Method and device for calculating security margin of dc tie line based on sensitivity analysis

Abstract

This application relates to a method and apparatus for calculating the safety margin of DC tie lines based on sensitivity analysis. The method includes: acquiring grid forecast data, power plant operation plan data, and grid maintenance data corresponding to the power system; obtaining the cross-sectional sensitivity of each DC tie line based on the grid forecast data, power plant operation plan data, and grid maintenance data; obtaining the remaining transmission margin of any DC tie line based on its transmission limit and future plan data; obtaining the current restricted margin of each DC tie line relative to other DC tie lines based on the cross-sectional sensitivity of each tie line; and calculating the intersection between the restricted margin of each cross-section and the remaining transmission margin of the tie line to obtain the final safety margin. This method enables dynamic monitoring of the final safety margin of tie lines, improving the execution efficiency and safety level of grid dispatching.

Description

Technical Field

[0001] This application relates to the field of computer technology, and in particular to a method, apparatus, computer device, storage medium, and computer program product for calculating the safety margin of DC tie lines based on sensitivity analysis. Background Technology

[0002] With the development of computer technology, power grid security technology has emerged. To ensure power grid security, a grid-level dispatching agency is needed. This agency publishes the DC tie-line power plan for the following day before the operation date. Based on the operation status of each provincial power grid within the interconnected grid, and in order to achieve goals such as provincial power balance, promote the consumption of new energy sources, and optimize the allocation of power resources, the dispatching agency will modify the tie-line plan in real time within the day.

[0003] In traditional technologies, the intraday margin judgment of DC tie lines mainly relies on the personal experience of dispatchers. It lacks the ability to dynamically track factors such as fluctuations in renewable energy output and load changes, and has not yet achieved unified optimization calculations. Safety verification is completed manually by dispatchers, which is time-consuming and prone to omissions and errors. As a result, the final safety margin of DC tie lines obtained is significantly off, leading to a low level of safety in power grid dispatching. Summary of the Invention

[0004] Therefore, it is necessary to provide a method, apparatus, computer equipment, computer-readable storage medium, and computer program product for calculating the safety margin of DC tie lines based on sensitivity analysis, which can improve the safety level of power grid dispatching, in response to the above-mentioned technical problems.

[0005] In a first aspect, this application provides a method for calculating the safety margin of DC tie lines based on sensitivity analysis. The method includes: acquiring grid forecast data, power plant operation plan data, and grid maintenance data corresponding to the power system; and obtaining the cross-sectional sensitivity of each DC tie line in the power system based on the grid forecast data, the power plant operation plan data, and the grid maintenance data; obtaining the remaining transmission margin of the DC tie line based on any given DC tie line, according to the transmission limit and future plan data of the DC tie line; obtaining the current cross-sectional constraint margin of the DC tie line relative to the other DC tie lines based on the cross-sectional sensitivity of each tie line; and calculating the intersection between the constraint margin of each cross-section and the remaining transmission margin of the tie line to obtain the final safety margin of the DC tie line.

[0006] Secondly, this application also provides a DC tie-line safety margin calculation device based on sensitivity analysis. The device includes: a tie-line section sensitivity acquisition module, used to acquire grid forecast data, power plant operation plan data, and grid maintenance data corresponding to the power system, and to obtain the tie-line section sensitivity corresponding to each DC tie-line in the power system based on the grid forecast data, the power plant operation plan data, and the grid maintenance data; a tie-line intermediate margin calculation module, used to obtain the remaining transmission margin of any DC tie-line based on the transmission limit and future plan data of the DC tie-line; and to obtain the current DC tie-line's section constraint margin relative to other DC tie-lines based on the section sensitivity of each tie-line; and a final safety margin acquisition module, used to calculate the intersection between the section constraint margin and the remaining transmission margin of the tie-line to obtain the final safety margin corresponding to the DC tie-line.

[0007] Thirdly, this application also provides a computer device. The computer device includes a memory and a processor. The memory stores a computer program, and the processor, when executing the computer program, performs the following steps: acquiring power grid forecast data, power plant operation plan data, and power grid maintenance data corresponding to the power system; and based on the power grid forecast data, the power plant operation plan data, and the power grid maintenance data, obtaining the cross-sectional sensitivity of each DC tie line in the power system; based on any one of the DC tie lines, obtaining the remaining transmission margin of the corresponding DC tie line according to the transmission limit and future plan data of the DC tie line; and based on the cross-sectional sensitivity of each tie line, obtaining the current cross-sectional constraint margin of the current DC tie line relative to the cross-sectional constraints of other DC tie lines; and calculating the intersection between the cross-sectional constraint margins and the remaining transmission margin of the tie line to obtain the final safety margin corresponding to the DC tie line.

[0008] Fourthly, this application also provides a computer-readable storage medium. The computer-readable storage medium stores a computer program thereon, which, when executed by a processor, performs the following steps: acquiring grid forecast data, power plant operation plan data, and grid maintenance data corresponding to the power system; and based on the grid forecast data, the power plant operation plan data, and the grid maintenance data, obtaining the cross-sectional sensitivity of each DC tie line in the power system; based on any one of the DC tie lines, obtaining the remaining transmission margin of the DC tie line corresponding to the DC tie line according to the DC tie line transmission limit and the future plan data of the DC tie line; and based on the cross-sectional sensitivity of each tie line, obtaining the current cross-sectional constraint margin of the DC tie line relative to the cross-sectional constraints of the other DC tie lines; and calculating the intersection between the cross-sectional constraint margins and the remaining transmission margin of the tie line to obtain the final safety margin corresponding to the DC tie line.

[0009] Fifthly, this application also provides a computer program product. The computer program product includes a computer program that, when executed by a processor, performs the following steps: acquiring grid forecast data, power plant operation plan data, and grid maintenance data corresponding to the power system; and obtaining the sensitivity of each DC tie line section corresponding to each DC tie line in the power system based on the grid forecast data, the power plant operation plan data, and the grid maintenance data; based on any one of the DC tie lines, obtaining the remaining transmission margin of the DC tie line corresponding to the DC tie line according to the transmission limit of the DC tie line and the future plan data of the DC tie line; and obtaining the current DC tie line's constraint margin relative to the other DC tie lines based on the sensitivity of each tie line section; and calculating the intersection between the constraint margin of each section and the remaining transmission margin of the tie line to obtain the final safety margin corresponding to the DC tie line.

[0010] The aforementioned method, apparatus, computer equipment, storage medium, and computer program product for calculating the safety margin of DC tie lines based on sensitivity analysis acquires grid forecast data, power plant operation plan data, and grid maintenance data corresponding to the power system. Based on these data, the sensitivity of each DC tie line section in the power system is obtained. For any given DC tie line, the remaining transmission margin is obtained based on its transmission limit and future planning data. Furthermore, based on the sensitivity of each tie line section, the current DC tie line's limited margin relative to other DC tie lines is obtained. Finally, the intersection of each limited margin and the remaining transmission margin of the tie line is calculated to obtain the final safety margin of the DC tie line.

[0011] By comprehensively assessing the cross-sectional constraints of tie lines through cross-sectional generation and sensitivity analysis, the final safety margin analysis is achieved. This approach is highly targeted and practical, filling a gap in specialized services for the final safety margin analysis of DC tie lines in the field of planned dispatching between different power grids. It also solves problems such as low automation, long processing time, and the risk of cross-sectional exceedance in the original business model, enabling dynamic monitoring of the final safety margin of tie lines and improving the execution efficiency and safety level of power grid dispatching. Attached Figure Description

[0012] Figure 1 This is an application environment diagram of a DC tie-line safety margin calculation method based on sensitivity analysis in one embodiment;

[0013] Figure 2 This is a flowchart illustrating a method for calculating the safety margin of a DC tie line based on sensitivity analysis in one embodiment.

