A wind power and energy storage collaborative replacement of traditional unit capacity planning method based on multi-index ranking

Abstract

The present application relates to a kind of wind power and energy storage collaborative replacement traditional unit capacity planning method based on multi-index sequencing, comprising: obtaining candidate traditional unit and candidate wind storage access area, and constructing candidate replacement scheme;Characteristic value change sensitivity is calculated using the state matrix disturbance caused by candidate replacement scheme, and replacement modal damping sensitivity is calculated according to characteristic value change sensitivity, the comprehensive replacement sequencing score of candidate replacement scheme is generated, and the candidate replacement scheme with the highest comprehensive replacement sequencing score is selected as the preferred replacement scheme of the current round;Based on benchmark operation model, power flow calculation and small signal stability analysis are carried out on the replacement capacity in the preferred replacement scheme, and the benchmark operation result is obtained, which is compared with the preset target constraint, and the capacity planning result of the maximum acceptable replacement scheme is obtained.The present application realizes the collaborative determination of traditional unit replacement order, wind storage access area and replacement capacity.

Description

Technical Field

[0001] This invention relates to the field of new energy power system planning technology, and in particular to a method for planning the capacity of wind power and energy storage to synergistically replace traditional generating units based on multi-index ranking. Background Technology

[0002] As the installed capacity of new energy sources such as wind power continues to increase, the operating mode of traditional synchronous generator units in the power system is gradually changing. Some traditional units are facing the need for reduced output operation, standby operation, or even decommissioning. Traditional units not only provide active power output but also provide dynamic support capabilities such as inertia support, damping support, voltage support, and short-circuit capacity to the system. Therefore, when using wind power and energy storage to replace traditional units, it is not enough to simply rely on the installed capacity or active power balance relationship for equivalent capacity replacement. It is also necessary to consider the impact of the decommissioning of traditional units on the system power flow distribution, voltage level, and small-signal stability.

[0003] Existing methods for renewable energy substitution or capacity planning often focus on renewable energy absorption capacity, economic efficiency, or static power flow constraints, typically lacking quantitative prioritization criteria for which traditional generating units should be replaced and which regions wind power and energy storage should be integrated into. While some methods consider system stability, they often only verify stability indicators before and after substitution, making it difficult to directly determine whether the removal of a particular traditional generating unit and integration with wind and energy storage will improve or worsen the electromechanical oscillation mode damping during the substitution plan formulation stage. Furthermore, existing methods usually determine the substitution order all at once, failing to update the order based on changes in system operating points and dynamic characteristics after each round of substitution, easily leading to mismatches between subsequent substitution plans and the actual system state.

[0004] Therefore, there is an urgent need to propose a capacity planning method that can simultaneously consider the value of traditional unit capacity release, the margin of wind and energy storage network access, and the impact of electromechanical oscillation damping, so as to achieve the coordinated determination of the replacement sequence of traditional units, the wind and energy storage access area, and the replacement capacity. Summary of the Invention

[0005] To address the problems existing in the prior art, the present invention aims to provide a capacity planning method for the coordinated replacement of traditional generating units by wind power and energy storage based on multi-index ranking. This method aims to solve the problems of lack of quantitative basis for the selection of replacement targets for traditional generating units, disconnect between wind and energy storage capacity configuration and dynamic system support requirements, lack of progressive verification in the replacement process, and unclear boundaries of the maximum acceptable replacement capacity.

[0006] To achieve the above objectives, the present invention provides the following solution: A method for coordinating wind power and energy storage to replace traditional generating unit capacity planning based on multi-index ranking includes: Obtain candidate traditional turbine units and candidate wind storage access areas, and construct candidate alternative solutions; The sensitivity of eigenvalue changes is calculated using the state matrix perturbation caused by the candidate alternatives. The sensitivity of alternative mode damping is calculated based on the sensitivity of eigenvalue changes. A comprehensive alternative ranking score is generated for the candidate alternatives. The candidate alternative with the highest comprehensive alternative ranking score is selected as the priority alternative for the current round. Based on the benchmark operation model, power flow calculation and small-signal stability analysis are performed on the alternative capacity of the preferred alternative scheme to obtain the benchmark operation results. The benchmark operation results are compared and analyzed with the preset target constraints to obtain the capacity planning results of the maximum acceptable alternative scheme.

[0007] Optionally, calculating the sensitivity to changes in the eigenvalues ​​includes: Constructing the state matrix perturbation caused by the candidate alternative: ; in, For the first Traditional generator units were phased out and in the 1st The state matrix disturbance caused by the integration of wind power and energy storage in a region. For a small substitution ratio increase, For the first The state matrix of the system after the wheel replacement; The sensitivity to eigenvalue changes is calculated using the perturbation of the state matrix: ; in, For candidate alternatives to the first Sensitivity to changes in the eigenvalues ​​of individual electromechanical oscillation modes and The first The left and right feature vectors corresponding to each modality.

