Novel rapid solving method and system for static synchronous stability security domain of electric power system

Abstract

The invention belongs to the field of electric power system synchronous stability evaluation calculation, particularly relates to a novel electric power system static synchronous stability security domain rapid solving method and system, and aims to solve the problems that static synchronous stability criteria are difficult to determine and a static synchronous security domain needs to be constructed. The method comprises the following steps: acquiring steady-state operation data of a power system as input data; calculating equivalent impedance of a power grid based on the input data, and further obtaining an attenuation coefficient of the state of the power system; and calculating the static synchronous stability security domain of the power system by adopting a prediction correction method in combination with the attenuation coefficient. According to the invention, the static synchronization stability margin of the system can be accurately quantified; the prediction correction method is used for solving the security domain, so that the influence of a concave plane on the solving accuracy is effectively eliminated, the solving speed can be remarkably improved, the calculation time is shortened, and the more accurate security domain is solved.

Description

Background Art

[0002] In recent years, with the development of photovoltaic new energy power generation technology, the proportion of distributed photovoltaics in the distribution network has increased rapidly, and the dynamic behavior has become more complex, increasing the risk of static synchronous instability of the system and affecting the utilization rate of new energy.

[0003] The impedance analysis method can effectively evaluate the static synchronous stability characteristics of new energy power generation systems, but there are two difficulties in analyzing the system stability by the impedance analysis method: one is the determination of the reference frame of the multi-parallel grid-connected converter system; the other is the selection of the stability criterion, and it is necessary to further expand the impedance analysis stability criterion.

[0004] Existing research has analyzed in detail the factors affecting static synchronous stability. Summarizing their statements, there are mainly three points: (1) The static synchronous stability of the system is affected by voltage. When a voltage dip occurs, the output power of the grid-connected converter drops sharply, and the system is prone to synchronous instability; (2) The static synchronous stability of the system is affected by the grid impedance. After the grid-connected converter is connected to the system, a higher grid impedance value will result in a smaller overall equivalent damping of the system, or even negative damping, causing low-frequency oscillations; (3) The static synchronous stability of the system is affected by the control mode and parameters of the grid-connected converter.

[0005] In the distribution network, the impedance distribution of the system and the control mode and parameters of the grid-connected converter are determined in engineering applications. Therefore, the static synchronous stability of the system is mainly affected by voltage factors. Considering that the power flow distribution in the system will affect the voltage at the grid connection point of the grid-connected converter, and thus affect the static synchronous stability of the system, it is necessary to construct a photovoltaic distribution network safety region that meets the static synchronous stability constraint conditions and can be solved quickly and reliably, providing important guidance for the power distribution and safe and stable operation of the distribution network. Summary of the Invention

[0006] To solve the above problems in the prior art, that is, the problem that it is difficult to determine the static synchronous stability criterion in the prior art and the need to construct a static synchronous safety region, in the first aspect of the present invention, a method for quickly solving the static synchronous stability safety region of a new power system is proposed. The method includes the following steps: Step S1: Obtain the steady-state operation data of the power system as input data; based on the input data, calculate the equivalent impedance of the grid, and then obtain the attenuation coefficient of the state where the power system is located; the steady-state operation data includes the voltage, current, and power of each node. The calculation method of the attenuation coefficient is: Step S11, according to the node type of the power system, combined with the input data, construct a node voltage equation; the node type includes generator nodes, tie nodes, and load nodes. Step S12: Construct the node power equation; Step S13: Combine the node voltage equation and the node power equation to obtain the relationship between the generator node voltage and current; Step S14: Select the balancing node as an equivalent infinite power grid unit, and calculate the equivalent impedance according to the relationship between the generator node voltage and current; Step S15: Calculate the attenuation coefficient in combination with the equivalent impedance; Step S2: Calculate the static synchronous stability safety region of the power system by using the prediction-correction method in combination with the attenuation coefficient.

