CN103823140B - Power network topology misidentification system and method thereof based on road-loop equation - Google Patents

Abstract

The invention discloses a kind of power network topology misidentification system and the method thereof based on road-loop equation in Power System Topology Analysis technical field. System comprises data acquisition module, branch current computing module, topology error identification module, bad data recognition module and result output module, data acquisition module, branch current computing module, topology error identification module, bad data recognition module and result output module are linked in sequence, and topology error identification module is connected with branch current computing module respectively with bad data recognition module; Method comprises: image data, ask for branch current calculated value, and identification power network topology mistake, in the time there is mistake in power network topology, more new data; Identification bad data, in the time there is bad data, revises relevant bad data; Finally export grid topology data and branch current measured value. The present invention is not subject to the impact of Topology Error and bad data double factor, has accuracy and the reliability of very high identification result.

Description

Power network topology misidentification system and method thereof based on road-loop equation

Technical field

The invention belongs to Power System Topology Analysis technical field, relate in particular to a kind of power network topology based on road-loop equationMisidentification system and method thereof.

Background technology

Power System Topology Analysis data are mainly made up of switching value, but in the process of switch acquisition, due to equipment or netThe reasons such as network, cause damage or the deviation of information unavoidably, cause topology information to occur mistake.

At present, Chinese scholars has proposed all multi-methods for power system topology error identification, as: residual error method, regular method,Minimum information loss method, hum pattern method, transfer trend method etc. But conventional method Data Source is comparatively single, the overwhelming majorityOnly, by supervisory control and data acquisition system (supervisorycontrolanddataacquisition, SCADA), switch is believedBreath carries out misidentification, and such data collection cycle is long and asynchronous, and double sampling value before and after needing toward contact, greatly reducesThe accuracy of topology error identification and rapidity. Meanwhile, cannot effectively identify at Topology Error and bad data and deposit in the situation that.

Along with the development of intelligent grid, synchronized phasor measurement technology and corresponding WAMS (Wide-Area thereofMeasurementSystem, WAMS) provide new technological means for Power System Topology Analysis. For this reason, this patent is by phaseThe synchronous electric tolerance information that provides of amount measuring unit (PhasorMeasurementUnit, PMU), proposed a kind of based on road-Topology error identification system and the method thereof of loop equation. First this invention utilizes topological constraints and the Kirchhoff's law of network,Road-loop equation of setting up, calculates branch current, on this basis, considers various Topology Errors and bad data the feelings of depositingCondition, carries out verification according to the difference between calculated value and measuring value to topology information and branch current measuring value. Based on IEEE3 machine 9Node system and IEEE10 machine 39 node system simulation results show, this invention is not subject to Topology Error and bad data double factorImpact, accuracy and the reliability of identification result are high.

Summary of the invention

The object of the invention is to, a kind of power network topology misidentification system and method thereof based on road-loop equation is provided, useIn the accurate identification that realizes power network topology mistake.

To achieve these goals, the present invention propose technical scheme be, a kind of power network topology mistake based on road-loop equationIdentification system, it is characterized in that described system comprise data acquisition module, branch current computing module, topology error identification module,Bad data recognition module and result output module;

Described data acquisition module, branch current computing module, topology error identification module, bad data recognition module and resultOutput module is linked in sequence;

Described topology error identification module is connected with branch current computing module respectively with bad data recognition module;

Described data acquisition module for collection network structural parameters, interconnection switch state, circuit-breaker status, branch road rated current,Node Injection Current, branch current measured value and node voltage, and the data of collection are sent to branch current computing module and open upFlutter misidentification module;

Described branch current computing module is described the grid topology data of topological structure of electric and asks for branch current and calculate for generatingValue, more described grid topology data and branch current calculated value are sent to topology error identification module;

Described topology error identification module is for identification power network topology mistake; In the time that mistake appears in power network topology, upgrade power network topologyData and interdependent node Injection Current, and the data after upgrading are sent to branch current computing module; When power network topology does not occurWhen mistake, the data of grid topology data, branch current calculated value and collection are sent to bad data recognition module;

Described bad data recognition module is for the bad data of identification node Injection Current or branch current measured value; Work as existenceWhen bad data, revise relevant bad data, and revised data are sent to branch current computing module; When not existing notWhen good data, grid topology data and branch current measured value are sent to result output module;

Result output module output grid topology data and branch current measured value.

A power network topology misidentification method based on road-loop equation, is characterized in that described method comprises:

Step 1: image data, comprise network architecture parameters, interconnection switch state, circuit-breaker status, branch road rated current,Node Injection Current, branch current measured value and node voltage;

Step 2: ask for branch current calculated value;

Step 3: identification power network topology mistake; When power network topology occurs when wrong, more new node Injection Current, path matrix andReturn-Zhi incidence matrix, then return to step 2; In the time there is not mistake in power network topology, execution step 4;

Step 4: identification bad data; In the time there is bad data, revise relevant bad data, then perform step 2; When notWhile there is bad data, grid topology data and branch current measured value are sent to result output module;

Step 5: output grid topology data and branch current measured value.

The present invention utilizes network topology constraint and Kirchhoff's law, the synchronous electric tolerance information providing by PMU, set up road-Loop equation, calculates branch current, in the situation that considering multiple Topology Error and bad data, according to calculated value and measured valueBetween difference topology information and branch current measuring value are carried out to verification, simulation result shows, this invention be not subject to Topology Error with notThe impact of good data double factor, accuracy and the reliability of identification result are high.

Brief description of the drawings

Fig. 1 is the power network topology misidentification system construction drawing based on road-loop equation;

Fig. 2 is IEEE9 node system road-loop signature;

Fig. 3 is IEEE3 machine 9 node system road-loop equation comparison of computational results tables;

Fig. 4 is the result of calculation table under branch road L1 disconnection;

Fig. 5 is result of calculation table after topology information correction;

Fig. 6 is system road-loop signature after L6 disconnects;

Fig. 7 is result of calculation table after L6 disconnects;

Fig. 8 is result of calculation table after the correction of L6 topology information;

Fig. 9 is result of calculation table after Node B 6 bad data corrections;

Figure 10 is road-loop signature after L6 is connected with B2;

Figure 11 is result of calculation table after L6 is connected with B2;

Figure 12 is result of calculation table in the equal closed situation of branch road;

Figure 13 is result of calculation table after L6 disconnects;

Figure 14 is IEEE39 node system road-loop signature;

Figure 15 is with nodeFor localized network road-loop signature of terminal;

Figure 16 is the network calculations result table of Figure 15;

Figure 17 is nodeInjection Current is not measured result of calculation table after data correction;

Figure 18 is nodeInjection Current is not measured result of calculation table after data correction;

Figure 19 is localized network road-loop signature in IEEE39 node system;

Figure 20 is the network calculations result table of Figure 19;

Figure 21 is that branch road 29 electric currents are not measured result of calculation table after data correction.