[0008] Optionally, calculating the alternative modal damping sensitivity includes: Small-signal eigenvalue analysis is performed on the planned power system to screen electromechanical oscillation modes, and the damping ratio of the electromechanical oscillation modes is calculated: ; in, For the first After the replacement of the first round The real part of each modal eigenvalue. For the first After the replacement of the first round The imaginary part of each modal eigenvalue. For the first After the replacement of the first round Modal damping ratio; The alternative mode damping sensitivity is calculated based on the sensitivity to the change in the eigenvalue and the damping ratio of the electromechanical oscillation mode: ; in, For candidate alternatives to the first Sensitivity of damping ratio of individual electromechanical oscillation modes; when When, it indicates that the candidate alternative is beneficial to improving the damping of the electromechanical oscillation mode. When this occurs, it indicates that the candidate alternative may reduce the damping of the electromechanical oscillation mode. and These are the real and imaginary parts of the sensitivity to changes in eigenvalues, respectively. and The first The left and right feature vectors corresponding to each modality.

[0009] Optionally, generating the comprehensive alternative ranking score for the candidate alternatives includes: ; ; ; ; in, For the first The comprehensive alternative ranking score of the round of candidate alternatives, The normalized unit replaceable output coefficient, This is the normalized alternative mode damping sensitivity. This is the normalized access power flow margin coefficient. For the corresponding weights, The comprehensive alternative modal damping sensitivity of the candidate alternatives. For the first A pool of candidate conventional generating units, For the first Weights of each electromechanical oscillation mode For the first Wheel of Life The output coefficient of traditional Taiwanese generator units can be replaced. For the first Wheel of Life The current active power output of Taiwan's traditional generating units For the first A pool of candidate conventional generating units, For the first Wheel of Life The current contributions of the traditional aircraft carriers in Taiwan's candidate fleet are noteworthy. For the first Access flow margin coefficient of candidate alternatives in round, The first [unclear] was determined after comprehensively considering node voltage constraints, line power flow constraints, and regional resource access limits. The upper limit of wind power and energy storage capacity allowed for access in each candidate area. For the first The first replacement The wind power and energy storage capacity already connected in each candidate access area For the first Wheel of Life Replacement capacity of traditional units.

[0010] Optionally, the alternative capacity includes: ; ; in, For the first The wind power installed capacity configured in the priority access area, For the first Replacement capacity of traditional generating units; The reliability coefficient of wind power capacity in this region. For the first The energy storage capacity configured in the priority access area, This is the basic configuration factor for energy storage capacity. This is the damping compensation coefficient. The lower limit of the set electromechanical modal damping ratio, This is to replace the predicted value of the post-critical electromechanical mode damping ratio.

[0011] Optionally, obtaining the benchmark results includes: Based on the steady-state power flow sub-model in the benchmark operation model, power flow calculation is performed on the alternative capacity in the preferred alternative scheme to obtain node voltage, line power flow, active power output and reactive power output of traditional units; Based on the small-signal dynamic sub-model in the benchmark operating model, small-signal stability analysis is performed on the alternative capacity in the preferred alternative scheme to obtain system characteristic values, electromechanical oscillation modes, modal damping ratios, and the impact of candidate alternative schemes on system stability.

[0012] Optionally, obtaining the capacity planning result of the maximum acceptable alternative includes: The benchmark operation results are compared and analyzed with preset target constraints. If the benchmark operation results meet the preset target constraints, the current round's replacement scheme is accepted. If the benchmark operation results do not meet the preset target constraints, the replacement ratio of the current candidate replacement scheme is reduced and re-analyzed. If the replacement ratio of the current candidate replacement scheme is reduced to the set minimum replacement ratio and still does not meet the preset target constraints, the current candidate replacement scheme is determined to be unacceptable, and the next candidate replacement scheme in the comprehensive replacement ranking is selected for re-analysis. If all candidate replacement schemes in the current round cannot meet the preset target constraints at the set minimum replacement ratio, the progressive replacement is stopped, and the scheme accepted in the previous round is determined as the maximum acceptable replacement scheme under the current system conditions. The capacity planning result for the coordinated replacement of traditional units by wind power and energy storage is output.

[0013] Optionally, the minimum substitution ratio is the minimum non-zero substitution ratio allowed in the progressive substitution trial calculation, which can be preset according to the substitution ratio search step size and capacity planning accuracy.

[0014] Optionally, the preset target constraint includes: Node voltage constraints: , ; In the formula, For the first After the wheel replacement node The voltage amplitude; and These are the minimum and maximum voltage limits allowed for the node, respectively; For the system node set; Power flow constraints on the line: , ; In the formula, For the first After the replacement of the wheel, the line The meritorious trend; This represents the maximum allowable transmission capacity of the line. For the set of routes; Wind power capacity constraints: ; In the formula, For the first The installed capacity of wind power in the alternative wheel configuration; For the first The maximum wind power capacity allowed to be connected in the candidate wind and energy storage access area; Energy storage capacity constraints include energy storage power constraints and energy storage energy constraints; Energy storage power constraints: ; In the formula, For the first The energy storage capacity configured for the wheel replacement scheme; For the first The maximum energy storage capacity allowed to be connected to the candidate wind and energy storage access areas; Energy storage energy constraints: ; In the formula, For the first The energy storage capacity configured for wheel replacement solutions; For the first The maximum energy storage capacity allowed to be connected to the candidate wind and energy storage access areas; Small-signal stability constraints: ; In the formula, For the first After the replacement of the first round Real part of each modal eigenvalue; Electromechanical modal damping constraints: ; In the formula, For the first After the replacement of the first round Modal damping ratio; This is the lower limit of the set electromechanical modal damping ratio.

