Disclosure of Invention
The purpose of the invention is: according to the running state of the equipment, a load transfer candidate measure set is identified on line, active adjusting measures are added on the basis of load transfer of the equipment capable of being put into operation, the adjusting amount and the pressure load amount of the generator are reduced, and the economical efficiency of overload auxiliary decision measures is improved.
Specifically, the invention is realized by adopting the following technical scheme, which comprises the following steps:
1) the overload safety margin of the power grid under the current state is smaller than the set threshold value etacr.1And the overload safety margin under the expected fault is less than the set threshold value etacr.1The equipment is added into the overload equipment set, and the minimum value of the overload safety margin of the equipment under the expected fault is smaller than the set threshold value etacr.2If the overload equipment is concentrated with overload equipment, entering step 2); whether or notThen, the method is ended;
the equipment refers to lines and transformers;
2) if the switch knife switch group directly connected with the equipment in the shutdown and overhaul finish state is closed, the equipment can be put into operation, and the node directly connected with the equipment and the node directly connected with the overload equipment centralized equipment belong to the same electric island, the equipment is added into the equipment capable of being put into operation and centralized, and if the equipment capable of being put into operation and centralized with the equipment capable of being put into operation, the step 3 is carried out; otherwise, entering step 6);
3) respectively aiming at each commissioning device in the commissioning device set, adopting direct current power flow to estimate the overload safety margin of each device in the overload device set after the commissioning device is commissioned, calculating the comprehensive performance index of the commissioning device, and if the overload safety margins of all the devices in the overload device set are greater than a specified threshold value etathres.onEntering step 4); otherwise, entering step 5);
eta ofthres.on>ηcr.1;
4) After the alternating current power flow computing equipment is put into operation, the overload safety margin of each centralized equipment of the overload equipment is calculated, the comprehensive performance index of the operable equipment is computed, and if the overload safety margin of the centralized overload equipment is smaller than eta, the overload safety margin is calculatedcr.1Step 5) is entered; otherwise, the equipment capable of being put into operation with the maximum comprehensive performance index is taken as a final control measure, and the method is ended;
5) selecting the commissioning equipment with the comprehensive performance index larger than the given threshold value as the commissioning equipment to be checked, and entering the step 6);
6) if the commissionable equipment to be checked exists, determining the maximum adjustment quantity of the generator and the load active adjustment measure for solving the overload problem on the basis of the measure transfer of each commissioning equipment to the load, or directly determining the maximum adjustment quantity of the generator and the load active adjustment measure for solving the overload problem;
7) forming a generator and load adjustment scheme according to the maximum adjustment amount of the generator and load active adjustment measures and the calculation precision of active adjustment, if the commissionable equipment to be checked exists, combining the commissionable equipment to be checked with the generator and the load adjustment scheme to obtain a calculation scheme needing alternating current power flow checking, otherwise, directly using the generator and the load adjustment scheme as the calculation scheme needing alternating current power flow checking, sequencing the calculation schemes according to the sequence of the control cost of the control measures from small to large, performing alternating current power flow checking aiming at no fault and a key fault set on each scheme through parallel calculation, and if the overload safety margin is larger than eta, if the overload safety margin is obtainedcr.1If the calculation scheme is the same as the calculation scheme, stopping parallel calculation, outputting the calculation scheme as a final control measure and finishing the method; otherwise, the method is ended.