Detailed description of the invention

Below in conjunction with accompanying drawing, preferred embodiment is elaborated. Should be emphasized that, following explanation is only exemplary,Instead of in order to limit the scope of the invention and to apply.

Embodiment 1

Fig. 1 is the power network topology misidentification system construction drawing based on road-loop equation provided by the invention, as shown in Figure 1,Power network topology misidentification system based on road-loop equation comprises data acquisition module, branch current computing module, topology mistakeMistake recognition module, bad data recognition module and result output module. Wherein, data acquisition module, branch current computing module,Topology error identification module, bad data recognition module and result output module are linked in sequence, and topology error identification module andBad data recognition module is also connected with branch current computing module respectively.

Data acquisition module is for collection network structural parameters, interconnection switch state, circuit-breaker status, branch road rated current, jointPoint Injection Current, branch current measured value and node voltage, and the data of collection are sent to branch current computing module and topologyMisidentification module. Circuit-breaker status connects grid nodes branch road for determining is to disconnect or closure, and interconnection switch state is usedAny be connected with bar bus in electrical network in definite branch road.

Branch current computing module is described the grid topology data of topological structure of electric and asks for branch current calculated value for generating,And grid topology data and branch current calculated value are sent to topology error identification module. Branch current computing module is according to networkStructural parameters, interconnection switch state and circuit-breaker status generate the grid topology data of describing topological structure of electric, comprise road squareBattle array and return-Zhi incidence matrix. Branch current computing module is asked for according to path matrix, return-Zhi incidence matrix and node Injection CurrentBranch current calculated value.

Topology error identification module is for identification power network topology mistake. Power network topology mistake comprises that circuit-breaker status is for disconnection realityClosure, circuit-breaker status is the situations such as closed actual disconnection and double-bus misjudgment. Topology error identification module can rootAccording to imposing a condition, judge whether power network topology occurs mistake and power network topology type of error, and according to power network topology type of error,Upgrade grid topology data and interdependent node Injection Current. If mistake does not appear in power network topology, topology error identification module willThe data of grid topology data, branch current calculated value and collection are sent to bad data recognition module.

Bad data recognition module is for the bad data of identification node Injection Current or branch current measured value. If node noteEnter in electric current or branch current measured value and have bad data, revise the node Injection Current or the branch current that there are bad dataMeasured value, is sent to branch current computing module by revised data; In the time not there is not bad data, by grid topology dataBe sent to result output module with branch current measured value.

Result output module output grid topology data and branch current measured value.

Below, the general principle of the power network topology misidentification method based on road-loop equation provided by the invention is done in detailIllustrate, before this principle is described, first to the technical term that may use, comprise road, loop, fundamental circuit,Tree makes an explanation with chord.

Branch road refers to the circuit that connects two nodes in electrical network. In Fig. 2, branch road L5 is the circuit of connected node B8 and B9.

Loop refers to any closed path being made up of branch road. In Fig. 2, branch road L5, L7, L6, L4, L3 and L9 groupThe closed path becoming is exactly a loop.

Tree refers to the branch road of setting in electrical network, and in electrical network, tree refers to the connected graph that does not comprise loop but comprise all nodes in electrical network.

Chord is that the tree of removing in electrical network props up rear remaining branch road.

Fundamental circuit refers to the loop of only containing a chord.

Road refers to that the root to set in electrical network is starting point, flows to the set of fingers on the summit of tree through branch road. Road is directiveThe set of tree (tree that represents current direction props up) composition.

The general principle of the power network topology misidentification method based on road-loop equation is:

1. the function of data acquisition module.

The function of data acquisition module is to gather native system desired data, comprising: network architecture parameters, interconnection switch and breakerState, branch road rated current, node Injection Current, branch current measured value and node voltage.

2. the function of branch current computing module.

In electric power networks, road is that directive tree props up, and represents the flow direction of electric current. Road is taking the root of genealogical tree as starting point thus,Flow to the summit of tree through branch road. In path matrix T (l × n rank matrix, l is way, n is nodes), element definition is as follows:

Taking the electrical network shown in Fig. 2 as example, choose branch road L9 as chord, other branch road for tree, and with bus B1, B3,B6 is as the root of tree, and bus B2 is as the summit of tree. Road indicates with arrow. Can obtain path matrix suc as formula (2) institute by formula (1)Show, wherein, the part T corresponding with chord_LFor null matrix.

According to fundamental circuit each tree electric current and branch current direction, (L × l rank matrix, L is base to write back-Zhi of row incidence matrix BThis feeder number), regulation chord positive direction is loop positive direction, element b_liFor:

Can be obtained by formula (3), the return-Zhi incidence matrix B in Fig. 2 is:

B=[00-1-11-1101](4)

Branch current is made up of two parts: the one, and the contribution of node Injection Current to this branch road, the 2nd, loop current is in loopThe contribution on road. Known according to above-mentioned record, branch road comprises that tree props up and chord, and branch current measured value just comprises a tree electric current soMeasured value and chord current measurement value. If node Injection Current matrix isChord current measurement value matrix isBranch roadCurrent calculation value matrixCan be expressed as by road-loop equation:

${\stackrel{\·}{I}}_b^{\′}=T\×{\stackrel{\·}{I}}_N+B^T\×{\stackrel{\·}{I}}_L---\left(5\right)$

More for interstitial content, and the localized network of wiring complex large power grid, road-loop equation is still suitable for. Suppose nodeI is the starting point of road in localized network, and branch road k and branch road t are respectively taking node i as terminal with starting point. Can be obtained by formula (6), rightIn the starting point i of localized network road, i such as its Injection Current such as value node such as grade_Ni' equal the branch current i taking this node as terminal_lkWith this jointPoint impressed current i_NiWith, deduct branch road k loop currentResult. Thus, calculate successively localized network according to formula (6)The equivalent Injection Current of starting point, can form localized network with the Injection Current of other internal nodeSubstitution formula (5) can obtainBranch current in localized network

$i_{\mathrm{lt}}=T_t\×{\stackrel{\·}{I}}_N+B_t\×{\stackrel{\·}{I}}_L$

$=T_k\×{\stackrel{\·}{I}}_N+B_k\×{\stackrel{\·}{I}}_L+i_{\mathrm{Ni}}-B_k\×{\stackrel{\·}{I}}_L+B_t\×{\stackrel{\·}{I}}_L$

$=(i_{\mathrm{lk}}+i_{\mathrm{Ni}}-B_k\×{\stackrel{\·}{I}}_L)+B_t\×{\stackrel{\·}{I}}_L$

In formula (6), i_NiFor the Injection Current of node i, T_tThe t that represents path matrix T is capable, B_tAnd B_kRepresent respectivelyReturn-the t of Zhi incidence matrix B is capable and k is capable.

