WO2015180529A1 - 一种微网自适应过流保护方法 - Google Patents

一种微网自适应过流保护方法 Download PDF

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WO2015180529A1
WO2015180529A1 PCT/CN2015/075752 CN2015075752W WO2015180529A1 WO 2015180529 A1 WO2015180529 A1 WO 2015180529A1 CN 2015075752 W CN2015075752 W CN 2015075752W WO 2015180529 A1 WO2015180529 A1 WO 2015180529A1
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protection unit
protection
fault
local
current
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English (en)
French (fr)
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邓超平
唐志军
陈金祥
林国栋
林少真
朱维钧
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Electric Power Research Institute of State Grid Fujian Electric Power Co Ltd
State Grid Fujian Electric Power Co Ltd
State Grid Corp of China SGCC
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Electric Power Research Institute of State Grid Fujian Electric Power Co Ltd
State Grid Fujian Electric Power Co Ltd
State Grid Corp of China SGCC
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    • 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
    • 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
    • Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
    • Y02B90/00—Enabling technologies or technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02B90/20—Smart grids as enabling technology in buildings sector
    • 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
    • Y04—INFORMATION OR COMMUNICATION TECHNOLOGIES HAVING AN IMPACT ON OTHER TECHNOLOGY AREAS
    • Y04S—SYSTEMS INTEGRATING TECHNOLOGIES RELATED TO POWER NETWORK OPERATION, COMMUNICATION OR INFORMATION TECHNOLOGIES FOR IMPROVING THE ELECTRICAL POWER GENERATION, TRANSMISSION, DISTRIBUTION, MANAGEMENT OR USAGE, i.e. SMART GRIDS
    • Y04S40/00—Systems for electrical power generation, transmission, distribution or end-user application management characterised by the use of communication or information technologies, or communication or information technology specific aspects supporting them
    • Y04S40/12—Systems for electrical power generation, transmission, distribution or end-user application management characterised by the use of communication or information technologies, or communication or information technology specific aspects supporting them characterised by data transport means between the monitoring, controlling or managing units and monitored, controlled or operated electrical equipment
    • Y04S40/124—Systems for electrical power generation, transmission, distribution or end-user application management characterised by the use of communication or information technologies, or communication or information technology specific aspects supporting them characterised by data transport means between the monitoring, controlling or managing units and monitored, controlled or operated electrical equipment using wired telecommunication networks or data transmission busses

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  • the invention relates to the technical field of microgrid protection, in particular to a microgrid adaptive overcurrent protection method.
  • microgrid provides an effective technology for the comprehensive utilization of renewable energy such as solar energy, wind energy and biomass energy, as well as environmentally friendly energy sources such as natural gas and hydrogen, by constructing small or micro low-voltage power distribution systems. means.
  • renewable energy such as solar energy, wind energy and biomass energy
  • environmentally friendly energy sources such as natural gas and hydrogen
  • the micro-grid can be operated on the grid or on an island.
  • the DG's retreat and output are random.
  • part of the load is affected by its volatility.
  • the short-circuit current and direction of the fault exist. Uncertainty, which greatly affects the selectivity and sensitivity of protection. Therefore, the protection setting of the piconet becomes extremely complicated.
  • the inverter type DG is limited by the overcurrent capability of the power electronic device, and the short-circuit current value provided is limited, which causes the traditional over-current protection to be abnormal due to the small fault current or the setting value is too high. start up.
  • the grid structure of the large power grid will be fundamentally changed, and the electrical quantity characteristics after the fault change significantly, so that the traditional fault detection and relay protection modes are difficult to meet the requirements of the current safe operation of the power grid.
  • a microgrid adaptive overcurrent protection method comprising the following steps:
  • Step S1 configuring a central protection unit in the microgrid structure, configuring an in situ protection unit at each circuit breaker, and communicating between each local protection unit and between the local protection unit and the central protection unit through optical fibers;
  • Step S2 configuring adaptive current protection at each local protection unit
  • Step S3 The central protection unit collects the system operation information uploaded by the local protection unit in real time, and determines the micro network operation mode, the fault type, and the fault point location;
  • Step S4 In the grid-connected operation mode, the local protection unit samples the bus voltage and the feeder current in real time, and then determines the system impedance according to the sampled value; in the island operation mode, the local protection unit calculates the adaptive current quick-set setting according to the fault type. ;
  • Step S5 The central protection unit compares the measured current value with the set value to determine fault isolation and power restoration.