[0007] In some preferred embodiments, the equivalent impedance is: ; where is the voltage of the balancing node unit, U G,i is the voltage phasor of the generator node i , b ik is the element in the i th row and k th column of matrix B, U G,k is the voltage phasor of the generator node k .

[0008] In some preferred embodiments, calculate the equivalent transfer function according to the equivalent impedance. The equivalent transfer function is: ; where K (s) is the equivalent transfer function, E is the identity matrix, Y inv is the converter output impedance matrix, Z g,i is the equivalent impedance.

[0009] In some preferred embodiments, the attenuation coefficient is: ; ; where: p ki is the modulus of the residue, Res[K(s), p i is the residue at p i .

[0010] In some preferred embodiments, the method of using the prediction-correction method to calculate the static synchronous stability safety region of the power system is as follows: S31. Obtain the nodes in the power system a of the single-direction power transformation direction boundary points, and calculate to obtain the set of single-direction power transformation direction boundary points N s， as the first set; S32. Let k = 1 and d = 1. Using the operating solution of any single-direction power transformation direction boundary point in the first set as the search starting point, and sequentially using the other boundary points in the first set except the search starting point as the search ending points; the subscript of the search ending point is greater than the subscript of the search starting point; k is the number of calculation iterations; S33. Based on the value of the search starting point and the value of the search ending point, calculate the predicted solution according to the predicted solution solving method; S34. Combine the predicted solution to calculate the correction direction; S35. Combine the predicted solution and the correction direction to construct and solve the critical point search model, and further obtain the correction solution; S36. Check whether there is an element in the correction solution that is less than 0. If so, complete the search for the safety domain boundary between the search starting point and the search ending point, and let d = d + 1, then jump to S37. Otherwise, k = k + 1, and jump to S34; d represents the number of new sets; S37. Put the correction solution into a new set N s,d as the second set, and determine whether the set of single-direction power transformation direction boundary points has been traversed to the P M-1 0 and P M 0 boundary points, where M is the number of nodes of the generator set. If so, jump to S38. Otherwise, jump to S34; S38. Use the second set to gradually expand as the search starting point and the search ending point; the second set is a new set into which the correction solutions are stacked in sequence; the second set is a new set into which the correction solutions are stacked in sequence; S39. Based on the newly determined search starting point and search ending point, execute S33 - S35 to obtain the correction solution, and check whether there is an element in the correction solution that is less than 0. If so, complete the search for the safety domain boundary between the search starting point and the search ending point, and jump to S40. If not, return to step S38; S40. Determine whether the last item in the second set has been traversed. If so, connect all the boundary points to form the safety domain boundary. If not, return to step S38 until the last item in the second set has been traversed and no new set is generated.

[0011] In some preferred embodiments, the method for calculating the predicted solution is as follows: ; ; In the formula: represents the predicted solution obtained from the k-th iterative calculation between the a direction and the a+1 direction; k is the number of iterative calculations; is the k prediction step size of the step; represents the boundary point with a single change in the a direction; represents the boundary point with a single change in the a+1 direction; represents the predicted solution obtained from the (k-1)-th iterative calculation between the a direction and the a+1 direction; Define the equivalent coefficient i reflects the node j and the node q The influence of the active power change on the voltage amplitude of the node ; In the formula, i and j are digital variables, For the equivalent coefficient of node analysis, i is , j is , q is , represents the change in the active power of the i-th node, represents the change in the active power of the j-th node.

[0012] In some preferred embodiments, the correction direction is calculated by the method: ; In the formula: is the predicted solution obtained from the k th calculation, is the modulus of the predicted solution obtained from the k th calculation.

[0013] In some preferred embodiments, the critical point search model is: ; In the formula: x represents the node voltage vector of the system; y represents the power vector injected into the system; f(x,y) is the AC system power flow equation; and are the upper and lower limits of the voltage amplitude of node i respectively; and are the upper and lower limits of the allowable active power change value of node i, respectively; and are the upper and lower limits of the allowable reactive power change value of node i, respectively; N a is the node set of the photovoltaic system; β a ref is the maximum allowable attenuation coefficient under stable conditions; sgn() is the sign function.

