A method and system for analyzing the operational stability of a multi-machine power system based on pumped storage and wind power interconnection

Abstract

The present invention belongs to the technical field related to power system stability analysis and discloses a method and system for analyzing the operational stability of a multi-machine power system based on pumped storage and wind power interconnection. The method includes the following steps: applying electromagnetic power disturbances to synchronous generator sets in the multi-machine power system and performing time-domain simulation to obtain electromagnetic power vectors and reference electromagnetic power vectors for each synchronous generator set, pumped storage unit, and wind generator set during the simulation process; using the electromagnetic power vectors and reference electromagnetic power vectors to calculate the stability index of each synchronous generator set, pumped storage unit, and wind generator set, respectively, and using these to calculate the stability index of the multi-machine power system. The present invention solves the problem in the prior art of being unable to analyze the stability of a multi-machine power system.

Description

Technical Field

[0001] The present invention belongs to the technical field related to power system stability analysis, and more specifically, relates to a method and system for analyzing the operational stability of a multi-machine power system based on pumped storage wind power interconnection. Background Art

[0002] Pumped-storage power stations, as large-scale, well-regulated flexible energy storage devices, play a vital role in shifting peak loads and facilitating the integration of renewable energy. Combining pumped storage and wind power generation can leverage the complementary advantages of power generation and has significant application prospects in multi-machine power systems. To mitigate fluctuations in wind power output, pumped-storage units frequently change their operating conditions, leading to risks such as hydraulic vibration, power oscillation, and frequency overruns. The interconnection of large-scale pumped-storage and wind power generation poses both a threat and a challenge to the safe and stable operation of multi-machine power systems, making research on their operational stability essential.

[0003] However, existing research on interconnected pumped-storage wind farms primarily focuses on single-machine infinite-scale systems and has yet to consider the operational characteristics of multi-machine power systems. The mechanisms by which interconnected pumped-storage wind farms at different node locations impact the operational stability of multi-machine power systems remain unexplained, and small-signal theory and metrics have limitations in assessing system stability. Currently, there is no reliable comprehensive stability assessment metric to quantitatively assess power system operational stability. Therefore, a method for analyzing the operational stability of multi-machine power systems based on interconnected pumped-storage wind farms is urgently needed to address these issues. Summary of the Invention

[0004] In response to the above defects or improvement needs of the existing technology, the present invention provides a method and system for analyzing the operational stability of a multi-machine power system based on pumped storage wind power interconnection, which solves the problem that the existing technology cannot analyze the stability of a multi-machine power system.

[0005] To achieve the above objectives, according to one aspect of the present invention, a method for analyzing the operational stability of a multi-machine power system based on pumped storage and wind power interconnection is provided, the method comprising the following steps:

[0006] After applying electromagnetic power disturbances to the synchronous generator sets in the multi-machine power system, time-domain simulation is performed to obtain the electromagnetic power vectors and reference electromagnetic power vectors of each synchronous generator set, pumped storage unit, and wind turbine generator set during the simulation process.

[0007] The electromagnetic power vector and the reference electromagnetic power vector are used to calculate the stability index of each synchronous generator set, pumped storage unit and wind generator set respectively, and the stability index of the multi-machine power system is calculated based on the stability index.

[0008] Further preferably, the calculation relationship of the stability index of the multi-machine power system is as follows:

[0009]

[0010] Among them, S T is the overall stability index of the multi-machine power system; S ti is the stability index of the synchronous generator set in the i-th region (i = 1 to x), x is the total number of synchronous generator sets in the multi-machine power system; S tPSPS is the stability index of the pumped storage unit; S tWPS It is the stability index of wind turbine.

[0011] Further preferably, the calculation relationship of the stability index of the synchronous generator set is as follows:

[0012] S ti =∫P ei -P ei0 dt

[0013] Where t is the time domain simulation time; P ei is the electromagnetic power vector of the synchronous generator set in the i-th region (i=1~x) in the time domain simulation; P ei0 is the reference electromagnetic power vector of the synchronous generator set in the i-th region (i=1~x) in the time domain simulation.

[0014] Further preferably, the calculation relationship of the stability index of the pumped storage unit is as follows:

[0015] S tPSPS =∫P ePSPS -P ePSPS0 dt

[0016] Among them, P ePSPS is the electromagnetic power vector of the pumped storage unit in time domain simulation; P ePSPS0 is the reference electromagnetic power vector of the pumped storage unit in time domain simulation.

