Method and system for calculating dynamic power transmission limit of multi-station new energy delivery

Abstract

The application provides a kind of multi-station new energy export dynamic power transmission limit calculation method and system, the method includes based on the parameter value of each kind of node of multi-station new energy sending system constructs low-dimensional voltage stability analysis model, and determines the upper boundary of dynamic power transmission limit under the first power change speed of new energy export;Again, the low-dimensional voltage stability analysis model is equivalent to the Thevenin value, determine the lower boundary of dynamic power transmission limit under the second power change speed of new energy export, and according to the upper boundary and lower boundary, and its corresponding new energy first, second power change speed determines the expression for calculating the dynamic power transmission limit of multi-station new energy export. The method and system realize the dynamic analysis of new energy export power transmission limit, can effectively improve the ability of power grid to resist risk, and fully tap the transmission potential of system, guide new energy station planning reasonable power generation plan, improve the utilization rate of new energy.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of power system safety and stability analysis, and more particularly, to a multi-station new energy sending dynamic power transmission limit calculation method and system. BACKGROUND

[0002] With the development of new energy technology, the proportion of wind power, photovoltaic and other new energy power generation in the power system is increasing. Compared with conventional power sources, the output of new energy has intermittency and volatility, and its reactive power support capacity and regulation capacity are relatively weak, which has caused significant changes in the dynamic characteristics of the power grid. Under this background, the voltage stability problem is increasingly prominent, and has become a key factor restricting the safe and efficient operation of the power system.

[0003] The power transmission limit is a key indicator for measuring the voltage stability level of the system, which is affected by many factors such as new energy output characteristics, system structure, load characteristics, etc. With the expansion of the multi-station new energy grid-connected scale, the power system operation faces more complex challenges, and it is urgent to conduct in-depth research on the new energy sending power transmission limit to ensure the safe and stable operation of the system. SUMMARY

[0004] In order to solve the technical problem in the prior art that the expansion of the multi-station new energy grid-connected scale of the power system causes changes in the dynamic characteristics of the power grid, the voltage stability problem is increasingly prominent, but the new energy sending power transmission limit lacks a determination method, the present application provides a multi-station new energy sending dynamic power transmission limit calculation method and system.

[0005] According to an aspect of the present application, a multi-station new energy sending dynamic power transmission limit calculation method is provided, which comprises:

[0006] According to the self-inductance matrix, voltage column vector and current column vector of the generator node, load node, new energy node and other nodes contained in the multi-station new energy sending system, and the mutual inductance between the nodes, a first network matrix of the multi-station new energy sending system is established;

[0007] The other nodes in the first network matrix are subjected to Gaussian elimination to establish a second network matrix of a low-dimensional new energy sending system;

[0008] The generator nodes, load nodes and new energy nodes in the second network matrix are respectively aggregated and equivalent, and a matrix transformation dimension reduction method of voltage mean and current summation is used to determine a low-dimensional voltage stability analysis model of the multi-station new energy sending system and a first model parameter value of the low-dimensional voltage stability analysis model, wherein the low-dimensional voltage stability analysis model includes the system side, load side and new energy side after the aggregation of the generator nodes, load nodes and new energy nodes, respectively.

[0009] determine an upper boundary of the dynamic power transmission limit of the new energy outflow of the multi-station under the new energy first power change speed according to the first model parameter value;

[0010] According to the low-dimensional voltage stability analysis model, the load side is equivalent to an equivalent resistor, and the system side and the load side are Thevenin equivalent from the new energy side. After generating the Thevenin equivalent analysis model, the second model parameter value of the Thevenin equivalent analysis model is determined according to the first model parameter value.

[0011] determine a lower boundary of the dynamic power transmission limit of the new energy outflow of the multi-station under the new energy second power change speed according to the second model parameter value, wherein the new energy second power change speed is greater than the new energy first power change speed.

[0012] Based on the dynamic power transmission limit model of the new energy outflow of the multi-station, according to the upper boundary and the lower boundary, and the corresponding new energy first and second power change speeds, an expression for calculating the dynamic power transmission limit of the new energy outflow of the multi-station in the multi-station new energy sending system is determined.

[0013] According to another aspect of the present application, the present application provides a system for calculating the dynamic power transmission limit of the new energy outflow of the multi-station, the system comprising:

[0014] A first matrix module is used to establish a first network matrix of the multi-station new energy sending system according to the self-inductance matrix, the voltage column vector and the current column vector of the generator node, the load node, the new energy node and other nodes contained in the multi-station new energy sending system, and the mutual inductance between the nodes.

[0015] A second matrix module is used to perform Gaussian elimination on the other nodes in the first network matrix to establish a second network matrix of the low-dimensional new energy sending system.

[0016] A first model module is used to respectively aggregate and equivalent the generator node, the load node and the new energy node in the second network matrix, and determine a low-dimensional voltage stability analysis model of the multi-station new energy sending system and a first model parameter value of the low-dimensional voltage stability analysis model by using a matrix transformation dimension reduction method of voltage mean value and current summation. The low-dimensional voltage stability analysis model includes the system side, the load side and the new energy side after aggregating the generator node, the load node and the new energy node respectively.

[0017] A first boundary module is used to determine an upper boundary of the dynamic power transmission limit of the new energy outflow of the multi-station under the new energy first power change speed according to the first model parameter value.

[0018] a second model module, configured to, for the low-dimensional voltage stability analysis model, equivalent the load side to an equivalent resistance, and perform Thevenin equivalent on the system side and the load side from the new energy side, to generate a Thevenin equivalent analysis model, and determine second model parameter values of the Thevenin equivalent analysis model according to the first model parameter values;

[0019] a second boundary module, configured to calculate a lower boundary of the dynamic power transmission limit of the new energy out-of-station of the multiple stations at a second power change speed of the new energy according to the second model parameter values, wherein the second power change speed of the new energy is greater than the first power change speed of the new energy;

[0020] a result output module, configured to determine an expression for calculating the dynamic power transmission limit of the new energy out-of-station of the multiple stations in the new energy sending-out system according to the upper boundary and the lower boundary and the corresponding first and second power change speeds of the new energy based on the dynamic power transmission limit model of the new energy out-of-station of the multiple stations.

[0021] According to still another aspect of the present application, the present application provides a computer readable storage medium, the storage medium storing a computer program, the program being executed by a processor to implement the method of any one of the above aspects of the present application.