In solution procedure, source current and load current are considered as to node Injection Current; Meanwhile, take into account branch road admittance over the ground,And by equivalent π type branch road over the ground the equal reduction of admittance electric current be the Injection Current of branch road end bus. If the head end of branch road k and endEnd bus nodes is respectively j and i, admittance electric current over the groundWherein,Represent branch road kSusceptance,WithRepresent the magnitude of voltage of node j and i.

3. the function of topology error identification module.

First,, in the time judging that whether branch road is closed, mainly investigate branch current measured value | i_Lk|>ε₁Whether set up. The present inventionIn, ε₁For branch road rated current0.08 times,

In addition, in electrical network, node Injection Current sum should meet Kirchhoff's theorem,The present inventionIn, ε₂=k×n×0.2%×max{|i_Bi|. Wherein, k is the reliable system being determined by the allowable error of actual measurement deviceNumber (getting 1 in the present invention), n is summing junction number, 0.2% is the relative error of PMU measurement amount, max{|i_Bi| be summationThe maximum of node Injection Current absolute value.

Have again, determine and impose a condition: while there is not Topology Error and bad data, arbitrary branch current measured value and calculatingError between value | i_Lk-i_Lk′|<ε₃, wherein, ε₃Get 0.3% of maximum branch current measured value absolute value,ε₃=0.3%×|max{i_Lk}|。i_LkAnd i_LkRepresent respectively branch current measured value and the calculated value of branch road k.

Secondly, carry out Topology Error and bad data identification according to above-mentioned condition.

Electric power networks Topology Error, be generally divided into circuit breaker switch state closed and actually disconnect, circuit breaker switch state disconnect andActual closed and 3 kinds of situations of two female wiring misjudgments.

If node i is the endpoint node of Topology Error branch road k, i_ΔkFor this branch road admittance electric current over the ground. By node in T,InNode current and branch road according to the far and near degree sequence apart from road root. Be that node is according to suitable apart from the distance of road rootAfter order is arranged, then write each node corresponding current according to these order row, branch road is arranged according to the order of its corresponding start node.If after in road, node i comes m node, after the branch road k taking node i as start node comes m-1 bar branch road.

(1) the closed and actual situation disconnecting of circuit breaker switch state.

Circuit breaker switch state is embodied by branch switch state, when therefore when certain branch switch state is closed, reality disconnects, asksGet this branch road endpoint node Injection Current and will increase i_Δk, now road-loop equation is suc as formula (7).

From formula (7), branch switch state for closed reality be under disconnection, the branch current measured value of Topology Error is littleIn ε₁, and in road, the branch current after this branch road does not all meet and imposes a condition, and electric current difference and Topology Error branch road is rightGround admittance is current related.

${\stackrel{\&CenterDot;}{I}}_b^{\&prime;}=\left[\begin{array}{cc}{T}_{(m-1)\&times;m}& T_{m\&times;(n-m)}\\ T_{(l+1-m)\&times;m}& T_{(l+1-m)\&times;(n-m)}\end{array}\right]\&times;{\left[\begin{array}{ccc}{i}_{B1}...& i_{\mathrm{Bk}}+i_{\mathrm{\&Delta;k}}...& i_{\mathrm{Bn}}\end{array}\right]}^T+B^T\&times;{\stackrel{\&CenterDot;}{I}}_L$

(2) on off state disconnects and actual closed situation.

In the time that certain branch switch state for disconnection is actual is closure, this branch road endpoint node Injection Current will reduce i_Δk, by formula (8), topological branch road occur wrong after branch current all do not meet and impose a condition, and difference and Topology Error branch current and over the groundCurrent related.

${\stackrel{\&CenterDot;}{I}}_b^{\&prime;}=\left[\begin{array}{cc}{T}_{(m-1)\&times;m}& 0\\ 0& T_{(l+1-m)\&times;(n-m)}\end{array}\right]\&times;{\left[\begin{array}{ccc}{i}_{B1}...& i_{\mathrm{Bk}}-i_{\mathrm{\&Delta;k}}...& i_{\mathrm{Bn}}\end{array}\right]}^T+B^T\&times;{\stackrel{\&CenterDot;}{I}}_L$

If the topological state of closed chord is for disconnecting, chord endpoint node Injection Current will be affected, and cause branch road electricity in loopStream does not meet and imposes a condition, and this difference and chord are current related, and in road, is positioned at the less difference of branch current appearance behind loop,Still do not meet and impose a condition, electrical conduction current is relevant over the ground with chord for this difference.

(3) the wrongheaded situation of two female wiring.

For two female plant stand outlets that connect, to establish between node i and node u and can carry out grid switching operation, its outlet is k, and twoBetween bus, there is s bar branch road. On off state is that branch road k is connected with node u, and actual branch road k is connected with node i, according to formula (9)Known, between the branch current calculated value between two buses and measured value, all there is difference, and difference and branch road k admittance electric current over the groundAnd place loop current is relevant.

${\stackrel{\&CenterDot;}{I}}_b^{\&prime;}=\left[\begin{array}{cc}{T}_{m-\&times;m}& T_{m\&times;(n-m)}\\ T_{s\&times;m}^{\&prime;}& T_{s\&times;(n-m)}^{\&prime;}\\ T_{(l-s-m)\&times;m}& T_{(l-s-m)\&times;(n-m)}\end{array}\right]\&times;{\left[\begin{array}{cccc}{i}_{B1}...& i_{\mathrm{Bk}}-i_{\mathrm{\&Delta;k}}...& i_{\mathrm{Bu}}+i_{\mathrm{\&Delta;k}}...& i_{\mathrm{Bu}}\end{array}\right]}^T+{\left[\begin{array}{ccc}{B}_{L\&times;(m-1)}& B_{L\&times;s}^{\&prime;}& B_{L\&times;(l+1-s-m)}\end{array}\right]}^T\&times;{\stackrel{\&CenterDot;}{I}}_L$

According to above-mentioned analysis, the step of utilizing topology error identification module to carry out misidentification is:

Step a1: certain chord disconnects, but its current measurement value is greater than ε₁, and branch current in this loop do not meet and imposes a condition,This chord is actual is closed. Certain tree disconnects, but its Current calculation value is greater than ε₁, and on road, this tree props up after endpoint nodeAll branches electric current does not all meet and imposes a condition, this tree Zhi Shiwei closure.