[0014] Figure 3 This is a flowchart illustrating the method for obtaining the constraint margin of each section in one embodiment;

[0015] Figure 4 This is a flowchart illustrating a method for determining the remaining adjustment margin of a cross section in one embodiment;

[0016] Figure 5 This is a flowchart illustrating the method for obtaining the constraint margin of each section in another embodiment;

[0017] Figure 6 This is a flowchart illustrating a method for obtaining the sensitivity of a connecting line section in one embodiment;

[0018] Figure 7 This is a flowchart illustrating the method for obtaining the final safety margin in one embodiment;

[0019] Figure 8 This is a structural block diagram of a DC tie-line safety margin calculation device based on sensitivity analysis in one embodiment;

[0020] Figure 9 This is an internal structural diagram of a computer device in one embodiment. Detailed Implementation

[0021] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0022] This application provides a method for calculating the safety margin of DC tie lines based on sensitivity analysis, which can be applied to, for example... Figure 1 In the application environment shown, terminal 102 communicates with server 104 via a network. A data storage system can store the data that server 104 needs to process. The data storage system can be integrated onto server 104 or placed on the cloud or other network servers. Server 104 obtains grid forecast data, power plant operation plan data, and grid maintenance data corresponding to the power system from terminal 102. Based on the grid forecast data, power plant operation plan data, and grid maintenance data, it obtains the sensitivity of each DC tie line section in the power system. Based on any DC tie line, according to the DC tie line transmission limit and future plan data, it obtains the remaining transmission margin of the corresponding DC tie line. Based on the sensitivity of each tie line section, it obtains the current DC tie line's limited margin relative to other DC tie lines. It calculates the intersection between the limited margin of each section and the remaining transmission margin of the tie line to obtain the final safety margin of the DC tie line. The terminal 102 can be, but is not limited to, various personal computers, laptops, smartphones, tablets, IoT devices, and portable wearable devices. IoT devices can include smart speakers, smart TVs, smart air conditioners, and smart in-vehicle systems. Portable wearable devices can include smartwatches, smart bracelets, and head-mounted devices. The server 104 can be implemented using a standalone server or a server cluster consisting of multiple servers.

[0023] In one embodiment, such as Figure 2 As shown, a method for calculating the safety margin of DC tie lines based on sensitivity analysis is provided, and this method is applied to... Figure 1 Taking the server in the example, the following steps are included:

[0024] Step 202: Obtain the power grid forecast data, power plant operation plan data, and power grid maintenance data corresponding to the power system, and obtain the cross-sectional sensitivity of each DC tie line in the power system based on the power grid forecast data, power plant operation plan data, and power grid maintenance data.

[0025] Among them, power grid forecast data can be the predicted values ​​of various parameters in the future power system obtained by combining historical data with artificial intelligence models or data forecasting models related to the power grid.

[0026] Among them, the power plant operation plan data can be the plan data formulated by the power plant or distribution plant in the power system during future operation. This data can be calculated by artificial intelligence models or simulated by mathematical models adapted to the production and operation plan of the power plant or distribution plant.

[0027] Among them, power grid maintenance data can be generated through the maintenance of the power system. Power grid maintenance data can be collected manually and then entered into the server, or it can be collected through intelligent data acquisition terminals.

[0028] DC tie lines can connect two power systems, two inter-provincial power grids, two substations, or even two distribution stations, fully utilizing the power generation and supply capabilities of both parties and promoting the optimal allocation of resources. DC tie lines can be divided into single-pole tie lines, double-pole tie lines, and same-pole tie lines.

[0029] Among them, the cross-sectional sensitivity of the tie line can be the ratio of the impact on the cross-section when the power of the channel corresponding to the DC tie line increases or decreases.

[0030] Specifically, in response to the instruction to calculate the safety margin of the DC tie line, the server obtains the corresponding power grid forecast data, power plant operation plan data and power grid maintenance data from the terminal. The power grid forecast data includes ultra-short-term system load forecast data and ultra-short-term bus load forecast data, and the power plant operation plan data includes the future plan data of the power plants generated by each electrical island in the interconnected power grid.

[0031] Using ultra-short-term system load forecast data and ultra-short-term bus load forecast data from the power grid forecasting data, AC power flow calculations can be performed to obtain the initial power flow of each DC tie-line section corresponding to the power system. When performing AC power flow calculations, it is necessary to use the nodal voltage method, the Newton-Raphson method, or the PQ decoupling method, with the nodal admittance matrix Y as the mathematical model of the power network. Nodal voltage U i and node injection current I i This is related to the node voltage equations. Under known operating conditions, the power injected into the nodes is not the node current, but rather the load and generator power, and this power generally does not change with node voltage variations. The relationship between the injected power and injected current at each node is as follows:

[0032] S i =P i +jQ i =U i I i

[0033] In the formula, P i and Q i Let P be the active power and reactive power injected into the network by node i, respectively. When i is a generator node, P... i >0; when i is a load node, P i <0; when i is a passive node P i =0, Q i =0;Ui and I i These are the node voltage phasors U. i and node injection current phasor I i The conjugate of . There are n nonlinear complex equations, which are the basic equations for power flow calculation. It can establish 2n real-form power equations in either rectangular or polar coordinates.

[0034] Given the network wiring and branch parameters, the node admittance matrix Y in AC power flow calculations can be derived. The injected active power P is the variable representing the system's operating state in the AC power flow equations. i Reactive power Q i and node voltage phasor U i (Amplitude Ui and phase angle δ) i A power grid with n nodes has 4n variables, but only 2n power equations; therefore, 2n operating state variables must be given. Depending on the given node variables, there are three types of nodes.

[0035] PU node: (Voltage control bus) Active power P i and voltage amplitude U i Given. This type of node is equivalent to a generator bus node, or a substation bus equipped with a synchronous condenser or static compensator. The active power P injected into the PQ node is... i and reactive power Q i It is a given value. It corresponds to a load node in a real power system, or a generator bus with given active and reactive power. A slack node: used to balance the power of the entire power grid. The voltage amplitude U of a slack node. i and phase angle δ i It is given, and its phase angle is usually used as the reference point, that is, its voltage phase angle is taken as zero. An independent power grid has only one slack node. The corresponding power system can be obtained.

[0036] Based on the initial power flow of the tie line section, the future power plant plan data generated by each electrical island in the interconnected power grid in the power plant operation plan data, and the power grid maintenance data, the ratio of the impact of the power increase or decrease of the corresponding channel of the DC tie line on the section is calculated, and the tie line section sensitivity corresponding to each DC tie line in the power system is obtained.

[0037] Step 204: Based on any DC tie line, obtain the remaining transmission margin of the DC tie line according to the transmission limit of the DC tie line and the future planning data of the DC tie line; and obtain the current DC tie line's constraint margin relative to the other DC tie lines according to the sensitivity of each tie line section.

[0038] Among them, the DC tie line transmission limit can be the power transmission limit corresponding to the DC tie line in the process of transmitting electrical energy, also known as the total transfer capacity (TTC); at the same time, in addition to the power transmission limit, the voltage and current in the transmission process also have transmission limits.

