A kind of protection system of the regional power grid data sharing based on IEC61850
Technical field
The invention belongs to relay protection of power system and safety control technology field, particularly a kind of based on the regional power grid electric parameters of IEC61850 and relaying protection and the safety control system and the method for quantity of state information sharing.
Background technology
The development of and electricity market interconnected along with electrical network, electric power system will be day by day near its operational limit, and its operation and control will more complicated, and the possibility that disturbance and fault take place is bigger, and consequence is also more serious, and this has higher requirement to stablizing to control.
Conventional relaying protection is used for breaking down the back realization to the automatic of fault element and excision, isolated fault fast in electric power system, to guarantee personal and device security and fault-free normal operation partly.Existing relaying protection and automatic safety device can not adapt to the requirement of power system development, and subject matter is as follows:
The protection operating criterion all is based on the local measurement data, and its selectivity requires relaying protection can only protect local network, does not consider the influence of fault to whole electrical network, is difficult to the objective system of the continuous variation of operational mode is made comprehensive reflection.Protective device lacks effective coordination each other, is difficult to the safe and stable operation of the realization system overall situation, in some cases the operation conditions of (as cascading failure takes place) meeting deterioration system.In high load capacity period, the through-put power on these crucial interconnections may be near the transmission power limit.The ability of Yun Hang system's disturbance rejection reduces greatly in this case, is easy to cause all the other circuit overloads and disconnection in succession because an interconnection generation contingent disconnects, thereby accident is spread, even cause system crash.The U.S. 8.14 accident of having a power failure on a large scale disconnects in succession from several circuits at first.
Though conventional backup protection has bigger protection range, it optionally obtains will be cost to sacrifice rapidity, and operate time is long, sometimes is difficult to bring into play due protective effect.In the middle of the existing relaying protection configuration, the time limit setting of backup protection is followed the ladder principle of timeliness, and in order to guarantee selectivity, the operation time limit of backup protection may be up to the several seconds.Under the increasing situation of scale of power and complexity, this problem is apparent more outstanding, still can't well solve so far.
The main effect of automatic safety device is a safe and stable operation of safeguarding electrical network, in case of emergency takes modes such as load shedding, cutter and system splitting operation to avoid mains breakdown and cause the accident of having a power failure on a large scale.The automatic safety device of electric power system at present and protective relaying device are two to overlap independently system, lack effectively communication between the two and cooperate, and can't accurately reflect the situation of change of whole system.
Along with laying in a large number of computer and network development of Communication Technique, particularly optical fiber, provide necessary information basis for obtaining regional power grid multiple spot electric parameters and quantity of state information.Simultaneously, along with the enhancing of computer process ability,, relaying protection system and automated security control system provide hardware condition for being integrated.The IEC61850 standard is the electric substation automation system standard of International Electrotechnical Commission (IEC) issue.China from the research on standard step transition to the engineering application stage, and existing a plurality of transformer stations based on the IEC61850 standard come into operation.The IEC61850 standard has been represented the developing direction of automation of transformation substations technology.
After adopting the IEC61850 standard, all information of transformer station can be transmitted and share by network, make protective relaying device can obtain more information, thereby be the condition of application creation necessity of novel Principles of Relay Protection.But clear and definite technical scheme is not arranged as yet under the IEC61850 standards system, how making up relaying protection system.Traditional relaying protection system is towards force device, such as route protection, tranformer protection, bus protection, generator protection, motor protection or the like.Lack effective information communication and information sharing between each protection equipment, make traditional relaying protection system usually attend to one thing and lose sight of another, be difficult to satisfy the requirement of growing electric power system.Regional intelligent protection based on the datumization information of the digital transformer substation of regional power grid the inside is the developing direction of following Protection Technology.
Summary of the invention
The present invention proposes a kind of based on the regional power grid electric parameters of IEC61850 and the protection control system of quantity of state information sharing.This system can finish route protection, failure protection function and UFLS, the low pressure Load Alleviation Function of regional power grid.
For achieving the above object, the present invention adopts following technical scheme:
A kind of protection system of the regional power grid data sharing based on IEC61850, this system is that transformer station and power plant are formed by several websites, communicates by fiber optic Ethernet between each website, carries out data acquisition synchronously, shares image data; It is characterized in that,
The process bus of system is made of fiber optic Ethernet in the station of each website, is used for the data communication between merge cells, intelligent operation box and the intelligent protection device;
Merge cells is realized the synchro measure to line voltage, electric current and switching value, and measurement data is sent on the process bus;
The GPS time service device carries out time service to all merge cells and the intelligent operation boxes of system in standing, and guarantees that intelligent protection device obtains the switching value information that analog quantity information (being the synchro measure data message) that merge cells send and intelligent operation box send from process bus and all has the GPS synchronous time mark;
Intelligent protection device calculates line voltage, the amplitude of electric current, phase place, the frequency information in this website, by described fiber optic Ethernet amplitude, phase place and the frequency information of the line voltage in this website that is calculated, electric current and the quantity of state data that measure is sent to other websites together with calculating gps time information constantly; Intelligent protection device calculates and analyzes to judge whether protected electrical network unusual and fault have taken place according to this station data and the information data of other websites of sharing, and then according to the result of judgement and the integrated information generation control commands corresponding of electrical network, assign to corresponding intelligent operation box by network, guarantee the rapid and reliable excision fault of this protection system; The data that the while real-time storage is collected, and write down and assign to the various command of intelligent operation box and other information of sending, prepare against query analysis in the future.
