CN103823140A - Power grid topology error identification system and method based on road-loop equation - Google Patents

Abstract

The invention belongs to the technical field of topology analysis in an electric system and discloses a power grid topology error identification system and method based on a road-loop equation. The system comprises a data acquisition module, a branch current calculating module, a topology error identification module, a bad data identification module and a result outputting module, wherein the data acquisition module, the branch current calculating module, the topology error identification module, the bad data identification module and the result outputting module are sequentially connected, and the topology error identification module and the bad data identification module are both connected with the branch current calculating module. The method comprises the steps of acquiring data, solving the branch current calculation value, identifying power grid topology errors and updating data when power grid topology errors exist, identifying bad data and correcting relevant bad data when bad data exist, and outputting power grid topology data and the branch current measurement value at last. The power grid topology error identification system and method based on the road-loop equation are not affected by the two factors of topology errors and bad data and are high in identification accuracy and reliability.

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 misidentification system and method thereof based on road-loop equation.

Background technology

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

At present, Chinese scholars has proposed all multi-methods for electric system topology error identification, as: residual error method, regular method, minimum information loss method, hum pattern method, transfer trend method etc.But, classic method Data Source is comparatively single, the overwhelming majority is only by supervisory control and data acquisition system (supervisory control and data acquisition, SCADA), switching information is carried out to misidentification, such data collection cycle is long and asynchronous, needs front and back double sampling value toward contact, greatly reduces accuracy and the rapidity of topology error identification.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 Measurement System, WAMS) thereof provide new technological means for Power System Topology Analysis.For this reason, the synchronous electric tolerance information that this patent provides by phasor measurement unit (Phasor Measurement Unit, PMU), has proposed a kind of topology error identification system and method thereof based on road-loop equation.First this invention utilizes topological constraints and the Kirchhoff's law of network, road-loop equation of setting up, calculate branch current, on this basis, consider various Topology Errors and bad data the situation of depositing, according to the difference between calculated value and measuring value, topology information and branch current measuring value are carried out to verification.Show based on IEEE3 machine 9 node systems and IEEE10 machine 39 node system simulation results, this invention is not subject to the impact of Topology Error and bad data double factor, and 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, for realizing the accurate identification of power network topology mistake.

To achieve these goals, the technical scheme that the present invention proposes is, a power network topology misidentification system based on road-loop equation, is characterized in that described system comprises 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 result output module are 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 is used 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 topology error identification module;

Described branch current computing module is described the grid topology data of topological structure of electric and asks for branch current calculated value for generating, 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 grid topology data and interdependent node Injection Current, and the data after upgrading are sent to branch current computing module; In the time that mistake does not appear in power network topology, 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; In the time there is bad data, revise relevant bad data, and revised data are sent to branch current computing module; In the time not there is not bad 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, comprises 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; In the time that mistake appears in power network topology, more new node Injection Current, path matrix and return-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; In the time not there is not 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, calculate branch current, in the situation that considering multiple Topology Error and bad data, according to the difference between calculated value and measured value, topology information and branch current measuring value are carried out to verification, simulation result shows, this invention is not subject to the impact of Topology Error and bad data double factor, and accuracy and the reliability of identification result are high.

Accompanying drawing explanation

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 node

for localized network road-loop signature of terminal;

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

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

Figure 18 is node

injection 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.

Embodiment

Below in conjunction with accompanying drawing, preferred embodiment is elaborated.Should be emphasized that, following explanation is only exemplary, rather than 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, the power network topology misidentification system based on road-loop equation comprises data acquisition module, branch current computing module, topology error identification 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 is also connected with branch current computing module respectively with bad data recognition module.

Data acquisition module is used 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 topology error identification module.Circuit-breaker status connects grid nodes branch road for determining is to disconnect or closure, and interconnection switch state is for determining branch road with which bar bus of electrical network is connected.

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 generates the grid topology data of describing topological structure of electric according to network architecture parameters, interconnection switch state and circuit-breaker status, comprise path matrix and return-Zhi incidence matrix.Branch current computing module is asked for branch current calculated value according to path matrix, return-Zhi incidence matrix and node Injection Current.