[0039] Among them, the future planning data of DC tie lines can be the planned values ​​obtained by using artificial intelligence models or mathematical models for DC tie lines to predict future data based on previous data, to plan the future power data, current data and voltage data of DC tie lines.

[0040] Among them, the residual transmission margin of the tie line can be the adjustable margin of the residual power transmission corresponding to the DC tie line in the process of transmitting electrical energy. In addition to the margin of power transmission, the voltage and current in the transmission process also have residual transmission adjustable margins.

[0041] Among them, the cross-sectional constraint margin can be the power flow cross-sectional constraint transmission margin corresponding to the DC tie line during the power transmission process. In addition to the power transmission having a power flow cross-sectional constraint transmission margin, the voltage and current in the transmission process also have a power flow cross-sectional constraint transmission margin.

[0042] Specifically, for any DC tie line, based on the DC tie line's transmission limit and future planning data, the remaining transmission margin of the DC tie line can be obtained. This is achieved by subtracting the future planning data from the DC tie line's transmission limit, as expressed in the following expression:

[0043] T m，trans =T m，up -T m，plan

[0044] Among them, T m，trans It is the remaining transmission margin of the tie line, T m，up It is the transmission limit of DC tie lines, T m，plan This is data on future plans for DC tie lines.

[0045] To calculate the constraint margin of the current DC tie line relative to the corresponding sections of other DC tie lines, first, a sensitivity threshold is set for the tie line section sensitivity. Then, all tie line sections whose absolute sensitivity value is greater than the sensitivity threshold are identified, forming the set M of tie line sections of interest. staca For the set of cross-sections M of the connecting lines staca For each connecting line section, calculate the remaining adjustment margin of the section, expressed as:

[0046] S n，up =S n，up limit -S n，future

[0047] S n，dn =S n，future -S n，dn limit

[0048] The remaining adjustment margin of the cross-section includes the downward adjustment margin and the upward adjustment margin of the cross-section, S n，up It is an upward adjustment margin for the cross-section, S n，dn It is the downward adjustment margin of the cross-section, S n，up limit S is the upper limit of the cross-section of the connecting line n. n，dn limit S is the lower limit of the connecting line section n. n，future It is the initial tidal current of the connecting line section.

[0049] For the set of cross sections M of the connecting line staca For each tie line section, the DC tie lines corresponding to the tie line sections with an absolute sensitivity value greater than the sensitivity threshold are divided into two groups. The first group of DC tie line sections corresponds to the positive sensitivity sub-tie line section set M. pos The sensitivity of the selected tie-line section is positive, and the sensitivity of the negative-sensitivity sub-tie-line section set corresponding to the second set of DC tie-line sets is negative, while the sensitivity of the positive-sensitivity sub-tie-line section set M is... pos With negative sensitivity sub-connection line section set M neg There may exist an empty set.

[0050] If the set of positive sensitivity sub-connection line sections M pos The set M is an empty set, but the set of negative sensitivity sub-connection line sections. neg If it is not an empty set, then adjust the cross-section downwards by a margin S. n，dn Combined with the set of negative sensitivity sub-connection line sections M neg The corresponding tie-line remaining transmission margin T m，trans Calculate the cross-sectional constraint margin of each tie line in the set, considering the mutual sensitivity e between the tie line sections of each DC tie line:

[0051] T m，n，cons =T m，trans ·S n，dn / ∑(e m，n ·T m，trans )

[0052] Among them, T m，n，cons It is the sectional margin of DC tie line m relative to tie line section n, e m，n It is the mutual sensitivity of DC tie line m to tie line section n.

[0053] If the set of positive sensitivity sub-connection line sections M pos Not an empty set, but a set of negatively sensitive sub-connection line sections M neg If it is an empty set, then adjust the cross-section upwards by a margin S. n，up Combined with the set of positive sensitivity sub-connection line sections M pos The corresponding tie-line remaining transmission margin T m，trans Calculate the cross-sectional constraint margin of each tie line in the set, considering the mutual sensitivity e between the tie line sections of each DC tie line:

[0054] T m，n，nons =T m，trans ·S n，up / ∑(e m，n ·T m，trans )

[0055] Among them, T m，n，cons It is the sectional margin of DC tie line m relative to tie line section n, e m，n It is the mutual sensitivity of DC tie line m to tie line section n.

[0056] If the set of positive sensitivity sub-connection line sections M pos and the set of negative sensitivity sub-connection line sections M neg If none of them are empty sets, then first fix the future planning data of each DC tie line in the set of positive sensitivity sub-tie line sections, and then execute "If the set of positive sensitivity sub-tie line sections M..." pos The set M is an empty set, but the set of negative sensitivity sub-connection line sections. neg If it is not an empty set, then adjust the cross-section downwards by a margin S. n，dn Combined with the set of negative sensitivity sub-connection line sections M neg The corresponding tie-line remaining transmission margin T m，trans Calculate the cross-sectional constraint margin of each tie line in the set, considering the mutual sensitivity e between the tie line sections of each DC tie line:

[0057] T m，n，cons =T m，trans ·S n，dn / ∑(e m，n ·T m，trans )

[0058] Among them, T m，n，cons It is the sectional margin of DC tie line m relative to tie line section n, e m，n "It is the mutual sensitivity of DC tie line m to tie line section n".

[0059] Additionally, the future planning data for each DC tie line in the set of negative sensitivity sub-tie line sections is fixed, and then the process "If the set of positive sensitivity sub-tie line sections M" is executed.pos Not an empty set, but a set of negatively sensitive sub-connection line sections M neg If it is an empty set, then adjust the cross-section upwards by a margin S. n，up Combined with the set of positive sensitivity sub-connection line sections M pos The corresponding tie-line remaining transmission margin T m，trans Calculate the cross-sectional constraint margin of each tie line in the set, considering the mutual sensitivity e between the tie line sections of each DC tie line:

[0060] T m，n，cons =T m，trans ·S n，up / ∑(e m，n ·T m，trans )

[0061] Among them, T m，n，cons It is the cross-sectional margin of DC tie line m relative to tie line section n, e m，n "It is the mutual sensitivity of DC tie line m to tie line section n".

[0062] Step 206: Calculate the intersection between the constraint margin of each section and the remaining transmission margin of the tie line to obtain the final safety margin corresponding to the DC tie line.

[0063] The final safety margin can be the power safety transmission margin corresponding to the power transmission process in the DC tie line. In addition to the power transmission safety margin, the voltage and current in the transmission process also have safety transmission margins.

[0064] Specifically, the final safety margin of the DC tie line can be obtained by calculating the intersection between the constraint margin of each section and the remaining transmission margin of the tie line. The calculation formula is as follows:

[0065] T m =min{T m，trans T m，1，cons T m，2，cons ,…,T m，o，cons}

[0066] Among them, T m T is the final safety margin corresponding to DC tie line m. m，1，cons T m，2，cons ,…,T m，o，cons These are the cross-sectional constraints of DC tie line m relative to tie line sections 1, 2, ..., o.

[0067] In the aforementioned method for calculating the safety margin of DC tie lines based on sensitivity analysis, the following steps are taken: First, obtain the corresponding power grid forecast data, power plant operation plan data, and power grid maintenance data. Then, based on these data, obtain the cross-sectional sensitivity of each DC tie line in the power system. Next, based on any given DC tie line, obtain the remaining transmission margin of the corresponding DC tie line according to its transmission limit and future planning data. Finally, based on the cross-sectional sensitivity of each tie line, obtain the current DC tie line's constraint margin relative to other DC tie lines. The intersection of the constraint margin of each cross-section and the remaining transmission margin of the tie line is calculated to obtain the final safety margin of the DC tie line.