  • the central protection unit is a main controller for collecting, analyzing, processing, and feeding back information and issuing a control command
  • the local protection unit is a slave controller for collecting local electrical quantity information and a circuit breaker. location information.
  • the central protection unit includes a special adaptive component to update the protection setting in real time; when the fault occurs, each local protection unit uploads the fault information to the central protection unit; the central protection unit integration analysis includes voltage drop and current The upload information of the value size and directionality is determined to determine the micro-network operating mode, the type of fault, and the location of the fault point.
  • step S5 comparing the measured current value with the setting value to determine fault isolation and power restoration, the following steps are included:
  • Step S501 determining the measured current I m ;
  • Step S502 determining each segment of the corresponding feeder protection setting I I set ;
  • Step S503 comparing the measured current I m with the size of each segment of the corresponding feeder protection set I I set ;
  • Step S504 issuing an action instruction to the corresponding in-situ protection unit to determine fault isolation and power restoration.
  • the invention has the advantages of proposing a novel microgrid adaptive overcurrent protection method, which overcomes the problems existing in the prior art and is beneficial to realize adaptive overcurrent protection for the microgrid.
  • the new protection method using adaptive technology is especially suitable for areas with high power quality requirements.
  • FIG. 1 is a flow chart showing the implementation of the microgrid adaptive overcurrent protection method of the present invention.
  • FIG. 2 is a flow chart showing the implementation of adaptive current fast-break protection in an embodiment of the present invention.
  • FIG. 3 is a schematic diagram of a topology structure of a micro network according to an embodiment of the present invention.
  • FIG. 4 is a communication diagram of an adaptive protection system in an embodiment of the present invention.
  • FIG. 5 is a schematic diagram of a micro-network under double fault in the embodiment of the present invention.
  • FIG. 6 is a schematic diagram of a fault in an island mode in an embodiment of the present invention.
  • the microgrid adaptive overcurrent protection method of the present invention includes the following steps:
  • Step S1 a central protection unit is arranged in the microgrid structure, an in-situ protection unit is arranged at each circuit breaker, and communication between each local protection unit and between the in-situ protection unit and the central protection unit is performed through optical fibers.
  • the central protection unit is a main controller for collecting, analyzing, processing, and feeding back information and issuing control commands.
  • the local protection unit is a slave controller for collecting local electrical quantity information and circuit breaker position information.
  • Step S2 Configure adaptive current protection at each of the local protection units. It performs adaptive current protection as follows:
  • the traditional current protection quick-break setting is the current setting of the protection flowing through the three-phase short circuit of the next feeder outlet in the maximum operation mode.
  • the magnitude of the short-circuit current is related to the way the system operates, the type of short-circuit, and the location of the short-circuit point on the line.
  • K d is the fault type coefficient, 1 is taken when the three-phase short circuit is taken, and when the two-phase short circuit is taken
  • Z S is the impedance between the protection installation and the equivalent power supply of the system
  • ⁇ is the proportional coefficient, 0 ⁇ ⁇ ⁇ 1
  • Z l is the impedance of the protected feeder.
  • equation (1) contains the system equivalent impedance Z S , the protection setting value is affected by the change of Z S. Therefore, when a fault occurs, the adaptive protection should be able to calculate the three-phase short-circuit current at the end of the protection zone according to the system impedance. However, when the system has a two-phase short circuit, the actual protection range will be reduced. Therefore, when a fault occurs, the fault type should be determined first. If it is a three-phase short circuit, the three-phase short-circuit current at the end of the protection zone is set. If the two-phase is short-circuited, the two-phase short-circuit current value at the end of the protection zone is set. This greatly increases the sensitivity of the protection.
