CN107332217B - The co-architecture and Synergistic method of the power distribution protection of the device containing flexible interconnection - Google Patents

The co-architecture and Synergistic method of the power distribution protection of the device containing flexible interconnection Download PDF

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Publication number
CN107332217B
CN107332217B CN201710679048.3A CN201710679048A CN107332217B CN 107332217 B CN107332217 B CN 107332217B CN 201710679048 A CN201710679048 A CN 201710679048A CN 107332217 B CN107332217 B CN 107332217B
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protection
flexible interconnection
intelligent
network
direct current
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CN107332217A (en
Inventor
郑舒
赵景涛
孙国城
蔡月明
徐志华
陈平
李蕴
黄仁乐
常乾坤
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State Grid Beijing Electric Power Co Ltd
Nari Technology Co Ltd
NARI Nanjing Control System Co Ltd
Nanjing NARI Group Corp
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State Grid Beijing Electric Power Co Ltd
Nari Technology Co Ltd
NARI Nanjing Control System Co Ltd
Nanjing NARI Group Corp
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    • HELECTRICITY
    • H02GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02HEMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
    • H02H7/00Emergency 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
    • H02H7/26Sectionalised protection of cable or line systems, e.g. for disconnecting a section on which a short-circuit, earth fault, or arc discharge has occured

Abstract

The invention discloses co-architecture, device and the Synergistic methods of a kind of power distribution protection of device containing flexible interconnection; under the frame of Collaborative Control; the quick positioning and failure removal for making full use of the fast state of the power electronic devices of alternating current-direct current flexible interconnection device to perceive and exchange side protection for feed line control device realization failure, to realize the area fault quickly autonomous self-healing of full ac and dc systems;It proposes through the GOOSE communication network based on the interaction of region high speed information; fast failure positioning, the isolation of protective device are realized in the global information high-speed communication for realizing the intelligent apparatus in same ac and dc systems including flexible direct current interconnect device according to preset condition automatically.Relative to the relaying configuration mode of conventional electrical distribution system, there is faster troubleshooting speed and preferably collaboration troubleshooting capability, to have very high application value.

