Method and system for power out-of-limit processing of multi-zone time-series production simulation tie lines

Abstract

The application discloses a kind of multi-region time sequence production simulation tie line power over-limit processing method and system, comprising: obtaining the comprehensive load curve of each subarea and the start-up information of each subarea unit at each time;According to the comprehensive load curve and start-up information, direct current power flow calculation is carried out, to determine the ac tie line power of each tie line at each time;For any tie line, the ac tie line power of any tie line at each time is compared with the tie line power threshold corresponding to the any tie line, to determine the time when the ac tie line power corresponding to the any tie line is over-limit;For any target tie line with ac tie line power over-limit, according to the start-up information corresponding to the time when the ac tie line power corresponding to any target tie line is over-limit, the adjustment amount of generator power is minimized as the optimization target, to adjust the subarea unit output, so that there is no ac tie line power over-limit time for any target tie line.

Description

Technical Field

[0001] This invention relates to the field of power grid planning and operation technology, and more specifically, to a method and system for handling power over-limit processing of multi-region time-series production simulation tie lines. Background Technology

[0002] Due to limitations in the thermal capacity of transmission lines and system stability, the power transmission capacity of transmission lines is restricted. The phenomenon where the transmitted power reaches or exceeds this capacity limit is called congestion. In power system operation, various uncertainties exist, such as the uncertainty of load forecasting, the randomness of generation plans, the randomness of power equipment (generators, lines, transformers, etc.) failures, and the uncertainty of electricity prices. These factors all contribute to the uncertainty of transmission congestion. Based on deterministic information such as the power system topology, electrical parameters, operating parameters, and load levels, power flow analysis can be used to determine whether congestion has occurred.

[0003] Time-series production simulation arranges the output of each generator unit step by step in hourly increments under a certain load. It is currently widely used both domestically and internationally for power system dispatching, power generation planning, power balance calculations, and renewable energy consumption calculations. Time-series production simulation can be divided into short-term and medium-to-long-term simulations based on the simulation duration: short-term simulations last from several hours to tens of hours, providing guidance for daily or weekly power system operation; medium-to-long-term simulations last from several months to several years, simulating long-term generator start-up arrangements to provide power balance, energy balance, and peak-shaving balance results for grid planning, thus providing a basis for power source and grid planning. Summary of the Invention

[0004] This invention proposes a method and system for handling power over-limit issues in multi-region time-series production simulation tie lines, in order to solve the problem of how to achieve tie line power over-limit handling that balances efficiency and accuracy.

[0005] To address the aforementioned problems, according to one aspect of the present invention, a method for handling power over-limit processing of multi-region timing production simulation tie lines is provided, the method comprising:

[0006] Obtain the comprehensive load curve of each zone and the unit start-up information of each zone at each time.

[0007] DC power flow calculations are performed based on the comprehensive load curve and start-up information to determine the AC tie-line power of each tie line at each moment;

[0008] For any tie line, compare the AC tie line power of that tie line at each time with the tie line power threshold corresponding to that tie line to determine the time when the AC tie line power of that tie line exceeds the limit.

[0009] For any target tie line where the AC tie line power exceeds the limit, based on the start-up information corresponding to the moment when the AC tie line power exceeds the limit for any target tie line, the output of the zoned units is adjusted with the goal of minimizing the sum of squares of the generator power adjustment amount, so that there is no moment when the AC tie line power exceeds the limit for any target tie line.

[0010] Preferably, the method further includes:

[0011] Obtain the maintenance schedule for each zone's generating units, and determine the permissible operating time for each zone's generating units based on the maintenance schedule for each zone's generating units;

[0012] The load curves, load reserve rates, emergency reserve capacity, and DC power transmission of each zone are obtained and superimposed onto the load curves according to the reliability of the new energy output forecast to obtain the comprehensive load curves of each zone.

[0013] The start-up schedule for each zone's units is arranged according to the allowable operating time and comprehensive load curve of each zone's units, and the start-up deficit and start-up redundancy of each zone are determined based on the start-up schedule.

[0014] Based on the aforementioned insufficient start-up capacity and redundant start-up capacity, and following the principle of minimizing tie-line losses, dynamic zoning technology is adopted to support start-up, so as to achieve power balance in each zone and determine the start-up information of the units in each zone at each moment.

[0015] Preferably, the method further includes:

[0016] Based on the unit start-up information of each zone at each moment, the redundancy of the generator start-up power of each zone that is greater than the minimum load of the zone is determined as the peak shaving insufficiency. According to the preset cross-zone mutual assistance ratio, the peak shaving mutual assistance of the whole system is carried out. The part of the whole system unit output that is still greater than the load after the minimum generator output is reduced to the minimum is regarded as the unbalanced power that cannot be peaked. The zones are divided according to the contribution of each zone, and hydropower or wind and solar power are abandoned according to the set priority to generate abandoned electricity.