Topology error identification module is for identification power network topology mistake.Power network topology mistake comprises that circuit-breaker status is actual closed for disconnection, and circuit-breaker status is the situations such as closed actual disconnection and double-bus misjudgment.Topology error identification module can be according to imposing a condition, and judges 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, the data of grid topology data, branch current calculated value and collection are sent to bad data recognition module by topology error identification module.

Bad data recognition module is for the bad data of identification node Injection Current or branch current measured value.If there is bad data in node Injection Current or branch current measured value, revise the node Injection Current or the branch current measured value that there are bad data, revised data are sent to branch current computing module; In the time not there is not bad 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.

Below, ultimate principle to the power network topology misidentification method based on road-loop equation provided by the invention elaborates, before this principle is described, first to the technical term that may use, comprise that road, loop, fundamental circuit, tree prop up and chord makes an explanation.

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, the closed path of branch road L5, L7, L6, L4, L3 and L9 composition 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 the set that directive tree props up (tree that represents current direction props up) composition.

The ultimate 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 circuit-breaker status, 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, take the root of genealogical tree as starting point, flows to the summit of tree through branch road thus.In path matrix T (l × n rank matrix, l is way, n is nodes), element definition is as follows:

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

According to fundamental circuit each tree electric current and branch current direction, row write back-Zhi incidence matrix B (L × l rank matrix, L is fundamental circuit number), regulation chord positive dirction is loop positive dirction, element b _lifor:

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

B=[0 0 -1 -1 1 -1 1 0 1] (4)

Branch current is made up of two parts: the one, and the contribution of node Injection Current to this branch road, the 2nd, the contribution of loop current to branch road in loop.Known according to above-mentioned record, branch road comprises that tree props up and chord, and branch current measured value just comprises tree current measurement value and a chord current measurement value so.If node Injection Current matrix is

chord current measurement value matrix is

branch current calculated value matrix can 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 that node i is the starting point of road in localized network, and branch road k and branch road t are respectively take node i as terminal with starting point.Can be obtained by formula (6), for 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 take this node as terminal _lkwith this node impressed current i _niwith, deduct branch road k loop current

result.Thus, calculate successively the equivalent Injection Current of localized network starting point according to formula (6), can form localized network with the Injection Current of other internal node

substitution formula (5) can obtain branch 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 _kthe t of represent back respectively-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 end bus nodes are respectively j and i, admittance electric current over the ground wherein, represent the susceptance of branch road k,

with

represent 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| > ε ₁whether set up.In the present invention, ε ₁for branch road rated current

0.08 times,

In addition, in electrical network, node Injection Current sum should meet Kirchhoff's theorem,

in the present invention, ε ₂=k × n × 0.2% × max{|i _bi|.Wherein, k is the safety factor (in the present invention get 1) definite by the permissible error of actual measurement device, and n is summing junction number, and 0.2% is the relative error of PMU measurement amount, max{|i _bi| be the maximal value of summing junction Injection Current absolute value.

Have again, determine and impose a condition: while there is not Topology Error and bad data, the error between arbitrary branch current measured value and calculated value | i _lk-i _lk' | < ε ₃, wherein, ε ₃get 0.3% of maximum branch current measured value absolute value, i.e. ε ₃=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 disconnects and actual 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 _{Δ k}for this branch road admittance electric current over the ground.By node in T,

in node current and branch road according to the far and near degree sequence apart from road root.Be after node is arranged according to the distance order apart from road root, 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 take 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 reality disconnects when certain branch switch state is closed, asks for this branch road endpoint node Injection Current and will increase i _{Δ k}, 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 less than ε ₁, and in road, the branch current after this branch road does not all meet and imposes a condition, and the admittance over the ground of electric current difference and Topology Error branch road is current related.

${\stackrel{\&CenterDot;}{I}}_b^{\&prime;}=\left[\begin{array}{cc}{T}_{(m-1)\&times;m}& T_{m\&times;(n-m)}\\ T_{(l+1-m)\&times;m}& T_{(l+1-m)\&times;(n-m)}\end{array}\right]\&times;{\left[\begin{array}{ccc}{i}_{\mathrm{<figure-callout\; id="1"\; label="B"\; filenames="HDA0000470584480000061.png"\; state="\{\{state\}\}">B</figure-callout>}1}...& i_{\mathrm{Bk}}+i_{\mathrm{\&Delta;k}}...& i_{\mathrm{Bn}}\end{array}\right]}^T+B^T\&times;{\stackrel{\&CenterDot;}{I}}_L$

(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 _{Δ k}, being obtained by formula (8), topological branch road occurs that wrong rear branch current does not all meet and imposes a condition, and difference and Topology Error branch current and current related over the ground.