Description

The co-architecture and Synergistic method of the power distribution protection of the device containing flexible interconnection
Technical field
The present invention relates to the co-architectures and Synergistic method of a kind of power distribution protection of device containing flexible interconnection, belong to power train System and its field of automation technology.
Background technique
Research achievement in recent years shows that the alternating current-direct current mixing power distribution network based on flexible direct current technology is more suitable for modern city The development of power distribution network.Alternating current-direct current mixing power distribution network can preferably receive distributed generation resource and DC load, can be relieved urban distribution network Website corridor is limited with the high contradiction of load density, while providing dynamic reactive in load center and supporting, system safety can be improved Maintenance level simultaneously reduces loss.Therefore, alternating current-direct current mixing power distribution network is an important trend of power distribution network, can effectively be mentioned Rise power quality, reliability and the operational efficiency of city electric distribution system.Currently, for the event of flexible interconnection device access power distribution network Hinder feature and protection and control technology, lay particular emphasis on DC side protection, including protection of direct current supply line, converter station internal unit is protected The research such as shield.
When pressing the engineering of alternating current-direct current power distribution network in Utilities Electric Co. both domestic and external construction, mainly for AC system distribution from The research and construction of dynamicization, distribution terminal, but for the prepared protection of ac and dc systems feature of flexible interconnection device access Implementation method is related to less.If using traditional distributing protection supervisory equipment, what each protection supervisory equipment can obtain System information is limited, can not cooperate with flexible interconnection device and make quick judgement, also just can not be to the event of entire ac and dc systems Barrier, which is made, quickly and accurately to be judged.There is R&D institution to propose using centralized decision-making mode, increases in Ac/dc Power Systems Master controller is protected, by protecting master controller to acquire the protection act information of full ac and dc systems, including flexible interconnection device Action message, system-wide wide area protection is realized with this, realizes fault location and isolation;But this protection form wants communication Ask very high, protection master controller requires to obtain the protection supervisory equipment status information of whole station, and acquisition signal speed is slow, logic judgment Complexity, judgement will also issue outlet order after being out of order to related protection supervisory equipment, and speed is slow, and safety can not obtain Meet well.
Summary of the invention
To solve the deficiencies in the prior art, the purpose of the present invention is to provide a kind of flexible interconnection devices protects on the spot with exchanging Co-architecture, device and the Synergistic method for protecting control device have faster relative to the relaying configuration mode of conventional electrical distribution system Troubleshooting speed and preferably collaboration troubleshooting capability, thus have very high application value.
In order to achieve the above objectives, the present invention adopts the following technical scheme that:
A kind of co-architecture of the power distribution protection of the device containing flexible interconnection, characterized in that including in flexible interconnection device Both ends MMC current changer module status information interaction and Collaborative Control, flexible interconnection device two sides fault in ac transmission system status information Interactive and Collaborative Control, MMC current changer module and the information exchange and Collaborative Control for exchanging side protection for feed line control device.
A kind of power distribution protective device of the device containing flexible interconnection, characterized in that one by one including breaker, with the breaker Corresponding protection supervisory equipment, flexible interconnection device and interchanger;The interchanger with intelligent apparatus for being connected.
Further, every intelligent apparatus includes two network interfaces, is denoted as A network interface and B network interface respectively, wherein A network interface It connects interchanger, be connected with monitoring, B network interface connects the B network interface of adjacent intelligent apparatus, realizes that network is shaken hands.
Further, between the intelligent apparatus use 61850 communication standards, by GOOSE mechanism realize each unit it Between high speed data exchange and mutually locking.
Further, using two neighboring or three or more the determined regions of breaker as unit, network tip portion is with end The downstream area that tip feeder breaker is divided is unit, and entire alternating current-direct current mixing power distribution network is divided into several Minimum Areas, Using each Minimum Area as an intelligent apparatus associated region;Intelligent apparatus in one protective device associated region is set It is one group, transmits signal in the way of multicast and broadcast between monitoring, and it is that highest preferentially transmits that remote signalling displacement signal, which is arranged, Grade;Monitoring carries out logic judgment to signal is received, and diagnoses fault simultaneously isolated fault region.
A kind of Synergistic method of the power distribution protection co-architecture of the device containing flexible interconnection, characterized in that
When metallicity three-phase fault occurs for flexible direct current interconnect device exchange exit, failure side MMC module is latched simultaneously Region communication network is transmitted, communication area intelligent apparatus receives the quick sensing signal of flexible interconnection device, realizes quickly event Phragma from;
When direct current system breaks down, flexible interconnection device two sides MMC module is latched and transmits to region communication network; Power electronic equipment is latched rapidly direct current region, guarantees that communication area failure is not passed through;Meanwhile the intelligent protection measuring of communication area Breakdown judge and isolation features that device is furnished with intelligent distributed FA are controlled, in the area that AC system and soft straight device are not connected with Domain guarantees the safety and stability of communication area using the criterion of distributed FA;
Exchange side protection for feed line control device receives whole district's signal, and quick discrimination fault section simultaneously acts.
Advantageous effects of the invention: making full use of the power electronic devices fast state of flexible direct current interconnect device The characteristics of perception, by establishing fast messaging network, the snap information interaction of all intelligent apparatus in realization ac and dc systems, In the case where without central control system, before the protection of single exchange side outlet detects fault point, position to fast accurate Non-faulting block supply is restored in region to greatest extent;It is fast with processing speed, at low cost, do not depend on the excellent of single control unit Point;Compared to the cooperation only considered between exchange side protective device, this method combination alternating current-direct current mixes the fault characteristic of distribution system, Using the fast response characteristic of IGBT, by the foundation of GOOSE high-speed communication network, failure detection time reduces more than half, Effectively enhance the alternating current-direct current mixing distribution network reliability of the device containing flexible interconnection, shortens power off time.
Detailed description of the invention
Fig. 1 is the schematic diagram of Collaborative Control framework of the present invention;
Fig. 2 is the schematic diagram of cooperative control method of the present invention.
Specific embodiment
The invention will be further described below in conjunction with the accompanying drawings.Following embodiment is only used for clearly illustrating the present invention Technical solution, and not intended to limit the protection scope of the present invention.
