 Method and system for fault positioning and recovery of voltage source converter

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CN201610294949.6A CN105896586B (zh) 2016-05-05 2016-05-05 一种电压源换流站的故障定位及恢复方法和系统
CN201610294949.6 2016-05-05

Publications (1)

Publication Number Publication Date
WO2017190608A1 true WO2017190608A1 (zh) 2017-11-09

Family

ID=56702226

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/CN2017/081890 WO2017190608A1 (zh) 2016-05-05 2017-04-25 一种电压源换流器的故障定位及恢复方法和系统

Country Status (12)

Country Link
US (1) US10476261B2 (zh)
EP (2) EP3537556B1 (zh)
KR (1) KR102082597B1 (zh)
CN (1) CN105896586B (zh)
BR (1) BR112018069099B1 (zh)
CA (1) CA3018404C (zh)
DK (2) DK3537556T3 (zh)
ES (2) ES2872027T3 (zh)
MX (1) MX2018011338A (zh)
PT (2) PT3419138T (zh)
RU (1) RU2692674C1 (zh)
WO (1) WO2017190608A1 (zh)

Families Citing this family (18)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105896586B (zh) * 2016-05-05 2018-08-17 南京南瑞继保电气有限公司 一种电压源换流站的故障定位及恢复方法和系统
CN106786713B (zh) * 2016-11-25 2019-04-09 南京南瑞继保电气有限公司 一种电压源换流器单元拓扑结构及控制方法
CN108280271B (zh) * 2018-01-04 2021-12-21 全球能源互联网研究院 基于开关周期平均原理的统一潮流控制器等效建模方法
CN110361623B (zh) * 2019-07-16 2021-07-23 北京四方继保自动化股份有限公司 一种多端直流系统单点接地故障定位的小电阻投切方法
CN110994624B (zh) * 2019-11-14 2023-02-24 国网新疆电力有限公司 避免特高压直流换流站故障引起电压越限的电压控制方法
CN112162174B (zh) * 2020-09-03 2024-04-26 国电南瑞科技股份有限公司 基于营配一体的台区故障定位方法及系统
CN114156930B (zh) * 2020-09-07 2024-04-26 许继集团有限公司 一种特高压直流输电系统逆变侧交流故障恢复方法
CN112332384B (zh) * 2020-10-26 2022-11-01 西安热工研究院有限公司 一种避免发电厂厂用系统误失电的方法
CN112366705B (zh) * 2020-11-16 2023-04-07 深圳供电局有限公司 一种柔直换流站与备自投装置时序协调方法及系统
CN112787528B (zh) * 2020-12-30 2022-12-20 国网河北省电力有限公司沧州供电分公司 9a-mmc的控制方法及终端设备
CN113009275A (zh) * 2021-02-22 2021-06-22 天津大学 一种柔性直流接入的交流混合线路双端故障测距方法
CN112886556B (zh) * 2021-03-04 2022-12-16 中国南方电网有限责任公司 柔性直流输电交流连接线区单相接地故障控制保护方法
CN113162026B (zh) * 2021-03-16 2022-08-12 中国农业大学 一种基于vsc的交直流混合配电网故障恢复方法和系统
WO2022198063A1 (en) * 2021-03-19 2022-09-22 Mersen Usa Ep Corp. Arc fault detection based on photovoltaic operating characteristics and extraction of pink noise behavior
CN113629703B (zh) * 2021-07-28 2024-05-07 南方电网科学研究院有限责任公司 一种常规直流系统故障恢复控制的优化方法
CN113922344A (zh) * 2021-09-29 2022-01-11 广东电网有限责任公司 交流故障保护方法、装置、电子设备及存储介质
CN116073363B (zh) * 2022-11-24 2024-05-10 中南大学 海上风电经柔直并网系统调频过程故障电流主动抑制方法
CN116345423B (zh) * 2023-03-22 2023-12-05 华中科技大学 一种面向海上风电柔直系统的故障抑制方法、装置和系统