[0014] In some preferred embodiments, the correction solution is calculated by the following method: ; In the formula, is the correction step size at the k-th step.

[0015] The second aspect of the present invention provides a fast solution system for the static synchronous stability safety region of a new power system, including: a static synchronous stability margin quantization module and a static synchronous stability safety region fast solution module; The static synchronous stability margin quantization module is configured to obtain the steady-state operation data of the power system as input data; based on the input data, calculate the equivalent impedance of the power grid, and then obtain the attenuation coefficient of the state of the power system; the steady-state operation data includes the voltage, current, and power of each node; The static synchronous stability safety region fast solution module is configured to calculate the static synchronous stability safety region of the power system by using a prediction-correction method in combination with the attenuation coefficient.

[0016] Advantages of the present invention: (1) Using the attenuation coefficient index to quantify the static synchronous stability margin of the system, constructing a series of accurate equations and relationships (such as node voltage equations, node power equations, generator node voltage and current relationships, selecting the balanced node as the equivalent infinite grid unit, calculating the equivalent impedance and equivalent transfer function, and finally calculating the attenuation coefficient), and considering the actual operating conditions of the system, can accurately quantify the static synchronous stability margin of the system; (2) Using the prediction-correction method to solve the safety region and combining the superposition law, this method not only considers the power constraint conditions, but also considers the influence of the newly added current source on the system voltage, as well as factors such as the correction amount of the node injection current, and constructs a critical point search model, realizes the fitting of the safety region boundary, reduces the error from the actual boundary, effectively eliminates the concave plane, can significantly improve the solution speed, reduce the calculation time, and solve a more accurate safety region. Description of the Drawings

[0017] Other features, objects, and advantages of the present application will become more apparent from the following detailed description of non-limiting embodiments read in conjunction with the accompanying drawings: Figure 1 It is a schematic diagram of the static security region solution process of the present invention; Figure 2 It is a schematic diagram of the boundary point selection method of the present invention; Figure 3 It is a schematic diagram of the boundary region calculation logic of the present invention. Detailed implementation manners

[0018] The present application will be further described in detail below in conjunction with the drawings and embodiments. It can be understood that the specific embodiments described herein are only used to explain the related invention and are not intended to limit the invention. Additionally, it should be noted that for the sake of convenience of description, only parts related to the relevant invention are shown in the drawings.

[0019] It should be noted that, without conflict, the embodiments in the present application and the features in the embodiments can be combined with each other. The present application will be described in detail below with reference to the drawings and in conjunction with the embodiments.

[0020] For a clearer description of the method for quickly solving the static synchronous stability security region of the novel power system of the present invention, the following will expand and describe each step in the embodiments of the present invention in conjunction with Figures 1 to 3 the embodiments of the present invention.