[0022] According to still another aspect of the present application, an electronic device is provided, the electronic device comprising: a processor; a memory for storing executable instructions of the processor; the processor is configured to read the executable instructions from the memory and execute the instructions to implement the method of any one of the above aspects of the present application.

[0023] The method comprises the following steps: generating a first network matrix of a system based on parameters of various nodes in a multi-station new energy sending-out system, performing Gaussian elimination on the first network matrix, and respectively performing aggregation equivalence on generator nodes, load nodes and new energy nodes to determine a low-dimensional voltage stability analysis model of the multi-station new energy sending-out system, and determining an upper boundary of a dynamic power transmission limit of the new energy under a first power change speed of the new energy based on a first model parameter value of the low-dimensional voltage stability analysis model; performing Thevenin equivalence on the low-dimensional voltage stability analysis model from the new energy side to determine a second model parameter value of a Thevenin equivalence analysis model, and determine a lower boundary of the dynamic power transmission limit of the new energy under a second power change speed of the new energy based on the second model parameter value, and finally, based on the dynamic power transmission limit model of the multi-station new energy, according to the upper boundary and the lower boundary, and the corresponding first and second power change speeds of the new energy, determine an expression for calculating the dynamic power transmission limit of the multi-station new energy. The method and system construct a low-dimensional voltage stability analysis model based on the parameter values of various nodes in the multi-station new energy sending-out system, and determine the upper boundary and the lower boundary of the power transmission limit of the multi-station new energy sending-out system based on the response characteristics of the grid-connected system under different fluctuation speeds of the new energy power by performing Thevenin value equivalence on the low-dimensional voltage stability analysis model, and determine the model for calculating the dynamic power transmission limit of the multi-station new energy based on the upper boundary and the lower boundary and the corresponding power change speed of the new energy, realize the dynamic analysis of the new energy power transmission limit, so as to help the power grid dispatchers to predict the operation risk of the system in advance in terms of safe and stable operation of the power system, avoid voltage instability and other problems caused by fluctuation of new energy power, and effectively improve the risk resistance ability of the power grid. From the perspective of new energy consumption, accurate power transmission limit calculation can fully tap the transmission potential of the system, guide the planning of reasonable power generation plan of the new energy station, and improve the utilization rate of new energy. BRIEF DESCRIPTION OF DRAWINGS

[0024] The exemplary embodiments of the present application can be more completely understood by reference to the following drawings:

[0025] Figure 1 The flow chart of the method for calculating the dynamic power transmission limit of the multi-station new energy according to the preferred embodiment of the present application;

[0026] Figure 2 The structure diagram of the low-dimensional voltage stability model of the multi-station new energy sending-out system according to the preferred embodiment of the present application;

[0027] Figure 3 The structure diagram of the first Thevenin equivalence analysis model corresponding to the low-dimensional voltage stability model of the multi-station new energy sending-out system according to the preferred embodiment of the present application;

[0028] Figure 4 Structure diagram of a power equivalent analysis model corresponding to a low-dimensional voltage stability model of a multi-station new energy sending-out system according to a preferred embodiment of the present application;

[0029] Figure 5 Structure diagram of the power equivalent analysis model after power splitting according to the preferred embodiment of the present application;

[0030] Figure 6 Structure diagram of a second Thevenin equivalent analysis model corresponding to a low-dimensional voltage stability model of a multi-station new energy sending-out system according to a preferred embodiment of the present application;

[0031] Figure 7 Structure diagram of a multi-station new energy sending-out dynamic power transmission limit calculation system according to a preferred embodiment of the present application;

[0032] Figure 8 Structure diagram of an electronic device according to a preferred embodiment of the present application. DETAILED DESCRIPTION

[0033] Reference will now be made to the drawings to describe the exemplary embodiments of the present application in detail. The present application may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and fully convey the scope of the application to those skilled in the art. The terminology used in the description of the exemplary embodiments presented herein is not intended to be limiting. Rather, the terminology is used by describing the exemplary embodiments with a level of particularity currently known. Embodiments of the present application are described herein with reference to the accompanying drawings; however, various changes and modifications could be suggested to one skilled in the art, and it is intended that the present application encompass such changes and modifications as fall within the scope of the appended claims. Throughout the drawings, the same reference designations are used for like or similar elements.

[0034] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and the present disclosure, and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

[0035] Exemplary method

[0036] Figure 1 Flow chart of a multi-station new energy sending-out dynamic power transmission limit calculation method according to a preferred embodiment of the present application. As shown in Figure 1 the flow chart, the multi-station new energy sending-out dynamic power transmission limit calculation method according to the preferred embodiment of the present application starts from step 101.

[0037] In step 101, a first network matrix of the multi-station new energy sending-out system is established according to the self-admittance matrix, the voltage column vector and the current column vector of the generator nodes, the load nodes, the new energy nodes and other nodes contained in the multi-station new energy sending-out system, and the mutual admittance between the nodes.

[0038] Preferably, the first network matrix of the multi-station new energy sending-out system is established according to the self-admittance matrix, the voltage column vector and the current column vector of the generator nodes, the load nodes, the new energy nodes and other nodes contained in the multi-station new energy sending-out system, and the mutual admittance between the nodes, wherein the expression of the first network matrix is:

[0039]

[0040] In the formula, Y GG , U G and I G are respectively the self-admittance matrix, the voltage column vector and the current column vector of the m generator nodes; Y LL , U L and I L are respectively the self-admittance matrix, the voltage column vector and the current column vector of the n load nodes; Y RR , U R and I R are respectively the self-admittance matrix, the voltage column vector and the current column vector of the f new energy nodes; Y OO , U O and I O are respectively the self-admittance matrix, the voltage column vector and the current column vector of other nodes, I O is equal to 0; Y GL , Y GR , Y GO , Y LR , Y LO , Y RO are mutual admittances between the four types of nodes.

[0041] In step 102, the other nodes in the first network matrix are subjected to Gaussian elimination, and a second network matrix of a low-dimensional new energy sending-out system is established.

[0042] Preferably, the other nodes in the first network matrix are subjected to Gaussian elimination, and a second network matrix of a low-dimensional new energy sending-out system is established, wherein the expression of the second network matrix is:

[0043]

[0044] In the formula, , Y N and are as follows:

[0045]

[0046] .

[0047] In step 103, the generator nodes, the load nodes and the new energy nodes in the second network matrix are respectively aggregated and equivalent, and a low-dimensional voltage stability analysis model of the multi-station new energy sending-out system and first model parameter values of the low-dimensional voltage stability analysis model are determined by using a matrix transformation dimension reduction method of voltage mean value and current summation, the low-dimensional voltage stability analysis model including a system side, a load side and a new energy side after the generator nodes, the load nodes and the new energy nodes are respectively aggregated.