The technical scheme is further characterized in that: in the step 1), different limit values are adopted to calculate the overload safety margins of the jth equipment under the current state and the expected fault of the power grid:
when the jth equipment is a line, calculating the overload safety margin eta by the formula (1)j:
<math>
<mrow>
<msub>
<mi>η</mi>
<mi>j</mi>
</msub>
<mo>=</mo>
<mrow>
<mo>(</mo>
<mn>1</mn>
<mo>-</mo>
<mfrac>
<msub>
<mi>I</mi>
<mi>L</mi>
</msub>
<msub>
<mi>I</mi>
<mi>P</mi>
</msub>
</mfrac>
<mo>)</mo>
</mrow>
<mo>×</mo>
<mn>100</mn>
<mo>%</mo>
<mo>-</mo>
<mo>-</mo>
<mo>-</mo>
<mrow>
<mo>(</mo>
<mn>1</mn>
<mo>)</mo>
</mrow>
</mrow>
</math>
Wherein, when calculating the overload safety margin of the line under the current state of the power grid, ILIs the current at the end with larger current at the two ends of the line under the current state, IPIs normalLine allowable current under operating conditions; when calculating the overload safety margin of the line under the expected fault of the power grid, ILTo predict the current at the end of the line with the larger current at both ends under fault, IPAllowing current for line operation under accident conditions;
when the jth equipment is a transformer, respectively calculating overload safety margins eta of windings of the transformer by a formula (2)j,wThe overload safety margin of the transformer equipment is the minimum value of the overload safety margin in each winding of the transformer:
<math>
<mrow>
<msub>
<mi>η</mi>
<mrow>
<mi>j</mi>
<mo>,</mo>
<mi>w</mi>
</mrow>
</msub>
<mo>=</mo>
<mrow>
<mo>(</mo>
<mn>1</mn>
<mo>-</mo>
<mfrac>
<mrow>
<msub>
<mi>S</mi>
<mi>T</mi>
</msub>
<mo>/</mo>
<msub>
<mi>U</mi>
<mi>T</mi>
</msub>
</mrow>
<mrow>
<msub>
<mi>S</mi>
<mi>P</mi>
</msub>
<mo>/</mo>
<msub>
<mi>U</mi>
<mrow>
<mi>N</mi>
<mo>,</mo>
<mi>w</mi>
</mrow>
</msub>
</mrow>
</mfrac>
<mo>)</mo>
</mrow>
<mo>×</mo>
<mn>100</mn>
<mo>%</mo>
<mo>-</mo>
<mo>-</mo>
<mo>-</mo>
<mrow>
<mo>(</mo>
<mn>2</mn>
<mo>)</mo>
</mrow>
</mrow>
</math>
wherein w denotes the different windings of the transformer, UN,wThe rated voltage of each winding; when calculating the overload safety margin of the transformer under the current state of the power grid, STAnd UTApparent power and voltage of the current state of the winding, SPIs the allowable capacity of the transformer under normal conditions; overload of transformer when calculating expected failure of power gridAt a margin of safety, STAnd UTTo predict the apparent power and voltage of the winding under fault, SPIs the allowable capacity of the transformer in an accident condition.
The technical scheme is further characterized in that: calculating the comprehensive performance index of the commissioning equipment in the step 3) and the step 4) through a formula (3):
<math>
<mrow>
<msub>
<mi>p</mi>
<msub>
<mi>i</mi>
<mi>L</mi>
</msub>
</msub>
<mo>=</mo>
<munderover>
<mi>Σ</mi>
<mrow>
<mi>j</mi>
<mo>=</mo>
<mn>1</mn>
</mrow>
<mi>N</mi>
</munderover>
<mo>[</mo>
<msub>
<mi>S</mi>
<mrow>
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<mi>i</mi>
<mi>L</mi>
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</msub>
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<mi>η</mi>
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</msub>
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</mrow>
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<munderover>
<mi>Σ</mi>
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<mi>Σ</mi>
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<msub>
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</munderover>
<mo>[</mo>
<msub>
<mi>S</mi>
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<msub>
<mi>i</mi>
<mi>L</mi>
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<mi>k</mi>
</mrow>
</msub>
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<mo>(</mo>
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<mo>-</mo>
<msub>
<mi>η</mi>
<mrow>
<msub>
<mi>j</mi>
<mn>1</mn>
</msub>
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<mi>k</mi>
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</mrow>
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<mo>-</mo>
<mo>-</mo>
<mo>-</mo>
<mrow>
<mo>(</mo>
<mn>3</mn>
<mo>)</mo>
</mrow>
</mrow>
</math>
wherein i
L1,2, L being the total number of commissionable devices,
is the ith
LThe comprehensive performance index of each commissioning device, N is the total number of overload devices in the current state, eta
jFor the overload safety margin of the jth overload device,
is the ith
LThe overload safety margin variation of the jth overload device after the commissioning of the commissionable device; w is the total number of overload safety critical faults, N
kFor the total number of overloaded devices at the kth overloaded safety-critical fault,
for the kth overload safety critical fault at the jth
1The overload safety margin of an individual overload device,
is the ith
LJ < th > overload safety critical fault after commissioning of commissionable equipment
1The overload safety margin variation of each overload device.