[0017] Preferably, the step of performing DC power flow calculation based on the integrated load curve and start-up information to determine the AC tie-line power of each tie-line at each time step includes:

[0018]

[0019] Among them, P (k) For the active power of tie line k, P n Let θ be the injected power at node n. n Let b be the angle of effort at node n; ij Let Z be the mutual admittance of nodes ij. ijis an element of the inverse matrix of the stoichiometric array.

[0020] Preferably, the step of adjusting the output of the zoned generator units based on the startup information corresponding to the moment when the AC tie line power exceeds the limit for any target tie line, with the optimization objective of minimizing the sum of squares of the generator power adjustment amount, so that there is no moment when the AC tie line power exceeds the limit for any target tie line, includes:

[0021] The problem of tie line power exceeding the limit adjustment is treated as the following optimization problem:

[0022] The objective function is:

[0023] The total amount constraint is adjusted as follows:

[0024] The constraint on the change in cross-sectional power is:

[0025] The upper and lower limits of the generator output change are constrained as follows: ΔP imin ≤ΔP i ≤ΔP imax For i = 1, 2, ..., N, the Lagrange relaxation method is used to solve this quadratic optimization problem, yielding the following result:

[0026]

[0027] The regulation amount ΔP of each generator is obtained by solving the problem. i ;

[0028] Where N is the number of generators; M is the number of AC cross sections; ΔP i Let ΔP be the change in output of the i-th unit, and its range is ΔP. imin ≤ΔP i ≤ΔP imax ;ΔΦ k This is the correction amount for the power of the k-th AC section; a ki ΔP is the coefficient relating the power at the k-th cross-section to the change in output of the i-th generator; imin ΔP is the minimum output limit of the i-th unit; imax This is the maximum output limit of the i-th unit;

[0029] When the obtained generator regulation does not meet the upper and lower limit constraints, the generator output is forced to the boundary value, the optimization problem is reduced in order, the corresponding matrix is ​​re-formed and the generator regulation is calculated. This process is repeated iteratively until all generator regulation values ​​are obtained. The left-hand vector is corrected accordingly each time the order is reduced.

[0030] According to another aspect of the present invention, a power over-limit handling system for multi-region timing production simulation tie lines is provided, the system comprising:

[0031] The data acquisition unit is used to acquire the comprehensive load curve of each zone and the start-up information of the units in each zone at each moment;

[0032] The AC tie-line power determination unit is used to perform DC power flow calculations based on the comprehensive load curve and start-up information to determine the AC tie-line power of each tie-line at each moment.

[0033] The over-limit tie line and time determination unit is used to compare the AC tie line power of any tie line at each time with the tie line power threshold corresponding to the tie line, and determine the time when the AC tie line power of any tie line exceeds the limit.

[0034] The over-limit adjustment unit is used to adjust the output of the zoned generator units based on the start-up information corresponding to the time when the AC tie line power exceeds the limit for any target tie line, with the optimization objective of minimizing the sum of the squares of the generator power adjustment amount, so that there is no time when the AC tie line power exceeds the limit for any target tie line.

[0035] Preferably, the system further includes: a data acquisition unit, used for:

[0036] Obtain the maintenance schedule for each zone's generating units, and determine the permissible operating time for each zone's generating units based on the maintenance schedule for each zone's generating units;

[0037] The load curves, load reserve rates, emergency reserve capacity, and DC power transmission of each zone are obtained and superimposed onto the load curves according to the reliability of the new energy output forecast to obtain the comprehensive load curves of each zone.

[0038] The start-up schedule for each zone's units is arranged according to the allowable operating time and comprehensive load curve of each zone's units, and the start-up deficit and start-up redundancy of each zone are determined based on the start-up schedule.

[0039] Based on the aforementioned insufficient start-up capacity and redundant start-up capacity, and following the principle of minimizing tie-line losses, dynamic zoning technology is adopted to support start-up, so as to achieve power balance in each zone and determine the start-up information of the units in each zone at each moment.

[0040] Preferably, the system further includes:

[0041] Based on the unit start-up information of each zone at each moment, the redundancy of the generator start-up power of each zone that is greater than the minimum load of the zone is determined as the peak shaving insufficiency. According to the preset cross-zone mutual assistance ratio, the peak shaving mutual assistance of the whole system is carried out. The part of the whole system unit output that is still greater than the load after the minimum generator output is reduced to the minimum is regarded as the unbalanced power that cannot be peaked. The zones are divided according to the contribution of each zone, and hydropower or wind and solar power are abandoned according to the set priority to generate abandoned electricity.

[0042] Preferably, the AC tie-line power determination unit performs DC power flow calculations based on the integrated load curve and start-up information to determine the AC tie-line power of each tie-line at each time moment, including:

[0043]

[0044] Among them, P (k) For the active power of tie line k, P n Let θ be the injected power at node n. n Let b be the angle of effort at node n; ij Let Z be the mutual admittance of nodes ij. ij is an element of the inverse matrix of the stoichiometric array.