  • the criteria for adaptive protection are:
  • I m is the protection measured current
  • I I set is the speed calculation value calculated by the protection device in real time
  • the central protection unit uses the whole network information to judge the system operation mode. If it is connected to the grid, the system impedance is calculated by analyzing the real-time sampling values of the feeder voltage and current, and then the instantaneous breaking current value at each local protection unit is calculated. The measured current is compared with the set value to determine whether the protection action is correct or not. If the micro-network island is operated, the central protection unit directly calculates the quick-break current setting value of each local protection unit during the island operation, and compares the measured current with the setting value to determine the criterion of the protection action.
  • the adaptive time-limited current quick-break protection setting formula is:
  • I I set and t I 1 are the adaptive current fast-break protection setting and the definite time limit of the next line respectively;
  • I II set and t II 2 are respectively the adaptive time-limited current quick-break protection setting and the definite time limit of the line;
  • ⁇ t is the delay set to ensure selectivity, taking 0.05s.
  • the adaptive timing limit overcurrent protection setting value is as shown in equation (5):
  • I III set is the line adaptive overcurrent protection current setting value
  • K re is the relay return coefficient
  • K ss is the self-starting coefficient
  • K rel is the reliability coefficient
  • I l is the line actual load.
  • the microgrid adaptive current protection of the present invention first identifies the microgrid operation mode, and adjusts the fixed value in real time to cope with different types of faults.
  • the advantage of this protection principle is that the protected feeder is always protected to avoid the problem of reduced or even no protection range caused by the type of fault and the mode of operation of the system.
  • Step S3 The central protection unit collects the system operation information uploaded by the local protection unit in real time, and determines the operation mode of the micro network, the type of the fault, and the location of the fault point.
  • the central protection unit includes a special adaptive component to update the protection setting in real time; when the fault occurs, each local protection unit uploads the fault information to the central protection unit; the central protection unit integration analysis includes voltage drop, current value, Directional discriminating upload information to determine the piconet operating mode, fault type, and fault location.
  • the central protection unit collects the system operation information uploaded by the local protection unit in real time. The steps are as follows: 1) each local protection unit is responsible for collecting local electrical quantity information and circuit breaker position information; 2) the local protection unit will calculate the electrical quantity information and The position information of the circuit breaker is uploaded to the central protection unit; 3) The central protection unit acts as the backbone of the entire communication system, collects and analyzes the information uploaded by the local protection unit, and processes, feeds back, and issues instructions to the local protection unit. The two perform information interaction, etc. to determine the micro-network operation mode, the type of failure, and determine the location of the fault point.
  • Step S4 In the grid-connected operation mode, the local protection unit samples the bus voltage and the feeder current in real time, and then determines the system impedance according to the sampled value, that is, calculates the value of Z S ; in the island operation mode, the local protection unit according to the fault type Calculate the adaptive current fast-break setting, ie calculate the size of.
  • Step S5 The central protection unit compares the measured current value with the set value to determine fault isolation and power restoration. Specifically, the following steps are included:
  • Step S501 determining the measured current I m ;
  • Step S502 determining each segment of the corresponding feeder protection setting I I set ;
  • Step S503 comparing the measured current I m with the size of each segment of the corresponding feeder protection set I I set ;
  • Step S504 issuing an action instruction to the corresponding in-situ protection unit to determine fault isolation and power restoration.
  • FIG. 3 is a schematic diagram of a typical microgrid topology, in which both CB and switch numbers represent circuit breakers; G represents distributed power; L represents load; T represents a tie switch; and F1 to F4 are fault points.
  • 4 is an adaptive protection system communication diagram in which a red dashed line represents a communication fiber.
  • the tie switch T is open and feeders 1 and 2 operate independently. If the fault occurs at point F4, a large short-circuit current can be detected in each CB upstream of F4.
  • the time limit setting of each circuit breaker of feeder 1 is shown in Table 1, where 1 represents the closure. , 0 means disconnected.
  • the proposed adaptive direction overcurrent protection adjusts the time limit value, and particularly optimizes the time limit coordination.
  • Table 2 is the time limit for adaptive protection action for F4 point failure. It can be seen from Table 2 that this time limit action not only ensures the rapid removal of the fault but also ensures the normal power supply in the non-faulty area.