The technical scheme is further characterized in that: the step of determining the maximum adjustment quantity of the generator and the load active adjustment measure for solving the overload problem in the step 6) is divided into four steps:
step one, if the commissionable equipment to be checked exists, calculating the comprehensive performance index of the active adjustment measure on overload under the current state and the expected fault according to the overload safety margin of the equipment after commissioning by a formula (4); otherwise, the comprehensive performance index of the active power adjustment measure on the overload under the current state and the expected fault is directly calculated through a formula (4):
<math>
<mrow>
<msub>
<mi>w</mi>
<msub>
<mi>i</mi>
<mi>M</mi>
</msub>
</msub>
<mo>=</mo>
<munderover>
<mi>Σ</mi>
<mrow>
<mi>j</mi>
<mo>=</mo>
<mn>1</mn>
</mrow>
<mi>N</mi>
</munderover>
<mo>[</mo>
<msub>
<mi>λ</mi>
<mrow>
<msub>
<mi>i</mi>
<mi>M</mi>
</msub>
<mo>,</mo>
<mi>j</mi>
</mrow>
</msub>
<mrow>
<mo>(</mo>
<mn>1</mn>
<mo>-</mo>
<msub>
<mi>η</mi>
<mi>j</mi>
</msub>
<mo>)</mo>
</mrow>
<mo>]</mo>
<mo>+</mo>
<munderover>
<mi>Σ</mi>
<mrow>
<mi>k</mi>
<mo>=</mo>
<mn>1</mn>
</mrow>
<mi>W</mi>
</munderover>
<munderover>
<mi>Σ</mi>
<mrow>
<msub>
<mi>j</mi>
<mn>1</mn>
</msub>
<mo>=</mo>
<mn>1</mn>
</mrow>
<msub>
<mi>N</mi>
<mi>k</mi>
</msub>
</munderover>
<mo>[</mo>
<msub>
<mi>λ</mi>
<mrow>
<msub>
<mi>i</mi>
<mi>M</mi>
</msub>
<mo>,</mo>
<msub>
<mi>j</mi>
<mn>1</mn>
</msub>
<mo>.</mo>
<mi>k</mi>
</mrow>
</msub>
<mrow>
<mo>(</mo>
<mn>1</mn>
<mo>-</mo>
<msub>
<mi>η</mi>
<mrow>
<msub>
<mi>j</mi>
<mn>1</mn>
</msub>
<mo>.</mo>
<mi>k</mi>
</mrow>
</msub>
<mo>)</mo>
</mrow>
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<mo>-</mo>
<mo>-</mo>
<mo>-</mo>
<mrow>
<mo>(</mo>
<mn>4</mn>
<mo>)</mo>
</mrow>
</mrow>
</math>
wherein i
M1,2, M being the total number of active adjustment measures,
is the ith
MThe comprehensive performance index of active adjustment measures, N is the total number of overload devices in the current state, eta
jFor the overload safety margin of the jth overload device,
is the ith
MThe active sensitivity of the active adjustment measure to the jth overload device; w is the total number of overload safety critical faults, N
kFor the total number of overloaded devices at the kth overloaded safety-critical fault,
for the kth overload safety critical fault at the jth
1The overload safety margin of an individual overload device,
is the ith
MActive adjustment measure to the j th fault under the k th fault
1The active sensitivity of the individual devices;
secondly, taking the active adjustment measures with the comprehensive performance indexes larger than the set threshold value as alternative measures, selecting the alternative measures with the comprehensive performance indexes negative as a power transmission queue, and increasing the output of the generator nodes in the queue while reducing the active of the load nodes; selecting alternative measures with positive comprehensive performance indexes as a power receiving queue, and reducing the output of generator nodes in the queue;
thirdly, sequencing the alternative measures in the power transmission queue and the power receiving queue according to the priority of the control measure from high to low, sequencing the alternative measures with the same control priority according to the cost performance index from large to small, wherein the cost performance index is calculated by a formula (5):
wherein,
is the ith
MThe adjustment cost of unit power of active adjustment measures;
and fourthly, taking the maximum value of the maximum adjustment amount of the power transmission queue and the maximum adjustment amount of the power receiving queue as the maximum adjustment amount for determining the calculation scheme.
The technical scheme is further characterized in that: in the step 7), according to different adjustment quantity requirements, sequentially adjusting each node of the power transmission queue and the power receiving queue according to the adjustment sequence of the control measures determined in the step 6), so that the control cost is minimum, and the frequency deviation of the system caused by the imbalance of the active power of the system meets the operation requirement, thereby obtaining a calculation scheme.
The invention has the following beneficial effects: the method can identify the load transfer candidate measure set on line, and adds active power adjusting measures on the basis of the load transfer measures to reduce the adjusting amount and the pressure load amount of the generator; and a generator and load adjustment scheme is formed according to the calculation precision of active adjustment, and alternating current power flow check is performed through parallel calculation, so that multiple rounds of iteration are avoided. Therefore, the power grid equipment overload assistant decision-making calculation method considering the load transfer measures can improve the economy of assistant decision-making measures and the calculation speed of overload assistant decisions.