[0015] The beneficial effects of this invention are as follows: This invention evaluates the retirement of traditional generating units and the integration of wind power and energy storage as a whole candidate replacement scheme, simultaneously considering the coupling effects of the replaced units and the wind and energy storage integration areas. It quantifies the value of the active power capacity that can be released from traditional generating units through the unit replacement output coefficient, quantifies the network feasibility of candidate areas to accommodate wind power and energy storage through the power flow margin coefficient, and judges the direction of improvement or deterioration of electromechanical oscillation mode damping by the candidate replacement schemes through the replacement mode damping sensitivity, thus forming a ranking basis that takes into account capacity, integration, and stability. Furthermore, after each round of replacement, this invention recalculates the system state matrix, modal characteristics, and ranking results, and combines progressive replacement with a safety verification mechanism to determine the maximum acceptable replacement capacity under the premise of meeting voltage, power flow, capacity, and small-signal stability constraints, providing a reliable planning basis for the orderly retirement of traditional generating units and the large-scale replacement of wind and energy storage. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a flowchart of a wind power and energy storage synergistic replacement method for traditional unit capacity planning based on multi-index ranking, according to an embodiment of the present invention. Figure 2 This is a flowchart of the progressive alternative capacity planning algorithm based on multi-index sorting in an embodiment of the present invention. Detailed Implementation

[0018] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0019] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0020] like Figure 1 As shown, this embodiment discloses a method for planning the capacity of wind power and energy storage to synergistically replace traditional generating units based on multi-index ranking, including: Establish a baseline operating model for the power system to be planned. The baseline operating model includes a steady-state power flow model and a small-signal dynamic model. Identify candidate conventional turbine units and candidate wind-storage access areas, and exclude units that do not meet the requirements; Construct candidate alternatives by combining candidate traditional generating units with candidate wind and energy storage access areas to form candidate alternatives for the retirement of traditional generating units and the access of wind power and energy storage. Small-signal eigenvalue analysis is performed on the planned power system to screen electromechanical oscillation modes and the damping ratio of the electromechanical oscillation modes is calculated. For each candidate alternative, construct the state matrix perturbation caused by the candidate alternative, and calculate the sensitivity of eigenvalue changes based on the state matrix perturbation, the left eigenvector, and the right eigenvector; The sensitivity of the alternative mode damping is calculated based on the sensitivity of the eigenvalue change, which is used to determine the direction of improvement or deterioration of the electromechanical oscillation mode damping by the candidate alternative. The comprehensive alternative ranking score of candidate alternative schemes is calculated based on the unit's alternative output coefficient, alternative mode damping sensitivity, and access power flow margin coefficient. Priority alternatives are determined based on a comprehensive alternative ranking score, and the wind power installed capacity and energy storage capacity are also determined. The priority alternative schemes are subjected to progressive substitution trials and safety checks. If the constraints of node voltage, line power flow, wind power capacity, energy storage capacity, small signal stability, and electromechanical mode damping are met, the alternative scheme in this round is accepted. If not, the substitution ratio of the current candidate alternative scheme is reduced and the trial is recalculated. If the constraints are still not met after the substitution ratio is reduced to the set minimum substitution ratio, the next candidate alternative scheme is selected and the trial is recalculated. After each round of alternative solutions is accepted, the system operating point, small-signal state matrix, electromechanical oscillation mode, alternative mode damping sensitivity, and comprehensive alternative ranking score are recalculated until the alternative stopping boundary is reached, and the capacity planning results are output.

[0021] In one embodiment, this embodiment discloses a method for planning the capacity of wind power and energy storage to synergistically replace traditional generating units based on multi-index ranking, including: S1: Establish a baseline operating model for the power system to be planned; S2: Determine the candidate set of conventional generating units and the candidate wind-storage access area; S3: Construct candidate alternatives; S4: Screen electromechanical oscillation modes and calculate damping ratios; S5: Construct the state matrix perturbation of candidate alternatives; S6: Calculate the sensitivity to changes in eigenvalues; S7: Computer group can replace output coefficient, replace modal damping sensitivity, and access power flow margin coefficient; S8: Calculate the comprehensive alternative ranking score; S9: Determine wind power and energy storage capacity; S10: Perform progressive substitution calculations and safety checks; S11: Recalculate the substitution order after each round of substitution; S12: Determine the alternative stopping boundary and output the capacity planning results; Specifically, in step S1, the basic parameters and operating constraints of the power system to be planned are obtained, and a benchmark operating model including traditional generating units, wind farms, energy storage systems, loads and power grid networks is established.

[0022] Furthermore, conventional generating units include synchronous generator sets, thermal power units, gas turbine units, hydropower units, or other conventional generating units with rotational inertia and voltage support capabilities.

[0023] Furthermore, the benchmark operating model includes a steady-state power flow model and a small-signal dynamic model. The steady-state power flow model is used to calculate node voltages, line power flow, and active and reactive power outputs of conventional generating units; the small-signal dynamic model is used to calculate system eigenvalues, electromechanical oscillation modes, mode damping ratios, and the impact of candidate alternatives on system stability.