The sample rate of the merge cells of system is ripple 80 points weekly in the described station, the communication protocol of sampling is IEC61850-9-2 (particular communication service mapping (SCSM) is by the sampled value standard of ISO/IEC 8802-3), by this agreement, merge cells sends to the analog quantity information that collects on the process bus.
Communication protocol in the described station between the intelligent operation box of system and the protection main frame is GOOSE (towards the transformer substation case of general object), and all information that configure (as tripping operation, interlocking, circuit-breaker status) can be transmitted on process bus; Intelligent operation box A and intelligent operation box B are the identical devices of function, and any device receives that the trip signal of protection main frame can go to carry out corresponding trip operation.
The intelligent protection main frame of system and intelligent protection slave can be according to the dualization configurations of domestic relaying protection standard-required in the described station; intelligent protection main frame and slave detect fault arbitrarily; can send trip signal apace, guarantee that transforming plant integrated protection system can rapid and reliable excision fault.
The present invention is based on the control system and the control method of regional power grid electric parameters and quantity of state information sharing, and it judges comprehensively whether electric power system fault and unusual has taken place.Adopt the backup protection of differential current, avoided traditional line backup protection to adopt long problem of distance protection setting difficulty and operate time as circuit.Behind certain bar line tripping, improve the overload definite value of the All other routes of same power section automatically, solved the difficult problem of the insurmountable cascading trip of traditional relay protection.The present invention can obtain the voltage and the frequency situation of whole regional power grid, can take all factors into consideration whole topological structure of electric, selects optimum cutting load mode, thereby recovers power grid operation as soon as possible.Under the situation of switch tripping, the present invention can send trip signal for fast the switch of tripping switch adjacent node, avoids the expansion of accident.Can promote the effect of relaying protection and automatic safety device significantly, guarantee the safe and stable operation of electrical network.
Description of drawings
Figure 1 shows that the protection system structural representation of regional power grid data sharing of the present invention;
Figure 2 shows that system configuration structure chart in the transformer station station.
Embodiment
According to Figure of description technical scheme of the present invention is made further detailed presentations below.
Regional power grid data sharing protection system based on IEC61850 of the present invention is made up of some websites, communicates by network between each website, and the whole system structure as shown in Figure 1.Regional power grid by several websites, be that transformer station and power plant are formed, communicate by network between each website, share image data.Intelligent protection device has data acquisition module; utilize the synchro measure of gps satellite synchronised clock realization to line voltage, electric current and quantity of state; and calculate line voltage, the amplitude of electric current, phase place, frequency information, by described network the line voltage that is calculated, amplitude, phase place and the frequency information of electric current and the quantity of state data that measure are sent to other websites together with calculating gps time information constantly.
Figure 2 shows that system configuration structure chart in the transformer station station, the process bus of system is made of fiber optic Ethernet in the described station, is used for the data communication between merge cells, intelligent operation box and the intelligent protection.The GPS time service device carries out time service to merge cellses all in the transformer station and intelligent operation box, guarantees that analog quantity and switching value that intelligent protection is obtained all have the GPS synchronous time mark.Intelligence main protection and intelligent backup protection are obtained the switching value information that analog quantity information that merge cells send and intelligent operation box send from process bus.
In the regional power grid between each website the special data channel of the 2M bandwidth by electric power system communicate.The process bus of system is made of fiber optic Ethernet in standing, and is used for the data communication between merge cells, intelligent operation box and the intelligent protection.The GPS time service device carries out time service to merge cellses all in the transformer station and intelligent operation box, guarantees that analog quantity and switching value that intelligent protection is obtained all have the GPS synchronous time mark.Intelligence main protection and intelligent backup protection are obtained the switching value information that analog quantity information that merge cells send and intelligent operation box send from process bus.
The sample rate of merge cells is ripple 80 points weekly, the communication protocol of sampling is IEC61850-9-2 (particular communication service mapping (SCSM) is by the sampled value standard of ISO/IEC 8802-3), by this agreement, merge cells sends to the analog quantity information that collects on the process bus.
Communication protocol between intelligent operation box and the protection main frame is GOOSE (towards the transformer substation case of general object), and all information that configure (as tripping operation, interlocking, circuit-breaker status) can be transmitted on process bus; Intelligent operation box A and intelligent operation box B are the identical devices of function, and any device receives that the trip signal of protection main frame can go to carry out corresponding trip operation.