  • the unique internal structure of the microgrid determines the bidirectionality of the power flow and the bidirectionality of the fault current.
  • the smooth and counterclockwise flow of the fault current determines the two-way alternative of the protection setting scheme.
  • T is closed, and the F4 sudden failure is taken as an example, and the action time limit of the two-way scheme is given.
  • the determination of the action time limit in the table takes into account the factors such as DG capacity and directionality.
  • the fault current in island mode has a two-way possibility, and the fault current value at this time is about twice the rated current.
  • the boost current of G2 makes the fault current of CB3.2 and CB6.2 smaller, even lower than the protection setting, and the voltage drop amplitude near the fault point is large.
  • the approximate position of the fault point can be determined according to the directionality of the fault current adjacent to the CB.
  • the clockwise direction mentioned in Table 4 is the positive direction, according to the flow through CB2.2 and CB3. The fact that the fault current of 1 is in the opposite direction locates the fault point F4.
  • the DG's retreat and load switching in the grid-connected mode may cause the power flow from the micro-network side to the system side, which will not affect the normal operation of the protection system, because the real-time monitoring adjustment and protection of the central protection unit and communication system
  • the direction setting is set to meet the requirements of its normal operation.
  • the adaptive overcurrent protection proposed by the invention completes the fast and accurate isolation of the fault by detecting the information of each point in real time, adjusting the protection setting value and optimizing the fault condition of the action time limit.
  • This new type of protection based on fiber-optic communication and automatic control technology has significant advantages, but it has significant advantages, especially for regions and industries with high power requirements and abundant clean power resources.