[0048] Preferably, the generator nodes, the load nodes and the new energy nodes in the second network matrix are respectively aggregated and equivalent, and a low-dimensional voltage stability analysis model of the multi-station new energy sending-out system and first model parameter values of the low-dimensional voltage stability analysis model are determined by using a matrix transformation dimension reduction method of voltage mean value and current summation, wherein:

[0049] In the low-dimensional voltage stability analysis model, the generator nodes are equivalent to an infinite grid, the bus voltage amplitude of which is U g , the system side of the low-dimensional voltage stability analysis model; the new energy nodes are equivalent to equivalent new energy, the bus voltage amplitude of the outlet side of which is U r , the new energy side of the low-dimensional voltage stability analysis model; and the load nodes are equivalent to equivalent load, the voltage amplitude of which is U l , the load side of the low-dimensional voltage stability analysis model; the infinite grid is connected with the equivalent new energy through an equivalent reactance X s of the transmission line, the power of the equivalent new energy is processed by boosting, and is connected with the system through an equivalent reactance X R of the new energy node, the power of the infinite grid is combined, and the combined power is connected with the system through an equivalent reactance X L of the load node, wherein the active power of the equivalent new energy and the equivalent load is P R and P L , respectively, the first model parameters include the bus voltage of the infinite grid, the voltage of the equivalent load, the active power of the equivalent new energy and the equivalent load, the equivalent reactance of the transmission line, and the equivalent reactance of the equivalent new energy connected with the system.

[0050] Figure 2 FIG. 1 is a structural schematic diagram of a low-dimensional voltage stability model of a multi-station new energy sending-out system according to a preferred embodiment of the present application. The multi-station new energy sending-out system includes m generator nodes, n load nodes and f new energy nodes, and according to the low-dimensional voltage stability model of the multi-station new energy sending-out system, the generator nodes are equivalent to an infinite grid, the bus voltage amplitude of which is U Figure 2It can be seen that the new energy node is the wind farm. The low-dimensional voltage stability model obtained by aggregating and equivalencing the second network matrix of the multi-station new energy transmission system after Gaussian elimination is as follows: Figure 2 As shown in the figure, this model combines an infinite power grid with a wind farm (equivalent new energy source) to supply power to an equivalent load. The infinite power grid is connected to the wind farm's power supply via a reactor Xs. The wind farm's power is collected, stepped up, and then supplied through the reactor Xs. R The power is then combined with the power of the infinite grid, and then the power is transmitted through reactance X. L The load flows to the equivalent load. The equivalent load model in the figure is represented by a first-order differential equation from the DAE equations. In the figure, Ug is the bus voltage amplitude of the infinite power grid; Ur is the bus voltage amplitude at the output side of the equivalent renewable energy source; Uc is the bus voltage amplitude after the infinite power source and the equivalent renewable energy source are combined; U l X is the bus voltage amplitude of the equivalent load; Xs is the equivalent reactance of the transmission line; X R Equivalent reactance for the new energy node access system; X L The equivalent reactance of the load node connected to the system; G R XC is the equivalent conductance of the load node, and P is the capacitor used to compensate for the power factor to ensure steady-state operation of the load node. L、 Q L Let these be the active power and reactive power of the equivalent load, respectively. The DAE equation for this model is then written, and the expression for the first-order differential equation is:

[0051]

[0052] The expression for the algebraic equation is:

[0053]

[0054]

[0055]

[0056]

[0057]

[0058]

[0059]

[0060]

[0061]

[0062]

[0063] wherein T G , P L0 , P g , P R , P L , Q g , Q R , Q L are obtained by summing and considering weights in the process of polymerization, wherein a i is the weight of the ith load node, and , T Gi is the recovery time constant of the ith load node, P L0i is the initial active power of the ith load node, P Li , Q Li are the active and reactive power of the ith load node, respectively; P gj , Q gj are the active and reactive power of the jth generator node, respectively; P Re , Q Re are the active and reactive power of the eth new energy node, respectively, k e is the active power change slope of the eth new energy node, P R0e is the initial active power of the eth new energy node.

[0064] The low-dimensional stable voltage analysis model of the multi-station new energy according to the second network matrix and the first model parameter value of the low-dimensional voltage stability analysis model are realized by the corresponding technical solutions in the prior art, and thus will not be described here.

[0065] Figure 3 is a structural schematic diagram of the first Thevenin equivalent analysis model corresponding to the low-dimensional voltage stability model of the multi-station new energy sending-out system according to the preferred embodiment of the application. As Figure 3 shown, when the low-dimensional voltage stability analysis model is subjected to Thevenin equivalent from the load port to the system side and the new energy side, the equivalent new energy is regarded as a power source, and thus is equivalent to a current source controlled by the voltage at the terminal of the new energy in the equivalent process. Then, according to the Thevenin equivalent analysis model, the voltage expression of the equivalent load is:

[0066]

[0067] As can be seen from the above formula, the voltage of the equivalent load is a function of the Thevenin equivalent potential , the Thevenin equivalent reactance X th , and the load conductance G R , and the expression is:

[0068]

[0069] Further, the amplitude E of the Thevenin equivalent potential th and the equivalent reactance X th The expression is as follows:

[0070]

[0071]

[0072] Then according to the Thevenin equivalent potential E above th and the equivalent load voltage The new expression of the equivalent load voltage is obtained as follows:

[0073]

[0074] Substitute the new expression of the equivalent load voltage into the first-order differential equation of the low-dimensional stable voltage analysis model to obtain the new first-order differential equation expression as follows:

[0075]

[0076] Let P R = kt + P R0 = τ, where , then kdt = dτ, substitute into the new first-order differential equation expression to obtain the latest first-order differential equation expression as follows:

[0077]

[0078] The latest first-order differential equation expression can be changed to obtain the first-order derivative formula of G R as follows:

[0079]

[0080] From the first-order derivative formula of G R , when the equivalent new energy power changes rapidly, that is, k tends to infinity, tends to 0, indicating that the equivalent conductance G R of the load node is constant, that is, the load response characteristic is constant impedance, at this time the system shows high resistance ratio characteristic; when the equivalent new energy power changes slowly, that is, k tends to 0, the left side of the latest first-order differential equation expression tends to 0, indicating that the equivalent load power tends to the initial active power P L0 , that is, the load response characteristic is constant power. According to the characteristics in the above two extreme cases, the dynamic system under the two extreme responses can be simplified as a static system for analysis, and then the power transmission limit is analyzed, and the possibility of full-time scale power limit analysis is further explored.