Detailed Description
The invention is described in further detail below with reference to the figures and with reference to examples.
Step 1 in fig. 1 describes that the overload safety margin of the current state of the power grid is smaller than the set threshold value etacr.1And the overload safety margin under the expected fault is less than the set threshold value etacr.1The equipment is added into the overload equipment set, and the minimum value of the overload safety margin of the equipment under the expected fault is smaller than the set threshold value etacr.2If the overload equipment is concentrated with overload equipment, entering step 2); otherwise, the method is ended. The equipment refers to lines and transformers. Threshold eta of overload safety margincr.1The overload device is used for determining the current state of the power grid and the expected faults; threshold eta of overload safety margincr.2And the method is used for determining the expected faults of the comprehensive performance indexes participating in the calculation of the assistant decision measures.
And calculating the overload safety margin of the jth device under the current state and the expected fault of the power grid by adopting different limit values: when the jth equipment is a line, calculating the overload safety margin eta by the formula (1)j:
<math>
<mrow>
<msub>
<mi>η</mi>
<mi>j</mi>
</msub>
<mo>=</mo>
<mrow>
<mo>(</mo>
<mn>1</mn>
<mo>-</mo>
<mfrac>
<msub>
<mi>I</mi>
<mi>L</mi>
</msub>
<msub>
<mi>I</mi>
<mi>P</mi>
</msub>
</mfrac>
<mo>)</mo>
</mrow>
<mo>×</mo>
<mn>100</mn>
<mo>%</mo>
<mo>-</mo>
<mo>-</mo>
<mo>-</mo>
<mrow>
<mo>(</mo>
<mn>1</mn>
<mo>)</mo>
</mrow>
</mrow>
</math>
Wherein, when calculating the overload safety margin of the line under the current state of the power grid, ILIs the current at the end with larger current at the two ends of the line under the current state, IPAllowing current to the line under normal operating conditions; when calculating the overload safety margin of the line under the expected fault of the power grid, ILTo predict the current at the end of the line with the larger current at both ends under fault, IPAllowing current for line operation under accident conditions;
when the jth equipment is a transformer, respectively calculating overload safety margins eta of windings of the transformer by a formula (2)j,wThe overload safety margin of the transformer equipment is the minimum value of the overload safety margin in each winding of the transformer:
<math>
<mrow>
<msub>
<mi>η</mi>
<mrow>
<mi>j</mi>
<mo>,</mo>
<mi>w</mi>
</mrow>
</msub>
<mo>=</mo>
<mrow>
<mo>(</mo>
<mn>1</mn>
<mo>-</mo>
<mfrac>
<mrow>
<msub>
<mi>S</mi>
<mi>T</mi>
</msub>
<mo>/</mo>
<msub>
<mi>U</mi>
<mi>T</mi>
</msub>
</mrow>
<mrow>
<msub>
<mi>S</mi>
<mi>P</mi>
</msub>
<mo>/</mo>
<msub>
<mi>U</mi>
<mrow>
<mi>N</mi>
<mo>,</mo>
<mi>w</mi>
</mrow>
</msub>
</mrow>
</mfrac>
<mo>)</mo>
</mrow>
<mo>×</mo>
<mn>100</mn>
<mo>%</mo>
<mo>-</mo>
<mo>-</mo>
<mo>-</mo>
<mrow>
<mo>(</mo>
<mn>2</mn>
<mo>)</mo>
</mrow>
</mrow>
</math>
wherein w denotes the different windings of the transformer, UN,wThe rated voltage of each winding; when calculating the overload safety margin of the transformer under the current state of the power grid, STAnd UTApparent power and voltage of the current state of the winding, SPIs the allowable capacity of the transformer under normal conditions; when calculating the overload safety margin of the transformer under the expected failure of the power grid, STAnd UTTo predict the apparent power and voltage of the winding under fault, SPIs the allowable capacity of the transformer in an accident condition.
Step 2 in fig. 1 describes that if the switch knife switch group directly connected to the equipment in the shutdown and overhaul end state is closed, the equipment can be put into operation, and the node directly connected to the equipment and the node directly connected to the overload equipment centralized equipment belong to the same electrical island, the equipment is added to the commissionable equipment set, and if the commissionable equipment set is centralized with commissionable equipment, step 3 is entered); otherwise, go to step 6).