[0045] Preferably, the over-limit adjustment unit, based on the start-up information corresponding to the moment when the AC tie line power exceeds the limit for any target tie line, adjusts the output of the zoned units with the minimum sum of squares of the generator power adjustment amount as the optimization objective, so that there is no moment when the AC tie line power exceeds the limit for any target tie line, including:

[0046] The problem of tie line power exceeding the limit adjustment is treated as the following optimization problem:

[0047] The objective function is:

[0048] The total amount constraint is adjusted as follows:

[0049] The constraint on the change in cross-sectional power is:

[0050] The upper and lower limits of the generator output change are constrained as follows: ΔP imin ≤ΔP i ≤ΔP imax i = 1, 2, ..., N

[0051] Solving this quadratic optimization problem using the Lagrange relaxation method yields the following result:

[0052]

[0053] The regulation amount ΔP of each generator is obtained by solving the problem.i ;

[0054] Where N is the number of generators; M is the number of AC cross sections; ΔP i Let ΔP be the change in output of the i-th unit, and its range is ΔP. imin ≤ΔP i ≤ΔP imax ;ΔΦ k This is the correction amount for the power of the k-th AC section; a ki ΔP is the coefficient relating the power at the k-th cross-section to the change in output of the i-th generator; imin ΔP is the minimum output limit of the i-th unit; imax This is the maximum output limit of the i-th unit;

[0055] When the obtained generator regulation does not meet the upper and lower limit constraints, the generator output is forced to the boundary value, the optimization problem is reduced in order, the corresponding matrix is ​​re-formed and the generator regulation is calculated. This process is repeated iteratively until all generator regulation values ​​are obtained. The left-hand vector is corrected accordingly each time the order is reduced.

[0056] This invention provides a method and system for handling power over-limit issues in multi-region time-series production simulation tie lines. The problem of adjusting tie line power over-limit is treated as a quadratic optimization problem. The Lagrange relaxation method is used to solve this quadratic optimization problem. When the tie line exceeds the limit, the adjustment amount of each generator can be quickly and directly obtained. The optimization objective of the output adjustment is to quickly adjust the output of the tie line over-limit zone units with the minimum sum of squares of the adjustment amount. Attached Figure Description

[0057] Exemplary embodiments of the present invention can be more fully understood by referring to the following figures:

[0058] Figure 1 A flowchart of a power over-limit handling method 100 for multi-region timing production simulation tie lines according to an embodiment of the present invention;

[0059] Figure 2 This is a schematic diagram of the topology of a regional power grid according to an embodiment of the present invention;

[0060] Figure 3 A comparison chart showing whether the Haixi-Qinghai connecting line handles over-limit power according to an embodiment of the present invention;

[0061] Figure 4 This is a partial schematic diagram comparing whether the Haixi-Qinghai connecting line handles over-limit line power according to an embodiment of the present invention.

[0062] Figure 5This is a schematic diagram of the power over-limit handling system 500 for a multi-region timing production simulation tie line according to an embodiment of the present invention. Detailed Implementation

[0063] Exemplary embodiments of the invention will now be described with reference to the accompanying drawings. However, the invention may be embodied in many different forms and is not limited to the embodiments described herein. These embodiments are provided to fully and completely disclose the invention and to fully convey its scope to those skilled in the art. The terminology used in the exemplary embodiments illustrated in the drawings is not intended to limit the invention. In the drawings, the same units / elements are referred to by the same reference numerals.

[0064] Unless otherwise stated, the terms used herein (including technical terms) have their common meaning as understood by one of ordinary skill in the art. Furthermore, it is understood that terms defined in commonly used dictionaries should be understood to have a meaning consistent with the context of their relevant field, and not to be interpreted as having an idealized or overly formal meaning.

[0065] Figure 1 This is a flowchart of a power over-limit handling method 100 for multi-region timing production simulation tie lines according to an embodiment of the present invention. Figure 1 As shown, the multi-region time-series production simulation tie-line power over-limit handling method provided by this invention treats the tie-line power over-limit adjustment problem as a quadratic optimization problem. The Lagrange relaxation method is used to solve this quadratic optimization problem, enabling rapid and direct calculation of the adjustment quantities of each generator when the tie-line exceeds the limit. This achieves the optimization objective of minimizing the sum of squares of the adjustment quantities, allowing for rapid output adjustment of the units in the tie-line over-limit zone. The multi-region time-series production simulation tie-line power over-limit handling method 100 provided by this invention begins at step 101, where the comprehensive load curve of each zone and the start-up information of the units in each zone at each time step are obtained.

[0066] Preferably, the method further includes:

[0067] Obtain the maintenance schedule for each zone's generating units, and determine the permissible operating time for each zone's generating units based on the maintenance schedule for each zone's generating units;

[0068] The load curves, load reserve rates, emergency reserve capacity, and DC power transmission of each zone are obtained and superimposed onto the load curves according to the reliability of the new energy output forecast to obtain the comprehensive load curves of each zone.