[0017] Further preferably, the calculation relationship of the stability index of the wind turbine generator set is as follows:

[0018] S tWPS =∫P eWPS -P eWPS0 dt

[0019] Among them, P eWPS is the electromagnetic power vector of the wind turbine in time domain simulation; P eWPS0 is the reference electromagnetic power vector of the wind turbine in time domain simulation.

[0020] According to another aspect of the present invention, a multi-machine power system based on pumped storage wind power interconnection is provided, the system comprising a synchronous generator module and a pumped storage wind power interconnection module, wherein:

[0021] The synchronous generator set module includes a plurality of synchronous generator sets connected to each other;

[0022] The pumped storage wind power interconnection module includes a pumped storage unit, a wind power generation unit and a transmission line unit. The pumped storage unit is used to convert the gravitational potential energy of the water flow into kinetic energy for the turbine to rotate and generate electricity; the wind power generation unit is used to convert wind resources into kinetic energy for the shaft system to rotate and generate electricity, and the transmission line unit is used to connect the pumped storage unit and the wind power generator set to the common bus of the synchronous generator set module.

[0023] Further preferably, the pumped storage unit includes an upper reservoir, a penstock, a pumped storage unit and a lower reservoir connected in sequence; the wind turbine unit includes a shaft system, a wind turbine unit and an inverter connected in sequence.

[0024] According to another aspect of the present invention, a system for analyzing the operational stability of a multi-machine power system based on pumped storage and wind power interconnection is provided. The system includes a simulation module, a monitoring module, and a stability analysis module, wherein:

[0025] The simulation module is used to perform time domain simulation on a multi-machine power system;

[0026] The monitoring module is used to monitor the electromagnetic power vector and the reference electromagnetic power vector of each synchronous generator set, pumped storage generator set and wind generator set in the multi-machine power system during the simulation process;

[0027] The stability analysis module is used to calculate the stability index of each synchronous generator set, pumped storage unit and wind turbine generator set and the stability index of the multi-machine power system respectively.

[0028] According to another aspect of the present invention, a multi-machine power system operation stability analysis system based on pumped storage wind power interconnection is provided, which includes an actuator for executing the above-mentioned multi-machine power system operation stability analysis method based on pumped storage wind power interconnection.

[0029] According to another aspect of the present invention, a computer-readable storage medium is provided, on which a computer program is stored. When the computer program is executed by a processor, the above-mentioned method for analyzing the operational stability of a multi-machine power system based on pumped storage and wind power interconnection is implemented.

[0030] In general, the above technical solutions conceived by the present invention have the following beneficial effects compared with the prior art:

[0031] 1. The operational stability analysis method proposed in this invention overcomes the defect that previous power system stability analysis research was limited to single-machine infinite power systems and difficult to expand to multi-machine power systems. In the past, the stability index of a single-machine infinite system needed to be obtained through frequency domain calculation. The calculation process was complex and inefficient, making it difficult to extend to the stability analysis of a multi-machine power system. However, the proposed operational stability index calculation method is obtained through time domain simulation. The electromagnetic power vectors of the units in each power generation area can be easily obtained through the power station monitoring system. The operational stability index calculation is simple and easy to operate, significantly improving the accuracy and efficiency of the stability assessment of a multi-machine power system interconnected by pumped storage and wind power.

[0032] 2. The operational stability index of the present invention can truly reflect the operational stability of the multi-machine power system of the pumped storage wind power interconnection, avoid the derivation of the complex state matrix of the multi-machine power system of the pumped storage wind power interconnection and the solution of high-order eigenvalues, effectively save computer computing time, and have good portability.

[0033] 3. The operational stability index proposed in this invention is a comprehensive stability evaluation index that takes into account the stability performance of units in each power generation area of ​​a multi-machine power system of pumped storage wind power interconnection. It is suitable for studying the grid-connected location and capacity configuration rules of pumped storage wind power interconnection, and can provide reliable suggestions for the safe and stable operation of actual pumped storage wind power interconnection grid connection.