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Abstract

一种微网自适应过流保护方法，包括以下步骤：1、在微网结构中配置中央保护单元，在各个断路器处配置就地保护单元，各个就地保护单元之间以及就地保护单元与中央保护单元之间通过光纤通信；2、在各个就地保护单元处配置自适应电流保护；3、中央保护单元实时收集就地保护单元上传的系统运行信息，确定微网运行模式、故障类型及故障点位置；4、并网运行模式下，就地保护单元对母线电压与馈线电流进行实时采样，然后根据采样值确定系统阻抗；孤岛运行模式下，就地保护单元根据故障类型计算自适应电流速断整定值；5、中央保护单元对实测电流值与整定值进行比较，确定故障隔离与供电恢复。该方法有利于对微网进行自适应过流保护。

Description

一种微网自适应过流保护方法 技术领域
本发明涉及微网保护技术领域，特别是一种微网自适应过流保护方法。
背景技术
微网作为一种新型电力技术，通过构建小型或微型低压配电系统，为太阳能、风能、生物质能等可再生能源以及天然气、氢气等环境友好型能源的综合利用提供了一种有效的技术手段。但同时，微网多变的运行模式及系统信息采集的复杂性对微网的保护控制带来了严峻的挑战。
微网既可并网运行又可孤岛运行，此外DG的投退和出力都具有随机性，导致微网并网运行时，部分负荷受其波动性影响，故障时其短路电流大小和方向都存在不确定性，从而很大程度上影响了保护的选择性和灵敏性。因此，微网的保护整定变得异常复杂。微网孤岛运行模式下内部发生故障时，逆变型DG受电力电子器件过流能力的限制，提供的短路电流值有限，导致传统过流保护因故障电流偏小或整定值过高而无法正常启动。针对微网运行出现的这些问题，近年来国内外学者开展了相关研究，并陆续提出了一些解决措施。一些文献提出在微网中应用导纳继电器设定整定判据进行保护，但并未深入分析验证。一些文献提出采用数字继电器进行微网保护，它能够检测过/欠电压、过电流并能编程来实现相互通信，但是不能做到实时反映系统运行状态，以最优的保护方式来解决故障问题。还有一些文献提出将微电网进行分区保护，故障时只将故障区隔离的方式，但此种保护方式降低了用电可靠性，不能保证整体系统的稳定性。微网并入大电网后，将从根本上改变大电网的网架结构，而且故障后的电气量特征发生显著变化，从而传统的故障检测和继电保护模式难以满足现行电网安全运行的要求。
发明内容
本发明的目的在于提供一种微网自适应过流保护方法，该方法有利于对微网进行自适应过流保护。
为实现上述目的，本发明的技术方案是：一种微网自适应过流保护方法，包括以下步骤：
步骤S1：在微网结构中配置中央保护单元，在各个断路器处配置就地保护单元，各个就地保护单元之间以及就地保护单元与中央保护单元之间通过光纤通信；
步骤S2：在各个就地保护单元处配置自适应电流保护；
步骤S3：中央保护单元实时收集就地保护单元上传的系统运行信息，确定微网运行模式、故障类型及故障点位置；
步骤S4：并网运行模式下，就地保护单元对母线电压与馈线电流进行实时采样，然后根据采样值确定系统阻抗；孤岛运行模式下，就地保护单元根据故障类型计算自适应电流速断整定值；
步骤S5：中央保护单元对实测电流值与整定值进行比较，确定故障隔离与供电恢复。
进一步的，所述中央保护单元为主控制器，用于收集、分析、处理、反馈信息以及下发控制指令，所述就地保护单元为从控制器，用于采集本地电气量信息和断路器位置信息。
进一步的，所述中央保护单元内含专门的自适应元件以实时更新保护定值；故障发生时，各个就地保护单元将故障信息上传至中央保护单元；中央保护单元整合分析包括电压降落、电流值大小、方向性判别的上传信息，以确定微网运行模式、故障类型及故障点位置。
进一步的，在步骤S5中，比较实测电流值与整定值，确定故障隔离与供电恢复，包括以下步骤：
步骤S501：确定实测电流Im；
步骤S502：确定相应馈线保护的各段整定值II set；
步骤S503：比较实测电流Im与相应馈线保护的各段整定值II set的大小；
步骤S504：对相应的就地保护单元发出动作指令，确定故障隔离与供电恢复。
本发明的有益效果是提出了一种新型的微网自适应过流保护方法，克服了现有技术存在的问题，有利于实现对微网的自适应过流保护，这种在全线安装断路器，利用网内节点信息，采用自适应技术的新型保护方式尤其适用对电能质量要求较高的地区。
附图说明
图1是本发明微网自适应过流保护方法的实现流程图。
图2是本发明实施例中自适应电流速断保护的实现流程图。
图3是本发明实施例中微网拓扑结构示意图。
图4是本发明实施例中自适应保护系统通信图。
图5是本发明实施例中双重故障下微网示意图。
图6是本发明实施例中孤岛模式下故障示意图。
具体实施方式
本发明微网自适应过流保护方法，如图1所示，包括以下步骤：