[0069] The start-up schedule for each zone's units is arranged according to the allowable operating time and comprehensive load curve of each zone's units, and the start-up deficit and start-up redundancy of each zone are determined based on the start-up schedule.

[0070] Based on the aforementioned insufficient start-up capacity and redundant start-up capacity, and following the principle of minimizing tie-line losses, dynamic zoning technology is adopted to support start-up, so as to achieve power balance in each zone and determine the start-up information of the units in each zone at each moment.

[0071] Preferably, the method further includes:

[0072] Based on the unit start-up information of each zone at each moment, the redundancy of the generator start-up power of each zone that is greater than the minimum load of the zone is determined as the peak shaving insufficiency. According to the preset cross-zone mutual assistance ratio, the peak shaving mutual assistance of the whole system is carried out. The part of the whole system unit output that is still greater than the load after the minimum generator output is reduced to the minimum is regarded as the unbalanced power that cannot be peaked. The zones are divided according to the contribution of each zone, and hydropower or wind and solar power are abandoned according to the set priority to generate abandoned electricity.

[0073] When time-series production simulation methods use years as the calculation time scale, the time span is large, the model is complex, there are many variables and many spatial dimensions. When tie line blockage occurs, it is necessary to adjust the output of generators in each zone hourly to eliminate the blockage. An algorithm that balances efficiency and accuracy is needed to handle tie line power exceeding the limit.

[0074] In this invention, when determining whether power exceeds limits based on time-series production simulation, it is necessary to first obtain the comprehensive load curves of each zone and the unit start-up information of each zone at each moment. Specifically, this includes:

[0075] (1) Obtain the maintenance schedule of each zone unit in order to determine the unit's operating time based on the maintenance time;

[0076] (2) Based on the load curves, load reserve rate, emergency reserve capacity and DC power transmission of each zone, the new energy output prediction reliability is superimposed on the load curve to form the comprehensive load curve of each zone.

[0077] (3) Based on the maintenance plan, the start-up arrangements for nuclear power, hydropower, pumped storage, energy storage, thermal power, and gas power are made according to the comprehensive load curve of each zone, so as to determine the insufficient start-up capacity and the redundant start-up capacity of each zone; among them, the insufficient start-up capacity is the thermal power start-up capacity that needs to be supported across zones, and the redundant start-up capacity is the ability to provide cross-zone support.

[0078] (4) Coordinate the start-up of the entire thermal power standby system based on the insufficient start-up amount and the redundant start-up amount. In accordance with the principle of supporting the nearest unit (optimized according to the minimum loss of tie line), the start-up support is carried out by the dynamic zoning technology of the units. Through the start-up arrangements of (3) and (4), the power balance of each zone is ensured as much as possible, thereby determining the start-up information of the units in each zone at each moment.

[0079] In addition, the present invention can also determine the redundancy of the generator starting power of each zone being greater than the minimum load of the zone based on the start-up information of the units in each zone at each moment as the peak shaving insufficiency. According to the preset cross-zone mutual assistance ratio, the peak shaving mutual assistance of the whole system is carried out. The part of the whole system unit output that is still greater than the load when the generator output is reduced to the minimum is regarded as the unbalanced power that cannot be peaked. The system is divided into zones according to the contribution of each zone, and water or wind and solar power is abandoned according to the set priority order to generate abandoned electricity.

[0080] In step 102, DC power flow calculation is performed based on the comprehensive load curve and start-up information to determine the AC tie-line power of each tie line at each moment.

[0081] Preferably, the step of performing DC power flow calculation based on the integrated load curve and start-up information to determine the AC tie-line power of each tie-line at each time step includes:

[0082]

[0083] Among them, P (k) For the active power of tie line k, P n Let θ be the injected power at node n. n Let b be the angle of effort at node n; ij Let Z be the mutual admittance of nodes ij. ij is an element of the inverse matrix of the stoichiometric array.

[0084] In step 103, for any tie line, the AC tie line power of the tie line at each time is compared with the tie line power threshold corresponding to the tie line to determine the time when the AC tie line power of the tie line exceeds the limit.

[0085] In this invention, each tie line corresponds to a tie line power threshold, and the tie line power thresholds for different tie lines can be different. For any tie line, the AC tie line power of that tie line at each moment is compared with the tie line power threshold corresponding to that tie line. When the tie line power of any tie line at a certain moment is greater than the corresponding tie line power threshold, it is determined that the tie line has exceeded the power limit at that moment, thereby determining the moment when the AC tie line power exceeds the limit for that tie line.

[0086] In step 104, for any target tie line where the AC tie line power exceeds the limit, based on the start-up information corresponding to the time when the AC tie line power exceeds the limit for any target tie line, the output of the zoned units is adjusted with the goal of minimizing the sum of squares of the generator power adjustment amount, so that there is no time when the AC tie line power exceeds the limit for any target tie line.