[0024] Specifically, near the current operating point, the system is linearized to obtain a baseline small-signal state-space model as the small-signal dynamic model: ; In the formula, For the first The increment of system state variables after wheel replacement; For the first The state matrix of the system after the round substitution; when hour, This is the baseline system state matrix before the replacement of traditional units.

[0025] Specifically, in step S2, traditional generating units in the planned power system are screened to exclude those that are not suitable as replacements, thus obtaining a set of candidate traditional generating units. Furthermore, conventional units that are unsuitable as replacements include at least the following: (1) Units that serve as balancing nodes and are not suitable for withdrawal; (2) External equivalent units or boundary equivalent units; (3) Units that cause power flow non-convergence after being withdrawn; (4) Units that cause critical node voltage to exceed limits after being shut down; (5) Units whose small-signal stability does not meet the constraints after exiting the system; (6) Units that have already been replaced in previous rounds or no longer meet the conditions for continued replacement.

[0026] Meanwhile, candidate wind-storage access areas are determined based on wind resource conditions, energy storage deployment conditions, node voltage levels, line power flow margin, and regional capacity limits. Furthermore, the candidate wind-storage access areas are those that meet the conditions for wind power access, energy storage deployment, and network acceptance.

[0027] Specifically, in step S3, candidate conventional turbine units are combined with candidate wind-storage access areas to form candidate alternative solutions. Each candidate alternative solution represents: the... Traditional generator sets were phased out, and in the [number]th [year]... Several candidate areas are connected to wind power and energy storage.

[0028] Unlike evaluating the suitability of a single conventional turbine unit for decommissioning, this embodiment evaluates the decommissioning of conventional turbine units and the selection of wind and energy storage access areas as a whole. Therefore, different combinations of conventional turbine units with different access areas may result in different substitution mode damping sensitivities and substitution priorities.

[0029] Specifically, in step S4, eigenvalue analysis is performed on the current system state matrix to obtain the system eigenvalues ​​and their corresponding left and right eigenvectors. The damping ratio for each mode is calculated based on the real and imaginary parts of the eigenvalues. The damping ratio calculation formula is as follows: ; In the formula, For the first After the replacement of the first round Real part of each modal eigenvalue; For the first After the replacement of the first round The imaginary part of each modal eigenvalue; For the first After the replacement of the first round Modal damping ratio.

[0030] In one implementation, select Low-frequency electromechanical oscillation modes within the specified frequency range are used as the evaluation objects. If multiple electromechanical oscillation modes exist within this frequency range, the mode with the lower damping ratio is given more weight in subsequent calculations.

[0031] Specifically, in step S5, for the part by the first Taiwan conventional units and the first Candidate alternatives comprised of several wind and energy storage access areas are set with a small replacement ratio increment. In the first Traditional generator units will be phased out in small proportions and in the [year]... After wind power and energy storage are connected to each region, the system small signal state matrix is ​​re-established.

[0032] Furthermore, the perturbation of the state matrix per unit substitution ratio caused by the candidate alternative is: ; In the formula, For the first Traditional generator units were phased out and in the 1st Disturbance in the state matrix of unit substitution ratio caused by the integration of wind power and energy storage in a region; For a small substitution ratio increase; This state matrix perturbation is used to characterize the impact of wind power and energy storage as a candidate alternative on the dynamic characteristics of the system after the traditional units are decommissioned.

[0033] Specifically, in step S6, the sensitivity of the candidate alternative to the change of the eigenvalue of the electromechanical oscillation mode is calculated based on the state matrix disturbance caused by the candidate alternative and the left and right eigenvectors corresponding to the current electromechanical oscillation mode.

[0034] Furthermore, the sensitivity to changes in eigenvalues ​​is: ; In the formula, For candidate alternatives to the first Sensitivity to changes in the eigenvalues ​​of individual electromechanical oscillation modes; and The first The left and right feature vectors corresponding to each modality; This step allows the system state matrix changes caused by candidate alternatives to be projected onto a specified electromechanical oscillation mode, thereby obtaining the direction and degree of influence of the candidate alternative on the eigenvalues ​​of that mode.

[0035] Specifically, in step S7, the eigenvalue change sensitivity is decomposed into real part change sensitivity and imaginary part change sensitivity, and further mapped to damping ratio change sensitivity. Candidate alternatives for the first... The sensitivity of the damping ratio of each electromechanical oscillation mode is: ; In the formula, For candidate alternatives to the first Sensitivity of damping ratio for individual electromechanical oscillation modes; and These are the sensitivity to changes in the real and imaginary parts of the eigenvalues, respectively. when When, it indicates that the candidate alternative is beneficial to improving the damping of the electromechanical oscillation mode; when When this occurs, it indicates that the candidate alternative may reduce the damping of the electromechanical oscillation mode.

[0036] Furthermore, when multiple electromechanical oscillation modes exist within a preset frequency range, the damping ratio sensitivity of each electromechanical oscillation mode is weighted and summed to obtain the comprehensive alternative mode damping sensitivity of the candidate alternative scheme: ; In the formula, The overall alternative modal damping sensitivity of the candidate alternatives; For the first The weights of each electromechanical oscillation mode are assigned; the lower the damping ratio, the higher the weight of the electromechanical oscillation mode.