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2004017505A1 (en) * 2002-08-16 2004-02-26 Abb Ab An installation for transmission of electric power and a method for operation of such an installation
CN103050966A (zh) * 2012-12-07 2013-04-17 国网智能电网研究院 模块化多电平柔性直流输电系统的接地装置及其设计方法
CN104242250A (zh) * 2014-10-14 2014-12-24 国家电网公司 一种模块化多电平换流器的继电保护方法及系统
CN104578009A (zh) * 2015-01-19 2015-04-29 国家电网公司 一种换流器桥差保护防误动的方法
CN105896586A (zh) * 2016-05-05 2016-08-24 南京南瑞继保电气有限公司 一种电压源换流器的故障定位及恢复方法和系统

Family Cites Families (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP3415129B2 (ja) * 2002-02-06 2003-06-09 三菱電機株式会社 インバータの故障検出方式
US7884588B2 (en) * 2008-04-10 2011-02-08 Stmicroelectronics S.R.L. Control method and device for a system of interleaved converters using a designated master converter
RU2432660C1 (ru) * 2010-07-27 2011-10-27 Общество с ограниченной ответственностью "НПП Бреслер" (ООО "НПП Бреслер") Способ автоматического включения резервного питания потребителей с повышенной надежностью по цепям напряжения
KR101136181B1 (ko) * 2010-08-23 2012-04-17 아주대학교산학협력단 전력변환장치의 고장 진단 장치 및 그 방법
PL2671297T3 (pl) * 2011-02-01 2018-10-31 Siemens Aktiengesellschaft Sposób usuwania błędu na przewodzie prądu stałego wysokiego napięcia, instalacja do przenoszenia prądu elektrycznego przez przewód prądu stałego wysokiego napięcia i przetwornica
CN103947096B (zh) * 2011-10-21 2016-09-21 Abb研究有限公司 用于检测ac/dc转换器中失效整流器的方法和系统
JP5905368B2 (ja) * 2012-09-13 2016-04-20 ニチコン株式会社 Ｄｃ／ｄｃコンバータ、および電源システム
CN103280989B (zh) * 2013-05-15 2017-02-08 南京南瑞继保电气有限公司 一种换流器及其控制方法
DE102013212426A1 (de) * 2013-06-27 2014-12-31 Siemens Aktiengesellschaft Umrichteranordnung mit parallel geschalteten Mehrstufen-Umrichtern sowie Verfahren zu deren Steuerung
JP6058148B2 (ja) * 2013-09-26 2017-01-11 三菱電機株式会社 電力変換装置及び空気調和装置

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2004017505A1 (en) * 2002-08-16 2004-02-26 Abb Ab An installation for transmission of electric power and a method for operation of such an installation
CN103050966A (zh) * 2012-12-07 2013-04-17 国网智能电网研究院 模块化多电平柔性直流输电系统的接地装置及其设计方法
CN104242250A (zh) * 2014-10-14 2014-12-24 国家电网公司 一种模块化多电平换流器的继电保护方法及系统
CN104578009A (zh) * 2015-01-19 2015-04-29 国家电网公司 一种换流器桥差保护防误动的方法
CN105896586A (zh) * 2016-05-05 2016-08-24 南京南瑞继保电气有限公司 一种电压源换流器的故障定位及恢复方法和系统

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See also references of EP3419138A4 *