[0021] The method for quickly solving the static synchronous stability security region of the novel power system according to the first embodiment of the present invention includes the following steps: Step S1: Obtain the steady-state operation data of the power system as input data; based on the input data, calculate the equivalent impedance of the power grid, and further obtain the attenuation coefficient of the state of the power system; the steady-state operation data includes the voltage, current, and power of each node. In this embodiment, the static synchronous stability margin of the system is quantified by the attenuation coefficient index, specifically as follows: Step S11, according to the node types of the power system, combine the input data to construct a node voltage equation; the node types include generator nodes, connection nodes, and load nodes, and the node voltage equation can be expressed as: ; Where: Y is the system node admittance matrix, I is the node current column vector, U is the node voltage column vector, L, C, and G respectively represent load nodes, connection nodes, and generator nodes; Step S12, construct a node power equation: ; ; ; Where: S L is the load power matrix, diag is the diagonal matrix, S L,i is the complex power of the load node i ; U L,i is the voltage phasor of the load node i ; Step S13: Combine the node voltage equation and the node power equation to obtain the relationship between the generator node voltage and current; ; ; It can be obtained that: ; Where: I G,i is the current phasor of the generator node i ; U G,k is the voltage phasor of the generator node k ; b ik is the element in the i th row and k th column of matrix B; Step S14: Select the balanced node as the equivalent infinite power grid unit, and calculate the equivalent impedance according to the relationship between the generator node voltage and current; ; Where: Z g,i , R g,i and L g,i are the equivalent grid impedance vector, impedance value and inductance value of the generator node i respectively, U G,k is the voltage phasor of the generator node k ; b ik is the element in the i th row and k th column of matrix B, U G,i is the voltage phasor of the generator node i ; is the voltage of the balanced node unit; Calculate the equivalent transfer function. When the system meets the static synchronous stability allowable condition, it is necessary to ensure that the real parts of the characteristic roots of the equivalent transfer function K (s) are all negative. The equivalent transfer function K (s) is: ; wherein: E is the identity matrix, and Y inv is the converter output impedance matrix; Step S15, calculate the attenuation coefficient in combination with the equivalent impedance: The attenuation coefficient is: ; ; wherein: Res[K(s), p i is the residue at p i ; p ki is the modulus of the residue, reflecting the influence degree of the pole on the system oscillation; Step S2: Calculate the static synchronous stability safety region of the power system by using the prediction-correction method in combination with the attenuation coefficient; In this embodiment, with reference to Figure 1 , taking node a as an example, the method for calculating the static synchronous stability safety region of the system by using the prediction-correction method is as follows: S31, obtain the single-direction power transformation direction boundary points of each node in the power system, and add them to the pre-constructed set of single-direction power transformation direction boundary points. There are two single-direction power transformation direction boundary points for node a , which are respectively: ; ; The single-direction power refers to the boundary points calculated under the condition that only the power of the generator set a node is changed and the power of the other generator sets remains unchanged. The set Ns of single-direction power transformation direction boundary points is obtained as the first set, that is, a set of feasible solutions that meet the operation condition requirements. Figure 2 in , , each one is a single operation solution in this direction, and M is the number of nodes of the generator sets; S32, let k = 1, d = 1, take the operation solution of any single-direction power transformation direction boundary point in the first set as the search starting point, and take the other boundary points in the first set except the search starting point as the search ending points in turn; the subscript of the search ending point is greater than the subscript of the search starting point; k is the number of calculation iterations, and d represents the number of newly added sets; S33. Calculate the predicted solution according to the predicted solution solving method based on the value of the search starting point and the value of the search ending point; ; In the formula: represents the predicted solution obtained by the k-th iterative calculation between the a direction and the a + 1 direction; k is the number of iterative calculations; is the k step prediction step size; represents the boundary point of a single change in the a direction; represents the boundary point of a single change in the a + 1 direction; represents the predicted solution obtained by the (k - 1)-th iterative calculation between the a direction and the a + 1 direction; Define the equivalent coefficient reflects the node i and the node j The influence of the active power change amount on the voltage amplitude of the node q is: ; In the formula, i and j are digital variables, is the equivalent coefficient for node analysis, i is , j is , q is , represents the change amount of the active power of the i node, represents the change amount of the active power of the j node; S34. Calculate the correction direction in combination with the predicted solution: ; In the formula: is the predicted solution obtained by the k -th calculation, is the modulus of the predicted solution obtained by the k -th calculation; S35. Construct and solve a critical point search model in combination with the predicted solution and the correction direction, and then obtain the correction solution; The critical point search model: ; In the formula: x represents the node voltage vector of the system; y represents the power vector injected into the system; f(x, y) is the AC system power flow equation; and are the upper and lower limits of the voltage amplitude of node i, respectively; and are the upper and lower limits of the allowable changed active power value of node i, respectively; and are the upper and lower limits of the allowable changed reactive power value of node i, respectively; N a is the node set of the photovoltaic system; β a ref is the maximum allowable attenuation coefficient under stable conditions; sgn() is the sign function; The sgn() sign function is: ; The corrected solution is calculated : ; In the formula, is the correction step size at the k-th step; S36. Check whether there is an element less than 0 in the corrected solution. If so, complete the search for the safety domain boundary between the search start point and the search end point, and set d = d + 1, then jump to S37. Otherwise, set K = K + 1 and jump to S34. Specifically, judge for elements. If there is a Δ P a < 0, complete the search for the safety domain boundary between the search start point , and the search end point Specifically, for elements. If there is a Δ P 1 < 0, complete the search for the safety domain boundary between the search start point and the search end point ; S37. Put the corrected solution into the new set Ns,d. Since d = d + 1, it is used as the second set, and check whether the single-direction power transformation direction boundary point set has been traversed to and boundary points. If so, jump to S38. Otherwise, jump to S34, and sequentially change the search end point , and add it to the single-direction power transformation direction boundary point set ; Change the boundary point, and the boundary point change logic is as shown in Figure 2 , change the search start point to Sequentially use as the search end point, and add it to the single-direction power transformation direction boundary point set 、 ; Replace the search starting point with In sequence with as the search ending point, add to the set of single-direction power conversion direction boundary points, ; Replace the search starting point with With as the search ending point, add to the set of single-direction power conversion direction boundary points ; Wherein ; S38. Determine the search starting point and search ending point by gradually expanding the second set; the second set is a new set that stacks the corrected solutions in sequence, that is, stacks the corrected solutions in sequence. When selecting the starting point and ending point, after traversing the Ns set, use the Ns,d set as the selection set for the starting point and ending point, and perform iterative search for the starting point and ending point in the manner of Figure 3 ; represents the corrected solution obtained by starting the search from Ns,(a - 1)M + a - m, and the traversal method is: first perform the search between and , and further perform the search between and ; S39. Based on the newly determined search starting point and search ending point, execute S33 - S35 to obtain the corrected solution, and check whether there is an element less than 0 in the corrected solution. If so, complete the search for the safety domain boundary between the search starting point and the search ending point, and jump to S40. If not, return to step S38; S40. Determine whether the last item in the second set has been traversed. If so, connect all the boundary points to form the safety domain boundary. If not, return to step S38 until the last item in the second set has been traversed and no new set is generated.