The technical solution adopted by the present invention is broadly divided into building flexible interconnection device and power distribution protection control device when being based on Sequence cooperation Collaborative Control framework, support realize exchange the quick treatment in situ of side failure based on, flexible direct current plant failure differentiate Supplemented by coordination control strategy, while guaranteeing in Ac/dc Power Systems that flexible interconnection device is filled with the control of side protection for feed line is exchanged The Collaborative Control based on time cooperation is set, the both ends MMC current changer module status information in flexible interconnection device is interacted and cooperateed with Control, the interaction of flexible interconnection device two sides fault in ac transmission system status information and Collaborative Control, MMC module are protected with side feeder line is exchanged Protect the contents such as information exchange and the Collaborative Control of control device.
Wherein, the flexible interconnection device based on time cooperation and power distribution protection control device Collaborative Control framework applications to dress In setting, the device as described in power 2 is formed:
Feeder line is exchanged with time cooperation control function with novel as shown in Figure 1, using distribution flexible interconnection device Protective device is based on distribution flexible interconnection device and the novel ac and dc systems Collaborative Control frame for exchanging feeder protection equipment Structure.Framework building exchanges feeder protection equipment with time cooperation control function with novel based on distribution flexible interconnection device Collaborative Control communication construction, alternating current-direct current mixing distribution protection control framework in include protecting survey correspondingly with breaker Control device, flexible interconnection device and an interchanger are communicated for the reliability of Ac/dc Power Systems network using dual network Structure, every intelligent apparatus all include two network interfaces, are denoted as A network interface and B network interface respectively, and wherein A network interface connects interchanger and monitoring It is connected, B network interface connects the B network interface of adjacent intelligent apparatus, realizes that network is shaken hands, 61850 communication standards are used between each intelligent apparatus, Using fast fibre network, the data exchange of high speed and mutually locking between each unit are realized by GOOSE mechanism.To the distribution In non-feeder line tip portion using two neighboring or three or more the determined regions of breaker as unit, network tip portion is with end The downstream area that tip feeder breaker is divided is unit, and entire alternating current-direct current mixing power distribution network is divided into several Minimum Areas, Using each Minimum Area as an intelligent apparatus associated region;Intelligent apparatus in one protective device associated region is set It is one group, transmits signal in the way of multicast and broadcast between monitoring, and it is that highest preferentially transmits that remote signalling displacement signal, which is arranged, Grade;Monitoring carries out logic judgment to signal is received, and diagnoses fault simultaneously isolated fault region.
Flexible direct current interconnect device and the content for the cooperative control method for exchanging in-situ protection control device are as follows:
Under the premise of guaranteeing Ac/dc Power Systems safety and stability, using based on time cooperation flexible interconnection device with Power distribution protection control device Collaborative Control framework, according to the quick sensing of direct current power electronic device Microsecond grade in ac and dc systems And responding ability, cooperate with AC system intelligent apparatus GOOSE rapid communication, is sent out in soft straight device and AC system connected regions When raw metallicity three-phase fault, communication area intelligent apparatus receives the quick sensing signal of flexible interconnection device, realizes quickly event Phragma from.When direct current region is broken down, power electronic equipment is latched rapidly direct current region, guarantees that communication area failure is not worn More.Meanwhile the Intelligent protection measuring controller of communication area is furnished with the breakdown judge and isolation features of intelligent distributed FA, is exchanging The region that system and soft straight device are not connected with guarantees the safety and stability of communication area using the criterion of distributed FA.
Specifically, coordination control strategy is as shown in Figure 2 when in use for this method:
In normal state, central control unit is in data acquisition and total system monitoring mode, direct current interconnecting electric power electricity Sub- intelligent cell and harmonics control unit normal communication carry out information exchange, and will send in data.Central control unit phase When controlling full ac and dc systems information in systematic steady state in scheduling sub-station, system is provided under complicated rack environment and is stablized Optimal control improves utilization rate of equipment and installations, improves direct current power electronic device power supply capacity.In addition, central control unit can shift to an earlier date It is communicated with distribution main website, according to the advanced applied analysis function of main website, operation plan is carried out in advance, according to Load flow calculation, network Analysis etc. as a result, carry out scheduling controlling strategy in advance, it is ensured that the stabilization of full alternating current-direct current distribution network systems, economical operation.
Under nonserviceabling, each intelligent apparatus in Ac/dc Power Systems carries out information friendship by the communication network of high speed Mutual and logic judgment, quickly makes the control on the spot of fault location and isolation, avoids the analysis of central control unit upper layer data And the delay of instruction issuing.The MMC current changer module at flexible direct current interconnect device both ends is exported in exchange occurs metallicity three-phase It can be given in rapid drawdown of the other time inner sense of Microsecond grade by voltage by the logic judgment built in flexible interconnection device when short-circuit Adjacent intelligent apparatus quickly transmits, and the protection control device in adjacent direct current exit receives the failure letter of flexible interconnection device Number, it transmits to the harmonics control device of next stage, makes Fault Isolation judgement and movement.Meanwhile direct current occurs for DC side When failure, flexible direct current interconnect device recognizes failure prior to exchange side protective device, is latched the MMC change of current of direct current system two sides Device, isolated DC failure prevent fault traversing, and with high speed fibre channel transmit to exchange side Intelligent protection measuring controller and The central control unit of upstream, it is ensured that protect not malfunction in exchange side.
Secondly, flexible direct current interconnect device is unaffected when the exchange side in non-inverting device exit is broken down, exchange The protection control device of side is differentiated using the distributed FA function of configuration and isolated fault, and central control unit is made to be exchange side Protection control device makes aid decision, the processing to abnormal conditions such as communication abnormality, switch failure, switch leapfrog jumps.
Advantageous effects of the invention: flexible interconnection device and power distribution protection control device based on time cooperation are assisted It lays the foundation on the physical structure of communication, on the seamless transitions of strategy with control, compared to only consideration exchange side protective device Between cooperation, this method combination alternating current-direct current mix distribution system fault characteristic, utilize the quick sound of flexible electric electronic device Characteristic is answered, by the foundation of GOOSE high-speed communication network, failure detection time reduces more than half, and effectively enhancing is containing flexibility The alternating current-direct current mixing distribution network reliability of interconnect device.
The above is only a preferred embodiment of the present invention, it is noted that for the ordinary skill people of the art For member, without departing from the technical principles of the invention, several improvement and deformations can also be made, these improvement and deformations Also it should be regarded as protection scope of the present invention.