[0087] Preferably, the step of adjusting the output of the zoned generator units based on the startup information corresponding to the moment when the AC tie line power exceeds the limit for any target tie line, with the optimization objective of minimizing the sum of squares of the generator power adjustment amount, so that there is no moment when the AC tie line power exceeds the limit for any target tie line, includes:

[0088] The problem of tie line power exceeding the limit adjustment is treated as the following optimization problem:

[0089] The objective function is:

[0090] The total amount constraint is adjusted as follows:

[0091] The constraint on the change in cross-sectional power is:

[0092] The upper and lower limits of the generator output change are constrained as follows: ΔP imin ≤ΔP i ≤ΔP imax i = 1, 2, ..., N

[0093] Solving this quadratic optimization problem using the Lagrange relaxation method yields the following result:

[0094]

[0095] The regulation amount ΔP of each generator is obtained by solving the problem. i ;

[0096] Where N is the number of generators; M is the number of AC cross sections; ΔP i Let ΔP be the change in output of the i-th unit, and its range is ΔP. imin ≤ΔP i ≤ΔP imax ;ΔΦ k This is the correction amount for the power of the k-th AC section; a ki ΔP is the coefficient relating the power at the k-th cross-section to the change in output of the i-th generator; imin ΔP is the minimum output limit of the i-th unit; imax This is the maximum output limit of the i-th unit;

[0097] When the obtained generator regulation does not meet the upper and lower limit constraints, the generator output is forced to the boundary value, the optimization problem is reduced in order, the corresponding matrix is ​​re-formed and the generator regulation is calculated. This process is repeated iteratively until all generator regulation values ​​are obtained. The left-hand vector is corrected accordingly each time the order is reduced.

[0098] In this invention, DC power flow calculations are performed based on load curves and operating rates to determine the AC power of each tie line at each moment.

[0099] The formula for calculating DC power flow is as follows:

[0100]

[0101] Among them, P i Inject power into node i, b ij Let θ be the mutual admittance of nodes ij. i The nodal power angle.

[0102] Since the susceptance matrix is ​​a singular matrix, a balancing machine must be set up. Let node s be the balancing machine.

[0103]

[0104] The injected power of all nodes except node s is known. Without considering line power losses, the total injected power to all nodes is 0.

[0105] When performing triangular decomposition, simply skip node s. Perform triangular decomposition on the s-column, s-row matrix, to obtain its inverse matrix, i.e.:

[0106]

[0107] Among them, P n Let θ be the injected power at node n. n p is the angle of effort at node n; s The injected power is the power for the balancing machine node s.

[0108] In this invention, when it is determined that a tie line exceeds its limit, if the nodes on both sides of the AC tie line are i and j, the active power of the line is:

[0109]

[0110] Where n is the number of generators in the two zones corresponding to the tie line.

[0111] When an AC section contains multiple AC lines, the power of the AC section is the sum of the power of each line. Assuming section Φ1 contains line K1, then:

[0112]

[0113]

[0114]

[0115] At this point, the problem of excessive tie line power adjustment can be treated as the following optimization problem:

[0116] Objective function:

[0117] Adjusting total constraints:

[0118] Cross-sectional power change constraint:

[0119] Upper and lower limits of generator output change constraints: ΔP imin ≤ΔP i ≤ΔP imax i = 1, 2, ..., N

[0120] Where: N is the number of generators; M is the number of AC cross sections; ΔP i Let ΔP be the change in output of the i-th unit, and its range is ΔP. imin ≤ΔP i ≤ΔP imax ;ΔΦ k is the correction amount for the power of the k-th AC section; is the relationship coefficient between the power of the k-th section and the change in the output of the i-th generator.

[0121] The Lagrange relaxation method is used to solve this quadratic optimization problem, introducing Lagrange coefficients λ and gk (k = 1, 2, ..., M). The objective function is reduced to:

[0122]

[0123] Applying the extreme value condition, the following relationship is obtained:

[0124]

[0125]

[0126]

[0127] Further analysis revealed:

[0128]

[0129] Then, the regulation value ΔP of each generator can be obtained by directly solving the problem. i And various Lagrange multipliers.

[0130] When the obtained generator regulation does not meet the upper and lower limit constraints, the generator output is forced to the boundary value, the optimization problem is reduced in order, the corresponding matrix is ​​reconstructed, and the generator regulation is calculated. This process is iterated repeatedly until all generator regulation values ​​are obtained. It is important to note that the left-hand vector is corrected accordingly with each order reduction.

[0131] In addition, for convenience in practical use, only the left-hand vector can be modified while keeping the matrix unchanged, and the corresponding rows and columns can be skipped when performing matrix decomposition.

[0132] To ensure stability while maintaining computational speed, the generator output adjustment limit can generally be ignored. The matrix is ​​solved only once, and the output adjustment obtained is used as the overall output adjustment for each zone. The curtailment of wind, solar, and hydropower is determined based on the overall situation.