[0022] In the above embodiments, although each step is described in the above sequential order, those skilled in the art can understand that in order to achieve the effects of this embodiment, different steps do not have to be executed in such an order. They can be executed simultaneously (in parallel) or in a reversed order, and these simple changes are all within the protection scope of the present invention.

[0023] The novel power system static synchronous stability security domain fast solution system of the second embodiment of the present invention includes: a static synchronous stability margin quantization module and a static synchronous stability security domain fast solution module. The static synchronous stability margin quantization module is configured to obtain the steady-state operation data of the power system as input data; based on the input data, calculate the equivalent impedance of the power grid, and further obtain the attenuation coefficient of the state of the power system. Combined with the attenuation coefficient, a prediction-correction method is used to calculate the static synchronous stability security region of the power system.

[0024] Those skilled in the art can clearly understand that for the convenience and conciseness of description, the specific working process and related descriptions of the above-described system can refer to the corresponding process in the foregoing method embodiments, and will not be repeated here.

[0025] It should be noted that the novel power system static synchronous stability security region fast solution system provided in the above embodiments is only illustrated by the division of the above functional modules. In practical applications, the above functions can be allocated to different functional modules as needed, that is, the modules or steps in the embodiments of the present invention can be further decomposed or combined. For example, the modules in the above embodiments can be combined into one module, or further split into multiple sub-modules to complete all or part of the functions described above. For the names of the modules and steps involved in the embodiments of the present invention, they are only used to distinguish each module or step, and are not regarded as an improper limitation of the present invention.

[0026] The electronic device according to the third embodiment of the present invention includes: at least one processor; and a memory communicatively connected to at least one of the processors; wherein, the memory stores instructions executable by the processor, and the instructions are used to be executed by the processor to implement the above-mentioned static synchronous stability security region fast solution method.

[0027] The computer-readable storage medium according to the fourth embodiment of the present invention stores computer instructions, and the computer instructions are used to be executed by the computer to implement the above-mentioned novel power system static synchronous stability security region fast solution method.