[0081] At step 104, the upper limit of the dynamic power transmission limit of the multi-station new energy external transmission under the first power change speed of the new energy is determined according to the first model parameter value calculation.

[0082] Preferably, the upper limit of the dynamic power transmission limit of the multi-station new energy external transmission under the first power change speed of the new energy is determined according to the first model parameter value calculation, and the calculation formula is:

[0083]

[0084] In the formula, P max1 is the upper limit of the power transmission limit of the multi-station new energy transmission system.

[0085] Figure 4 is the structure diagram of the power equivalent analysis model corresponding to the low-dimensional voltage stability model of the multi-station new energy transmission system according to the preferred embodiment of the application. When the equivalent new energy power change speed is particularly small, according to the above analysis, the equivalent load presents a constant power response characteristic, and the power equivalent model of the low-dimensional equivalent voltage analysis model is as shown in Figure 4 , the equivalent new energy transmission power P Rmax is collected and sent to the infinite grid and the equivalent load through the reactance X R At this time, since the equivalent load is approximately constant power, its value is P L . Because the main grid and the load are coupled branches in practice, the new energy external transmission power limit cannot be analytically solved. According to the power flow constraint in the power network equation, it can be decoupled into a single-branch power receiving model, and the power-coupled line is decoupled into two lines for power transmission.

[0086] Figure 5 is the structure diagram after the power analysis model is split according to the preferred embodiment of the application. As shown in Figure 5 , the equivalent reactance X R is split into X R1 and X R2 , and the power P Rmax of the equivalent new energy is split into P L flowing to the load and P Rmax1 flowing to the infinite grid. In order to ensure the equivalence of the model before and after splitting, the reactance splitting needs to meet the following two conditions:

[0087] ① After decoupling, the active power flowing through the reactances X R1 and X R2 should meet the following power transmission expression:

[0088]

[0089] Where P is the active power of line transmission, δ is the power angle difference between both ends, X is the X R1 and X R2 .

[0090] ②Decoupled X R1 and X R2 in parallel should be equal to X R , that is, the following formula is satisfied:

[0091]

[0092] According to the above two power splitting conditions, and Figure 5 the following formula can be obtained:

[0093]

[0094]

[0095] The formula of X R1 and P Rmax1 can be obtained:

[0096]

[0097] Thus, when the slow fluctuation of new energy power occurs, the expression of the external sending power limit P max1 is as follows:

[0098] .

[0099] When the load response characteristic is constant power, with the decrease of the load node voltage, the load current increases, that is, the load resistance decreases, at this time, the power transmission limit of the system increases, so when the load is constant power, the corresponding power transmission limit P max1 is taken as the upper limit of the dynamic power transmission limit.

[0100] In step 105, for the low-dimensional voltage stability analysis model, the load side is equivalent to an equivalent resistance, and the system side and the load side are Thevenin equivalent from the new energy side, and after generating the Thevenin equivalent analysis model, the second model parameter value of the Thevenin equivalent analysis model is determined according to the first model parameter value.

[0101] Preferably, the second model parameter value of the Thevenin equivalent analysis model is determined according to the first model parameter value, wherein:

[0102] The second model parameter in the Thevenin equivalent analysis model includes Thevenin equivalent potential and Thevenin equivalent impedance Z, and the calculation formulas are respectively:

[0103]

[0104]

[0105]

[0106] In the formula, R L The equivalent resistance of the load side in the Thevenin equivalent analysis model. This is the bus voltage of an infinitely large power grid.

[0107] In step 106, the lower boundary of the dynamic power transmission limit of new energy transmission from multiple power stations is calculated and determined based on the second model parameter value, wherein the second power change rate of new energy is greater than the first power change rate of new energy.

[0108] Preferably, the lower boundary of the dynamic power transmission limit of new energy transmission from multiple power plants under the second power change rate of new energy is calculated and determined based on the parameter values ​​of the second model. The calculation formula is as follows:

[0109]

[0110] In the formula, P max2 Let E be the lower boundary of the power transmission limit of the multi-station renewable energy transmission system, and E be the Thevenin equivalent potential. The amplitude.

[0111] Figure 6 This is a schematic diagram of the second Thevenin equivalent analysis model corresponding to the low-dimensional voltage stability model of the multi-station renewable energy transmission system according to a preferred embodiment of the present invention. When the equivalent renewable energy power changes at a particularly high rate, according to the above analysis, the equivalent load exhibits a constant impedance response characteristic. Let the equivalent resistance of the load be R. L The equivalent power of new energy transmitted to other regions is P. Rmax2 Then, the Thevenin equivalent method can be used to analytically calculate the power transmitted from new energy sources. For example... Figure 6 As shown, Thevenin equivalent potential The expression for the equivalent reactance Z is as follows:

[0112]

[0113]

[0114] Therefore, when the equivalent new energy power fluctuates rapidly, its external power limit P can be obtained. max2 The expression is as follows:

[0115]

[0116] In the formula, E is the Thevenin equivalent electric potential. the amplitude of the equivalent impedance Z, and φ is the power factor angle of the load.

[0117] In summary, when the load exhibits constant impedance characteristics, in the process of equivalent new energy power growth, the system voltage decreases, resulting in a decrease in load power, and the new energy power originally consumed locally at the load is instead transmitted remotely to the system side, weakening the voltage stability of the system. Therefore, the corresponding power transmission limit P max2 is low, so the corresponding power transmission limit P max2 can be taken as the lower boundary of the outgoing dynamic power limit.

[0118] In step 107, based on the multi-station new energy outgoing dynamic power transmission limit model, according to the upper and lower boundaries and the corresponding first and second new energy power change speeds, an expression for calculating the multi-station new energy outgoing dynamic power transmission limit in the multi-station new energy sending-out system is determined.

[0119] Preferably, based on the multi-station new energy outgoing dynamic power transmission limit model, according to the upper and lower boundaries and the corresponding first and second new energy power change speeds, an expression for calculating the multi-station new energy outgoing dynamic power transmission limit is determined, wherein the expression of the model of the multi-station new energy outgoing dynamic power transmission limit is:

[0120]

[0121] wherein T G is the recovery time constant of the equivalent load in the low-dimensional voltage stability analysis model, and the value is the sum of the recovery time constants of all load nodes in the system. When a nonlinear interpolation method is used, the value of P Rmax is the upper and lower boundaries, the value of k is the first and second new energy power change speeds. After determining the parameters b and k0 in the above expression, the power transmission limit value of the multi-station new energy sending-out system at any new energy power change speed can be calculated according to the determined expression of the multi-station new energy outgoing dynamic power transmission limit.