步骤S1：在微网结构中配置中央保护单元，在各个断路器处配置就地保护单元，各个就地保护单元之间以及就地保护单元与中央保护单元之间通过光纤通信。所述中央保护单元为主控制器，用于收集、分析、处理、反馈信息以及下发控制指令，所述就地保护单元为从控制器，用于采集本地电气量信息和断路器位置信息。
步骤S2：在各个就地保护单元处配置自适应电流保护。其按如下方法进行自适应电流保护：
1)自适应电流速断保护
传统电流保护速断定值是按最大运行方式下，躲开下一条馈线出口三相短路时流过保护的电流整定。事实上，短路电流的大小与系统运行方式、短路类型和短路点在线路上的位置都有关系。设在线路αZl处短路，则短路电流If为：
Figure PCTCN2015075752-appb-000001
式中，Kd为故障类型系数，三相短路时取1，两相短路时取
Figure PCTCN2015075752-appb-000002
Figure PCTCN2015075752-appb-000003
为系统等效电源的电势；ZS为保护安装处到系统等效电源之间的阻抗；α为比例系数，0≤α≤1；Zl为被保护馈线的阻抗。
因为式(1)中含有系统等效阻抗ZS，保护整定值受ZS变化的影响，所以发生故障时，自适应保护应能根据系统阻抗计算保护区末端的三相短路电流。但是当系统发生两相短路时，实际保护范围将缩小。因此，当发生故障时，应首先判定出故障类型，若为三相短路，则按保护区末端三相短路电流整定，若为两相短路，则按保护区末端两相短路电流值来整定，由此可大大提高保护的灵敏度。自适应保护的判据为：
Figure PCTCN2015075752-appb-000004
式中：Im为保护实测电流；II set为保护装置实时计算出的速断定值；
自适应速断保护的实现流程如图2所示。中央保护单元利用全网信息以判断系统运行模式，若并网运行，则通过分析馈线电压、电流的实时采样值计算出系统阻抗，然后计算各就地保护单元处的速断电流定值，通过将实测电流与整定值比较即可做出保护动作与否的判别。若微网孤岛运行，则中央保护单元直接计算孤岛运行时各就地保护单元的速断电流定值，通过比较实测电流与整定值大小关系，做出保护动作与否的判据。
2)自适应限时电流速断保护
自适应限时电流速断保护整定公式为：
III set＝KrelII set  (3)
tII 2＝tI 1+Δt  (4)
式中，II set和tI 1分别为下一条线路的自适应电流速断保护定值和整定时限；III set和tII 2分别为本线路自适应限时电流速断保护定值和整定时限；Δt为保证选择性而设定的延时，取0.05s。
该段保护的实现需要中央保护单元在求出速断电流定值的同时，给出限时速断定值。在预定时间内当保护I段拒动，而实测电流值超过II段定值时根据中央单元的指令，由保护II段切除故障。
3)自适应定时限过流保护
自适应定时限过流保护整定值如式(5)所示：
Figure PCTCN2015075752-appb-000005
式中，IIII set为本线路自适应过流保护电流整定值；Kre为继电器返回系数；Kss为自启动系数；Krel为可靠系数；Il为线路实际负荷。
该段保护的实现需要中央保护单元在求出速断电流和限时速断电流定值的同时，给出定时限过流保护整定值。当预定时间内保护I段和II段不动作时，根据中央单元的指令，由三段保护切除相应故障。
与传统保护相比，本发明微网自适应电流保护首先识别微网运行模式，并据此实时调整定值以应对不同类型的故障。该保护原理的优点是始终保证对被保护馈线进行保护，避免因故障类型、系统运行方式等造成的保护范围缩减甚至无保护范围问题。
步骤S3：中央保护单元实时收集就地保护单元上传的系统运行信息，确定微网运行模式、故障类型及故障点位置。
所述中央保护单元内含专门的自适应元件以实时更新保护定值；故障发生时，各个就地保护单元将故障信息上传至中央保护单元；中央保护单元整合分析包括电压降落、电流值大小、方向性判别的上传信息，以确定微网运行模式、故障类型及故障点位置。
中央保护单元实时收集就地保护单元上传的系统运行信息，其步骤为：1)每个就地保护单元负责采集本地电气量信息和断路器位置信息；2)就地保护单元将电气量信息和断路器位置信息上传至中央保护单元；3)中央保护单元作为整个通信系统的中枢，收集、分析就地保护单元上传的信息并处理、反馈、下发指令给就地保护单元。两者进行信息交互等确定微网运行模式、故障类型及确定故障点位置。
步骤S4：并网运行模式下，就地保护单元对母线电压与馈线电流进行实时采样，然后根据采样值确定系统阻抗，即计算ZS的值；孤岛运行模式下，就地保护单元根据故障类型计算自适应电流速断整定值，即计算
Figure PCTCN2015075752-appb-000006
的大小。
步骤S5：中央保护单元对实测电流值与整定值进行比较，确定故障隔离与供电恢复。具体包括以下步骤：
步骤S501：确定实测电流Im；
步骤S502：确定相应馈线保护的各段整定值II set；