${\stackrel{\&CenterDot;}{I}}_b^{\&prime;}=\left[\begin{array}{cc}{T}_{(m-1)\&times;\mathrm{<figure-callout\; id="0"\; label="m"\; filenames="HDA0000470584480000021.png,HDA0000470584480000022.png"\; state="\{\{state\}\}">m</figure-callout>}}& 0\\ 0& T_{(l+1-m)\&times;(n-m)}\end{array}\right]\&times;{\left[\begin{array}{ccc}{i}_{\mathrm{<figure-callout\; id="1"\; label="B"\; filenames="HDA0000470584480000061.png"\; state="\{\{state\}\}">B</figure-callout>}1}...& i_{\mathrm{Bk}}-i_{\mathrm{\&Delta;k}}...& i_{\mathrm{Bn}}\end{array}\right]}^T+B^T\&times;{\stackrel{\&CenterDot;}{I}}_L$

If the topological state of closed chord is for disconnecting, chord endpoint node Injection Current will be affected, cause branch current in loop not meet and impose a condition, this difference and chord are current related, and there is less difference in the branch current being positioned in road 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 between two buses, has 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, known according to formula (9), between the branch current calculated value between two buses and measured value, all there is difference, and difference and branch road k over the ground admittance electric current and place loop current relevant.

${\stackrel{\&CenterDot;}{I}}_b^{\&prime;}=\left[\begin{array}{cc}{T}_{m-\&times;m}& T_{m\&times;(n-m)}\\ T_{s\&times;m}^{\&prime;}& T_{s\&times;(n-m)}^{\&prime;}\\ T_{(l-s-m)\&times;m}& T_{(l-s-m)\&times;(n-m)}\end{array}\right]\&times;{\left[\begin{array}{cccc}{i}_{\mathrm{<figure-callout\; id="1"\; label="B"\; filenames="HDA0000470584480000061.png"\; state="\{\{state\}\}">B</figure-callout>}1}...& i_{\mathrm{Bk}}-i_{\mathrm{\&Delta;k}}...& i_{\mathrm{Bu}}+i_{\mathrm{\&Delta;k}}...& i_{\mathrm{Bu}}\end{array}\right]}^T+{\left[\begin{array}{ccc}{B}_{L\&times;(m-1)}& B_{L\&times;s}^{\&prime;}& B_{L\&times;(l+1-s-m)}\end{array}\right]}^T\&times;{\stackrel{\&CenterDot;}{I}}_L$

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 ε ₁, and branch current in this loop do not meet and imposes a condition, and this chord is actual is closure.Certain tree disconnects, but its Current calculation value is greater than ε ₁, and all branches electric current that on road, this tree props up after endpoint node 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 ε ₁, and in system road, all branches electric current after this branch road does not meet and imposes a condition, and this branch road is real in disconnecting.

Step a3: if branch road closure, its calculated value is less than ε ₁, but after by its branch road, admittance electric current deducts over the ground, node current and increase, 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 ε ₁and closed, but branch current measured value between two buses 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 end

path matrix T and return-Zhi incidence matrix B, return branch Current calculation module, recalculates

and again judge whether to exist Topology Error.For circuit breaker switch state is closed, actual disconnection and circuit breaker switch state disconnect and actual closed situation, more new node Injection Current matrix only need to upgrade the node Injection Current measured value of prop up/branch road endpoint node of wrongheaded chord/tree.For the wrongheaded situation of two female wiring, more new node Injection Current matrix

refer to that renewal 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, reality disconnects and circuit breaker switch state disconnects and actual closed situation, and isolating switch is revised as to actual open/close state, then upgrades path matrix T and return-Zhi incidence matrix B.For the wrongheaded situation of two female wiring, according to interconnection switch virtual condition, upgrade path matrix T and return-Zhi incidence matrix B.