[0122] In order to verify the effectiveness of the calculation method described in the present application, a multi-station new energy sending-out system of a certain actual power grid is taken as an example for illustration. Table 1 is a table of equivalent system operating parameters of a certain actual power grid.

[0123] Table 1

[0124]

[0125] Based on the operating parameters in Table 1, the new energy outgoing power limit value is calculated at different new energy power change speeds using the present method and simulation, respectively, and the results are shown in Table 2.

[0126] Table 2

[0127]

[0128] From Table 2, it can be seen that the difference of the transmission power limit of the AC export channel obtained by simulation is 9.6% under the first power fluctuation speed of 0.1 MW / s and the second power fluctuation speed of 135 MW / s, indicating the research significance of the dynamic power transmission limit calculation method. By using the method described in the application, the errors of the power limit of the wind farm under the slow and fast fluctuation with the power fluctuation speed difference of more than 1000 times are 0.70% and 0.97% respectively, indicating the calculation accuracy of the method.

[0129] Based on the calculation values under the two new energy power fluctuation speeds in Table 2, that is, P max1 is 5.77, P max2 is 5.13, the expression of the new energy export dynamic power limit of the system can be obtained by using the nonlinear interpolation method as follows:

[0130]

[0131] After determining the expression of the new energy export dynamic power limit of the system based on the data in Table 2, the export power limit under any new energy power change speed can be calculated, and compared with the simulation value of the export power limit under the corresponding new energy power change speed to determine the error percentage, and the specific results are shown in Table 3.

[0132] Table 3

[0133]

[0134] From Table 3, it can be seen that the maximum error of the power transmission limit obtained by simulation and formula calculation is 1.33%, verifying the accuracy of the analytical calculation method of the preferred embodiment. At the same time, with the increase of the new energy power change speed, the export power limit gradually decreases, indicating that the stable boundary of the system under high resistance ratio is reduced.

[0135] The calculation method of the dynamic power transmission limit of the multi-station new energy external transmission of the preferred embodiment is based on the parameter values of various nodes of the multi-station new energy sending-out system to construct a low-dimensional voltage stability analysis model, and through the Thevenin equivalent of the low-dimensional voltage stability analysis model, the upper and lower boundaries of the power transmission limit of the multi-station new energy sending-out system are determined based on the response characteristics of the grid-connected system under different fluctuation speeds of new energy power, and according to the upper and lower boundaries and the corresponding new energy power change speed, the model for calculating the dynamic power transmission limit of the multi-station new energy external transmission is determined, which realizes the dynamic analysis of the new energy external transmission power transmission limit, thereby in the aspect of safe and stable operation of the power system, it can help the power grid dispatchers to predict the operation risk of the system in advance, avoid voltage instability and other problems caused by new energy power fluctuation, and effectively improve the risk resistance ability of the power grid; From the perspective of new energy consumption, accurate power transmission limit calculation can fully tap the transmission potential of the system, guide the new energy station to plan a reasonable power generation plan, improve the utilization rate of new energy, and thus promote the realization of the double carbon target.

[0136] Exemplary system

[0137] Figure 7 The structure diagram of the calculation system of the dynamic power transmission limit of the multi-station new energy external transmission according to the preferred embodiment of the application is shown in FIG. 7. Figure 7 As shown in the figure, the calculation system 700 of the dynamic power transmission limit of the multi-station new energy external transmission according to the preferred embodiment of the application comprises:

[0138] A first matrix module 701 is configured to establish a first network matrix of the multi-station new energy sending-out system according to the self-inductance matrix, voltage column vector and current column vector of the generator node, load node, new energy node and other nodes contained in the multi-station new energy sending-out system, and the mutual inductance between the nodes;

[0139] A second matrix module 702 is configured to perform Gaussian elimination on the other nodes in the first network matrix to establish a second network matrix of the low-dimensional new energy sending-out system;

[0140] A first model module 703 is configured to respectively aggregate and equivalent the generator node, load node and new energy node in the second network matrix, determine a low-dimensional voltage stability analysis model of the multi-station new energy sending-out system and a first model parameter value of the low-dimensional voltage stability analysis model by using a matrix transformation dimension reduction method of voltage mean value and current summation, and the low-dimensional voltage stability analysis model comprises the system side, load side and new energy side generator node, load node and new energy node after the aggregation of the generator node, load node and new energy node, respectively, and the aggregation and equivalent of the generator node, load node and new energy node;

[0141] The first boundary module 704 is configured to calculate an upper boundary of a dynamic power transmission limit of the new energy power transmission system under a first power change speed of the new energy according to the first model parameter value.

[0142] The second model module 705 is configured to equivalently set the load side as an equivalent resistor and perform Thevenin equivalence on the system side and the load side from the new energy side to generate a Thevenin equivalence analysis model, and determine a second model parameter value of the Thevenin equivalence analysis model according to the first model parameter value.

[0143] The second boundary module 706 is configured to calculate a lower boundary of the power transmission limit of the new energy power transmission system according to the second model parameter value, where the second power change speed of the new energy is greater than the first power change speed of the new energy.

[0144] The result output module 707 is configured to determine an expression for calculating the dynamic power transmission limit of the new energy power transmission system according to the upper boundary and the lower boundary and the first and second power change speeds of the new energy based on the dynamic power transmission limit model of the new energy power transmission system.

[0145] Preferably, the first matrix module 701 establishes the first network matrix of the new energy power transmission system according to the self-admittance matrix, the voltage column vector and the current column vector of the generator node, the load node, the new energy node and other nodes in the new energy power transmission system and the mutual admittance between the nodes, where the expression of the first network matrix is as follows:

[0146]

[0147] In the formula, Y GG , U G and I G are the self-admittance matrix, the voltage column vector and the current column vector of the m generator nodes; Y LL , U L and I L are the self-admittance matrix, the voltage column vector and the current column vector of the n load nodes; Y RR , U R and I R are the self-admittance matrix, the voltage column vector and the current column vector of the f new energy nodes; Y OO , U O and I O are the self-admittance matrix, the voltage column vector and the current column vector of other nodes, and I O is equal to 0; Y GL , Y GR , Y GO , Y LR , YLO , Y RO is the mutual admittance between the four types of nodes.