The intelligent protection main frame of system and intelligent protection slave can be according to the dualization configurations of domestic relaying protection standard-required in the described station; intelligent protection main frame and slave detect fault arbitrarily; can send trip signal apace, guarantee that transforming plant integrated protection system can rapid and reliable excision fault.
Intelligent protection device is installed in the transformer station of protected regional power grid, merge cells utilizes the synchro measure of high accurate GPS satellite synchronizing clock realization to line voltage, electric current and quantity of state, and calculate line voltage, the amplitude of electric current, phase place, frequency information, by network the line voltage that is calculated, amplitude, phase place and the frequency information of electric current and the quantity of state data that measure are sent to other websites together with calculating gps time information constantly; Intelligent protection device calculates and analyzes to judge whether protected electrical network unusual and fault have taken place according to this machine data and the information data of other websites of sharing, and then, assign to corresponding intelligent final controlling element by network according to the result of judgement and the integrated information generation control commands corresponding of electrical network; The data that the while real-time storage is collected, and write down and assign to the various command of intelligent final controlling element and other information of sending, prepare against query analysis in the future.
Intelligent protection device carries out phasor calculation one time every 10ms, calculates amplitude and the phase place and the frequency of voltage, electric current with Fourier algorithm according to the sampled value of voltage, electric current.And quantity of states such as amplitude, phase place and frequency computation part result and circuit breaker position, disconnecting link positions together with calculating gps time information constantly is sent to other websites by network intelligent protection device.
Intelligent operation box by power insert, telecommunication management plug-in unit, leave plug-in unit, open into plug-in unit and form.Switching value is gathered in opening into plug-in unit of intelligence final controlling element, comprises circuit breaker breaker tripping and closing position, the disconnecting link position.Intelligent operation box leave the closing loop that plug-in unit is linked into the electric power system circuit breaker, to realize breaker tripping and closing operation to circuit breaker.The GOOSE information that the intelligence final controlling element is assigned by network reception intelligent protection device comprises tripping operation, the order etc. of closing a floodgate; and give intelligent protection device execution result by network-feedback; simultaneously the form of the GOOSE order of receiving with message stored in the intelligent final controlling element, in order to inquiry in the future.
Protection of the present invention and controlled function comprise following logic function and step, and each functional module is separate, can throw by control word and move back.
As route protection, judge at first whether the current mutation component of each side of circuit starts, there is not fault if be not activated explanation, if sudden change amount element starts, intelligent protection adopts traditional differential protecting technology to carry out fault verification.For the circuit with branch, the end that the system of distance power supply is nearest is done the electric current of other branch phasor and is calculated as an other side as a side.The phasor of both sides electric current and amplitude as differential current, the amplitude of both sides electric current phasor difference is as stalling current, adopts ratio-restrained characteristic to judge.When current transformer circuit supervision fail takes place when, can be according to the setting of control word Blocking Differential Protection whether.
Adaptive overload protection function.When certain bar circuit causes this circuit out of service because of overload or fault, may cause the All other routes on the same power section out of service, thereby cascading failure occur because of the overload tripping operation.For avoiding the generation of cascading failure; intelligent protection device is behind certain bar line tripping; automatically improve the overload current ration and the time definite value of the All other routes of same power section, reduce overload protection overladen sensitivity in the case, thereby avoid the cascading trip accident.
Low frequency, low pressure cutting load function.When system's occurrence frequency is lower than predetermined value or voltage and is lower than predetermined value (this predetermined value is that the dispatching of power netwoks operations staff sets in advance), cut-out is loaded to prevent voltage collapse and frequency collapse.Intelligent protection device can obtain the state information of voltage, electric current, frequency and the switching value of whole each node of electrical network.Different with traditional cutting load strategy, the preferred following cutting load strategy of intelligent protection device of the present invention: voltage and the frequency of at first calculating each node bus of electrical network, for the protection of low pressure off-load, select the minimum bus of voltage, then the minimum circuit of excision load class on this bus; Again adjust the voltage of all buses in the electrical network, select the minimum bus of voltage once more, excise the minimum circuit of load class on this bus; Repeat above step, return to allowed band up to system voltage.
For UFLS, select the minimum bus of frequency, then the minimum circuit of excision load class on this bus; Again adjust the frequency of all buses in the electrical network, select the minimum bus of frequency once more, excise the minimum circuit of load class on this bus; Repeat above step, return to allowed band up to system frequency.
When intelligent protection device detects and determines line failure; send out tripping operation by network to corresponding substation control execution unit and make each side circuit breaker of tripping faulty line; after setting time-delay; if faulty line also has electric current; then think this breaker failure; then send out to corresponding substation control execution unit and jump the circuit breaker that makes this faulty line upper level of tripping, avoid the further expansion of accident by network.