[0133] Taking a regional power grid as an example, the power grid structure is as follows: Figure 2 As shown, the power limit of the interconnection line between the Haixi power grid and the Qinghai main grid is 3350MW. Production simulation calculations are performed according to steps 101-102, resulting in the following... Figure 3 and Figure 4 When the power of the tie line is shown, it is found that the Haixi-Qinghai main grid tie line exceeds the limit for 324 hours out of 8760 hours. Then, the method proposed in this invention 104 is used to handle the tie line over-limit, so that the power of all 324-hour tie lines is limited to below 3350MW, thereby determining the unit start-up plan for the whole year.

[0134] The method of this invention treats the tie line power over-limit adjustment problem as a quadratic optimization problem and uses the Lagrange relaxation method to solve this quadratic optimization problem. It can quickly and directly solve for the adjustment of each generator when the tie line exceeds the limit, so as to achieve the optimization objective of the output adjustment, which is to minimize the sum of the squares of the adjustment amounts and quickly adjust the output of the tie line over-limit zone units.

[0135] Figure 5 This is a schematic diagram of a power over-limit handling system 500 for a multi-region timing production simulation tie line according to an embodiment of the present invention. Figure 5 As shown, the power over-limit processing system 500 for multi-region timing production simulation tie lines provided in this embodiment of the invention includes: a data acquisition unit 501, an AC tie line power determination unit 502, an over-limit tie line and time determination unit 503, and an over-limit adjustment unit 504.

[0136] Preferably, the data acquisition unit 501 is used to acquire the comprehensive load curve of each zone and the start-up information of the units in each zone at each moment.

[0137] Preferably, the system further includes: a data acquisition unit, used for:

[0138] Obtain the maintenance schedule for each zone's generating units, and determine the permissible operating time for each zone's generating units based on the maintenance schedule for each zone's generating units;

[0139] The load curves, load reserve rates, emergency reserve capacity, and DC power transmission of each zone are obtained and superimposed onto the load curves according to the reliability of the new energy output forecast to obtain the comprehensive load curves of each zone.

[0140] The start-up schedule for each zone's units is arranged according to the allowable operating time and comprehensive load curve of each zone's units, and the start-up deficit and start-up redundancy of each zone are determined based on the start-up schedule.

[0141] Based on the aforementioned insufficient start-up capacity and redundant start-up capacity, and following the principle of minimizing tie-line losses, dynamic zoning technology is adopted to support start-up, so as to achieve power balance in each zone and determine the start-up information of the units in each zone at each moment.

[0142] Preferably, the system further includes:

[0143] Based on the unit start-up information of each zone at each moment, the redundancy of the generator start-up power of each zone that is greater than the minimum load of the zone is determined as the peak shaving insufficiency. According to the preset cross-zone mutual assistance ratio, the peak shaving mutual assistance of the whole system is carried out. The part of the whole system unit output that is still greater than the load after the minimum generator output is reduced to the minimum is regarded as the unbalanced power that cannot be peaked. The zones are divided according to the contribution of each zone, and hydropower or wind and solar power are abandoned according to the set priority to generate abandoned electricity.

[0144] Preferably, the AC tie-line power determination unit 502 is used to perform DC power flow calculation based on the comprehensive load curve and start-up information to determine the AC tie-line power of each tie-line at each time.

[0145] Preferably, the AC tie-line power determination unit 502 performs DC power flow calculations based on the comprehensive load curve and start-up information to determine the AC tie-line power of each tie-line at each moment, including:

[0146]

[0147] Among them, P (k) For the active power of tie line k, P n Let θ be the injected power at node n. n Let b be the angle of effort at node n; ij Let Z be the mutual admittance of nodes ij. ij is an element of the inverse matrix of the stoichiometric array.

[0148] Preferably, the over-limit tie line and time determination unit 503 is used to compare the AC tie line power of any tie line at each time with the tie line power threshold corresponding to the tie line, and determine the time when the AC tie line power of the corresponding tie line exceeds the limit.

[0149] Preferably, the over-limit adjustment unit 504 is used to adjust the output of the zoned generator units for any target tie line where there is an AC tie line power over-limit, based on the start-up information corresponding to the time when the AC tie line power over-limit occurs, with the goal of minimizing the sum of the squares of the generator power adjustment amount, so that there is no time when the AC tie line power over-limit occurs for any target tie line.

[0150] Preferably, the over-limit adjustment unit 504, based on the start-up information corresponding to the moment when the AC tie line power exceeds the limit for any target tie line, adjusts the output of the zoned units with the minimum sum of squares of the generator power adjustment amount as the optimization objective, so that there is no moment when the AC tie line power exceeds the limit for any target tie line, including:

[0151] The problem of tie line power exceeding the limit adjustment is treated as the following optimization problem:

[0152] The objective function is:

[0153] The total amount constraint is adjusted as follows:

[0154] The constraint on the change in cross-sectional power is:

[0155] The upper and lower limits of the generator output change are constrained as follows: ΔP imin ≤ΔP i ≤ΔP imax For i = 1, 2, ..., N, the Lagrange relaxation method is used to solve this quadratic optimization problem, yielding the following result:

[0156]

[0157] The regulation amount ΔP of each generator is obtained by solving the problem. i ;

[0158] Where N is the number of generators; M is the number of AC cross sections; ΔP i Let ΔP be the change in output of the i-th unit, and its range is ΔP. imin ≤ΔP i ≤ΔP imax ;ΔΦ k This is the correction amount for the power of the k-th AC section; a ki ΔP is the coefficient relating the power at the k-th cross-section to the change in output of the i-th generator; imin ΔP is the minimum output limit of the i-th unit; imax This is the maximum output limit of the i-th unit;

[0159] When the obtained generator regulation does not meet the upper and lower limit constraints, the generator output is forced to the boundary value, the optimization problem is reduced in order, the corresponding matrix is ​​re-formed and the generator regulation is calculated. This process is repeated iteratively until all generator regulation values ​​are obtained. The left-hand vector is corrected accordingly each time the order is reduced.

[0160] The power over-limit processing system 500 for multi-region timing production simulation tie lines in an embodiment of the present invention corresponds to the power over-limit processing method 100 for multi-region timing production simulation tie lines in another embodiment of the present invention, and will not be described again here.

[0161] The invention has been described with reference to a few embodiments. However, as will be known to those skilled in the art, and as defined in the appended claims, other embodiments besides those disclosed above fall equivalently within the scope of the invention.

[0162] Generally, all terms used in the claims are to be interpreted according to their ordinary meaning in the art, unless otherwise expressly defined herein. All references to “a / the / the [device, component, etc.]” ​​are openly interpreted as at least one instance of said device, component, etc., unless otherwise expressly stated. The steps of any method disclosed herein need not be performed in the exact order disclosed unless explicitly stated otherwise.

[0163] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product embodied on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0164] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0165] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0166] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0167] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the specific implementation of the present invention. Any modifications or equivalent substitutions that do not depart from the spirit and scope of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. A method for handling power limit violations in multi-region time-series production simulation interconnects, characterized in that, The method includes: Obtain the comprehensive load curve of each zone and the unit start-up information of each zone at each time. Based on the comprehensive load curve and start-up information, DC power flow calculation is performed to determine the AC tie-line power of each tie line at each moment; For any tie line, compare the AC tie line power of that tie line at each time with the tie line power threshold corresponding to that tie line to determine the time when the AC tie line power of that tie line exceeds the limit. For any target tie line where the AC tie line power exceeds the limit, based on the start-up information corresponding to the time when the AC tie line power exceeds the limit for any target tie line, the output of the zoned units is adjusted with the goal of minimizing the sum of squares of the generator power adjustment amount, so that there is no time when the AC tie line power exceeds the limit for any target tie line. Specifically, based on the start-up information corresponding to the moment when the AC tie line power exceeds the limit for any target tie line, and with the goal of minimizing the sum of squares of the generator power adjustment, the output of the zoned units is adjusted to ensure that there are no moments when the AC tie line power exceeds the limit for any target tie line, including: The problem of tie line power exceeding the limit adjustment is treated as the following optimization problem: The objective function is: , The total amount constraint is adjusted as follows: , The constraint on the change in cross-sectional power is: The upper and lower limits of the generator output change are constrained as follows: , Solving this optimization problem using the Lagrange relaxation method yields the following result: The regulation values ​​of each generator are obtained by solving the problem. ; Where N is the number of generators; M is the number of AC cross sections; Let be the change in output of the i-th unit, and its range is: ; This is the correction amount for the power of the k-th AC section; The coefficient representing the relationship between the power of the k-th cross-section and the change in the output of the i-th generator is denoted as . This is the minimum output limit for the i-th unit; This is the maximum output limit of the i-th unit; When the obtained generator regulation does not meet the upper and lower limit constraints, the generator output is forced to the boundary value, the optimization problem is reduced in order, the corresponding matrix is ​​re-formed and the generator regulation is calculated. This process is repeated iteratively until all generator regulation values ​​are obtained. The left-hand vector is corrected accordingly each time the order is reduced.

2. The method according to claim 1, characterized in that, The method further includes: Obtain the maintenance schedule for each zone's generating units, and determine the permissible operating time for each zone's generating units based on the maintenance schedule for each zone's generating units; The load curves, load reserve rates, emergency reserve capacity, and DC power transmission of each zone are obtained and superimposed onto the load curves according to the reliability of the new energy output forecast to obtain the comprehensive load curves of each zone. The start-up schedule for each zone's units is arranged according to the allowable operating time and comprehensive load curve of each zone's units, and the start-up deficit and start-up redundancy of each zone are determined based on the start-up schedule. Based on the aforementioned insufficient start-up capacity and redundant start-up capacity, and following the principle of minimizing tie-line losses, dynamic zoning technology is adopted to support start-up, so as to achieve power balance in each zone and determine the start-up information of the units in each zone at each moment.