步骤S503：比较实测电流Im与相应馈线保护的各段整定值II set的大小；
步骤S504：对相应的就地保护单元发出动作指令，确定故障隔离与供电恢复。
下面结合附图及具体实施例对本发明作进一步的详细说明。
图3是一种典型的微网拓扑结构示意图，其中CB和开关编号均表示断路器；G表示分布式电源；L表示负荷；T表示联络开关；F1～F4是故障点。图4是自适应保护系统通信图，其中红色虚线代表通信光纤。
微网自适应保护的动作时限整定优化：
①并网模式下自适应保护的时限整定：
如图3所示，在正常运行时，联络开关T断开，馈线1和2独立运行。若F4点发生故障，在F4上游的各CB均能检测到很大的短路电流，根据传统电流保护的整定分析，馈线1的各断路器时限整定情况如表1所示，表中1代表闭合，0代表断开。
表1传统保护的动作时限
Figure PCTCN2015075752-appb-000007
由表1可知，传统的时限动作方案存在弊端，其一，保护未安装方向元件无法应对微网内部双向潮流的特性，从而造成保护的选择性原则失效；其二，CB3.2和CB6.2的优先动作不符合保护切除故障的速动性要求；其三，CB2.1的定值整定过高，而DG提供的短路电流值较低，不足以启动保护。
对此，所提的自适应方向过流保护对时限定值进行了调整，尤其合理地优化了时限配合。表2是针对F4点故障时的自适应保护动作时限。由表2可知，这种时限动作既保证了故障的快速切除又保障了非故障区的正常供电。
表2自适应保护的动作时限
Figure PCTCN2015075752-appb-000008
联络开关闭合后，微网内部一旦再次故障，就需要重新调整定值和动作时限，以正确定位故障位置。如图5所示，当F4故障后断路器1.2和2.1断开，且联络开关闭合后微网内又出现F2点故障，表3给出了调整后的动作时限定值。
表3双重故障时的动作时限
Figure PCTCN2015075752-appb-000009
由表3可知，微网故障重构后，中央保护单元重新调整的动作时限定值表保证了再次故障时保护的快速性。
微网独特的内部结构决定了潮流的双向性和故障电流的双向性，故障电流的顺、逆时针流向决定了保护整定方案的双向备选。如图3，若微网正常运行时T闭合，而F4突然故障为例，给出双向方案的动作时限。表中动作时限的确定考虑了DG容量、方向性等因素综合确定。
②孤岛模式下自适应保护的时限整定：
孤岛模式下的故障电流存在双向可能性，此时的故障电流值约为额定电流的2倍。根据孤岛区域内多点信息的反馈，尤其是DG运行状态、故障电流大小和方向、电压降落情况来实时调整定值是保证敏感负荷正常供电的重要一环。如图6所示，G2的助增电流使得CB3.2和CB6.2的故障电流偏小，甚至低于保护定值，而且故障点附近电压降落幅值很大。为避免出现保护误动和拒动现象，可依据临近CB的故障电流方向性来确定故障点大致位置，以表4中提到的顺时针方向为正方向，根据流经CB2.2和CB3.1的故障电流方向相反这一事实，定位出故障点F4。
表4双向方案的动作时限定值
Figure PCTCN2015075752-appb-000010
综上，要实现微网自适应过流保护需满足以下要求：①在线监测微网运行模式的 变化，主要通过CB信息和负荷电流信息反馈；②在线监测微网DG的数量、类型、以及状态，从而为自适应保护的整定值调整提供依据，因为同步发电机提供的短路电流和逆变型电源贡献的短路电流大小差距明显；③在线检测方向元件信息以及电压、电流故障分量信息来确定故障类型，通过CB和负荷电流信息确定故障位置。
另外，并网模式下DG的投退及负荷的投切可能造成潮流由微网侧流向系统侧，这一点不会影响保护系统的正常工作，因为中央保护单元及通信系统的实时监测调整以及保护的方向定值设置可满足其正常工作的要求。
本发明提出的自适应过流保护通过实时检测各点信息、调整保护定值和优化动作时限反应不同的故障情况，完成对故障的快速准确隔离。这种基于光纤通信和自动控制技术的新型保护虽然投资较大，但是其具有显著的优越性，尤其适用于供电要求较高以及清洁发电资源丰富的地区和行业。
以上是本发明的较佳实施例，凡依本发明技术方案所作的改变，所产生的功能作用未超出本发明技术方案的范围时，均属于本发明的保护范围。

Claims (4)

  1. 一种微网自适应过流保护方法，其特征在于，包括以下步骤：
    步骤S1：在微网结构中配置中央保护单元，在各个断路器处配置就地保护单元，各个就地保护单元之间以及就地保护单元与中央保护单元之间通过光纤通信；
    步骤S2：在各个就地保护单元处配置自适应电流保护；
    步骤S3：中央保护单元实时收集就地保护单元上传的系统运行信息，确定微网运行模式、故障类型及故障点位置；
    步骤S4：并网运行模式下，就地保护单元对母线电压与馈线电流进行实时采样，然后根据采样值确定系统阻抗；孤岛运行模式下，就地保护单元根据故障类型计算自适应电流速断整定值；
    步骤S5：中央保护单元对实测电流值与整定值进行比较，确定故障隔离与供电恢复。