[0037] Specifically, in step S8, the unit's replaceable output coefficient and the access power flow margin coefficient are further combined to construct a comprehensive alternative ranking score for candidate alternative schemes.

[0038] Furthermore, the unit's substitutable output coefficient is: ; In the formula, For the first Wheel of Life The output coefficient of the traditional generator unit can be replaced; For the first Wheel of Life The current active power output of the traditional generator units in Taiwan; For the first A pool of candidate conventional generating units; For the first Wheel of Life The current contributions of the traditional generator sets in Taiwan are commendable.

[0039] Furthermore, the access power flow margin coefficient is: ; In the formula, For the first Access flow margin coefficient of candidate alternatives in the round; The first [unclear] was determined after comprehensively considering node voltage constraints, line power flow constraints, and regional resource access limits. The upper limit of wind power and energy storage capacity allowed to be accessed in each candidate area; For the first The first replacement The wind power and energy storage capacity already connected in each candidate access area; For the first Wheel of Life Replacement capacity of traditional units.

[0040] Among them, the unit can be replaced by the output coefficient to characterize the first The available active power capacity from traditional generating units; the alternative mode damping sensitivity is used to characterize the direction of improvement or deterioration of electromechanical oscillation mode damping by candidate alternatives; the access power flow margin coefficient is used to characterize the first... Network margin for candidate regions to accommodate wind power and energy storage.

[0041] Furthermore, after normalizing and aligning the above indicators, the comprehensive alternative ranking score is as follows: ; In the formula, For the first A comprehensive alternative ranking score for each round of candidate alternatives; The normalized unit replaceable output coefficient; This represents the normalized alternative mode damping sensitivity. The normalized access power flow margin coefficient; For the corresponding weights.

[0042] In one implementation, since this invention focuses on the impact of traditional unit decommissioning and wind-storage integration on electromechanical oscillation stability, the weight of the alternative modal damping sensitivity can be higher than other indicators. Based on the comprehensive alternative ranking score, all candidate alternative schemes are sorted in descending order, and the candidate alternative scheme with the highest score is selected as the priority alternative scheme for the current round.

[0043] Specifically, in step S9, after determining the priority replacement scheme for the current round, the wind power installed capacity and energy storage capacity are determined based on the replacement capacity of the replaced traditional units.

[0044] Furthermore, the replacement capacity of the replaced traditional turbines can be determined based on the current replacement ratio and the original active power output of the traditional turbines. The wind power installed capacity is determined based on the replacement capacity of the traditional turbines and the wind power capacity reliability coefficient. ; In the formula, For the first The installed capacity of wind power configured in the priority access area; For the first Replacement capacity of traditional generating units; This is the reliability coefficient of the wind power capacity in the region.

[0045] Furthermore, a substitution ratio adjustment step size and a minimum substitution ratio are set. The minimum substitution ratio is the smallest non-zero substitution ratio allowed when performing progressive substitution trials on the current candidate substitution scheme, and is preset based on the substitution ratio search step size and capacity planning accuracy. When the substitution scheme under the current substitution ratio does not meet the preset target constraint, the substitution ratio is gradually reduced according to the substitution ratio adjustment step size and the substitution trial is re-performed until the substitution scheme meets the preset target constraint, or the substitution ratio is reduced to the minimum substitution ratio.

[0046] Energy storage capacity is determined based on the replacement capacity of traditional generating units and damping compensation requirements: ; In the formula, For the first The energy storage capacity configured in the priority access area; This refers to the basic configuration factor for energy storage capacity. This is the damping compensation coefficient; This is the lower limit of the set electromechanical modal damping ratio; This is to replace the predicted value of the post-critical electromechanical mode damping ratio.

[0047] Furthermore, the energy storage capacity can be determined based on the energy storage power capacity, support duration, and energy storage charging and discharging efficiency; wind power is mainly used to replace the active power capacity after the traditional units are phased out, while energy storage is mainly used to provide rapid power compensation, damping support, frequency support, and voltage support.

[0048] Specifically, in step S10, the wind power installed capacity and energy storage capacity determined in the current cycle are connected to the system model, and power flow calculation and small signal stability analysis are performed again.

[0049] Furthermore, to ensure the safe and stable operation of the system after the traditional units are decommissioned and the wind and energy storage systems are connected, the following constraints are checked on the alternative solutions: Node voltage constraints: , ; In the formula, For the first After the wheel replacement node The voltage amplitude; and These are the minimum and maximum voltage limits allowed for the node, respectively; For the system node set; Power flow constraints on the line: , ; In the formula, For the first After the replacement of the wheel, the line The meritorious trend; This represents the maximum allowable transmission capacity of the line. For the set of routes; Wind power capacity constraints: ; In the formula, For the first The installed capacity of wind power in the alternative wheel configuration; For the first The maximum wind power capacity allowed to be connected in the candidate wind and energy storage access area; Energy storage capacity constraints include energy storage power constraints and energy storage energy constraints; Energy storage power constraints: ; In the formula, For the first The energy storage capacity configured for the wheel replacement scheme; For the first The maximum energy storage capacity allowed to be connected to the candidate wind and energy storage access areas; Energy storage energy constraints: ; In the formula, For the first The energy storage capacity configured for wheel replacement solutions; For the first The maximum energy storage capacity allowed to be connected to the candidate wind and energy storage access areas; Small-signal stability constraints: ; In the formula, For the first After the replacement of the first round Real part of each modal eigenvalue; Electromechanical modal damping constraints: ; In the formula, For the first After the replacement of the first round Modal damping ratio; This is the lower limit of the set electromechanical modal damping ratio.