Claims (4)

1. a kind of power distribution protection co-architecture of device containing flexible interconnection, characterized in that including the both ends in flexible interconnection device The interaction of MMC current changer module status information and Collaborative Control, the interaction of flexible interconnection device two sides fault in ac transmission system status information With Collaborative Control, MMC current changer module and the information exchange and Collaborative Control for exchanging side protection for feed line control device;Including open circuit Device and the one-to-one protection supervisory equipment of the breaker, flexible interconnection device and interchanger;The interchanger is used for and intelligence Energy device is connected;Using two neighboring or three or more the determined regions of breaker as unit, network tip portion is presented with tip The downstream area that line breaker is divided is unit, entire alternating current-direct current mixing power distribution network is divided into several Minimum Areas, with every One Minimum Area is as an intelligent apparatus associated region;Intelligent apparatus in one protective device associated region is set as one Signal is transmitted between group, with monitoring in the way of multicast and broadcast, and it is that highest preferentially transmits grade that remote signalling displacement signal, which is arranged,;Prison Control carries out logic judgment to signal is received, and diagnoses fault simultaneously isolated fault region.
2. the power distribution protection co-architecture of the device according to claim 1 containing flexible interconnection, characterized in that every intelligence Energy device includes two network interfaces, is denoted as A network interface and B network interface respectively, and wherein A network interface connects interchanger, is connected with monitoring, and B network interface connects The B network interface of adjacent intelligent apparatus realizes that network is shaken hands.
3. the power distribution protection co-architecture of the device according to claim 2 containing flexible interconnection, characterized in that the intelligence dress 61850 communication standards are used between setting, and the data exchange of high speed and mutually locking between each unit are realized by GOOSE mechanism.
4. a kind of Synergistic method of the power distribution protection co-architecture of the device according to claim 1 containing flexible interconnection, special Sign is,
When metallicity three-phase fault occurs for flexible direct current interconnect device exchange exit, failure side MMC module is latched and to area Domain communication network transmits, and communication area intelligent apparatus receives the quick sensing signal of flexible interconnection device, realize fast failure every From;
When direct current system breaks down, flexible interconnection device two sides MMC module is latched and transmits to region communication network;Electric power Electronic device is latched rapidly direct current region, guarantees that communication area failure is not passed through;Meanwhile the intelligent protection observing and controlling dress of communication area Breakdown judge and isolation features equipped with intelligent distributed FA are set, in the region that AC system and soft straight device are not connected with, is made Guarantee the safety and stability of communication area with the criterion of distributed FA;
Exchange side protection for feed line control device receives whole district's signal, and quick discrimination fault section simultaneously acts.
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