  2. 根据权利要求1所述的一种微网自适应过流保护方法，其特征在于，所述中央保护单元为主控制器，用于收集、分析、处理、反馈信息以及下发控制指令，所述就地保护单元为从控制器，用于采集本地电气量信息和断路器位置信息。
  3. 根据权利要求1所述的一种微网自适应过流保护方法，其特征在于，所述中央保护单元内含专门的自适应元件以实时更新保护定值；故障发生时，各个就地保护单元将故障信息上传至中央保护单元；中央保护单元整合分析包括电压降落、电流值大小、方向性判别的上传信息，以确定微网运行模式、故障类型及故障点位置。
  4. 根据权利要求1所述的一种微网自适应过流保护方法，其特征在于，在步骤S5中，比较实测电流值与整定值，确定故障隔离与供电恢复，包括以下步骤：
    步骤S501：确定实测电流Im；
    步骤S502：确定相应馈线保护的各段整定值II set；
    步骤S503：比较实测电流Im与相应馈线保护的各段整定值II set的大小；
    步骤S504：对相应的就地保护单元发出动作指令，确定故障隔离与供电恢复。
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Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20020101695A1 (en) * 2001-01-26 2002-08-01 Saksa Thomas A. Adaptive power circuit protection apparatus and method
CN101515715A (zh) * 2009-04-03 2009-08-26 天津大学 基于广域网的含分布式电源馈线保护方法
CN102255290A (zh) * 2011-06-27 2011-11-23 华北电力大学 一种电流自适应保护方法
CN102570617A (zh) * 2012-02-17 2012-07-11 黑龙江省电力有限公司 一种在多个变电站之间实现广域保护系统的方法
CN103956717A (zh) * 2014-05-27 2014-07-30 国家电网公司 一种微网自适应过流保护方法

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR101097458B1 (ko) * 2009-11-09 2011-12-23 한국전기연구원 마이크로그리드 시스템 및 정지형 스위치의 부하제어 방법
CN101714756B (zh) * 2009-12-16 2011-12-28 北京四方继保自动化股份有限公司 一种基于等效负序阻抗的分布式电源孤岛保护方法
CN102420428A (zh) * 2011-12-19 2012-04-18 天津市电力公司 一种用于对微网能量进行管理的方法及系统
CN103199529A (zh) * 2013-04-22 2013-07-10 南京四方亿能电力自动化有限公司 基于iec61850标准的微网综合协调控制架构

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20020101695A1 (en) * 2001-01-26 2002-08-01 Saksa Thomas A. Adaptive power circuit protection apparatus and method
CN101515715A (zh) * 2009-04-03 2009-08-26 天津大学 基于广域网的含分布式电源馈线保护方法
CN102255290A (zh) * 2011-06-27 2011-11-23 华北电力大学 一种电流自适应保护方法
CN102570617A (zh) * 2012-02-17 2012-07-11 黑龙江省电力有限公司 一种在多个变电站之间实现广域保护系统的方法
CN103956717A (zh) * 2014-05-27 2014-07-30 国家电网公司 一种微网自适应过流保护方法

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
ZHANG, DI ET AL.: "Application and Research of Self-adaptive Protection in Micro-grid", SCIENCE TECHNOLOGY AND ENGINEERING, vol. 12, no. 35, 31 December 2012 (2012-12-31) *

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
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