[0068] By comprehensively assessing the cross-sectional constraints of tie lines through cross-sectional generation and sensitivity analysis, the final safety margin analysis is achieved. This approach is highly targeted and practical, filling a gap in specialized services for the final safety margin analysis of DC tie lines in the field of planned dispatching between different power grids. It also solves problems such as low automation, long processing time, and the risk of cross-sectional exceedance in the original business model, enabling dynamic monitoring of the final safety margin of tie lines and improving the execution efficiency and safety level of power grid dispatching.

[0069] In one embodiment, such as Figure 3 As shown, based on the sensitivity of each tie line section, the constraint margin of the current DC tie line relative to the corresponding sections of other DC tie lines is obtained, including:

[0070] Step 302: Calculate the remaining adjustment margin of the DC tie line section based on the sensitivity of each tie line section and the sensitivity threshold corresponding to the tie line section sensitivity.

[0071] The sensitivity threshold can be used as a criterion for determining whether the sensitivity of the connecting line section meets the preset conditions.

[0072] Among them, the residual adjustment margin of the cross section can be the residual adjustable margin of the power flow cross section corresponding to the DC tie line during the power transmission process. In addition, in addition to the power transmission having a residual adjustable margin of the power flow cross section, the voltage and current during the transmission process also have a residual adjustable margin of the power flow cross section.

[0073] Specifically, for calculating the constraint margin of the current DC tie line relative to each cross-section of other DC tie lines, firstly, a sensitivity threshold corresponding to the tie line cross-section sensitivity is set, and then all tie line cross-sections whose absolute sensitivity value is greater than the sensitivity threshold are identified, forming a set M of tie line cross-sections of interest. staca For the set of cross-sections M of the connecting lines stacaFor each connecting line section, calculate the remaining adjustment margin of the section, expressed as:

[0074] S n，up =S n，up limit -S n，future

[0075] S n，dn =S n，future -S n，dn limit

[0076] The remaining adjustment margin of the cross-section includes the downward adjustment margin and the upward adjustment margin of the cross-section, S n，up It is an upward adjustment margin for the cross-section, S n，dn It is the downward adjustment margin of the cross-section, S n，up limit S is the upper limit of the cross-section of the connecting line n. n，dnlimit S is the lower limit of the connecting line section n. n，future It is the initial tidal current of the connecting line section.

[0077] Step 304: Based on the adjustment margin nature corresponding to the remaining adjustment margin of the cross section and the remaining adjustment margin of the cross section, obtain the restricted margin of each cross section.

[0078] Among them, the adjustment margin property can be an indicator that reflects the unique properties of the connecting line section, and is used to determine which specific type of connecting line section the connecting line section belongs to.

[0079] Specifically, for the set of connecting line sections M staca For each tie line section, the DC tie lines corresponding to the tie line sections with an absolute sensitivity value greater than the sensitivity threshold are divided into two groups. The first group of DC tie line sections corresponds to the positive sensitivity sub-tie line section set M. pos The sensitivity of the selected tie-line section is positive, and the sensitivity of the negative-sensitivity sub-tie-line section set corresponding to the second set of DC tie-line sets is negative, while the sensitivity of the positive-sensitivity sub-tie-line section set M is... pos With negative sensitivity sub-connection line section set M neg There may exist an empty set.

[0080] If the set of positive sensitivity sub-connection line sections M pos The set M is an empty set, but the set of negative sensitivity sub-connection line sections. neg If it is not an empty set, then adjust the cross-section downwards by a margin S. n，dn Combined with the set of negative sensitivity sub-connection line sections M neg The corresponding tie-line remaining transmission margin T m，trans Calculate the cross-sectional constraint margin of each tie line in the set, considering the mutual sensitivity e between the tie line sections of each DC tie line:

[0081] T m，n，cons =T m，trans ·S n，dn / ∑(e m，n ·T m，trans )

[0082] Among them, T m，n，cons It is the sectional margin of DC tie line m relative to tie line section n, e m，n It is the mutual sensitivity of DC tie line m to tie line section n.

[0083] If the set of positive sensitivity sub-connection line sections M pos Not an empty set, but a set of negatively sensitive sub-connection line sections M neg If it is an empty set, then adjust the cross-section upwards by a margin S. n，up Combined with the set of positive sensitivity sub-connection line sections M pos The corresponding tie-line remaining transmission margin T m，trans Calculate the cross-sectional constraint margin of each tie line in the set, considering the mutual sensitivity e between the tie line sections of each DC tie line:

[0084] T m，n，cons =T m，trans ·S n，up / ∑(e m，n ·T m，trans )

[0085] Among them, T m，n，cons It is the sectional margin of DC tie line m relative to tie line section n, e m，n It is the mutual sensitivity of DC tie line m to tie line section n.

[0086] If the set of positive sensitivity sub-connection line sections M pos and the set of negative sensitivity sub-connection line sections M neg If none of them are empty sets, then first fix the future planning data of each DC tie line in the set of positive sensitivity sub-tie line sections, and then execute "If the set of positive sensitivity sub-tie line sections M..." pos The set M is an empty set, but the set of negative sensitivity sub-connection line sections. neg If it is not an empty set, then adjust the cross-section downwards by a margin S. n，dn Combined with the set of negative sensitivity sub-connection line sections M neg The corresponding tie-line remaining transmission margin T m，trans Calculate the cross-sectional constraint margin of each tie line in the set, considering the mutual sensitivity e between the tie line sections of each DC tie line:

[0087] T m，n，cons =T m，trans ·S n，dn / ∑(e m，n ·Tm，trans )

[0088] Among them, T m，n，cons It is the sectional margin of DC tie line m relative to tie line section n, e m，n "It is the mutual sensitivity of DC tie line m to tie line section n".

[0089] Additionally, the future planning data for each DC tie line in the set of negative sensitivity sub-tie line sections is fixed, and then the process "If the set of positive sensitivity sub-tie line sections M" is executed. pos Not an empty set, but a set of negatively sensitive sub-connection line sections M neg If it is an empty set, then adjust the cross-section upwards by a margin S. n，up Combined with the set of positive sensitivity sub-connection line sections M pos The corresponding tie-line remaining transmission margin T m，trans Calculate the cross-sectional constraint margin of each tie line in the set, considering the mutual sensitivity e between the tie line sections of each DC tie line:

[0090] T m，n，cons =T m，trans ·S n，up / ∑(e m，n ·T m，trans )

[0091] Among them, T m，n，cons It is the cross-sectional margin of DC tie line m relative to tie line section n, e m，n "It is the mutual sensitivity of DC tie line m to tie line section n".

[0092] In this embodiment, the remaining adjustment margin of the cross section can be obtained through one of the conditions of sensitivity threshold. By combining the adjustment margin properties for analysis, the calculation of the cross section constraint margin under different properties can be satisfied, so as to achieve different cross section constraint margins for different situations and improve the accuracy of the final safety margin calculation of DC tie lines.

[0093] In one embodiment, such as Figure 4 As shown, based on the sensitivity of each tie line section and the corresponding sensitivity threshold, the remaining adjustment margin of the corresponding DC tie line section is calculated, including:

[0094] Step 402: Obtain the sensitivity threshold corresponding to the sensitivity of each tie line section, and determine the tie line section set corresponding to each DC tie line based on each sensitivity threshold.

[0095] The set of connecting line cross-sections can be a combination of connecting line cross-sections that meet the sensitivity threshold.