[0050] If the replaced system satisfies the node voltage constraints, line power flow constraints, wind power capacity constraints, energy storage capacity constraints, small signal stability constraints, and electromechanical mode damping constraints, then the current round of replacement scheme is accepted, and the replaced traditional unit, wind-storage access area, replacement ratio, wind power installed capacity, energy storage power capacity, energy storage energy capacity, and stability index after replacement are recorded. Furthermore, the alternative solutions accepted in the current round are updated in the system operation model, and the next round of progressive replacement process is initiated to redetermine the priority alternative solutions for the next round.

[0051] If the system after substitution does not meet any of the above constraints, the substitution scheme at the current substitution ratio is rejected. The substitution ratio is then gradually reduced while keeping the replaced traditional turbines and wind-storage access areas unchanged. The corresponding wind power installed capacity and energy storage capacity are re-determined, and power flow calculations and small-signal stability analyses are performed again. If the above constraints are met after reducing the substitution ratio, the adjusted substitution scheme is accepted. If the above constraints are still not met after the substitution ratio of the current candidate scheme is reduced to the set minimum substitution ratio, the candidate scheme is deemed unacceptable in the current round, and the next candidate scheme in the comprehensive substitution ranking is selected for a new substitution trial. If all candidate substitution schemes in the current round fail to meet the above constraints at the set minimum substitution ratio, the progressive substitution is stopped, and the scheme accepted in the previous round is determined as the maximum acceptable substitution scheme under the current system conditions.

[0052] Specifically, in step S11, after each round of alternative solutions is accepted, the power flow calculation is re-performed to obtain the node voltage, line power flow, and current active power output of the remaining candidate traditional units after the alternative. Based on the updated current active power output, the unit replacement output coefficient of each candidate traditional unit is recalculated. Simultaneously, the system state matrix is ​​re-established based on the new operating point after the alternative, and the computer's electrical oscillation modes, mode damping ratios, and alternative mode damping sensitivities are calculated. Based on this, the comprehensive alternative ranking score is recalculated to determine the next round of priority alternative solutions.

[0053] Specifically, in step S12, if the current candidate alternative still exhibits any of the following conditions under the set minimum substitution ratio, then the candidate alternative is deemed unacceptable in the current round: the existence of an oscillating mode or non-oscillating mode with a non-negative real part of the eigenvalue; the damping ratio of the electromechanical oscillating mode is lower than the set lower limit; the node voltage exceeds the limit; the line power flow exceeds the limit; the wind power access capacity exceeds the regional upper limit; the energy storage capacity or energy capacity exceeds the configuration upper limit; or the power flow calculation does not converge. The candidate alternatives in the comprehensive substitution ranking are then tested sequentially. If all candidate alternatives in the current round exhibit any of the above conditions under the set minimum substitution ratio, then the substitution stop boundary is reached, and the progressive substitution is stopped.

[0054] After ceasing progressive replacement, the previously accepted solution is determined as the maximum acceptable replacement solution, and the capacity planning results for the coordinated replacement of traditional units by wind power and energy storage are output.

[0055] Specifically, in step S12, the progressive replacement is stopped when the replacement ratio is increased or the replacement of the next traditional unit leads to any of the following situations: the existence of an oscillating mode or non-oscillating mode with a non-negative real part of the eigenvalue; the damping ratio of the electromechanical oscillating mode is lower than the set lower limit; the node voltage exceeds the limit; the line power flow exceeds the limit; the wind power access capacity exceeds the regional upper limit; the energy storage power capacity or energy capacity exceeds the configuration upper limit; or the power flow calculation does not converge.

[0056] After ceasing progressive replacement, the previously accepted solution is determined as the maximum acceptable replacement solution, and the capacity planning results for the coordinated replacement of traditional units by wind power and energy storage are output.

[0057] Furthermore, the capacity planning results include: the number of the traditional units to be replaced in each round, the wind power and energy storage access areas in each round, the replacement ratio of traditional units in each round, the capacity of traditional units to be replaced in each round, the installed capacity of wind power in each round, the power capacity of energy storage in each round, the energy capacity of energy storage in each round, the electromechanical oscillation mode damping ratio before and after replacement in each round, the mode damping sensitivity of replacement in each round, the maximum acceptable replacement capacity, the reasons for stopping replacement, the system power flow verification results after replacement, and the small signal stability verification results.