[0034] 4. The stability analysis and evaluation method for a multi-machine power system of a pumped storage wind power interconnection proposed in the present invention uses the rule that the smaller the operational stability index, the better to judge the overall system operational stability. It can avoid scenarios with large operational stability indicators in advance, effectively improve the damping performance of the pumped storage wind power interconnection grid-connected system, and maximize the solution to the low-frequency oscillation problem existing in the multi-machine power system. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 This is a flow chart of a method for analyzing the operational stability of a multi-machine power system based on pumped storage and wind power interconnection constructed according to a preferred embodiment of the present invention;

[0036] Figure 2 This is a structural diagram of a pumped storage wind power interconnection system constructed according to a preferred embodiment of the present invention being incorporated into a multi-machine power system at the second common bus 7;

[0037] Figure 3 This is an electromagnetic power vector diagram of the first synchronous generator set in a time-domain simulation of a multi-machine power system in which the first common bus 4, the second common bus 7, and the third common bus 9 of the pumped storage wind power interconnection system constructed according to the preferred embodiment of the present invention are incorporated;

[0038] Figure 4This is an electromagnetic power vector diagram of the second synchronous generator set in a time-domain simulation of a multi-machine power system in which the first common bus 4, the second common bus 7, and the third common bus 9 of the pumped storage wind power interconnection system constructed according to the preferred embodiment of the present invention are incorporated;

[0039] Figure 5 This is an electromagnetic power vector diagram of the third synchronous generator set in a time-domain simulation of a multi-machine power system in which the first common bus 4, the second common bus 7, and the third common bus 9 of the pumped storage wind power interconnection system constructed according to the preferred embodiment of the present invention are incorporated;

[0040] Figure 6 This is an electromagnetic power vector diagram of a pumped-storage unit in a time-domain simulation of a multi-machine power system in which the first common bus 4, the second common bus 7, and the third common bus 9 of the pumped-storage wind power interconnection system constructed according to a preferred embodiment of the present invention are incorporated;

[0041] Figure 7 This is an electromagnetic power vector diagram of a wind turbine generator set in a time-domain simulation of a multi-machine power system in which the first common bus 4, the second common bus 7, and the third common bus 9 of a pumped storage wind power interconnection system constructed according to a preferred embodiment of the present invention are incorporated;

[0042] Figure 8 It is a stacked bar chart of the operational stability indicators of each power generation area in the time domain simulation of the multi-machine power system in which the first common bus 4, the second common bus 7 and the third common bus 9 of the pumped storage wind power interconnection system constructed according to the preferred embodiment of the present invention are incorporated.

[0043] Throughout the drawings, the same reference numerals are used to denote the same elements or structures, wherein:

[0044] 1-first generator bus, 2-second generator bus, 3-third generator bus, 4-first common bus, 5-first load bus, 6-second load bus, 7-second common bus, 8-third load bus, 9-third common bus, 10-fourth generator bus. DETAILED DESCRIPTION

[0045] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely for the purpose of explaining the present invention and are not intended to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.

[0046] A multi-machine power system based on pumped storage and wind power interconnection includes a synchronous generator module and a pumped storage and wind power interconnection module. The synchronous generator module includes multiple interconnected synchronous generators. The pumped storage unit is used to convert the gravitational potential energy of water flow into kinetic energy for turbine rotation and power generation; the wind power generation unit is used to convert wind resources into kinetic energy for shaft rotation and power generation; and the transmission line unit is used to connect the pumped storage unit and wind power generator to the common busbar of the synchronous generator module. The pumped storage unit includes an upper reservoir, a penstock, a pumped storage unit, and a lower reservoir connected in sequence; the wind power generator unit includes a shaft system, a wind power generator, and an inverter connected in sequence.

[0047] Specifically, the constructed pumped storage wind power interconnection system is planned to be integrated into the multi-machine power system at the second common bus 7 .

[0048] In one embodiment of the present invention, a multi-machine power system interconnected by pumped storage and wind power includes three regions of synchronous generator sets, namely the first synchronous generator set, the second synchronous generator set and the third synchronous generator set, one region of pumped storage units and wind turbine generator sets, and the buses connected to the power system include the first generator bus 1, the second generator bus 2, the third generator bus 3, the first common bus 4, the first load bus 5, the second load bus 6, the second common bus 7, the third load bus 8, the third common bus 9, and the fourth generator bus 10. The topology of the multi-machine power system interconnected by pumped storage and wind power is as follows: Figure 2 shown.

[0049] The embodiment of the present invention provides a method for analyzing the operational stability of a multi-machine power system based on pumped storage wind power interconnection. Figure 1 shown.

[0050] (1) A small disturbance fault is imposed on a multi-machine power system interconnected with pumped storage and wind power, and a time domain simulation is performed for a period of time after the fault is cleared.

[0051] In one embodiment of the present invention, a small disturbance fault is applied to the first synchronous generator set (any synchronous generator set), with a 0.1 pu electromagnetic power step-down disturbance. The fault is cleared after 0.1 s, and a time domain simulation of the multi-machine power system is carried out for 10 s.