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.Owing to comprising chord electric current and node current in road-loop equation, 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, and node Injection Current sum is greater than ε ₂.According to formula (7), occur all having difference between the branch current calculated value of bad data node and measured value, 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), between the branch current calculated value in loop and measured value, 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 row of B).

${\stackrel{\&CenterDot;}{I}}_b^{\&prime;}=T\&times;{\stackrel{\&CenterDot;}{I}}_N+B^T\&times;{\left[\begin{array}{ccc}{i}_{\mathrm{<figure-callout\; id="1"\; label="L"\; filenames="HDA0000470584480000061.png"\; state="\{\{state\}\}">L</figure-callout>}1}...& i_{\mathrm{Lk}}+\mathrm{\&Delta;i}...& i_{\mathrm{Lt}}\end{array}\right]}^T$

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

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

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

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, and bad data appears in this node 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, bad data appears in the chord electric current in this loop, props up the difference of Current calculation value and measured value revise 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 revised.

After bad data correction, return branch Current calculation module, recalculates

until meeting, all branch current measured values 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 incidence matrix, 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, comprises 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 matrix, T is the path matrix being formed by power network topology,

for node Injection Current matrix, B is the return-Zhi incidence matrix by each tree electric current and branch current orientation determination in the fundamental circuit of power network topology, for the chord current measurement value matrix being formed by the chord in branch road.

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 ε ₁, and in the residing loop of described chord, the branch current measured value of any branch road does not meet and imposes a condition, and described chord reality, in closure state, is upgraded node Injection Current, path matrix and the return-Zhi incidence matrix of described chord end, returns to step 2.

The node Injection Current that upgrades chord end adopts formula i _bk'=i _bk+ i _{Δ k}.Wherein, i _bk' be the node Injection Current of the chord end after upgrading, i _bkfor the node Injection Current of the chord end before upgrading, i _{Δ k}for described chord over the ground admittance electric current and

j is imaginary unit,

for the susceptance of described chord, with

be respectively the voltage of described chord two end nodes.Due to the misjudgment of chord state, therefore revise chord state, and upgrade path matrix and return-Zhi incidence matrix according to amended chord state.

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 value ₁, and the branch current measured value that on road, this tree props up all branches after endpoint node do not meet and imposes a condition, described tree Zhi Shiji is in closure state, upgrade a tree end node Injection Current, path matrix and time-Zhi incidence matrix, return to step 2.

The node Injection Current that upgrades a tree end adopts formula i _bk'=i _bk+ i _{Δ k}.Wherein, i _bk' prop up the node Injection Current of end, i for the tree after upgrading _bkfor the tree before upgrading props up the node Injection Current of end, i _{Δ k}for described tree prop up over the ground admittance electric current and

j is imaginary unit,

the susceptance propping up for described tree,

with be respectively the voltage of tree two end node.Due to a tree state misjudgment, therefore revise a tree state, and prop up state according to amended tree and upgrade path matrix and 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 ε ₁, and the branch current of all branch roads after the above branch road of road do not meet and imposes a condition, and described branch road reality is in off-state, upgrades node Injection Current, path matrix and the return-Zhi incidence matrix of branch road end, returns to step 2.

The node Injection Current that upgrades branch road end adopts formula i _bk'=i _bk-i _{Δ k}.Wherein, i _bk' be the node Injection Current of the branch road end after upgrading, i _bkfor the node Injection Current of the branch road end before upgrading, i _{Δ k}for described branch road over the ground admittance electric current and

j is imaginary unit,

for the susceptance of described branch road,

with

be respectively the voltage of branch road two end nodes.Due to a line state misjudgment, therefore revise a line state, and upgrade path matrix and return-Zhi incidence matrix according to amended line state.