[0096] Specifically, for calculating the constraint margin of the current DC tie line relative to each cross-section of other DC tie lines, firstly, a sensitivity threshold corresponding to the tie line cross-section sensitivity is set, and then all tie line cross-sections whose absolute sensitivity value is greater than the sensitivity threshold are identified, forming a set M of tie line cross-sections of interest. staca .

[0097] Step 404: Based on any DC tie line, determine the remaining adjustment margin of the corresponding DC tie line section according to the upper limit and lower limit of the tie line section.

[0098] The upper limit of the tie line cross section can be the upper limit value corresponding to any tie line cross section, which can be the upper limit value of power, current and voltage.

[0099] The lower limit of the tie line section can be the lower limit value corresponding to any tie line section, and can be the lower limit value of power, current and voltage.

[0100] Specifically, for the set of connecting line sections M staca For each connecting line section, calculate the remaining adjustment margin of the section, expressed as:

[0101] S n，up =S n，up limit -S n，future

[0102] S n，dn =S n，future -S n，dn limit

[0103] The remaining adjustment margin of the cross-section includes the downward adjustment margin and the upward adjustment margin of the cross-section, S n，up It is an upward adjustment margin for the cross-section, S n，dn It is the downward adjustment margin of the cross-section, S n，up limit S is the upper limit of the cross-section of the connecting line n. n，dnlimit S is the lower limit of the connecting line section n. n，future It is the initial tidal current of the connecting line section.

[0104] In this embodiment, the remaining adjustment margin of the cross-section is determined by the upper limit and lower limit of the cross-section of the connecting line. The results can be obtained quantitatively from the specific detection parameters, avoiding the deviation of the remaining adjustment margin of the cross-section due to subjective observation.

[0105] In one embodiment, such as Figure 5 As shown, based on the adjustment margin nature corresponding to the remaining adjustment margin of the cross-section and the remaining adjustment margin of the cross-section, the constraint margin of each cross-section is obtained, including:

[0106] Step 502: Based on any one of the connecting line cross-sections in the set of connecting line cross-sections, classify the set of connecting line cross-sections according to the type of connecting line cross-section to obtain the set of positive sensitivity sub-connecting line cross-sections and the set of negative sensitivity sub-connecting line cross-sections corresponding to the set of connecting line cross-sections.

[0107] Among them, the set of positive sensitivity sub-connecting line sections can be the set of connecting line sections whose absolute sensitivity value is greater than the sensitivity threshold and which exhibit positive sensitivity.

[0108] Among them, the set of negative sensitivity sub-connecting line sections can be the set of connecting line sections whose absolute sensitivity value is greater than the sensitivity threshold and which exhibit negative sensitivity.

[0109] Specifically, for the set of connecting line sections M staca For each tie line section, the DC tie lines corresponding to the tie line sections with an absolute sensitivity value greater than the sensitivity threshold are divided into two groups. The first group of DC tie line sections corresponds to the positive sensitivity sub-tie line section set M. pos The sensitivity of the selected tie-line section is positive, and the sensitivity of the negative-sensitivity sub-tie-line section set corresponding to the second set of DC tie-line sets is negative, while the sensitivity of the positive-sensitivity sub-tie-line section set M is... pos With negative sensitivity sub-connection line section set M neg There may exist an empty set.

[0110] Step 504: When the set of positive sensitivity sub-tether sections is empty, the constraint margin of each section corresponding to the set of positive sensitivity sub-tether sections is obtained based on the downward adjustment margin of the section, the remaining transmission margin of the tie line corresponding to the set of negative sensitivity sub-tether sections, and the mutual sensitivity between the tie line sections of each DC tie line.

[0111] The downward adjustment margin of the cross-section can be defined as the extent to which the power, current, and voltage values ​​corresponding to the cross-section of the tie line can be adjusted downwards.

[0112] Mutual sensitivity can be the sensitivity difference between the cross sections of different DC tie lines.

[0113] Specifically, if the set of positive sensitivity sub-connection line sections M pos The set M is an empty set, but the set of negative sensitivity sub-connection line sections. neg If it is not an empty set, then adjust the cross-section downwards by a margin S. n，dn Combined with the set of negative sensitivity sub-connection line sections M neg The corresponding tie-line remaining transmission margin T m，transCalculate the cross-sectional constraint margin of each tie line in the set, considering the mutual sensitivity e between the tie line sections of each DC tie line:

[0114] T m，n，cons =T m，trans ·S n，dn / ∑(e m，n ·T m，trans )

[0115] Among them, T m，n，cons It is the sectional margin of DC tie line m relative to tie line section n, e m，n It is the mutual sensitivity of DC tie line m to tie line section n.

[0116] Step 506: When the set of negative sensitivity sub-tether sections is empty, the constraint margin of each section corresponding to the set of negative sensitivity sub-tether sections is obtained based on the section upward adjustment margin, the remaining transmission margin of the tie line corresponding to the set of positive sensitivity sub-tether sections, and the mutual sensitivity between the tie line sections of each DC tie line.

[0117] The upward adjustment margin of the cross-section can be the degree to which the power, current and voltage values ​​corresponding to the cross-section of the tie line can be adjusted upward.

[0118] Specifically, if the set of positive sensitivity sub-connection line sections M pos Not an empty set, but a set of negatively sensitive sub-connection line sections M neg If it is an empty set, then adjust the cross-section upwards by a margin S. n，up Combined with the set of positive sensitivity sub-connection line sections M pos The corresponding tie-line remaining transmission margin T m，trans Calculate the cross-sectional constraint margin of each tie line in the set, considering the mutual sensitivity e between the tie line sections of each DC tie line:

[0119] T m，n，cons =T m，trans ·S n，up / ∑(e m，n ·T m，trans )

[0120] Among them, T m，n，cons It is the sectional margin of DC tie line m relative to tie line section n, e m，n It is the mutual sensitivity of DC tie line m to tie line section n.

[0121] Step 508: When neither the set of positive sensitivity sub-tie line sections nor the set of negative sensitivity sub-tie line sections is empty, based on the future planning data of each DC tie line in the set of positive sensitivity sub-tie line sections, and according to the downward adjustment margin of the section, the remaining transmission margin of the tie line corresponding to the set of negative sensitivity sub-tie line sections, and the mutual sensitivity between the tie line sections of each DC tie line, the constraint margin of each section corresponding to the negative sensitivity sub-tie line section is obtained.

[0122] Specifically, if the set of positive sensitivity sub-connection line sections M pos and the set of negative sensitivity sub-connection line sections M neg If none of them are empty sets, then first fix the future planning data of each DC tie line in the set of positive sensitivity sub-tie line sections, and then execute "If the set of positive sensitivity sub-tie line sections M..." pos The set M is an empty set, but the set of negative sensitivity sub-connection line sections. neg If it is not an empty set, then adjust the cross-section downwards by a margin S. n，dn Combined with the set of negative sensitivity sub-connection line sections M neg The corresponding tie-line remaining transmission margin T m，trans Calculate the cross-sectional constraint margin of each tie line in the set, considering the mutual sensitivity e between the tie line sections of each DC tie line:

[0123] T m，n，cons =T m，trans ·S n，dn / ∑(e m，n ·T m，trans )

[0124] Among them, T m，n，cons It is the sectional margin of DC tie line m relative to tie line section n, e m，n "It is the mutual sensitivity of DC tie line m to tie line section n".