Step a2: if branch road closure, but its calculated value is less than ε₁, and in system road, all branches electric current after this branch road is discontentedFoot imposes a condition, and this branch road is real in disconnecting.

Step a3: if branch road closure, its calculated value is less than ε₁, but after by its branch road, admittance electric current deducts over the ground, node current andIncrease, this branch road topology information is correct, branch road underloading.

Step a4: for the branch road that can carry out grid switching operation, its calculated value and measured value are greater than ε₁And closed, but between two busesBranch current measured value does not meet and imposes a condition, this branch road bus connection judgment mistake.

According to above-mentioned steps detection branch topology, if occur, Topology Error upgrades the node Injection Current matrix of chord endPath matrix T and return-Zhi incidence matrix B, return branch Current calculation module, recalculatesAnd judgement againWhether there is Topology Error. For circuit breaker switch state is closed, actual disconnection and circuit breaker switch state disconnect and realityClosed situation, more new node Injection Current matrixOnly need upgrade prop up/branch road endpoint node of wrongheaded chord/treeNode Injection Current measured value. For the wrongheaded situation of two female wiring, more new node Injection Current matrixRefer to moreNewly can carry out the node Injection Current of the connection bus of the branch road of grid switching operation.

For circuit breaker switch state is closed, actual disconnection and circuit breaker switch state disconnect and actual closed situation, willBreaker is revised as actual open/close state, then upgrades path matrix T and return-Zhi incidence matrix B. For twoThe wrongheaded situation of female wiring, according to interconnection switch virtual condition, upgrade path matrix T and return-Zhi incidence matrix BCan.

4. the function of bad data recognition module.

In order further to improve topology error identification ability, also need effectively to identify bad data, and it is revised. Due to roadIn road-loop equation, comprise chord electric current and node current, therefore need first to verify that whether node Injection Current is correct.

First, if bad data appears in node Injection Current, node Injection Current does not meet Kirchhoff's theorem, i.e. node noteEnter electric current sum and be greater than ε₂. According to formula (7), occur all existing between the branch current calculated value of bad data node and measured valueDifference, difference is bad data error and can be according to Kirchhoff's law correction node Injection Current just.

If there is bad data in chord current measurement value, can be obtained by formula (10), the branch current calculated value in loop and measured value itBetween all there is difference, difference is also that (wherein, Δ i represents the error of bad data, B to bad data error just_kFor the k of BRow).

${\stackrel{\&CenterDot;}{I}}_b^{\&prime;}=T\&times;{\stackrel{\&CenterDot;}{I}}_N+B^T\&times;{\left[\begin{array}{ccc}{i}_{L1}...& i_{\mathrm{Lk}}+\mathrm{\&Delta;i}...& i_{\mathrm{Lt}}\end{array}\right]}^T$

$=T\&times;{\stackrel{\&CenterDot;}{I}}_N+B^T\&times;{\stackrel{\&CenterDot;}{I}}_L+B_k^T\&times;\mathrm{\&Delta;i}---\left(10\right)$

$={\stackrel{\&CenterDot;}{I}}_b+B_k^T\&times;\mathrm{\&Delta;i}$

If there is bad data in a tree electric current, do not affect asking for of calculated value, can directly utilize calculated value to repair measured value valueChange.

According to above-mentioned analysis, the step of utilizing bad data recognition module to carry out bad data identification is:

Step b1: ask for system node Injection Current sum, if node Injection Current sum does not meet Kirchhoff's law,And the branch current in system road after a certain power supply or load bus does not all meet and imposes a condition, this nodeThere is bad data in Injection Current, revises according to Kirchhoff's theorem or according to difference.

Step b2: if the branch current measured value in a certain loop does not meet and imposes a condition, the chord electric current in this loop goes outExisting bad data, props up the difference of Current calculation value and measured value and revises according to the tree in loop, described chord place.

Step b3: a tree current measurement value does not meet and imposes a condition, and can prop up Current calculation value with the tree calculating measured value is enteredRow is revised.

After bad data correction, return branch Current calculation module, recalculatesUntil all branch current measured valuesMeet and impose a condition.

5. the function of result output module.

Output grid topology data and branch current measured value. Wherein, grid topology data comprises path matrix, returns-Zhi GuanlianMatrix, circuit-breaker status and interconnection switch state.

According to above-mentioned principle, the power network topology misidentification method based on road-loop equation provided by the invention comprises:

Step 1: image data, comprise network architecture parameters, interconnection switch state, circuit-breaker status, branch road rated current,Node Injection Current, branch current measured value and node voltage.

Step 2: ask for branch current calculated value.

Ask for branch current calculated value and adopt formula:Wherein,For branch current calculated value squareBattle array, T is the path matrix being formed by power network topology,For node Injection Current matrix, B is returned by the basic of power network topologyReturn-Zhi the incidence matrix of each tree electric current and branch current orientation determination in road,For the chord electricity being formed by the chord in branch roadFlow measurement value matrix.

Step 3: identification power network topology mistake, specifically comprises:

Sub-step A1: for the chord in off-state, if described chord current measurement value is greater than the first setting threshold ε₁，And in the residing loop of described chord, the branch current measured value of any branch road does not meet and imposes a condition, the actual place of described chordIn closure state, upgrade node Injection Current, path matrix and the return-Zhi incidence matrix of described chord end, return to step 2.

The node Injection Current that upgrades chord end adopts formula i_Bk′=i_Bk+i_Δk. Wherein, i_Bk' be the chord end after upgradingNode Injection Current, i_BkFor the node Injection Current of the chord end before upgrading, i_ΔkFor described chord over the ground admittance electric current andJ is imaginary unit,For the susceptance of described chord,WithBe respectively described chord two ends jointThe voltage of point. Due to the misjudgment of chord state, therefore revise chord state, and upgrade road according to amended chord stateMatrix and return-Zhi incidence matrix.

Sub-step A2: prop up for the tree in off-state, be greater than the first setting threshold ε if described tree props up Current calculation value₁，And the branch current measured value that on road, this tree props up all branches after endpoint node does not meet and imposes a condition, and described tree props up realityNode Injection Current, path matrix and the return-Zhi incidence matrix of a tree end, in closure state, upgraded in border, returns to step 2.

The node Injection Current that upgrades a tree end adopts formula i_Bk′=i_Bk+i_Δk. Wherein, i_Bk' prop up end for the tree after upgradingNode Injection Current, i_BkFor the tree before upgrading props up the node Injection Current of end, i_ΔkFor described tree prop up over the ground admittance electric current andJ is imaginary unit,The susceptance propping up for described tree,WithBe respectively tree two end nodesVoltage. Due to a tree state misjudgment, a therefore amendment tree state, and prop up state according to amended tree and upgrade path matrixWith return-Zhi incidence matrix.