Sub-step A4: for the branch road in closure state, if described branch current calculated value is less than the first setting threshold ε ₁, 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, and 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 affects the result of calculation of node Injection Current sum over the ground.If this branch road is closed, when computing node Injection Current sum, the electric current of admittance over the ground (negative value) of this branch road is counted, cause 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 measured value are all greater than the first setting threshold ε ₁and described branch road is in closure state, but the branch current measured value connecting between two buses of described branch road does not meet and imposes a condition, described branch road bus connection judgment mistake, renewal can be carried out node Injection Current, path matrix and the return-Zhi incidence matrix that the branch road of grid switching operation is connected with bus, returns 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 carrying out the node Injection Current before node updates that the branch road reality of grid switching operation is connected with bus, i _bv' for 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 _{Δ k}for can carry out grid switching operation branch road the electric current of admittance over the ground and

j is imaginary unit,

for carrying out the susceptance of the branch road of grid switching operation,

with be respectively the voltage of branch road two end nodes that can carry out grid switching operation.Owing to the branch road of grid switching operation can being carried out and change has occurred the connection status of bus, therefore can carry out the branch road of grid switching operation and the connection status of bus is upgraded path matrix and return-Zhi incidence matrix according to reality.

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 network

and in road, there is power supply node or load bus, branch current measured value after described power supply node or load bus does not meet and imposes a condition, there is bad data 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 the Injection Current of node i in electrical network, n is node number in electrical network, ε ₂it is the second setting threshold.The node Injection Current of revising power supply node or load bus adopts 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 setting bar branch road of the absolute difference maximum of the measured value of branch current and calculated value, by the measured value of branch current of setting bar branch road and the average of the difference of calculated value selected, with the node Injection Current sum of power supply node or the load bus node Injection Current as described this power supply node or load bus.

Sub-step B2: if there is a loop, branch current measured value in this loop does not meet and imposes a condition, there is bad data in the chord current measurement value in this loop, prop up difference and this chord current measurement value sum of Current calculation value and measured value with the tree in loop, described chord place, the chord current measurement value of replacing this chord, then returns 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 returns 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 that bus B2 and B7 can grid switching operations.Wherein, system power supply S _n=100MVA, U _n=220KV, ${\stackrel{\&CenterDot;}{I}}_{\mathrm{LN}}=(0.223+j0.138)\mathrm{kA},$ ε ₁=(0.01785+j0.0111)kA。

Formula (5) is verified, its branch road over the ground admittance is B/2=1.623 × 10 ^-4s, arranges posterior nodal point Injection Current suc as formula shown in (11) according to mentioned above principle, and loop current is i _l9=(0.43628-j0.216385) kA, result of calculation as shown in Figure 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 Injection 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, ε ₂=(1.255+j0.659)) × 10 ^-2kA, ε ₃=(2.478+j1.733) × 10 ^-3kA, the branch road after L1 does not all meet and imposes a condition, and L1 Current calculation value is greater than ε ₁, therefore judge that branch road L1 is actual in closed.Revise its topology information, T, B matrix and the node Injection Current after renewal is suc as formula shown in (2), (4), (11), and result of calculation as 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, judges branch road L4 metric data mistake, directly utilizes 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 as shown in Figure 6.This system 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, ε ₂=(1.2554+j0.6592) × 10 ^-2kA, ε ₃=(2.478+j1.733)) × 10 ^-3kA, disconnected branches L6 calculates electric current and is greater than ε ₁, and in road, the branch current behind its loop, place and loop does not all meet and imposes a condition, determine branch road L6 actual be closure.Revise after topology information, T, B are suc as formula shown in (2), (4), and node Injection Current is formula (16), and 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 ε ₁, but node Injection Current sum does not meet Kirchhoff's theorem, and after 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 node Injection Current and revising, result is suc as formula (17), and after calculating by road-loop equation, as shown in Figure 9, its branch current all meets and imposes a condition result, 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), and result of calculation is as Figure 11.

Analysis Figure 11 is known, and branch road L6 is greater than setting threshold ε ₁, not meeting and impose a condition but carry out branch current between two bus B2, the B7 of grid switching operation after L6, its difference and loop, branch road L6 place and this line-to-ground admittance difference between current approach, and judge L6 bus connection topology information mistake.Revise topology information, T, B matrix and the node Injection Current after renewal is suc as formula shown in (2), (4), (11), and 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 are suc as formula (2), (4), and node Injection Current, suc as formula (20), is ε according to data threshold value value ₂=(1.676+j0.9734) × 10 ^-2kA, ε ₃=(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 ε ₁, and after its endpoint node, branch current does not meet and imposes a condition, and therefore judges that branch road L6 is real in disconnecting.