[0058] Furthermore, to achieve coordinated determination of the replacement sequence of traditional generating units, wind and storage access areas, and replacement capacity, this embodiment integrates the above steps and proposes a progressive replacement capacity planning algorithm based on multi-index ranking, such as... Figure 2 As shown, the algorithm includes the following steps: A1: Input system parameters, traditional unit parameters, wind storage candidate area parameters, and constraints; A2: Establish a baseline power flow model and a small-signal dynamic model; A3: Calculate the current state matrix ; A4: Screening candidate conventional turbine units and candidate wind-storage access areas; A5: Construct candidate alternatives; A6: Screen electromechanical oscillation modes and calculate damping ratios; A7: Conduct small-scale substitution trials for candidate alternatives; A8: Calculate the sensitivity to state matrix perturbations and eigenvalue changes; A9: Computer group can replace output coefficient, replace modal damping sensitivity, and access power flow margin coefficient; A10: Calculate the comprehensive alternative ranking score; A11: Select the candidate alternative with the highest comprehensive alternative ranking score; A12: Determine the substitution ratio, wind power installed capacity, energy storage power capacity, and energy storage capacity; A13: Perform power flow calculations and small-signal stability analysis; A14: Determine whether the preset target constraints are met; A15: If the constraints are met, accept the alternative solution for this round, update the system running point and state matrix, and proceed to the next round of substitution; if the constraints are not met and the current substitution ratio is higher than the set minimum substitution ratio, reduce the substitution ratio and recalculate; if the constraints are still not met after reducing to the set minimum substitution ratio, select the next candidate alternative solution in the comprehensive substitution ranking and recalculate. A16: If none of the candidate alternatives in the current round meet the constraints under the set minimum replacement ratio, then stop the progressive replacement and determine the accepted alternative from the previous round as the maximum acceptable alternative. A17: Output the replacement sequence of traditional units, the replacement capacity of each round, the installed capacity of wind power, the power capacity of energy storage, the energy storage capacity, the electromechanical mode damping ratio after replacement, and the maximum acceptable replacement capacity; Through the algorithm described above, this embodiment considers capacity substitution value, network access margin, and modal damping impact simultaneously in each round of progressive substitution. Specifically, the unit replacement output coefficient avoids prioritizing the replacement of traditional units with insufficient capacity; the access power flow margin coefficient prevents node voltage or line power flow exceeding limits after wind power and energy storage are integrated; and the substitution modal damping sensitivity prevents a decrease in electromechanical oscillation mode damping after traditional units are phased out. Therefore, the progressive substitution algorithm can update the substitution ranking and capacity configuration results round by round while meeting the system's preset target constraints, ultimately determining the order of traditional unit replacements, the wind and energy storage access areas, and the maximum acceptable substitution capacity.

[0059] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made to the technical solutions of the present invention by those skilled in the art without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A method for capacity planning of wind power and energy storage synergistically replacing traditional generating units based on multi-index ranking, characterized in that, include: Obtain candidate traditional turbine units and candidate wind storage access areas, and construct candidate alternative solutions; The sensitivity of eigenvalue changes is calculated using the state matrix perturbation caused by the candidate alternatives. The sensitivity of alternative mode damping is calculated based on the sensitivity of eigenvalue changes. A comprehensive alternative ranking score is generated for the candidate alternatives. The candidate alternative with the highest comprehensive alternative ranking score is selected as the priority alternative for the current round. Based on the benchmark operation model, power flow calculation and small-signal stability analysis are performed on the alternative capacity of the preferred alternative scheme to obtain the benchmark operation results. The benchmark operation results are compared and analyzed with the preset target constraints to obtain the capacity planning results of the maximum acceptable alternative scheme.

2. The method for synergistic replacement of traditional generating unit capacity planning based on multi-index ranking of wind power and energy storage as described in claim 1, characterized in that, Calculating the sensitivity to changes in the eigenvalues ​​includes: Constructing the state matrix perturbation caused by the candidate alternative: ； in, For the first Traditional generator units were phased out and in the 1st The state matrix disturbance caused by the integration of wind power and energy storage in a region. For a small substitution ratio increase, For the first The state matrix of the system after the wheel replacement; The sensitivity to eigenvalue changes is calculated using the perturbation of the state matrix: ； in, For candidate alternatives to the first Sensitivity to changes in the eigenvalues ​​of individual electromechanical oscillation modes and The first The left and right feature vectors corresponding to each modality.

3. The method for synergistic replacement of traditional generating unit capacity planning by wind power and energy storage based on multi-index ranking as described in claim 1, characterized in that, Calculating the alternative modal damping sensitivity includes: Small-signal eigenvalue analysis is performed on the planned power system to screen electromechanical oscillation modes, and the damping ratio of the electromechanical oscillation modes is calculated: ； in, For the first After the replacement of the first round The real part of each modal eigenvalue. For the first After the replacement of the first round The imaginary part of each modal eigenvalue. For the first After the replacement of the first round Modal damping ratio; The alternative mode damping sensitivity is calculated based on the sensitivity to the change in the eigenvalue and the damping ratio of the electromechanical oscillation mode: ； in, For candidate alternatives to the first Sensitivity of damping ratio of individual electromechanical oscillation modes; when When, it indicates that the candidate alternative is beneficial to improving the damping of the electromechanical oscillation mode. When this occurs, it indicates that the candidate alternative may reduce the damping of the electromechanical oscillation mode. and These are the real and imaginary parts of the sensitivity to changes in eigenvalues, respectively. and The first The left and right feature vectors corresponding to each modality.