[0028] Those skilled in the art can clearly understand that for the convenience and conciseness of description, the specific working process and related descriptions of the above-described electronic device and computer-readable storage medium can refer to the corresponding process in the foregoing method embodiments, and will not be repeated here.

[0029] Those skilled in the art should be able to realize that the modules and method steps of each example described in combination with the embodiments disclosed herein can be implemented by electronic hardware, computer software, or a combination of the two. The programs corresponding to the software modules and method steps can be placed in a random access memory (RAM), internal memory, read-only memory (ROM), electrically programmable ROM, electrically erasable programmable ROM, registers, hard disk, removable disk, CD-ROM, or any other form of storage medium well-known in the technical field. To clearly illustrate the interchangeability of electronic hardware and software, the composition and steps of each example have been generally described according to functions in the above description. Whether these functions are executed in the form of electronic hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered to exceed the scope of the present invention.

[0030] The terms "first", "second", etc. are used to distinguish similar objects, rather than to describe or represent a specific order or sequence.

[0031] The term "comprising" or any other similar term is intended to cover non-exclusive inclusion, so that a process, method, article, or device / apparatus comprising a series of elements includes not only those elements but also other elements not explicitly listed, or also elements inherent in these processes, methods, articles, or devices / apparatuses.

[0032] So far, the technical solution of the present invention has been described in combination with the preferred embodiments shown in the drawings. However, it is easy for those skilled in the art to understand that the protection scope of the present invention is obviously not limited to these specific embodiments. Without departing from the principle of the present invention, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will fall within the protection scope of the present invention.

Claims

1. A new method for quickly solving the static synchronous stability safety region of a power system, characterized by: The method comprises the following steps: Step S1: obtaining steady-state operation data of the power system as input data; based on the input data, calculating the equivalent impedance of the power grid, and then obtaining the attenuation coefficient of the state of the power system; the steady-state operation data includes the voltage, current, and power of each node; The attenuation coefficient is calculated as follows: Step S11, constructing a node voltage equation according to the node type of the power system and in combination with the input data; the node types include generator set nodes, tie nodes and load nodes; Step S12, constructing a node power equation; Step S13, combining the node voltage equation and the node power equation to obtain the relationship between the generator node voltage and current; Step S14, selecting the balancing node as an equivalent infinite power grid unit, and calculating the equivalent impedance according to the relationship between the voltage and current of the generator node; Step S15, calculating the attenuation coefficient in combination with the equivalent impedance; Step S2: In combination with the attenuation coefficient, a prediction correction method is used to calculate the static synchronous stability safety region of the power system.

2. The novel method for rapidly solving the static synchronous stability safety region of a power system according to claim 1 is characterized in that: The equivalent impedance is: ； In the formula, To balance the node unit voltage, U G,i For the generator node i The voltage phasor, b ik is the first i Line k Column elements, U G,k For the generator node k The voltage phasor.

3. The novel method for rapidly solving the static synchronous stability safety region of a power system according to claim 2 is characterized in that: The equivalent transfer function is calculated according to the equivalent impedance, and the equivalent transfer function is: ； In the formula, K (s) is the equivalent transfer letter, E is the identity matrix, Y inv is the converter output impedance array, Z g,i is the equivalent impedance.

4. The novel method for rapidly solving the static synchronous stability safety region of a power system according to claim 1 is characterized in that: The attenuation coefficient is: ； ； Where: p ki is the modulus of the residue, Res[K(s), p i ] for p i The number of residues at .