Sub-step A3: for the branch road in closure state, if described branch current calculated value is less than the first setting threshold ε₁，And the branch current of all branch roads after the above branch road of road does not meet and imposes a condition, described branch road reality is in disconnectingState, node Injection Current, path matrix and the return-Zhi incidence matrix of renewal branch road end, return to step 2.

The node Injection Current that upgrades branch road end adopts formula i_Bk′=i_Bk-i_Δk. Wherein, i_Bk' be the branch road end after upgradingNode Injection Current, i_BkFor the node Injection Current of the branch road end before upgrading, i_ΔkFor described branch road over the ground admittance electric current andJ is imaginary unit,For the susceptance of described branch road,WithBe respectively branch road two end nodesVoltage. Due to a line state misjudgment, a therefore amendment line state, and upgrade path matrix according to amended line stateWith return-Zhi incidence matrix.

Sub-step A4: for the branch road in closure state, if described branch current calculated value is less than the first setting threshold ε₁，And after the electric current of admittance over the ground of described branch road is deducted, all node Injection Current sums increase, and branch road topology information is correct,Branch road underloading, skips to step 4.

Because admittance electric current is over the ground a part for node Injection Current, according to Kirchhoff's theorem, admittance current value impact over the groundThe result of calculation of node Injection Current sum. If this branch road is closed, when computing node Injection Current sum, right by this branch roadGround admittance electric current (negative value) counts, and causes all node Injection Current sums to increase.

Sub-step A5: for the branch road that can carry out grid switching operation, if the branch current calculated value of described branch road and branch current are surveyedValue is all greater than the first setting threshold ε₁And described branch road is in closure state, but connect the branch road electricity between two buses of described branch roadFlow measurement value does not meet and imposes a condition, described branch road bus connection judgment mistake, and renewal can be carried out the branch road of grid switching operation with femaleNode Injection Current, path matrix and return-Zhi incidence matrix that line connects, return to step 2.

Wherein, renewal can be carried out the node Injection Current that the branch road of grid switching operation is connected with bus and adopts formula $\left\{\begin{array}{c}{i}_{\mathrm{Bu}}^{\&prime;}=i_{\mathrm{Bu}}-i_{\mathrm{\&Delta;k}}\\ i_{\mathrm{Bv}}^{\&prime;}=i_{\mathrm{Bv}}+i_{\mathrm{\&Delta;k}}\end{array}\right..$ Wherein, i_BuNode Injection Current after the ' node updates that is connected with bus for the branch road reality that can carry out grid switching operation, i_BuFor canCarry out the node Injection Current before node updates that the branch road reality of grid switching operation is connected with bus, i_Bv' be to carry out grid switching operationNode Injection Current in branch road after the actual node updates not being connected with bus, i_BvActual for carrying out in the branch road of grid switching operationNode Injection Current before the node updates not being connected with bus, i_ΔkFor can carry out grid switching operation branch road the electric current of admittance over the ground andJ is imaginary unit,For carrying out the susceptance of the branch road of grid switching operation,WithBeing respectively canCarry out the voltage of branch road two end nodes of grid switching operation. Owing to can carrying out the branch road of grid switching operation and the connection status of bus has occurredChange, therefore can carry out the branch road of grid switching operation and the connection status of bus renewal path matrix and return-Zhi Guanlian according to realityMatrix.

Step 4: identification bad data, specifically comprises:

Sub-step B1: calculate node Injection Current sum in electrical network, if if all node Injection Current sums in electrical networkAnd in road, there is power supply node or load bus, the branch road after described power supply node or load busCurrent measurement value does not meet and imposes a condition, and bad data appears in the node Injection Current of this power supply node or load bus,The node Injection Current of revising this power supply node or load bus, then returns to step 2. Wherein, i_BiFor node i in electrical networkInjection Current, n is node number in electrical network, ε₂It is the second setting threshold. Revise the node note of power supply node or load busEnter electric current and adopt one of following two kinds of modes:

(1) the node Injection Current of correction power supply node or load bus, meets all node Injection Current sums $\left|\underset{i=1}{\overset{n}{\mathrm{\&Sigma;}}}{i}_{\mathrm{Bi}}\right|<{\mathrm{\&epsiv;}}_2.$

(2) select in the branch road after described power supply node or load bus, the measured value of branch current and the difference of calculated value are exhaustedTo being worth maximum setting bar branch road, by the measured value of branch current of setting bar branch road and the average of the difference of calculated value selected,Inject electricity with the node Injection Current sum of power supply node or load bus as the node of described this power supply node or load busStream.

Sub-step B2: if there is a loop, the branch current measured value in this loop does not meet and imposes a condition, this loopIn chord current measurement value there is bad data, prop up the poor of Current calculation value and measured value with the tree in loop, described chord placeBe worth and this chord current measurement value sum, replace the chord current measurement value of this chord, then return to step 2.

Sub-step B3: if tree props up electric current and do not meet and impose a condition, replaces a tree current measurement value by a tree Current calculation value,Then return to step 2.

Step 5: output grid topology data and branch current measured value.

Below in conjunction with two embodiment more specifically, correctness of the present invention and validity are verified.

Embodiment 2

Based on PSCAD simulation software, build the IEEE3 machine 9 node system models shown in Fig. 2. Suppose bus B2 and B7Can grid switching operation. Wherein, system power supply S_N=100MVA，U_N=220KV, ${\stackrel{\&CenterDot;}{I}}_{\mathrm{LN}}=(0.223+j0.138)\mathrm{kA},$ ε₁=(0.01785+j0.0111)kA。

Formula (5) is verified, its branch road over the ground admittance is B/2=1.623 × 10^-4S, after arranging according to mentioned above principleNode Injection Current is suc as formula shown in (11), and loop current is i_L9=(0.43628-j0.216385) kA, result of calculation asShown in Fig. 3.

Impose a condition because the each branch current of system meets, do not have topology information mistake and bad data.

${\stackrel{\&CenterDot;}{I}}_N=\left[\begin{array}{c}0.79557\\ 0.8265\\ 0.79387\\ 0.05474\\ -0.84991\\ -0.87182\\ 0.04408\\ -0.84595\\ 0.05471\end{array}\right]+j\left[\begin{array}{c}0.45563\\ 0.45128\\ 0.45778\\ -0.013094\\ -0.44277\\ -0.43429\\ -0.01793\\ -0.44316\\ -0.013036\end{array}\right]\mathrm{kA}---\left(11\right)$

(1) switch disconnects and actual closed with bad data and deposit.