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

Revise after the topology information of branch road L6, as shown in Figure 6, T, B matrix are suc as formula shown in (14) for system road, and node Injection 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, and as shown in figure 14, wherein solid triangle arrow mark must be chord for system architecture and pavement marker, and all the other branch roads are tree.The jot definite value of branch road is

therefore ε ₁=(0.021544+j0.012933) kA.More for interstitial content, the network of wiring complexity, can carry out local topology misidentification, herein only take two localized networks of Figure 14 institute mark as example.

(1) situation that many places bad data exists.

With node for the localized network of terminal as shown in figure 15.Its T, B matrix are suc as formula shown in (22), and analyze according to formula (6), all the other branch currents of node Injection Current enabled node and with this node Injection Current equivalence (as in loop, remove its place loop current impact), the value node Injection Current such as this localized network, shown in (23), and chord current i ₂₆=(0.6675+j0.9609) kA, i ₂₇=(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 ε ₂=(4.3+j6.4) × 10 ^-2kA, ε ₃=(6.452+j9.652) × 10 ^-3kA, node

total output current

all branches electric current is all greater than ε ₁, without Topology Error.According to localized network Kirchhoff's theorem, with node Injection Current and absolute difference be greater than ε ₂, branch road 19,20,25 electric currents all do not meet and impose a condition, wherein, and node

neither load bus, neither power supply node, decision node

there is difference in Injection Current.Consider that chord electric current also may be wrong, can not be directly with Kirchhoff's theorem correction node Injection Current.Relatively cause the factor of each line current difference, can obtain branch road 19 differences and deduct branch road 25 differences, be node

the error amount of Injection Current, uses this difference to revise to obtain i to Injection Current ₁₂=(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 Injection Current still do not meet Kirchhoff's theorem, but both differences equate.Tentatively judge branch road 26 current error, use the electric current difference of branch road 19 to revise to obtain i to it ₂₆=1.33495+j1.92183KA, then, uses revised measuring value to calculate, and 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 improve the 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).According to formula (6) must this localized network node Injection Current suc as formula shown in (25), result of calculation is as Figure 20.

According to the known node of Figure 19 for road starting point, irrelevant with other node of one's respective area, need carry out separately Kirchhoff's theorem verification.This region ε ₃=(7.988+j6.904) × 10 ^-3kA; For node

ε ₂=(4.01+j3.45) × 10 ^-3kA, all the other node summation threshold values are ε ₂=(0.64+j1.59) × 10 ^-2kA.Analyze Figure 20, the measured value of known chord 29 is greater than ε ₁, be not inconsistent with topology information, and branch current in this loop all do not meet and imposes a condition, therefore, judge branch road 29 Topology Errors.Change B matrix the first row in formula (24) into [1 11 0].Revise after topology, result of calculation as shown in figure 21, from figure, can find out by data, and its branch current meets and is greater than ε ₁and meet and impose a condition, and this localized network node Injection Current meets Kirchhoff's theorem, now, do not have Topology Error and bad data.

The above; only for preferably embodiment of the present invention, but protection scope of the present invention is not limited to this, is anyly familiar with in technical scope that those skilled in the art disclose in the present invention; the variation that can expect easily or replacement, within all should being encompassed in protection scope of the present invention.Therefore, protection scope of the present invention should be as the criterion with the protection domain of claim.

Claims (9)

1. the power network topology misidentification system based on road-loop equation, is characterized in that described system comprises 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 result output module are 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 is used 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 topology error identification module;

Described branch current computing module is described the grid topology data of topological structure of electric and asks for branch current calculated value for generating, 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 grid topology data and interdependent node Injection Current, and the data after upgrading are sent to branch current computing module; In the time that mistake does not appear in power network topology, 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; In the time there is bad data, revise relevant bad data, and revised data are sent to branch current computing module; In the time not there is not bad 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, comprises 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.

3. discrimination method according to claim 2, described in it is characterized in that, ask for branch current calculated value and adopt formula:

${\stackrel{\&CenterDot;}{I}}_b^{\&prime;}=T\&times;{\stackrel{\&CenterDot;}{I}}_N+B^T\&times;{\stackrel{\&CenterDot;}{I}}_L;$

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.