Step 3 in fig. 1 describes that, for each commissioning device in the commissioning device set, the dc power flow is used to estimate the overload safety margin of each device in the overload device set after the commissioning device is commissioned, and the overall performance index of the commissioning device is calculated, if the overload safety margins of all devices in the overload device set are greater than the specified threshold value ηthres.onWherein etathres.on>ηcr.1Entering step 4); otherwise, go to step 5). Threshold eta of overload safety marginthres.onFor determining a commissionable device that can completely eliminate the overload.
And (3) calculating the comprehensive performance index of the commissioning equipment on the overload under the current state and the expected fault by the formula (3):
<math>
<mrow>
<msub>
<mi>p</mi>
<msub>
<mi>i</mi>
<mi>L</mi>
</msub>
</msub>
<mo>=</mo>
<munderover>
<mi>Σ</mi>
<mrow>
<mi>j</mi>
<mo>=</mo>
<mn>1</mn>
</mrow>
<mi>N</mi>
</munderover>
<mo>[</mo>
<msub>
<mi>S</mi>
<mrow>
<msub>
<mi>i</mi>
<mi>L</mi>
</msub>
<mo>,</mo>
<mi>j</mi>
</mrow>
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<mi>η</mi>
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</msub>
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</mrow>
<mo>]</mo>
<mo>+</mo>
<munderover>
<mi>Σ</mi>
<mrow>
<mi>k</mi>
<mo>=</mo>
<mn>1</mn>
</mrow>
<mi>W</mi>
</munderover>
<munderover>
<mi>Σ</mi>
<mrow>
<msub>
<mi>j</mi>
<mn>1</mn>
</msub>
<mo>=</mo>
<mn>1</mn>
</mrow>
<msub>
<mi>N</mi>
<mi>k</mi>
</msub>
</munderover>
<mo>[</mo>
<msub>
<mi>S</mi>
<mrow>
<msub>
<mi>i</mi>
<mi>L</mi>
</msub>
<mo>,</mo>
<msub>
<mi>j</mi>
<mn>1</mn>
</msub>
<mo>.</mo>
<mi>k</mi>
</mrow>
</msub>
<mrow>
<mo>(</mo>
<mn>1</mn>
<mo>-</mo>
<msub>
<mi>η</mi>
<mrow>
<msub>
<mi>j</mi>
<mn>1</mn>
</msub>
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<mi>k</mi>
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<mo>-</mo>
<mrow>
<mo>(</mo>
<mn>3</mn>
<mo>)</mo>
</mrow>
</mrow>
</math>
wherein i
L1,2, L being the total number of commissionable devices,
is the ith
LThe comprehensive performance index of each commissioning device, N is the total number of overload devices in the current state, eta
jFor the overload safety margin of the jth overload device,
is the ith
LThe overload safety margin variation of the jth overload device after the commissioning of the commissionable device; w is the total number of overload safety critical faults, N
kFor the total number of overloaded devices at the kth overloaded safety-critical fault,
for the kth overload safety critical fault at the jth
1The overload safety margin of an individual overload device,
is the ith
LJ < th > overload safety critical fault after commissioning of commissionable equipment
1The overload safety margin variation of each overload device.
Step 4 in fig. 1 describes that the overload safety margin of each device in the overload device set after the ac power flow calculation device is put into operation is adopted, and the comprehensive performance index of the operable device is calculated, if the overload safety margin in the overload device set is smaller than ηcr.1Step 5) is entered; otherwise, the equipment capable of being put into operation with the maximum comprehensive performance index is taken as a final control measure, and the method is ended.
Step 5 in fig. 1 illustrates selecting a device having an overall performance indicator greater than a given threshold value as a commissionable device to be checked, and proceeding to step 6).