5. The novel method for rapidly solving the static synchronous stability safety region of a power system according to claim 1 is characterized in that: The method of using the prediction and correction method to calculate the static synchronous stability security region of the power system is: S31, obtaining the nodes in the power system a The boundary points of the single-direction power conversion direction are calculated to obtain the boundary point set of the single-direction power conversion direction N s， As the first collection; S32, let k=1, d=1, take the running solution of any boundary point of the power conversion direction in a single direction in the first set as the search starting point, and take the other boundary points of the first set except the search starting point as the search end points in sequence; The subscript of the search end point is greater than the subscript of the search start point; k is the number of iterations of the calculation; S33, calculating a predicted solution based on the value of the search starting point and the value of the search end point according to a predicted solution solving method; S34, calculating a correction direction in combination with the predicted solution; S35, combining the predicted solution and the correction direction, constructing a critical point search model and solving it, thereby obtaining a correction solution; S36, obtaining whether there is a case where the element in the correction solution is less than 0, if so, completing the safety domain boundary search between the search starting point and the search end point, and setting d=d+1, jumping to S37, otherwise, k=k+1, jumping to S34; d represents the number of newly added sets; S37, adding the correction solution to the new set N s,d As the second set, and determine whether the first set is traversed to P M-1 0 and P M 0 Boundary point, M is the number of generator nodes, if yes, jump to S38, otherwise jump to S34; S38, by gradually expanding the second set as a search starting point and a search end point; the second set is a new set in which the correction solution is sequentially stacked; S39, based on the re-determined search starting point and search end point, execute S33-S35 to obtain a corrected solution, and determine whether any element in the corrected solution is less than 0. If so, complete the search for the safety zone boundary between the search starting point and the search end point, and jump to S40; if not, return to step S38; S40, determine whether the last item in the second set has been traversed. If so, connect all boundary points to form a security domain boundary. If not, return to step S38 until the last item in the second set has been traversed and no new set is generated.

6. The novel method for rapidly solving the static synchronous stability safety region of a power system according to claim 5 is characterized in that: The predicted solution is calculated as follows: ； ； Where: represents the predicted solution obtained by the k-th iterative calculation between the a direction and the a+1 direction; k Calculate the number of iterations; For the k The predicted step length of the step; Represents the boundary point of a single change in direction; Represents the boundary point of a single change in the a+1 direction; represents the predicted solution obtained by the k-1th iterative calculation between the a direction and the a+1 direction; Defining Equivalence Factors Reflection Node i and nodes j Active power change to node q The voltage amplitude is affected, that is: ； In the formula, i and j is a numeric variable, right Equivalence coefficients for nodal analysis, i for , j for , q is , Indicates the change in active power of node i, Represents the change in active power of node j.

7. The novel method for rapidly solving the static synchronous stability safety region of a power system according to claim 5 is characterized in that: Calculate the correction direction , the method is: ； Where: For the k The predicted solution obtained by calculation is For the k The modulus of the predicted solution calculated this time.

8. The novel method for rapidly solving the static synchronous stability safety region of a power system according to claim 5 is characterized in that: The critical point search model is: ； Where: x represents the node voltage vector of the system; y represents the power vector injected into the system; f(x,y) is the AC system power flow equation; and are the upper and lower limits of the voltage amplitude of node i respectively; and are the upper and lower limits of the active power value allowed to be changed for node i respectively; and are the upper and lower limits of the reactive power value allowed to be changed at node i respectively; N a is the node set of the photovoltaic system; β a ref is the maximum value of the attenuation coefficient allowed under stable conditions; sgn() is the sign function.

9. The novel method for rapidly solving the static synchronous stability safety region of a power system according to claim 5 is characterized in that: Calibrated solution , which is calculated as: ； In the formula, is the correction step size of the kth step.

10. A new type of power system static synchronous stability safety region fast solution system, based on the new type of power system static synchronous stability safety region fast solution method according to any one of claims 1 to 9, characterized in that: include: Static synchronous stability margin quantification module, static synchronous stability safety domain fast solution module; The static synchronous stability margin quantification module is configured to obtain steady-state operation data of the power system as input data; based on the input data, calculate the equivalent impedance of the power grid, and then obtain the attenuation coefficient of the state of the power system; The steady-state operation data includes the voltage, current and power of each node; The static synchronous stability safety region fast solution module is configured to calculate the static synchronous stability safety region of the power system by using a prediction and correction method in combination with the attenuation coefficient.

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