In Fig. 2, if except branch road L1 disconnects, all the other are all closed, and the T of system, B matrix are formula (12), and node injectsElectric current is formula (13), and chord electric current is i_L9=(0.43628-j0.216385) kA, result of calculation as shown in Figure 4.

Analysis mode (13) and Fig. 4, ε₂=(1.255+j0.659))×10^-2kA，ε₃=(2.478+j1.733)×10^-3kA，L1Branch road afterwards does not all meet and imposes a condition, and L1 Current calculation value is greater than ε₁, therefore judge that branch road L1 is actual in closed. RepairChange its topology information, T, B matrix and the node Injection Current after renewal be suc as formula shown in (2), (4), (11), result of calculationAs shown in Figure 5.

As can be seen from Figure 5, branch road L4 does not still meet and imposes a condition, and its branch road two ends bus can not carry out grid switching operation,Judge branch road L4 metric data mistake, directly utilize calculated value correction.

${\stackrel{\&CenterDot;}{I}}_N=\left[\begin{array}{c}0.79557\\ 0.8265\\ 0.79387\\ 0.02205\\ -0.84991\\ -0.87182\\ 0.04408\\ -0.84595\\ 0.05471\end{array}\right]+j\left[\begin{array}{c}0.45563\\ 0.45128\\ 0.45778\\ -0.00898\\ -0.44277\\ -0.43429\\ -0.01793\\ -0.44316\\ -0.013036\end{array}\right]\mathrm{kA}---\left(13\right)$

(2) switch disconnects and actual closed with bad data and deposit.

Disconnect if system topological information is branch road L6, the branch road that loop is broken is designated as chord, and its road direction is as Fig. 6Shown in. This sytem matrix T, B are formula (14), and node Injection Current is suc as formula shown in (15), and result of calculation as shown in Figure 7.

Analysis mode (15) and Fig. 7, ε₂=(1.2554+j0.6592)×10^-2kA，ε₃=(2.478+j1.733))×10^-3kA，Disconnected branches L6 calculates electric current and is greater than ε₁, and in road, the branch current behind its loop, place and loop does not all meet and imposes a condition,Determine that branch road L6 is actual in closed. After amendment topology information, T, B are suc as formula shown in (2), (4), and node Injection Current is formula(16), result of calculation as shown in Figure 8.

${\stackrel{\&CenterDot;}{I}}_N=\left[\begin{array}{c}0.79557\\ 0.8265\\ 0.79387\\ 0.05473\\ -0.87196\\ -0.02205\\ 0.02204\\ -0.84595\\ 0.05471\end{array}\right]+j\left[\begin{array}{c}0.45563\\ 0.45128\\ 0.45778\\ -0.0131\\ -0.43379\\ -0.00898\\ -0.00896\\ -0.44316\\ -0.013036\end{array}\right]\mathrm{kA}---\left(15\right)$

${\stackrel{\&CenterDot;}{I}}_N=\left[\begin{array}{c}0.79557\\ 0.8265\\ 0.79387\\ 0.05474\\ -0.84991\\ -0.02205\\ 0.04408\\ -0.84595\\ 0.05471\end{array}\right]+j\left[\begin{array}{c}0.45563\\ 0.45128\\ 0.45778\\ -0.013094\\ -0.44277\\ -0.008975\\ -0.01793\\ -0.44316\\ -0.013036\end{array}\right]\mathrm{kA}---\left(16\right)$

Analysis mode (16) and Fig. 8, branch current is all greater than ε₁, but node Injection Current sum does not meet Kirchhoff's theorem, andAfter load bus B6, branch current does not all meet and imposes a condition, and judges that bad data appears in B6 Injection Current. According to jointPut Injection Current and revise, result, suc as formula (17), is calculated rear result as shown in Figure 9 by road-loop equation, itsRoad electric current all meets and imposes a condition, and now, system topological information and measuring value are correct.

${\stackrel{\&CenterDot;}{I}}_N=\left[\begin{array}{c}0.79557\\ 0.8265\\ 0.79387\\ 0.05474\\ -0.84991\\ -0.85155\\ 0.04408\\ -0.84595\\ 0.05471\end{array}\right]+j\left[\begin{array}{c}0.45563\\ 0.45128\\ 0.45778\\ -0.013094\\ -0.44277\\ -0.44368\\ -0.01793\\ -0.44316\\ -0.013036\end{array}\right]\mathrm{kA}---\left(17\right)$

(3) double bus scheme misjudgment and bad data deposit.

If system topological information is as Figure 10, its T, B matrix are suc as formula (18), and node Injection Current is formula (19), result of calculationAs Figure 11.

Analysis Figure 11 is known, and branch road L6 is greater than setting threshold ε₁, but carry out between two bus B2, the B7 of grid switching operation after L6Branch current do not meet and impose a condition, its difference and loop, branch road L6 place and this line-to-ground admittance difference between current approach, and sentenceDisconnected L6 bus connects topology information mistake. Amendment topology information, T, B matrix and the node Injection Current after renewal suc as formula(2), shown in (4), (11), as shown in Figure 3, topology information and measuring value are all correct for result of calculation.

${\stackrel{\&CenterDot;}{I}}_N=\left[\begin{array}{c}0.79557\\ 0.84854\\ 0.79387\\ 0.05474\\ -0.84991\\ -0.87182\\ 0.02204\\ -0.84595\\ 0.05471\end{array}\right]+j\left[\begin{array}{c}0.45563\\ 0.44232\\ 0.45778\\ -0.013094\\ -0.44277\\ -0.43429\\ -0.008962\\ -0.44316\\ -0.013036\end{array}\right]\mathrm{kA}---\left(19\right)$

(4) closed and actual disconnection and bad data of switch depositing.

If branch road is all closed in system shown in Figure 4, its T, B matrix be suc as formula (2), (4), and node Injection Current is suc as formula (20),Be ε according to data threshold value value₂=(1.676+j0.9734)×10^-2kA，ε₃=(2.793+j1.324)×10^-3kA，Result of calculation as shown in figure 12. The measured value of branch road L6 and calculated value are all less than ε₁, and after its endpoint node, branch current is notMeet and impose a condition, therefore judge that branch road L6 is real in disconnecting.