Step 6 in fig. 1 describes that if there is a commissionable device to be checked, the maximum adjustment amount of the generator and the load active adjustment measure for solving the overload problem is determined on the basis of the transfer of each commissioning device measure to the load, or else the maximum adjustment amount of the generator and the load active adjustment measure for solving the overload problem is directly determined. The step of determining the maximum adjustment quantity of the generator and the load active adjustment measure for solving the overload problem is divided into four steps:
step one, if the commissionable equipment to be checked exists, calculating the comprehensive performance index of the active adjustment measure on overload under the current state and the expected fault according to the overload safety margin of the equipment after commissioning by a formula (4); otherwise, the comprehensive performance index of the active power adjustment measure on the overload under the current state and the expected fault is directly calculated through a formula (4):
<math>
<mrow>
<msub>
<mi>w</mi>
<msub>
<mi>i</mi>
<mi>M</mi>
</msub>
</msub>
<mo>=</mo>
<munderover>
<mi>Σ</mi>
<mrow>
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<mn>1</mn>
</mrow>
<mi>N</mi>
</munderover>
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<mi>λ</mi>
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</msub>
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<mi>j</mi>
</mrow>
</msub>
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<mo>(</mo>
<mn>1</mn>
<mo>-</mo>
<msub>
<mi>η</mi>
<mi>j</mi>
</msub>
<mo>)</mo>
</mrow>
<mo>]</mo>
<mo>+</mo>
<munderover>
<mi>Σ</mi>
<mrow>
<mi>k</mi>
<mo>=</mo>
<mn>1</mn>
</mrow>
<mi>W</mi>
</munderover>
<munderover>
<mi>Σ</mi>
<mrow>
<msub>
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<mn>1</mn>
</msub>
<mo>=</mo>
<mn>1</mn>
</mrow>
<msub>
<mi>N</mi>
<mi>k</mi>
</msub>
</munderover>
<mo>[</mo>
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</msub>
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<msub>
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<mo>)</mo>
</mrow>
<mo>]</mo>
<mo>-</mo>
<mo>-</mo>
<mo>-</mo>
<mrow>
<mo>(</mo>
<mn>4</mn>
<mo>)</mo>
</mrow>
</mrow>
</math>
wherein i
M1,2, M being the total number of active adjustment measures,
is the ith
MThe comprehensive performance index of active adjustment measures, N is the total number of overload devices in the current state, eta
jFor the overload safety margin of the jth overload device,
is the ith
MThe active sensitivity of the active adjustment measure to the jth overload device; w is the total number of overload safety critical faults, N
kFor the total number of overloaded devices at the kth overloaded safety-critical fault,
for the kth overload safety critical fault at the jth
1The overload safety margin of an individual overload device,
is the ith
MActive adjustment measure to the j th fault under the k th fault
1The active sensitivity of the individual devices.
Secondly, taking the active adjustment measures with the comprehensive performance indexes larger than the set threshold value as alternative measures, selecting the alternative measures with the comprehensive performance indexes negative as a power transmission queue, and increasing the output of the generator nodes in the queue while reducing the active of the load nodes; and selecting an alternative measure with a positive comprehensive performance index as a power receiving queue, and reducing the output of the generator nodes in the queue.
Thirdly, sequencing the alternative measures in the power transmission queue and the power receiving queue according to the priority of the control measure from high to low, sequencing the alternative measures with the same control priority according to the cost performance index from large to small, and calculating the cost performance index through a formula (5):
wherein,
is the ith
MThe active power adjustment measures the adjustment cost of unit power.
And fourthly, taking the maximum value of the maximum adjustment amount of the power transmission queue and the maximum adjustment amount of the power receiving queue as the maximum adjustment amount for determining the calculation scheme.
Step 7 in fig. 1 describes that a generator and load adjustment scheme is formed according to the maximum adjustment amount of the generator and load active adjustment measures and the calculation accuracy of active adjustment, if there is a commissioning device to be checked, the commissioning device to be checked is combined with the generator and load adjustment scheme to obtain a calculation scheme requiring ac power flow checking, otherwise, the generator and load adjustment scheme are directly used as the calculation scheme requiring ac power flow checking, the calculation schemes are sorted according to the order of the control cost of the control measures from small to large, the schemes are checked for ac power flows without faults and key fault sets by parallel calculation, and if so, ac power flows of no fault and key fault sets are obtainedOverload safety margin greater than etacr.1If the calculation scheme is the same as the calculation scheme, stopping parallel calculation, outputting the calculation scheme as a final control measure and finishing the method; otherwise, the method is ended
And aiming at different adjustment quantity requirements, sequentially adjusting each node of the power transmission queue and the power receiving queue according to the adjustment sequence of the control measures determined in the step 6), so that the control cost is minimum, and the frequency deviation of the system caused by the imbalance of the active power of the system meets the operation requirement, thereby obtaining a calculation scheme.
Although the present invention has been described in terms of the preferred embodiment, it is not intended that the invention be limited to the embodiment. Any equivalent changes or modifications made without departing from the spirit and scope of the present invention also belong to the protection scope of the present invention. The scope of the invention should therefore be determined with reference to the appended claims.