Also Published As

Publication number Publication date
EP3419138B1 (en) 2020-10-28
US10476261B2 (en) 2019-11-12
DK3419138T3 (da) 2020-11-16
RU2692674C1 (ru) 2019-06-26
CN105896586A (zh) 2016-08-24
BR112018069099B1 (pt) 2023-03-14
US20190140441A1 (en) 2019-05-09
EP3537556B1 (en) 2021-02-24
EP3537556A3 (en) 2019-11-13
KR20180115302A (ko) 2018-10-22
EP3537556A2 (en) 2019-09-11
PT3419138T (pt) 2020-12-04
BR112018069099A2 (pt) 2019-01-29
CA3018404C (en) 2019-09-03
MX2018011338A (es) 2019-01-31
ES2872027T3 (es) 2021-11-02
KR102082597B1 (ko) 2020-02-27
CN105896586B (zh) 2018-08-17
EP3419138A1 (en) 2018-12-26
PT3537556T (pt) 2021-03-24
EP3419138A4 (en) 2019-11-06
ES2847256T3 (es) 2021-08-02
DK3537556T3 (da) 2021-04-12
CA3018404A1 (en) 2017-11-09

Similar Documents

Publication Publication Date Title
WO2017190608A1 (zh) 一种电压源换流器的故障定位及恢复方法和系统
Mirsaeidi et al. A predictive control strategy for mitigation of commutation failure in LCC-based HVDC systems
CN111030152B (zh) 一种储能变流器系统及其控制方法
CN105048488B (zh) 一种柔性直流网络直流短路故障穿越方法
WO2020136699A1 (ja) 電力変換装置
US10236793B2 (en) Grid connection power conversion device and output current control method thereof
CN104362651A (zh) 三相不平衡下级联型h桥静止同步无功补偿器及补偿方法
WO2012130004A1 (zh) 一种用于清除电力系统电压谐波的装置
CN105490285A (zh) 三相不平衡下双h桥mmc结构的无功补偿装置及其控制方法
CN111600494A (zh) 一种改善电力电子变压器冗余后运行性能的控制方法
CN107732952A (zh) 多端混合直流输电系统的故障响应分析方法及系统
CN107346003B (zh) 一种电压源换流器故障检测定位方法和系统
Ghazanfari et al. New submodule improving fault-tolerant capability of modular multilevel converters
Zhao et al. A fault-tolerant reconfiguration system based on pilot switch for grid-connected inverters
CN204258316U (zh) 三相不平衡下级联型h桥静止同步无功补偿器
CN105896584A (zh) 一种电压源型换流器控制零序电压的方法
Abuelnaga et al. Open circuit IGBT fault classification using phase current in a CHB converter
CN109742934B (zh) 一种基于双调制波的功率器件开路故障容错控制方法
CN106849136A (zh) 一种高压直流输电系统交流侧故障时的抗干扰控制方法
CN113131506B (zh) 抑制lcc-hvdc系统后续换相失败的定关断角控制方法及稳定器
Pham et al. Diagnosis strategies and reconfiguration of a 5-level double-boost PFC with fault-tolerant capability
Köroğlu et al. Modeling and analysis of a nonlinear adaptive filter control for interline unified power quality conditioner
WO2024042612A1 (ja) 電力変換装置
Cheng et al. Analysis of the commutation failure of inverters during open‐conductor faults at the AC side
WO2021093746A1 (zh) 混合直流换流器在线退出电路、退出方法及退出装置

Legal Events

Date Code Title Description
WWE Wipo information: entry into national phase

Ref document number: MX/A/2018/011338

Country of ref document: MX

ENP Entry into the national phase

Ref document number: 20187027092

Country of ref document: KR

Kind code of ref document: A

WWE Wipo information: entry into national phase

Ref document number: 1020187027092

Country of ref document: KR

ENP Entry into the national phase

Ref document number: 3018404

Country of ref document: CA

WWE Wipo information: entry into national phase

Ref document number: 2017792434

Country of ref document: EP

ENP Entry into the national phase

Ref document number: 2017792434

Country of ref document: EP

Effective date: 20180920

REG Reference to national code

Ref country code: BR

Ref legal event code: B01A

Ref document number: 112018069099

Country of ref document: BR

121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 17792434

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

ENP Entry into the national phase

Ref document number: 112018069099

Country of ref document: BR

Kind code of ref document: A2

Effective date: 20180919