${\stackrel{\&CenterDot;}{I}}_N=\left[\begin{array}{c}0.93109\\ 0.56411\\ 0.76264\\ 0.05181\\ -0.65728\\ -0.83773\\ 0.04707\\ -0.8970\\ 0.05501\end{array}\right]+j\left[\begin{array}{c}0.43963\\ 0.33174\\ 0.44141\\ -0.01239\\ -0.2180\\ -0.42081\\ -0.01549\\ -0.54075\\ -0.01254\end{array}\right]\mathrm{kA}---\left(20\right)$

After the topology information of amendment branch road L6, as shown in Figure 6, T, B matrix are suc as formula shown in (14) for system road, and node injectsElectric current is formula (21), and as shown in figure 13, topology information and measurement amount are all correct for result of calculation.

${\stackrel{\&CenterDot;}{I}}_N=\left[\begin{array}{c}0.93109\\ 0.56411\\ 0.76264\\ 0.04891\\ -0.67487\\ -0.81724\\ 0.02574\\ -0.8970\\ 0.05501\end{array}\right]+j\left[\begin{array}{c}0.43963\\ 0.33174\\ 0.44141\\ -0.01219\\ -0.20969\\ -0.42933\\ -0.0007883\\ -0.54075\\ -0.01254\end{array}\right]\mathrm{kA}---\left(21\right)$

Embodiment 3

It is example that the present embodiment utilizes 10 machine 39 node systems, system architecture and pavement marker as shown in figure 14, wherein solid threeAngle arrow mark must be chord, and all the other branch roads are tree. The jot definite value of branch road isTherefore ε₁=(0.021544+j0.012933) kA. More for interstitial content, the network of wiring complexity, can carry out partTopology error identification, herein only taking two localized networks of Figure 14 institute mark as example.

(1) situation that many places bad data exists.

With nodeFor the localized network of terminal as shown in figure 15. Its T, B matrix be suc as formula shown in (22), and according to formula (6) pointAnalyse all the other branch currents of node Injection Current enabled node and (as in loop, remove its place with this node Injection Current equivalenceLoop current impact), the value node Injection Current such as this localized network, shown in (23), and chord electric currenti₂₆=(0.6675+j0.9609)kA，i₂₇=(0.2943-j0.2441) kA, its result of calculation as shown in figure 16.

According to formula (23) and Figure 16, threshold value value is ε₂=(4.3+j6.4)×10^-2kA，ε₃=(6.452+j9.652)×10^-3KA, nodeTotal output currentAll branches electric current is all greater than ε₁, without Topology Error. According to localized network Kirchhoff's theorem,With jointPoint Injection Current and absolute difference be greater than ε₂, branch road 19,20,25 electric currents all do not meet and impose a condition, wherein, and nodeNeither load bus, neither power supply node, decision nodeThere is difference in Injection Current. Consider chord electric current alsoMay be wrong, can not be directly with Kirchhoff's theorem correction node Injection Current. Relatively cause each line current difference because ofElement, can obtain branch road 19 differences and deduct branch road 25 differences, is nodeThe error amount of Injection Current, uses this difference pairInjection Current is revised to obtain i₁₂=(0.6614-j0.5166) kA, result of calculation as shown in figure 17.

Analyze Figure 17 data and find, the tree relevant to chord 26 props up electric current and all do not meet and impose a condition, and localized network node noteEnter electric current and still do not meet Kirchhoff's theorem, but both differences equate. Tentatively judge branch road 26 current error, use branch road 19Electric current difference it is revised to obtain to i₂₆=1.33495+j1.92183KA, then, uses revised measuring value to calculate,As shown in figure 18, electric parameters all meets Kirchhoff's theorem and imposes a condition result, without Topology Error and bad data.

For doubtful bad data, can pass through enlarged area scope, add the branch road that affected by bad data, further improveThe accuracy of topology error identification and bad data correction.

(2) on off state disconnects and actual closed situation.

Figure 19 is IEEE39 node zone line, and branch road 29 disconnects. Its T, B matrix are formula (24). Obtain according to formula (6)This localized network node Injection Current is suc as formula shown in (25), and result of calculation is as Figure 20.

According to the known node of Figure 19For road starting point, irrelevant with other node of one's respective area, need carry out separately Kirchhoff's theoremVerification. This region ε₃=(7.988+j6.904)×10^-3KA; For nodeε₂=(4.01+j3.45)×10^-3kA，All the other node summation threshold values are ε₂=(0.64+j1.59)×10^-2KA. Analyze Figure 20, the measured value of known chord 29 is greater than ε₁，Be not inconsistent with topology information, and branch current in this loop all do not meet and impose a condition, therefore, judge branch road 29 Topology Errors.Change B matrix the first row in formula (24) into [1110]. Amendment topology after, result of calculation as shown in figure 21, from figureData can find out, its branch current meets and is greater than ε₁And meet and impose a condition, and this localized network node Injection Current meets base, now, there is not Topology Error and bad data in that Hough theorem.

The above, be only preferably detailed description of the invention of the present invention, but protection scope of the present invention is not limited to this, appointsWhat is familiar with those skilled in the art in the technical scope of the present invention's exposure, the variation that can expect easily or replacement, allWithin should being encompassed in protection scope of the present invention. Therefore, protection scope of the present invention should taking the protection domain of claim asAccurate.

Claims (5)

1. the power network topology misidentification system based on road-loop equation, is characterized in that described system comprises data acquisition modulePiece, branch current computing module, topology error identification module, bad data recognition module and result output module;

Described data acquisition module, branch current computing module, topology error identification module, bad data recognition module and resultOutput module is linked in sequence;

The output of the output of described topology error identification module and bad data recognition module respectively with branch current computing moduleInput connect;

The output of described data acquisition module is connected with the input of topology error identification module;

Described data acquisition module for collection network structural parameters, interconnection switch state, circuit-breaker status, branch road rated current,Node Injection Current, branch current measured value and node voltage, and the data of collection are sent to branch current computing module and open upFlutter misidentification module;

Described branch current computing module is described the grid topology data of topological structure of electric and asks for branch current and calculate for generatingValue, more described grid topology data and branch current calculated value are sent to topology error identification module;

Described topology error identification module is for identification power network topology mistake; In the time that mistake appears in power network topology, upgrade power network topologyData and interdependent node Injection Current, and the data after upgrading are sent to branch current computing module; When power network topology does not occurWhen mistake, the data of grid topology data, branch current calculated value and collection are sent to bad data recognition module;

Described bad data recognition module is for the bad data of identification node Injection Current or branch current measured value; Work as existenceWhen bad data, revise relevant bad data, and revised data are sent to branch current computing module; When not existing notWhen good data, grid topology data and branch current measured value are sent to result output module;

Result output module output grid topology data and branch current measured value.