[0052] In one embodiment of the present invention, the time domain simulation solves the state variable equations of the multi-machine power system of the pumped storage wind power interconnection by using the ode15s function of MATLAB.

[0053] (2) Obtain the electromagnetic power vector and reference electromagnetic power vector of each generator set in the multi-machine power system of pumped storage and wind power interconnection in time domain simulation.

[0054] In one embodiment of the present invention, the electromagnetic power vector and reference electromagnetic power vector of each generator set in the multi-machine power system of the pumped storage wind power interconnection obtained in the time domain simulation are defined as follows: The electromagnetic power vector and reference electromagnetic power vector of the synchronous generator set in the i-th region (i=1~x) in the time domain simulation are defined as P ei and P ei0 , define the electromagnetic power vector of the pumped storage unit and the reference electromagnetic power vector in the time domain simulation as P ePSPS and P ePSPS0 , define the electromagnetic power vector of the wind turbine generator set and the reference electromagnetic power vector in the time domain simulation as P eWPS and P eWPS0 .

[0055] In one embodiment of the present invention, the grid connection position of the pumped storage wind power interconnection system is changed so that it is connected to the multi-machine power system at the first common bus 4, the second common bus 7, and the third common bus 9. The electromagnetic power vectors of each power generation area in the time domain simulation of the pumped storage wind power interconnection system being connected to the multi-machine power system at the first common bus 4, the second common bus 7, and the third common bus 9 are as follows: Figure 3-7 shown.

[0056] See Figure 3-7 It can be seen that after a small disturbance fault is applied to the first synchronous generator set, the electromagnetic power vector oscillation amplitude of each generating area gradually decreases and quickly converges to a stable state through the internal controller of the pumped-storage wind power interconnected multi-machine power system. This shows that the pumped-storage wind power interconnected system is small-signal stable when integrated into the multi-machine power system at the second common bus 7. It can quickly recover to a balanced state after a small disturbance fault and has good performance in damping low-frequency oscillations.

[0057] Regarding the dynamic responses of various power generation areas, grid connection of the pumped-storage wind power interconnection system to the first common busbar 4 results in the lowest oscillation amplitude for the first synchronous generator set, pumped-storage unit, and wind turbine set. However, grid connection to the second common busbar 7 results in more intense low-frequency oscillations, indicating that grid connection to the first common busbar 4 significantly improves the damping performance of the first synchronous generator set, pumped-storage unit, and wind turbine set against low-frequency oscillations. The dynamic responses of the second and third synchronous generator sets exhibit complex variations. Overall, grid connection to the first common busbar 4 results in larger oscillation amplitude for the second synchronous generator set in the early stages, but rapid convergence to equilibrium in the later stages. However, grid connection to the second common busbar 7 results in a lower oscillation attenuation rate. Grid connection to the first common busbar 4 results in the largest oscillation amplitude for the third synchronous generator set, with a gradual decrease in damping performance, indicating that integrating pumped-storage wind power interconnection into a multi-machine power system can weaken the stability of certain power generation areas. After comprehensive consideration, it can be seen that the optimal location for integrating pumped storage wind power into the multi-machine power system is the first common bus 4, and the operating stability and damping characteristics of each power generation area and the overall system are significantly improved.

[0058] (3) Carry out calculation of operational stability indicators for each power generation area and the entire multi-machine power system interconnected by pumped storage and wind power.

[0059] Furthermore, the calculation method of the operation stability index of each power generation area is as follows:

[0060] The operating stability index S of the synchronous generator set in the i-th region (i=1~x) ti The calculation method is

[0061] S ti =∫P ei -P ei0 dt

[0062] Where t is the time domain simulation time, in seconds.

[0063] Operation stability index S of pumped storage unit tPSPS The calculation method is

[0064] S tPSPS =∫P ePSPS -P ePSPS0 dt

[0065] Wind turbine operating stability index S tWPS The calculation method is

[0066] S tWPS =∫P eWPS -P eWPS0 dt

[0067] Furthermore, the overall operational stability index S of the multi-machine power system interconnected by pumped storage and wind power is T The calculation method is:

[0068]

[0069] In one embodiment of the present invention, according to the calculation method of the operation stability index of each power generation area, the pumped storage wind power interconnection system is incorporated into the multi-machine power system at the first common bus 4 of the generator, and the operation stability index S of the first synchronous generator set is t1 is 34.7535, and the operating stability index S of the second synchronous generator set is t2 is 22.7632, and the operating stability index S of the third synchronous generator set is t3 is 6.9927, and the operating stability index S of the pumped storage unit is tPSPS The operating stability index S of the wind turbine is 21.1091. tWPS It is 2.3674.