[0125] Step 510: Based on the future planning data of each DC tie line in the negative sensitivity sub-tie line section set, and according to the section upward adjustment margin, the remaining transmission margin of the tie line corresponding to the positive sensitivity sub-tie line section set, and the mutual sensitivity between the tie line sections of each DC tie line, the constraint margin of each section corresponding to the positive sensitivity sub-tie line section set is obtained.

[0126] Specifically, the future planning data of each DC tie line in the set of negative sensitivity sub-tie line sections is fixed, and then the process "If the set of positive sensitivity sub-tie line sections M" is executed. pos Not an empty set, but a set of negatively sensitive sub-connection line sections M neg If it is an empty set, then adjust the cross-section upwards by a margin S. n，up Combined with the set of positive sensitivity sub-connection line sections M pos The corresponding tie-line remaining transmission margin Tm，trans Calculate the cross-sectional constraint margin of each tie line in the set, considering the mutual sensitivity e between the tie line sections of each DC tie line:

[0127] T m，n，cons =T m，trans ·S n，up / ∑(e m，n ·T m，trans )

[0128] Among them, T m，n，cons It is the cross-sectional margin of DC tie line m relative to tie line section n, e m，n "It is the mutual sensitivity of DC tie line m to tie line section n".

[0129] In this embodiment, by analyzing different combinations of the positive sensitivity sub-connector section set and the negative sensitivity sub-connector section set, the constraint margin of each section is obtained. Different calculation methods can be adopted based on different connecting line section conditions to reduce the increase in error caused by using a non-refined calculation method.

[0130] In one embodiment, such as Figure 6 As shown, based on power grid forecast data, power plant operation plan data, and power grid maintenance data, the sensitivity of each DC tie line section in the power system is obtained, including:

[0131] Step 602: Perform AC power flow calculation on the ultra-short-term system load forecast data and ultra-short-term bus load forecast data to obtain the initial power flow of each DC tie line section.

[0132] Among them, the ultra-short-term system load forecast data can be obtained by predicting the system load for the next 5 minutes, 10 minutes, or 15 minutes based on the real-time system load, combined with the characteristics of date types such as weekdays and rest days and historical system loads.

[0133] Among them, the ultra-short-term bus load forecast data can be obtained by predicting the bus load for the next 5 minutes, 10 minutes, or 15 minutes based on the real-time bus load, combined with the characteristics of date types such as weekdays and rest days and historical bus loads.

[0134] The initial power flow of the tie line section can be the result obtained by using the ultra-short-term system load forecast data and ultra-short-term bus load forecast data as parameters and calculating the AC power flow.

[0135] Specifically, AC power flow calculations are performed using ultra-short-term system load forecast data and ultra-short-term bus load forecast data from the power grid forecasting data. This yields the initial power flow at each DC tie-line cross-section of the power system. The AC power flow calculations require the use of the nodal voltage method, the Newton-Raphson method, or the PQ decoupling method, with the nodal admittance matrix Y serving as the mathematical model of the power network. Nodal voltage U i and node injection current I i This is related to the node voltage equations. Under known operating conditions, the power injected into the nodes is not the node current, but rather the load and generator power, and this power generally does not change with node voltage variations. The relationship between the injected power and injected current at each node is as follows:

[0136] S i =P i +jQ i =U i I i

[0137] In the formula, P i and Q i Let P be the active power and reactive power injected into the network by node i, respectively. When i is a generator node, P... i >0; when i is a load node, P i <0; when i is a passive node P i =0, Q i =0;U i and I i These are the node voltage phasors U. i and node injection current phasor I i The conjugate of . There are n nonlinear complex equations, which are the basic equations for power flow calculation. It can establish 2n real-form power equations in either rectangular or polar coordinates.

[0138] Given the network wiring and branch parameters, the node admittance matrix Y in AC power flow calculations can be derived. The injected active power P is the variable representing the system's operating state in the AC power flow equations. i Reactive power Q i and node voltage phasor U i (Amplitude Ui and phase angle δ) i A power grid with n nodes has 4n variables, but only 2n power equations; therefore, 2n operating state variables must be given. Depending on the given node variables, there are three types of nodes.

[0139] PU node: (Voltage control bus) Active power P i and voltage amplitude U iGiven. This type of node is equivalent to a generator bus node, or a substation bus equipped with a synchronous condenser or static compensator. The active power P injected into the PQ node is... i and reactive power Q i It is a given value. It corresponds to a load node in a real power system, or a generator bus with given active and reactive power. A slack node: used to balance the power of the entire power grid. The voltage amplitude U of a slack node. i and phase angle δ i It is given, and its phase angle is usually used as the reference point, that is, its voltage phase angle is taken as zero. An independent power grid has only one slack node. The corresponding power system can be obtained.

[0140] Step 604: Based on the initial power flow of the tie line section, the power plant operation plan data, and the power grid maintenance data, obtain the tie line section sensitivity corresponding to each DC tie line in the power system.

[0141] Specifically, based on the initial power flow of the tie line section, the future power plant plan data generated by each electrical island in the interconnected power grid in the power plant operation plan data, and the power grid maintenance data, the ratio of the impact of the power increase or decrease of the channel corresponding to the DC tie line on the section is calculated, and the tie line section sensitivity corresponding to each DC tie line in the power system is obtained.

[0142] In this embodiment, by using AC power flow calculation to calculate the power plant operation plan data, the cross-sectional data of the DC tie line can be accurately obtained, thereby improving the accuracy of subsequent margin calculations for the DC tie line.

[0143] In one embodiment, such as Figure 7 As shown, the intersection of the constraint margin of each section and the remaining transmission margin of the tie line is calculated to obtain the final safety margin corresponding to the DC tie line, including:

[0144] Step 702: Calculate the intersection of all cross-sectional constraint margins to obtain the final constraint margin of the DC tie line.

[0145] The ultimate constraint margin of the tie line can be the maximum limit that the power, voltage and current of the DC tie line can be adjusted after calculation, but it does not mean that the power system can be guaranteed to be safe within this limit.

[0146] Specifically, the final constraint margin of the DC tie line can be obtained by calculating the intersection of the constraint margins of each section. The calculation formula is as follows:

[0147] T max =min{T m，1，cons T m，2，cons ,…,T m，o，cons}

[0148] T max T is the final constraint margin of the DC tie line m. m，1，cons， T m，2，cons， …, T m，o，cons These are the cross-sectional constraints of DC tie line m relative to tie line sections 1, 2, ..., o.

[0149] Step 704: Calculate the intersection between the final confined margin of the tie line and the remaining transmission margin of the tie line to obtain the final safety margin corresponding to the DC tie line.

[0150] Specifically, the final safety margin of the DC tie line can be obtained by calculating the intersection between the final constraint margin and the remaining transmission margin of the tie line, as shown in the following formula:

[0151] T m =min{T m，trans T max}

[0152] Among them, T m T is the final safety margin corresponding to DC tie line m. max T is the final constraint margin of the DC tie line m. m，trans It represents the remaining transmission margin of the tie line.

[0153] In this embodiment, by calculating the intersection between the limited margins of each section and then calculating the intersection between the limited margin and the remaining transmission margin of the tie line, it is possible to ensure that all data in the DC tie line are within the different margins of the sections, avoiding overflow, and making the final safety margin the safest range value of the power system, thereby improving the safety of the power system.

[0154] It should be understood that although the steps in the flowcharts of the above embodiments are shown sequentially according to the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless explicitly stated herein, there is no strict order restriction on the execution of these steps, and they can be executed in other orders. Moreover, at least some steps in the flowcharts of the above embodiments may include multiple steps or multiple stages. These steps or stages are not necessarily completed at the same time, but can be executed at different times. The execution order of these steps or stages is not necessarily sequential, but can be performed alternately or in turn with other steps or at least some of the steps or stages of other steps.