[0148] Preferably, the second matrix module 702 performs Gaussian elimination on other nodes in the first network matrix to establish a second network matrix of the low-dimensional new energy sending-out system, wherein the expression of the second network matrix is:

[0149]

[0150] wherein, , Y N and The expression is as follows:

[0151]

[0152] .

[0153] Preferably, the first model module 703 respectively aggregates and equivalences the generator nodes, the load nodes and the new energy nodes in the second network matrix, adopts a matrix transformation dimension reduction method of voltage mean value and current summation to determine a low-dimensional voltage stability analysis model of the multi-station new energy sending-out system and a first model parameter value of the low-dimensional voltage stability analysis model, wherein:

[0154] In the low-dimensional voltage stability analysis model, the generator nodes are equivalent to an infinite grid, the bus voltage amplitude of which is U g , which is the system side of the low-dimensional voltage stability analysis model; the new energy nodes are equivalent to equivalent new energy, the export side bus voltage amplitude of which is U r , which is the new energy side of the low-dimensional voltage stability analysis model; and the load nodes are equivalent to equivalent load, the voltage amplitude of which is U l , which is the load side of the low-dimensional voltage stability analysis model; the infinite grid is connected with the equivalent new energy through the equivalent reactance X s of the transmission line, the power of the equivalent new energy is processed by boosting, and is connected with the infinite grid through the equivalent reactance X R of the new energy node, the power after the combination is connected with the equivalent load through the equivalent reactance X L of the load node, wherein the active power of the equivalent new energy and the equivalent load is P R and P L , respectively, the first model parameter includes the bus voltage of the infinite grid, the voltage of the equivalent load, the active power of the equivalent new energy and the equivalent load, the equivalent reactance of the transmission line, and the equivalent reactance of the equivalent new energy connected with the system.

[0155] Preferably, the first boundary module 704 determines the upper boundary of the dynamic power transmission limit of the new energy power transmission system of the multi-field station according to the first model parameter value and the first power change rate of the new energy, and the calculation formula is:

[0156]

[0157] wherein, P max1 is the upper boundary of the dynamic power transmission limit of the new energy power transmission system of the multi-field station.

[0158] Preferably, the second model module 705 determines the second model parameter value of the Thevenin equivalent analysis model according to the first model parameter value, wherein:

[0159] The second model parameter in the Thevenin equivalent analysis model includes Thevenin equivalent voltage and Thevenin equivalent impedance , and the calculation formula is respectively:

[0160]

[0161]

[0162]

[0163] wherein, is the equivalent resistance of the load side in the Thevenin equivalent analysis model, is the bus voltage of the infinite grid.

[0164] Preferably, the second boundary module 706 determines the lower boundary of the dynamic power transmission limit of the new energy power transmission system of the multi-field station according to the second model parameter value and the second power change rate of the new energy, and the calculation formula is:

[0165]

[0166] wherein, P max2 is the lower boundary of the dynamic power transmission limit of the new energy power transmission system of the multi-field station, E is the amplitude of the Thevenin equivalent voltage , θ is the impedance angle of the equivalent impedance Z, and φ is the load power factor angle.

[0167] Preferably, the result output module 707 determines the expression for calculating the dynamic power transmission limit of the new energy power transmission system of the multi-field station according to the upper boundary and the lower boundary and the corresponding first and second power change rates of the new energy based on the dynamic power transmission limit model of the new energy power transmission system of the multi-field station, and the expression of the model of the dynamic power transmission limit of the new energy power transmission system of the multi-field station is:

[0168]

[0169] wherein T G is the restoration time constant of the equivalent load in the low-dimensional voltage stability analysis model, and the value is the sum of the restoration time constants of all load nodes in the system, when a nonlinear interpolation method is adopted, based on P Rmax The value of k corresponding to the upper and lower boundaries is the first and second power change speed of the new energy. After determining the parameters b and k0 in the above expression, the power transmission limit value of the multi-station new energy sending-out system at any new energy power change speed can be calculated according to the determined expression of the multi-station new energy sending-out dynamic power transmission limit.

[0170] The calculation system of the multi-station new energy sending-out dynamic power transmission limit of the preferred embodiment and the calculation method of the multi-station new energy sending-out dynamic power transmission limit determine the same step of calculating the model for calculating the multi-station new energy sending-out dynamic power transmission limit, and achieve the same technical effects, which will not be repeated here.

[0171] Exemplary electronic device

[0172] Figure 8 is a structural schematic diagram of an electronic device according to the preferred embodiment of the present application. As shown in Figure 8 , the electronic device includes one or more processors 801 and a memory 802.

[0173] The processor 801 can be a central processing unit (CPU) or other forms of processing units having data processing and / or instruction execution capabilities, and can control other components in the electronic device to perform desired functions.

[0174] The memory 802 can include one or more computer program products, which can include various forms of computer readable storage media, such as volatile memory and / or non-volatile memory. The volatile memory may, for example, include random access memory (RAM) and / or cache memory, etc. The non-volatile memory may, for example, include read-only memory (ROM), hard disk, flash memory, etc. One or more computer program instructions can be stored on the computer readable storage medium, and the processor 801 can run the program instructions to implement the calculation method of the multi-station new energy sending-out dynamic power transmission limit of the disclosed various embodiments and / or other desired functions described above. In one example, the electronic device can further include an input device 803 and an output device 804, and these components are interconnected by a bus system and / or other forms of connection mechanism (not shown).

[0175] In addition, the input device 803 can also include, for example, a keyboard, a mouse, etc.

[0176] The output device 804 can externally output various information. The output device 804 can include, for example, a display, a speaker, a printer, and a communication network and a remote output device connected thereto, etc.

[0177] Of course, in order to simplify, Figure 8 Only some of the components of the electronic device related to the present disclosure are shown in the middle, and components such as buses, input / output interfaces, etc. are omitted. In addition, the electronic device can further include any other appropriate components according to the specific application.

[0178] Exemplary computer program product and computer readable storage medium

[0179] In addition to the above-mentioned methods and devices, the embodiments of the present disclosure can also be a computer program product, which includes computer program instructions that, when executed by a processor, cause the processor to perform the steps in the calculation method of the multi-station new energy sending dynamic power transmission limit according to various embodiments of the present disclosure described in the above "Exemplary Methods" section of the specification.

[0180] The computer program product can be written in any combination of one or more programming languages to perform the operations of the embodiments of the present disclosure, including object-oriented programming languages such as Java, C++, etc., and conventional procedural programming languages such as "C" language or similar programming languages. Program code can be executed entirely on a user computing device, partially on a user device, as a separate software package, partially on a user computing device and partially on a remote computing device, or entirely on a remote computing device or server.