3. The method according to claim 2, characterized in that, The method further includes: Based on the unit start-up information of each zone at each moment, the redundancy of the generator start-up power of each zone that is greater than the minimum load of the zone is determined as the peak-shaving deficiency. According to the preset cross-zone mutual assistance ratio, the peak-shaving mutual assistance of the whole system is carried out. The part of the whole system unit output that is still greater than the load after the minimum generator output is reduced to the minimum is regarded as the unbalanced power. The zones are divided according to the contribution of each zone, and hydropower or wind and solar power are abandoned according to the set priority to generate abandoned electricity.

4. The method according to claim 1, characterized in that, The step of calculating DC power flow based on the comprehensive load curve and start-up information to determine the AC tie-line power of each tie-line at each moment includes: ， in, For the active power of tie line k, Let n be the injected power. Let n be the angle of attack at node n; Let the mutual admittances of nodes ij be . is an element of the inverse matrix of the stoichiometric array.

5. A power limit overrun handling system for multi-region time-series production simulation interconnects, characterized in that, The system includes: The data acquisition unit is used to acquire the comprehensive load curve of each zone and the start-up information of the units in each zone at each moment; The AC tie-line power determination unit is used to perform DC power flow calculations based on the comprehensive load curve and start-up information to determine the AC tie-line power of each tie-line at each moment. The over-limit tie line and time determination unit is used to compare the AC tie line power of any tie line at each time with the tie line power threshold corresponding to the tie line, and determine the time when the AC tie line power of any tie line exceeds the limit. The over-limit adjustment unit is used to adjust the output of the zoned generator units based on the start-up information corresponding to the time when the AC tie line power exceeds the limit for any target tie line with over-limit AC tie line power, with the optimization objective of minimizing the sum of squares of the generator power adjustment amount, so that there is no time when the AC tie line power exceeds the limit for any target tie line. The over-limit adjustment unit, based on the start-up information corresponding to the moment when the AC tie line power exceeds the limit for any target tie line, adjusts the output of the zoned units with the goal of minimizing the sum of squares of the generator power adjustment amount, so that there is no moment when the AC tie line power exceeds the limit for any target tie line, including: The problem of tie line power exceeding the limit adjustment is treated as the following optimization problem: The objective function is: , The total amount constraint is adjusted as follows: , The constraint on the change in cross-sectional power is: The upper and lower limits of the generator output change are constrained as follows: , Solving this optimization problem using the Lagrange relaxation method yields the following result: The regulation values ​​of each generator are obtained by solving the problem. ; Where N is the number of generators; M is the number of AC cross sections; Let be the change in output of the i-th unit, and its range is: ; This is the correction amount for the power of the k-th AC section; The coefficient representing the relationship between the power of the k-th cross-section and the change in the output of the i-th generator is given by the coefficient. This is the minimum output limit for the i-th unit; This is the maximum output limit of the i-th unit; When the obtained generator regulation does not meet the upper and lower limit constraints, the generator output is forced to the boundary value, the optimization problem is reduced in order, the corresponding matrix is ​​re-formed and the generator regulation is calculated. This process is repeated iteratively until all generator regulation values ​​are obtained. The left-hand vector is corrected accordingly each time the order is reduced.

6. The system according to claim 5, characterized in that, The system further includes: a data acquisition unit, used for: Obtain the maintenance schedule for each zone's generating units, and determine the permissible operating time for each zone's generating units based on the maintenance schedule for each zone's generating units; The load curves, load reserve rates, emergency reserve capacity, and DC power transmission of each zone are obtained and superimposed onto the load curves according to the reliability of the new energy output forecast to obtain the comprehensive load curves of each zone. The start-up schedule for each zone's units is arranged according to the allowable operating time and comprehensive load curve of each zone's units, and the start-up deficit and start-up redundancy of each zone are determined based on the start-up schedule. Based on the aforementioned insufficient start-up capacity and redundant start-up capacity, and following the principle of minimizing tie-line losses, dynamic zoning technology is adopted to support start-up, so as to achieve power balance in each zone and determine the start-up information of the units in each zone at each moment.

7. The system according to claim 6, characterized in that, The system also includes: Based on the unit start-up information of each zone at each moment, the redundancy of the generator start-up power of each zone that is greater than the minimum load of the zone is determined as the peak-shaving deficiency. According to the preset cross-zone mutual assistance ratio, the peak-shaving mutual assistance of the whole system is carried out. The part of the whole system unit output that is still greater than the load after the minimum generator output is reduced to the minimum is regarded as the unbalanced power. The zones are divided according to the contribution of each zone, and hydropower or wind and solar power are abandoned according to the set priority to generate abandoned electricity.

8. The system according to claim 5, characterized in that, The AC tie-line power determination unit performs DC power flow calculations based on the comprehensive load curve and start-up information to determine the AC tie-line power of each tie-line at each moment, including: ， in, For the active power of tie line k, Let n be the injected power. Let n be the angle of attack at node n; Let the mutual admittances of nodes ij be . is an element of the inverse matrix of the stoichiometric array.

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