[0155] Based on the same inventive concept, this application also provides a DC tie-line safety margin calculation device for implementing the aforementioned DC tie-line safety margin calculation method based on sensitivity analysis. The solution provided by this device is similar to the implementation described in the above method. Therefore, the specific limitations of one or more embodiments of the DC tie-line safety margin calculation device based on sensitivity analysis provided below can be found in the above-described limitations of the DC tie-line safety margin calculation method based on sensitivity analysis, and will not be repeated here.

[0156] In one embodiment, such as Figure 8 As shown, a DC tie-line safety margin calculation device based on sensitivity analysis is provided, including: a tie-line cross-sectional sensitivity acquisition module 802, a tie-line intermediate margin calculation module 804, and a final safety margin acquisition module 806, wherein:

[0157] The tie-line section sensitivity acquisition module 802 is used to acquire the power grid forecast data, power plant operation plan data and power grid maintenance data corresponding to the power system, and obtain the tie-line section sensitivity corresponding to each DC tie-line in the power system based on the power grid forecast data, power plant operation plan data and power grid maintenance data.

[0158] The intermediate margin calculation module 804 is used to obtain the remaining transmission margin of the DC tie line based on any DC tie line, according to the transmission limit of the DC tie line and the future planning data of the DC tie line; and to obtain the current DC tie line's limited margin relative to the other DC tie lines based on the sensitivity of each tie line section.

[0159] The final safety margin module 806 is used to calculate the intersection between the limited margin of each section and the remaining transmission margin of the tie line to obtain the final safety margin corresponding to the DC tie line.

[0160] In one embodiment, the tie line intermediate margin calculation module 804 is further configured to calculate the residual adjustment margin of the DC tie line section based on the sensitivity of each tie line section and the sensitivity threshold corresponding to the tie line section sensitivity; and to obtain the restricted margin of each section based on the adjustment margin nature corresponding to the residual adjustment margin of the section and the residual adjustment margin of the section.

[0161] In one embodiment, the tie-line intermediate margin calculation module 804 is further configured to obtain the sensitivity threshold corresponding to the sensitivity of each tie-line section, and determine the tie-line section set corresponding to each DC tie-line based on each sensitivity threshold; the tie-line section set includes the upper limit and lower limit of the tie-line section corresponding to each DC tie-line; based on any DC tie-line, the remaining adjustment margin of the section corresponding to the DC tie-line is determined according to the upper limit and lower limit of the tie-line section; the remaining adjustment margin of the section includes the downward adjustment margin and the upward adjustment margin.

[0162] In one embodiment, the tie-line intermediate margin calculation module 804 is further configured to classify the tie-line cross-section set according to the type of tie-line cross-section based on any tie-line cross-section in the tie-line cross-section set, to obtain a set of positive sensitivity sub-tie-line cross-sections and a set of negative sensitivity sub-tie-line cross-sections corresponding to the tie-line cross-section set; when the set of positive sensitivity sub-tie-line cross-sections is empty, the constraint margin of each cross-section corresponding to the positive sensitivity sub-tie-line cross-section set is obtained based on the cross-section downward adjustment margin, the tie-line remaining transmission margin corresponding to the negative sensitivity sub-tie-line cross-section set, and the mutual sensitivity between the tie-line cross-sections of each DC tie-line; when the set of negative sensitivity sub-tie-line cross-sections is empty, the constraint margin of each cross-section corresponding to the cross-section upward adjustment margin, the tie-line remaining transmission margin corresponding to the positive sensitivity sub-tie-line cross-section set, and the mutual sensitivity between the tie-line cross-sections of each DC tie-line is obtained based on the cross-section upward adjustment margin, the tie-line remaining transmission margin corresponding to the positive sensitivity sub-tie-line cross-section set, and the mutual sensitivity between the tie-line cross-sections of each DC tie-line. Sensitivity is used to obtain the constraint margin of each section corresponding to the set of negative sensitivity sub-tether sections; when neither the set of positive sensitivity sub-tether sections nor the set of negative sensitivity sub-tether sections is empty, based on the future planning data of each DC tie line in the set of positive sensitivity sub-tether sections, according to the downward adjustment margin of the section, the remaining transmission margin of the tie line corresponding to the set of negative sensitivity sub-tether sections, and the mutual sensitivity between the tie line sections of each DC tie line, the constraint margin of each section corresponding to the set of negative sensitivity sub-tether sections is obtained; and based on the future planning data of each DC tie line in the set of negative sensitivity sub-tether sections, according to the upward adjustment margin of the section, the remaining transmission margin of the tie line corresponding to the set of positive sensitivity sub-tether sections, and the mutual sensitivity between the tie line sections of each DC tie line, the constraint margin of each section corresponding to the set of positive sensitivity sub-tether sections is obtained.

[0163] In one embodiment, the tie-line section sensitivity obtaining module 802 is also used to perform AC power flow calculation on the ultra-short-term system load forecast data and the ultra-short-term bus load forecast data to obtain the initial power flow of each tie-line section corresponding to each DC tie-line; and to obtain the tie-line section sensitivity of each DC tie-line in the power system based on the initial power flow of the tie-line section, the power plant operation plan data and the power grid maintenance data.

[0164] In one embodiment, the final safety margin module 806 is further used to calculate the intersection of all cross-sectional constraint margins to obtain the final constraint margin of the DC tie line; and to calculate the intersection of the final constraint margin of the tie line and the remaining transmission margin of the tie line to obtain the final safety margin of the DC tie line.

[0165] The modules in the aforementioned DC tie-line safety margin calculation device based on sensitivity analysis can be implemented entirely or partially through software, hardware, or a combination thereof. These modules can be embedded in or independent of the processor in a computer device, or stored in the memory of a computer device as software, so that the processor can call and execute the corresponding operations of each module.

[0166] In one embodiment, a computer device is provided, which may be a server, and its internal structure diagram may be as follows: Figure 9 As shown, the computer device includes a processor, memory, and a network interface connected via a system bus. The processor provides computing and control capabilities. The memory includes non-volatile storage media and internal memory. The non-volatile storage media stores the operating system, computer programs, and a database. The internal memory provides an environment for the operation of the operating system and computer programs in the non-volatile storage media. The database stores server data. The network interface communicates with external terminals via a network connection. When executed by the processor, the computer program implements a method for calculating the safety margin of a DC tie-line based on sensitivity analysis.

[0167] Those skilled in the art will understand that Figure 9 The structure shown is merely a block diagram of a portion of the structure related to the present application and does not constitute a limitation on the computer device to which the present application is applied. Specific computer devices may include more or fewer components than those shown in the figure, or combine certain components, or have different component arrangements.

[0168] In one embodiment, a computer device is also provided, including a memory and a processor, wherein the memory stores a computer program, and the processor executes the computer program to implement the steps in the above method embodiments.

[0169] In one embodiment, a computer-readable storage medium is provided storing a computer program that, when executed by a processor, implements the steps in the above method embodiments.

[0170] In one embodiment, a computer program product or computer program is provided, the computer program product or computer program including computer instructions stored in a computer-readable storage medium. A processor of a computer device reads the computer instructions from the computer-readable storage medium, and executes the computer instructions, causing the computer device to perform the steps in the above method embodiments.