4. The method for synergistic replacement of traditional generating unit capacity planning based on multi-index ranking of wind power and energy storage as described in claim 1, characterized in that, The comprehensive alternative ranking score for generating the candidate alternatives includes: ； ； ； ； in, For the first The comprehensive alternative ranking score of the round of candidate alternatives, The normalized unit replaceable output coefficient, This is the normalized alternative mode damping sensitivity. This is the normalized access power flow margin coefficient. For the corresponding weights, The comprehensive alternative modal damping sensitivity of the candidate alternatives. For the first A pool of candidate conventional generating units, For the first Weights of each electromechanical oscillation mode For the first Wheel of Life The output coefficient of traditional Taiwanese generator units can be replaced. For the first Wheel of Life The current active power output of Taiwan's traditional generating units For the first A pool of candidate conventional generating units, For the first Wheel of Life The current contributions of the traditional aircraft carriers in Taiwan's candidate fleet are noteworthy. For the first Access flow margin coefficient of candidate alternatives in the round, The first [unclear] was determined after comprehensively considering node voltage constraints, line power flow constraints, and regional resource access limits. The upper limit of wind power and energy storage capacity allowed for access in each candidate area. For the first The first replacement The wind power and energy storage capacity already connected in each candidate access area For the first Wheel of Life Replacement capacity of traditional units.

5. The method for synergistic replacement of traditional generating unit capacity planning based on multi-index ranking of wind power and energy storage as described in claim 1, characterized in that, The alternative capacity includes: ； ； in, For the first The wind power installed capacity configured in the priority access area, For the first Replacement capacity of traditional generating units; The reliability coefficient of wind power capacity in this region. For the first The energy storage capacity configured in the priority access area, This is the basic configuration factor for energy storage capacity. This is the damping compensation coefficient. The lower limit of the set electromechanical modal damping ratio, This is to replace the predicted value of the post-critical electromechanical mode damping ratio.

6. The method for synergistic replacement of traditional generating unit capacity planning based on multi-index ranking of wind power and energy storage as described in claim 1, characterized in that, The benchmark results obtained include: Based on the steady-state power flow sub-model in the benchmark operation model, power flow calculation is performed on the alternative capacity in the preferred alternative scheme to obtain node voltage, line power flow, active power output and reactive power output of traditional units; Based on the small-signal dynamic sub-model in the benchmark operating model, small-signal stability analysis is performed on the alternative capacity in the preferred alternative scheme to obtain system characteristic values, electromechanical oscillation modes, modal damping ratios, and the impact of candidate alternative schemes on system stability.

7. The method for synergistic replacement of traditional generating unit capacity planning based on multi-index ranking of wind power and energy storage as described in claim 1, characterized in that, The capacity planning results for obtaining the maximum acceptable alternative include: The benchmark operation results are compared and analyzed with preset target constraints. If the benchmark operation results meet the preset target constraints, the current round's replacement scheme is accepted. If the benchmark operation results do not meet the preset target constraints, the replacement ratio of the current candidate replacement scheme is reduced and re-analyzed. If the replacement ratio of the current candidate replacement scheme is reduced to the set minimum replacement ratio and still does not meet the preset target constraints, the current candidate replacement scheme is determined to be unacceptable, and the next candidate replacement scheme in the comprehensive replacement ranking is selected for re-analysis. If all candidate replacement schemes in the current round cannot meet the preset target constraints at the set minimum replacement ratio, the progressive replacement is stopped, and the scheme accepted in the previous round is determined as the maximum acceptable replacement scheme under the current system conditions. The capacity planning result for the coordinated replacement of traditional units by wind power and energy storage is output.

8. The method for synergistic replacement of traditional generating unit capacity planning based on multi-index ranking of wind power and energy storage as described in claim 7, characterized in that, The minimum substitution ratio is the minimum non-zero substitution ratio allowed in the progressive substitution trial calculation, which can be preset according to the search step size and capacity planning accuracy based on the substitution ratio.

9. The method for synergistic replacement of traditional generating unit capacity planning by wind power and energy storage based on multi-index ranking as described in claim 7, characterized in that, The preset target constraints include: Node voltage constraints: , ； In the formula, For the first After the wheel replacement node The voltage amplitude; and These are the minimum and maximum voltage limits allowed for the node, respectively; For the system node set; Power flow constraints on the line: , ； In the formula, For the first After the replacement of the wheel, the line The meritorious trend; This represents the maximum allowable transmission capacity of the line. For the set of routes; Wind power capacity constraints: ； In the formula, For the first The installed capacity of wind power in the alternative wheel configuration; For the first The maximum wind power capacity allowed to be connected in the candidate wind and energy storage access area; Energy storage capacity constraints include energy storage power constraints and energy storage energy constraints; Energy storage power constraints: ； In the formula, For the first The energy storage capacity configured for the wheel replacement scheme; For the first The maximum energy storage capacity allowed to be connected to the candidate wind and energy storage access areas; Energy storage energy constraints: ； In the formula, For the first The energy storage capacity configured for wheel replacement solutions; For the first The maximum energy storage capacity allowed to be connected to the candidate wind and energy storage access areas; Small-signal stability constraints: ； In the formula, For the first After the replacement of the first round Real part of each modal eigenvalue; Electromechanical modal damping constraints: ； In the formula, For the first After the replacement of the first round Modal damping ratio; This is the lower limit of the set electromechanical modal damping ratio.

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