[0181] In addition, the embodiments of the present disclosure can also be a computer readable storage medium having stored thereon computer program instructions, which when executed by a processor, cause the processor to perform the steps in the calculation method of the multi-station new energy sending dynamic power transmission limit according to various embodiments of the present disclosure described in the above "Exemplary Methods" section of the specification.

[0182] The computer readable storage medium can be any combination of one or more computer readable medium(s). The computer readable medium can be a computer readable signal medium or a computer readable storage medium. A computer readable storage medium can be, for example, but not limited to, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any suitable combination of the foregoing. More specific examples (a non-exhaustive list) of the computer readable storage medium include an electrical connection having one or more wires, a portable disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disc read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.

[0183] The above generally describes the basic principles of the disclosure in conjunction with specific embodiments, but it should be noted that the advantages, benefits, effects and the like mentioned in the disclosure are only examples and are not limiting, and these advantages, benefits, effects and the like cannot be considered as the various embodiments of the disclosure must have. In addition, the specific details of the above disclosure are only for the purpose of example and for the purpose of understanding, and the above details do not limit the disclosure to the above specific details.

[0184] Each embodiment in the specification is described in a progressive manner, and each embodiment focuses on the difference from other embodiments. The same or similar parts between each embodiment can be referred to each other. For system embodiments, since they basically correspond to method embodiments, the description is relatively simple, and the relevant parts can be referred to the part of the method embodiment.

[0185] The block diagrams of the devices, apparatuses, equipment, systems involved in the disclosure are only illustrative examples and are not intended to require or imply the connection, arrangement, configuration shown in the block diagram. As those skilled in the art will recognize, these devices, apparatuses, equipment, systems can be connected, arranged, configured in any manner. Words such as "include", "contain", "have" and the like are open-ended words, which mean "include but not limited to", and can be used interchangeably. The words "or" and "and" used herein mean the word "and / or", and can be used interchangeably unless the context clearly indicates otherwise. The word "such as" used herein means the phrase "such as but not limited to", and can be used interchangeably.

[0186] The apparatus and methods of the present disclosure can be implemented in numerous ways. For example, the apparatus and methods of the present disclosure can be implemented using software, hardware, firmware, or any combination of software, hardware, and firmware. The order of any steps of the methods described above is merely exemplary and the steps of the methods of the present disclosure need not be performed in the order described unless otherwise specified. Furthermore, in some embodiments, the present disclosure can also be implemented as a program for use with a computer-based system, the program including a machine-readable instruction for implementing the methods according to the present disclosure. Thus, the present disclosure also covers record media storing the program for implementing the methods according to the present disclosure.

[0187] It is also noted that the apparatus, devices, and methods of the present disclosure can be embodied in a variety of ways. In addition, the division and / or combination of the components or steps in the apparatus, devices, and methods of the present disclosure should be considered as equivalent. The above description of the disclosed aspects is provided to enable any person skilled in the art to make or use the present disclosure. Various modifications to these aspects will be readily apparent to those skilled in the art, and the generic principles defined herein can be applied to other aspects without departing from the scope of the present disclosure. Thus, the present disclosure is not intended to be limited to the aspects shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

[0188] The above description has been presented for the purposes of illustration and description. Furthermore, this description is not intended to limit the embodiments of the present disclosure to the forms disclosed herein. Although several example aspects and embodiments have been discussed above, those of ordinary skill in the art will recognize certain variations, modifications, changes, additions, and sub-combinations thereof.

Claims

1. A method for calculating the dynamic power transmission limit of multi-station renewable energy transmission, characterized in that, The method includes: The first network matrix of the multi-station renewable energy transmission system is established based on the self-admittance matrix, voltage column vector, and current column vector of the generator nodes, load nodes, renewable energy nodes, and other nodes included in the multi-station renewable energy transmission system, as well as the mutual admittance between nodes. Gaussian elimination is performed on the other nodes in the first network matrix to establish a second network matrix for the low-dimensional new energy transmission system. The generator nodes, load nodes, and new energy nodes in the second network matrix are aggregated and equalized respectively. The matrix transformation dimensionality reduction method of voltage mean and current summation is used to determine the low-dimensional voltage stability analysis model of the multi-station new energy transmission system, as well as the first model parameter value of the low-dimensional voltage stability analysis model. The low-dimensional voltage stability analysis model includes the system side, load side, and new energy side after aggregating the generator nodes, load nodes, and new energy nodes respectively. The upper boundary of the dynamic power transmission limit of new energy transmission from multiple power stations under the first power change rate of new energy is calculated and determined based on the parameter values ​​of the first model. For the low-dimensional voltage stability analysis model, the load side is equivalent to an equivalent resistance, and Thevenin equivalence is performed on the system side and the load side from the new energy side to generate the Thevenin equivalence analysis model. Then, the second model parameter value of the Thevenin equivalence analysis model is determined according to the first model parameter value. The lower boundary of the dynamic power transmission limit of new energy transmission from multiple power plants is calculated and determined based on the parameter values ​​of the second model, where the second power change rate of new energy is greater than the first power change rate of new energy. Based on the dynamic power transmission limit model for multi-station renewable energy transmission, the expression for calculating the dynamic power transmission limit of multi-station renewable energy transmission in the multi-station renewable energy transmission system is determined according to the upper and lower boundaries and their corresponding first and second power change rates of renewable energy. The expression for the model of the dynamic power transmission limit of multi-station renewable energy transmission is as follows: In the formula, T G The recovery time constant for an average load in a low-dimensional voltage stability analysis model is the sum of the recovery time constants of all load nodes in the system. and These represent the upper and lower boundaries of the power transmission limit of a multi-station renewable energy transmission system. When using a nonlinear interpolation method, based on... When the value of is the upper boundary and the value of k corresponding to the upper boundary and the lower boundary, the first and second power change rates of new energy are determined. After determining the parameters b and k0 in the above expression, the power transmission limit value of the multi-station new energy transmission system under any new energy power change rate can be calculated according to the expression of the determined multi-station new energy transmission dynamic power transmission limit.