[0171] It should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for analysis, data stored, data displayed, etc.) involved in this application are all information and data authorized by the user or fully authorized by all parties.

[0172] Those skilled in the art will understand that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer-readable storage medium, and when executed, it can include the processes of the embodiments of the above methods. Any references to memory, databases, or other media used in the embodiments provided in this application can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetic random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. By way of illustration and not limitation, RAM can take many forms, such as Static Random Access Memory (SRAM) or Dynamic Random Access Memory (DRAM). The databases involved in the embodiments provided in this application may include at least one type of relational database and non-relational database. Non-relational databases may include, but are not limited to, blockchain-based distributed databases. The processors involved in the embodiments provided in this application may be general-purpose processors, central processing units, graphics processing units, digital signal processors, programmable logic devices, quantum computing-based data processing logic devices, etc., and are not limited to these.

[0173] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0174] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of this patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this application should be determined by the appended claims.

Claims

1. A method for calculating the safety margin of DC tie lines based on sensitivity analysis, characterized in that, The method includes: Acquire grid forecast data, power plant operation plan data, and grid maintenance data corresponding to the power system. The grid forecast data includes ultra-short-term system load forecast data and ultra-short-term bus load forecast data. Based on the grid forecast data, the power plant operation plan data, and the grid maintenance data, obtain the sensitivity of each DC tie line section in the power system. This includes: performing AC power flow calculations on the ultra-short-term system load forecast data and the ultra-short-term bus load forecast data to obtain the initial power flow of each DC tie line section; and obtaining the sensitivity of each DC tie line section in the power system based on the initial power flow of the tie line sections, the power plant operation plan data, and the grid maintenance data. Based on any one of the DC tie lines, according to the transmission limit and future planning data of the DC tie line, the remaining transmission margin of the DC tie line is obtained; and according to the sensitivity of each tie line section, the current DC tie line relative to the section constraints of the other DC tie lines is obtained, including: calculating the section remaining adjustment margin of the DC tie line based on the section sensitivity of each tie line and the sensitivity threshold corresponding to the section sensitivity; and obtaining the section constraint margin based on the adjustment margin nature corresponding to the section remaining adjustment margin and the section remaining adjustment margin. The intersection of the constraint margin of each section and the remaining transmission margin of the tie line is calculated to obtain the final safety margin corresponding to the DC tie line.

2. The method according to claim 1, characterized in that, The step of calculating the remaining adjustment margin of the DC tie line section based on the sensitivity of each tie line section and the sensitivity threshold corresponding to the sensitivity of the tie line section includes: Obtain the sensitivity threshold corresponding to the sensitivity of each of the aforementioned tie line sections, and determine the tie line section set corresponding to each of the aforementioned DC tie lines based on the sensitivity thresholds; the tie line section set includes the upper limit and lower limit of the tie line section corresponding to each of the aforementioned DC tie lines. Based on any one of the DC tie lines, the remaining adjustment margin of the cross-section corresponding to the DC tie line is determined according to the upper limit and the lower limit of the cross-section of the tie line; the remaining adjustment margin of the cross-section includes the downward adjustment margin and the upward adjustment margin.

3. The method according to claim 2, characterized in that, The step of obtaining the constraint margin of each section based on the adjustment margin nature corresponding to the remaining adjustment margin of the section and the remaining adjustment margin of the section includes: Based on any one of the connecting line sections in the set of connecting line sections, the set of connecting line sections is classified according to the type of the connecting line section to obtain the set of positive sensitivity sub-connecting line sections and the set of negative sensitivity sub-connecting line sections corresponding to the set of connecting line sections. When the set of positive sensitivity sub-tether sections is empty, the constraint margin of each section corresponding to the set of positive sensitivity sub-tether sections is obtained based on the downward adjustment margin of the section, the remaining transmission margin of the tie line corresponding to the set of negative sensitivity sub-tether sections, and the mutual sensitivity between the tie line sections of each DC tie line. When the set of negative sensitivity sub-tether sections is empty, the constraint margin of each section corresponding to the set of negative sensitivity sub-tether sections is obtained based on the upward adjustment margin of the section, the remaining transmission margin of the tie line corresponding to the set of positive sensitivity sub-tether sections, and the mutual sensitivity between the tie line sections of each DC tie line. When neither the set of positive sensitivity sub-tether sections nor the set of negative sensitivity sub-tether sections is empty, based on the future planning data of each DC tie line in the set of positive sensitivity sub-tether sections, and according to the downward adjustment margin of the section, the remaining transmission margin of the tie line corresponding to the set of negative sensitivity sub-tether sections, and the mutual sensitivity between the tie line sections of each DC tie line, the constraint margin of each section corresponding to the set of negative sensitivity sub-tether sections is obtained. as well as, Based on the future planning data of each DC tie line in the negative sensitivity sub-tie line section set, and according to the upward adjustment margin of the section, the remaining transmission margin of the tie line corresponding to the positive sensitivity sub-tie line section set, and the mutual sensitivity between the tie line sections of each DC tie line, the constraint margin of each section corresponding to the positive sensitivity sub-tie line section set is obtained.

4. The method according to claim 1, characterized in that, The calculation of the intersection between the constraint margin of each cross section and the remaining transmission margin of the tie line to obtain the final safety margin corresponding to the DC tie line includes: Calculate the intersection of all the cross-sectional constraint margins to obtain the final constraint margin of the DC tie line; The final safety margin of the DC tie line is obtained by calculating the intersection between the final constraint margin and the remaining transmission margin of the tie line.

5. A device for calculating the safety margin of a DC tie line based on sensitivity analysis, characterized in that, The device includes: The tie-line section sensitivity acquisition module is used to acquire grid forecast data, power plant operation plan data, and grid maintenance data corresponding to the power system. The grid forecast data includes ultra-short-term system load forecast data and ultra-short-term bus load forecast data. Based on the grid forecast data, the power plant operation plan data, and the grid maintenance data, the module obtains the tie-line section sensitivity corresponding to each DC tie-line in the power system. This includes: performing AC power flow calculations on the ultra-short-term system load forecast data and the ultra-short-term bus load forecast data to obtain the initial power flow of each tie-line section corresponding to each DC tie-line; and obtaining the tie-line section sensitivity corresponding to each DC tie-line in the power system based on the initial power flow of the tie-line section, the power plant operation plan data, and the grid maintenance data. The tie-line intermediate margin calculation module is used to obtain the remaining transmission margin of any DC tie-line based on the transmission limit and future planning data of the DC tie-line; and to obtain the current DC tie-line's cross-sectional constraint margin relative to other DC tie-lines based on the sensitivity of each tie-line cross-section, including: calculating the remaining adjustment margin of the cross-section corresponding to the DC tie-line based on the sensitivity of each tie-line cross-section and the sensitivity threshold corresponding to the cross-section sensitivity; and obtaining the constraint margin of each cross-section based on the adjustment margin nature corresponding to the remaining adjustment margin and the remaining adjustment margin of the cross-section. The final safety margin acquisition module is used to calculate the intersection between the limited margin of each section and the remaining transmission margin of the tie line to obtain the final safety margin corresponding to the DC tie line.

6. A computer device comprising a memory and a processor, wherein the memory stores a computer program, characterized in that, When the processor executes the computer program, it implements the steps of the method according to any one of claims 1 to 4.

7. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by a processor, it implements the steps of the method according to any one of claims 1 to 4.

8. A computer program product, comprising a computer program, characterized in that, When the computer program is executed by a processor, it implements the steps of the method according to any one of claims 1 to 4.

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