2. the power network topology misidentification method based on road-loop equation, is characterized in that described method comprises:

Step 1: image data, comprise network architecture parameters, interconnection switch state, circuit-breaker status, branch road rated current,Node Injection Current, branch current measured value and node voltage;

Step 2: ask for branch current calculated value;

Step 3: identification power network topology mistake;

Step 4: identification bad data;

Step 5: output grid topology data and branch current measured value;

In described step 2, ask for branch current calculated value and adopt formula:

Wherein,For branch current calculated value matrix;

T is path matrix;

For node Injection Current matrix;

Be back-Zhi of B incidence matrix;

For the chord current measurement value matrix being formed by the chord in branch road;

In described step 3, identification power network topology mistake comprises:

Sub-step A1: for the chord in off-state, if described chord current measurement value is greater than the first setting threshold ε₁，And in the residing loop of described chord, the branch current measured value of any branch road does not meet and imposes a condition, the actual place of described chordIn closure state, upgrade node Injection Current, path matrix and the return-Zhi incidence matrix of described chord end, return to step 2;

Sub-step A2: prop up for the tree in off-state, if tree props up Current calculation value and is greater than the first setting threshold ε₁, and roadThe branch current measured value that on road, this tree props up all branches after endpoint node does not meet and imposes a condition, described tree Zhi Shiji placeIn closure state, upgrade node Injection Current, path matrix and the return-Zhi incidence matrix of a tree end, return to step 2;

Sub-step A3: for the branch road in closure state, if described branch current calculated value is less than the first setting threshold ε₁，And the branch current measured value of all branch roads after the above branch road in closure state of road does not meet and imposes a condition,The described branch road reality in closure state is in off-state, upgrade node Injection Current, the path matrix of branch road end and return-Prop up incidence matrix, return to step 2;

Sub-step A4: for the branch road in closure state, if branch current calculated value is less than the first setting threshold ε₁, and willAfter the electric current of admittance over the ground of the described branch road in closure state deducts, node Injection Current sum increases, branch road topology informationCorrectly, branch road underloading, skips to step 4;

Sub-step A5: for the branch road that can carry out grid switching operation, if the branch current meter of the described branch road that carries out grid switching operationCalculation value and branch current measured value are all greater than the first setting threshold ε₁And the described branch road that carries out grid switching operation is in closure state,But the branch current measured value connecting between two buses of the described branch road that can carry out grid switching operation does not meet and imposes a condition, can described inCarry out the branch road bus connection judgment mistake of grid switching operation, renewal can be carried out the node that the branch road of grid switching operation is connected with bus and injectElectric current, path matrix and return-Zhi incidence matrix, return to step 2;

The node Injection Current of described renewal chord/tree end adopts formula i '_Bk＝i_Bk+i_Δk；

The node Injection Current of described renewal branch road end adopts formula i '_Bk＝i_Bk-i_Δk；

Wherein, i '_BkFor the node Injection Current of the prop up/branch road end of chord/tree after upgrading;

i_BkFor the node Injection Current of the prop up/branch road end of chord/tree before upgrading;

Described renewal can be carried out the node Injection Current that the branch road of grid switching operation is connected with bus and adopt formula $\left\{\begin{array}{c}{i}_{Bu}^{\&prime;}=i_{Bu}-i_{\mathrm{\&Delta;}k}\\ i_{Bv}^{\&prime;}=i_{Bv}+i_{\mathrm{\&Delta;}k}\end{array}\right.;$

Wherein, i '_BuFor carrying out the node Injection Current after node updates that the branch road reality of grid switching operation is connected with bus;

i_BuFor carrying out the node Injection Current before node updates that the branch road reality of grid switching operation is connected with bus;

i′_BvFor carrying out the node Injection Current after the actual node updates not being connected with bus in the branch road of grid switching operation;

i_BvFor carrying out the node Injection Current before the actual node updates not being connected with bus in the branch road of grid switching operation;

i_ΔkFor the electric current of admittance over the ground of the branch road of chord/tree/branch road/can carry out grid switching operation and

J is imaginary unit;

For chord/tree/branch road/can carry out the susceptance of the branch road of grid switching operation;

WithBe respectively chord/tree/branch road/can carry out the voltage of branch road two end nodes of grid switching operation;

In described step 4, identification bad data comprises:

Sub-step B1: calculate all node Injection Current sums in electrical network, if the absolute value of all node Injection Current sumsAnd in road, have power supply node/load bus, the branch current after described power supply node/load bus is surveyedValue does not meet and imposes a condition, and bad data appears in the node Injection Current of described power supply node/load bus, revises power supplyThe node Injection Current of node/load bus, then returns to step 2;

Wherein, the node Injection Current of described correction power supply node/load bus is to revise the node of power supply node/load busInjection Current, meets the absolute value of all node Injection Current sums

Or the node Injection Current of described correction power supply node/load bus is to select after described power supply node/load busBranch road in, select the conduct of the measured value of branch current and the absolute difference maximum of calculated value to set bar branch road, with what selectSet the average of the branch current measured value of bar branch road and the difference of calculated value, with the node Injection Current of power supply node/load busSum is as the node Injection Current of described power supply node/load bus;

Wherein, i_BiFor the Injection Current of node i in electrical network;

N is node number in electrical network;

ε₂It is the second setting threshold;

Sub-step B2: if exist a loop, the branch current measured value in described loop not meet impose a condition, described inThere is bad data in the chord current measurement value in loop, props up Current calculation value and measured value with the tree in loop, described chord placeDifference and described chord current measurement value sum, replace the chord current measurement value of described chord, then return to step 2;

Sub-step B3: if tree props up electric current and do not meet and impose a condition, replaces a tree current measurement value by a tree Current calculation value,Then return to step 2;

Described imposing a condition as the error of calculation of branch current measured value and branch current calculated value | i_Lk-i'_Lk|<ε₃；

Wherein i_LkFor branch current measured value;

i′_LkFor branch current calculated value;

ε₃It is the 3rd setting threshold.

3. discrimination method according to claim 2, is characterized in that described the first setting threshold ε₁For branch road rated current's0.08 times, ${\mathrm{\&epsiv;}}_1=0.08{\stackrel{\&CenterDot;}{I}}_{LN}.$

4. discrimination method according to claim 2, is characterized in that described the second setting thresholdε₂＝k×n×0.2％×max{|i_Bi|}；

Wherein, k is safety factor;

N is summing junction number;

max{|i_Bi| be the Injection Current absolute value maximum of node i in electrical network.

5. discrimination method according to claim 2, is characterized in that described the 3rd setting threshold ε₃Value is maximum branch current0.3% of absolute value, i.e. ε₃＝0.3％×|max{i_Lk|; Wherein, max{i_LkIt is maximum branch current measured value.