[0070] According to the calculation method of the operation stability index of each power generation area, the pumped storage wind power interconnection system is integrated into the multi-machine power system at the second common bus 7 of the generator, and the operation stability index S of the first synchronous generator set is t1 is 56.5711, and the operating stability index S of the second synchronous generator set is t2 The operating stability index S of the third synchronous generator set is 17.8042. t3 is 5.5270, and the operating stability index S of the pumped storage unit tPSPS is 36.2178, and the wind turbine operation stability index S tWPS It is 4.9994.

[0071] According to the calculation method of the operation stability index of each power generation area, the pumped storage wind power interconnection system is integrated into the multi-machine power system at the third common bus 9 of the generator, and the operation stability index S of the first synchronous generator set is: t1 is 47.3777, and the operating stability index S of the second synchronous generator set is t2 is 18.0915, and the operating stability index S of the third synchronous generator set is t3 is 6.0126, and the operating stability index S of the pumped storage unit tPSPS is 32.2763, and the operating stability index S of the wind turbine generator set is tWPS It is 4.1081.

[0072] According to the overall operational stability index S of the multi-machine power system interconnected by pumped storage and wind power TThe calculation method shows that the pumped storage wind power interconnection system is connected to the multi-machine power system when the first common bus 4, the second common bus 7 and the third common bus 9 of the generator are integrated into the S T They are 87.9859, 121.1194 and 107.8662 respectively.

[0073] (4) Analyze and evaluate the operational stability of each power generation area and the overall multi-machine power system of the pumped storage wind power interconnection.

[0074] Furthermore, the operational stability analysis and evaluation method of each power generation area of ​​the multi-machine power system of pumped storage wind power interconnection is as follows: ti Analyze and evaluate the operational stability of synchronous generators in the i-th region (i=1~x), S ti The smaller it is, the stronger the operating stability of the synchronous generator set in the i-th region is. tPSPS Analyze and evaluate the operational stability of pumped storage units, S tPSPS The smaller it is, the stronger the operating stability of the pumped storage unit is. tWPS Analyze and evaluate the operational stability of wind turbines, S tWPS The smaller it is, the more stable the wind turbine operation is.

[0075] In one embodiment of the present invention, a stacked bar chart is drawn based on the operational stability index of each power generation area of ​​a multi-machine power system interconnected by pumped storage and wind power, such as Figure 8 shown.

[0076] See Figure 8 It can be seen that the height of the stacked bar charts of the operational stability indicators for each generating area of ​​the pumped-storage wind power interconnected multi-machine power system exactly corresponds to the overall operational stability indicator value, allowing for a clear analysis and assessment of the operational stability of each generating area and the entire system. Among them, the first common busbar 4 has the smallest stacked bar height, followed by the third common busbar 9, and the second common busbar 7 has the highest. This indicates that the optimal grid-connected location for the pumped-storage wind power interconnection into the multi-machine power system is the first common busbar 4. The calculated operational stability indicators for each generating area are consistent with the time-domain simulation results, verifying the accuracy of the proposed operational stability indicators. Comparing the electromagnetic power oscillations of each generating area, the first synchronous generator unit has the largest area. This is primarily due to the small signal perturbation being applied to the first synchronous generator unit, resulting in a greater impact on the electromagnetic power after the perturbation of the first synchronous generator unit, which is closer to the fault point. Furthermore, the pumped-storage units are significantly affected by the fault perturbation, exhibiting larger bar chart areas. This is primarily due to the pumped-storage power station acting as a regulator, providing rapid feedback control of the grid-connected system load perturbation, thereby suppressing the propagation of low-frequency oscillations.

[0077] Furthermore, the overall operational stability analysis and evaluation method of the multi-machine power system interconnected by pumped storage and wind power is based on ST Analyze and evaluate the overall operational stability of the multi-machine power system interconnected by pumped storage and wind power, S T The smaller it is, the stronger the overall operational stability of the pumped storage wind power interconnection integrated into the multi-machine power system.