4. discrimination method according to claim 3, is characterized in that described 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 ε ₁, and in the residing loop of described chord, the branch current measured value of any branch road does not meet and imposes a condition, and described chord reality, in closure state, is upgraded node Injection Current, path matrix and the return-Zhi incidence matrix of described chord end, returns to step 2;

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 value ₁, and the branch current measured value that on road, this tree props up all branches after endpoint node do not meet and imposes a condition, described tree Zhi Shiji is in closure state, upgrade a tree end node Injection Current, path matrix and time-Zhi incidence matrix, 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 ε ₁, and the branch current measured value of all branch roads after the above branch road of road do not meet and imposes a condition, and described branch road reality is in off-state, upgrades node Injection Current, path matrix and the return-Zhi incidence matrix of branch road end, returns to step 2;

Sub-step A4: for the branch road in closure state, if described branch current calculated value is less than the first setting threshold ε ₁, and after the electric current of admittance over the ground of described branch road is deducted, node Injection Current sum increases, and branch road topology information is correct, and 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 calculated value of described branch road and branch current measured value are all greater than the first setting threshold ε ₁and described branch road is in closure state, but the branch current measured value connecting between two buses of described branch road does not meet and imposes a condition, described branch road bus connection judgment mistake, renewal can be carried out node Injection Current, path matrix and the return-Zhi incidence matrix that the branch road of grid switching operation is connected with bus, returns to step 2;

The node Injection Current of described renewal chord/tree end adopts formula i _bk'=i _bk+ i _{Δ k};

The node Injection Current of described renewal branch road end adopts formula i _bk'=i _bk-i _{Δ k};

Wherein, i _bk' be 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 $\left\{\begin{array}{c}{i}_{\mathrm{Bu}}^{\&prime;}=i_{\mathrm{Bu}}-i_{\mathrm{\&Delta;k}}\\ i_{\mathrm{Bv}}^{\&prime;}=i_{\mathrm{Bv}}+i_{\mathrm{\&Delta;k}}\end{array}\right.;$

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

I _bv' for 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 _{Δ k}for 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;

with be respectively chord/tree/branch road/can carry out the voltage of branch road two end nodes of grid switching operation.

5. discrimination method according to claim 4, is characterized in that described the first setting threshold ε ₁for branch road rated current

0.08 times,

6. discrimination method according to claim 3, is characterized in that described 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 sums

and in road, there is power supply node/load bus, branch current measured value after described power supply node/load bus does not meet and imposes a condition, there is bad data in the node Injection Current of described power supply node/load bus, the node Injection Current of revising power supply node/load bus, then returns to step 2;

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

Or, the node Injection Current of described correction power supply node/load bus is, select in the branch road after described power supply node/load bus, the setting bar branch road of the absolute difference maximum of the measured value of branch current and calculated value, by the branch current measured value of setting bar branch road of selecting and the average of the difference of calculated value, with the node Injection Current sum of the power supply node/load bus node Injection Current as 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;

ε ₂it is the second setting threshold;

Sub-step B2: if there is a loop, branch current measured value in described loop does not meet and imposes a condition, there is bad data in the chord current measurement value in described loop, prop up difference and the described chord current measurement value sum of Current calculation value and measured value with the tree in loop, described chord place, the chord current measurement value of replacing described chord, then returns 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 returns to step 2.

7. discrimination method according to claim 6, is characterized in that described the second setting threshold ε ₂=k × n × 0.2% × max{|i _bi|;

Wherein, k is safety factor;

N is summing junction number;

Max{|i _bi| be summing junction Injection Current absolute value maximal value.

8. according to the discrimination method described in any one claim in claim 4-7, described in it is characterized in that, impose a condition as the error of calculation of branch current measured value and branch current calculated value | i _lk-i _lk' | < ε ₃;

Wherein i _lkfor branch current measured value;

I _lk' be branch current calculated value;

ε ₃it is the 3rd setting value threshold value.

9. discrimination method according to claim 8, is characterized in that described the 3rd setting threshold ε ₃value is 0.3% of maximum branch current absolute value, i.e. ε ₃=0.3% × | max{i _lk|; Wherein, max{i _lkit is maximum branch current.

Images