2. The method according to claim 1, characterized in that, Based on the self-admittance matrices, voltage column vectors, and current column vectors of the generator nodes, load nodes, renewable energy nodes, and other nodes included in the multi-station renewable energy transmission system, as well as the mutual admittances between nodes, a first network matrix of the multi-station renewable energy transmission system is established. The expression for the first network matrix is: In the formula, Y GG U G and I G Y represents the self-admittance matrix, voltage column vector, and current column vector of m generator nodes, respectively; LL U L and I L Let Y be the self-admittance matrix, voltage column vector, and current column vector of n load nodes, respectively; RR U R and I R These represent the self-admittance matrix, voltage column vector, and current column vector of f new energy nodes, respectively; Y OO U O and I O These are the self-admittance matrix, voltage column vector, and current column vector of the other nodes, respectively. O Equals 0; Y GL Y GR Y GO Y LR Y LO Y RO The mutual admittance between the four types of nodes.

3. The method according to claim 1, characterized in that, Gaussian elimination is performed on the other nodes in the first network matrix to establish a second network matrix for the low-dimensional new energy transmission system. The expression for the second network matrix is ​​as follows: In the formula, Y N and The expression is as follows: 。 4. The method according to claim 1, characterized in that, The generator nodes, load nodes, and renewable energy nodes in the second network matrix are aggregated and equalized. A matrix transformation dimensionality reduction method using voltage mean and current summation is employed to determine the low-dimensional voltage stability analysis model of the multi-station renewable energy transmission system, along with the first model parameter values ​​of the low-dimensional voltage stability analysis model, wherein: In the low-dimensional voltage stability analysis model, the generator node is equivalent to an infinitely large power grid, and its bus voltage amplitude is U. g , which is the system side of the low-dimensional voltage stability analysis model; the new energy node is equivalent to an equivalent new energy source, and its output side bus voltage amplitude is U. r , representing the new energy side of the low-dimensional voltage stability analysis model; and the load node is equivalent to an equivalent load, with a voltage amplitude of U. l , representing the load side of the low-dimensional voltage stability analysis model; the equivalent reactance X of the infinite power grid through the transmission line. s The system connects to an equivalent renewable energy source, whose power is boosted and then connected to the system via the equivalent reactance X of the renewable energy node. R The power is combined with the infinite power grid, and the combined power is connected to the system via the equivalent reactance X at the load node. L The power flows to the equivalent load, where the active power of the equivalent renewable energy and the equivalent load are respectively P R and P L The first model parameters include the bus voltage of the infinite power grid, the voltage of the equivalent load, the active power of the equivalent new energy and the equivalent load, the equivalent reactance of the transmission line, and the equivalent reactance of the equivalent new energy access system.

5. The method according to claim 4, characterized in that, The upper boundary of the dynamic power transmission limit of multi-station renewable energy transmission under the first power change rate of renewable energy is calculated and determined based on the parameter values ​​of the first model. The calculation formula is as follows: 。 6. The method according to claim 5, characterized in that, The second model parameter values ​​of the Thevenin isometry analysis model are determined based on the first model parameter values, wherein: The second model parameter in the Thevenin equivalent analysis model includes the Thevenin equivalent potential. Thevenin equivalent impedance The calculation formulas are as follows: In the formula, The equivalent resistance of the load side in the Thevenin equivalent analysis model. This is the bus voltage of an infinitely large power grid.

7. The method according to claim 6, characterized in that, The lower boundary of the dynamic power transmission limit of new energy transmission from multiple power plants under the second power change rate of new energy is determined based on the parameter values ​​of the second model. The calculation formula is as follows: In the formula, E is the Thevenin equivalent potential. The amplitude of θ is the impedance angle of the equivalent impedance Z, and φ is the load power factor angle.

8. A calculation system for the dynamic power transmission limit of multi-station renewable energy transmission, characterized in that, The system includes: The first matrix module is used to establish the first network matrix of the multi-station renewable energy transmission system based on the self-admittance matrix, voltage column vector, and current column vector of the generator nodes, load nodes, renewable energy nodes, and other nodes included in the multi-station renewable energy transmission system, as well as the mutual admittance between nodes. The second matrix module is used to perform Gaussian elimination on other nodes in the first network matrix to establish the second network matrix of the low-dimensional new energy transmission system. The first model module performs aggregation and equivalence on the generator nodes, load nodes, and new energy nodes in the second network matrix, and uses a matrix transformation dimensionality reduction method of voltage mean and current sum to determine the low-dimensional voltage stability analysis model of the multi-station new energy transmission system, as well as the first model parameter values ​​of the low-dimensional voltage stability analysis model. The low-dimensional voltage stability analysis model includes the system side after aggregating the generator nodes, load nodes, and new energy nodes, and the load side and new energy side generator nodes, load nodes, and new energy nodes are aggregated and equivalenced respectively. The first boundary module is used to calculate and determine the upper boundary of the dynamic power transmission limit of new energy transmission from multiple power plants under the first power change rate of new energy based on the parameter values ​​of the first model. The second model module is used to treat the load side as an equivalent resistance in the low-dimensional voltage stability analysis model, and to perform Thevenin equivalence on the system side and the load side from the new energy side to generate the Thevenin equivalence analysis model. Then, the second model parameter value of the Thevenin equivalence analysis model is determined according to the first model parameter value. The second boundary module is used to calculate and determine the lower boundary of the dynamic power transmission limit of new energy transmission from multiple power plants under the second power change rate of new energy, based on the parameter values ​​of the second model, wherein the second power change rate of new energy is greater than the first power change rate of new energy. The result output module is used to determine, based on the dynamic power transmission limit model of multi-station renewable energy transmission, the expression for calculating the dynamic power transmission limit of multi-station renewable energy transmission in the multi-station renewable energy transmission system, according to the upper and lower boundaries and their corresponding first and second power change rates of renewable energy. The expression for the model of the dynamic power transmission limit of multi-station renewable energy transmission is as follows: In the formula, T G The recovery time constant for an average load in a low-dimensional voltage stability analysis model is the sum of the recovery time constants of all load nodes in the system. and These represent the upper and lower boundaries of the power transmission limit of a multi-station renewable energy transmission system. When using a nonlinear interpolation method, based on... When the value of is the upper boundary and the value of k corresponding to the upper boundary and the lower boundary, the first and second power change rates of new energy are determined. After determining the parameters b and k0 in the above expression, the power transmission limit value of the multi-station new energy transmission system under any new energy power change rate can be calculated according to the expression of the determined multi-station new energy transmission dynamic power transmission limit.

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

10. An electronic device, characterized in that, include: processor; Memory used to store the processor's executable instructions; The processor is configured to read the executable instructions from the memory and execute the executable instructions to implement the method described in any one of claims 1-7.

Images