[0078] Furthermore, the pumped storage wind power interconnection system is compared with the S system in which the first common bus 4, the second common bus 7 and the third common bus 9 are integrated into the multi-machine power system. T It can be seen that when the first common busbar 4 is connected to the grid, S T The minimum value indicates that the pumped-storage wind power interconnection system has the highest operational stability when connected to the multi-machine power system at the first common busbar 4. In actual grid-connected operation, it is recommended that the pumped-storage wind power interconnection system be connected to the first common busbar 4. This can significantly improve the low-frequency oscillation phenomenon in the multi-machine power system, enhance the overall system damping performance, and improve the dynamic regulation quality of the units in each generating area.

[0079] It will be easily understood by those skilled in the art that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A method for analyzing the operational stability of a multi-machine power system based on pumped storage and wind power interconnection, characterized in that: The method comprises the following steps: After applying electromagnetic power disturbances to the synchronous generator sets in the multi-machine power system, time-domain simulation is performed to obtain the electromagnetic power vectors and reference electromagnetic power vectors of each synchronous generator set, pumped storage unit, and wind turbine generator set during the simulation process. Calculating the stability index of each synchronous generator set, pumped storage unit and wind turbine generator set respectively using the electromagnetic power vector and the reference electromagnetic power vector, and calculating the stability index of the multi-machine power system based on the stability index; The calculation relationship of the stability index of the multi-machine power system is as follows: in, S T It is the overall stability index of the multi-machine power system; S ti For the i Regions ( i =1~ x ) Stability index of synchronous generator sets, x is the total number of synchronous generator sets in the multi-machine power system; S tPSPS It is the stability index of the pumped storage unit; S tWPS It is the stability index of wind turbine generator set; The calculation relationship of the stability index of the synchronous generator set is as follows: in, t is the time domain simulation time; P ei For the time domain simulation i Regions ( i =1~ x ) of the synchronous generator set electromagnetic power vector; P ei0 For the time domain simulation i Regions ( i =1~ x ) of the synchronous generator set reference electromagnetic power vector; The calculation relationship of the stability index of the pumped storage unit is as follows: in, P ePSPS is the electromagnetic power vector of the pumped storage unit in time domain simulation; P ePSPS0 is the reference electromagnetic power vector of the pumped storage unit in time domain simulation; The calculation relationship of the stability index of the wind turbine generator set is as follows: in, P eWPS is the electromagnetic power vector of the wind turbine in the time domain simulation; P eWPS0 is the reference electromagnetic power vector of the wind turbine in time domain simulation.

2. A multi-machine power system that uses the method for analyzing the operation stability of a multi-machine power system based on pumped storage and wind power interconnection according to claim 1 for stability analysis, characterized in that: The system includes a synchronous generator module and a pumped storage wind power interconnection module, where: The synchronous generator set module includes a plurality of synchronous generator sets connected to each other; The pumped storage wind power interconnection module includes a pumped storage unit, a wind power generation unit and a transmission line unit. The pumped storage unit is used to convert the gravitational potential energy of the water flow into kinetic energy for the turbine to rotate and generate electricity; the wind power generation unit is used to convert wind resources into kinetic energy for the shaft system to rotate and generate electricity, and the transmission line unit is used to connect the pumped storage unit and the wind power generator set to the common bus of the synchronous generator set module.

3. The method for analyzing the operational stability of a multi-machine power system based on pumped storage and wind power interconnection according to claim 2, characterized in that: The pumped storage unit includes an upper reservoir, a pressure steel pipe, a pumped storage unit and a lower reservoir connected in sequence; the wind power generation unit includes a shaft system, a wind power generator set and an inverter connected in sequence.

4. A system for analyzing the operational stability of a multi-machine power system based on pumped storage wind power interconnection, which performs stability analysis using the method for analyzing the operational stability of a multi-machine power system based on pumped storage wind power interconnection according to claim 1, characterized in that: The system includes simulation module, monitoring module and stability analysis module, among which: The simulation module is used to perform time domain simulation on a multi-machine power system; The monitoring module is used to monitor the electromagnetic power vector and the reference electromagnetic power vector of each synchronous generator set, pumped storage generator set and wind generator set in the multi-machine power system during the simulation process; The stability analysis module is used to calculate the stability index of each synchronous generator set, pumped storage unit and wind turbine generator set and the stability index of the multi-machine power system respectively.

5. A multi-machine power system operation stability analysis system based on pumped storage wind power interconnection, characterized in that: The system includes an actuator, which is used to execute the method for analyzing the operational stability of a multi-machine power system based on pumped storage and wind power interconnection as described in claim 1.

6. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the method for analyzing the operational stability of a multi-machine power system based on pumped storage and wind power interconnection as described in claim 1 is implemented.

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