A method and system for tuning transient stability damping parameters of a multi-virtual synchronous grid power system
By using an EEAC-based clustering method and differentiated damping adjustment, the transient instability problem of multi-virtual synchronous grid power systems under large disturbances was solved, thus improving the transient stability of the system.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- STATE GRID ELECTRIC POWER RES INST
- Filing Date
- 2026-01-19
- Publication Date
- 2026-05-26
Smart Images
Figure CN122092231A_ABST
Abstract
Description
Technical Field
[0001] This application relates to a method and system for tuning transient stability damping parameters in a multi-virtual synchronous grid power system, belonging to the field of power system automation technology. Background Technology
[0002] Grid-type converters, represented by virtual synchronous generators (VSGs), provide virtual inertia and damping support for the system by simulating the rotor motion equations of synchronous machines, and have become an important technical means for the stable operation of the system in the context of high proportion of new energy access.
[0003] However, similar to traditional synchronous generator systems, multi-grid converter systems also face synchronization stability problems due to inter-unit power angle instability after large disturbances. Existing research generally shows that the damping coefficient of the virtual synchronous machine has a significant impact on the system's synchronization stability. Against this backdrop, the unique advantage of the virtual synchronous machine compared to traditional synchronous generators—its flexible and adjustable parameters—creates favorable conditions for in-depth exploration of damping variation laws and improvement of system synchronization stability. However, existing literature on the adjustment characteristics of damping parameters in multi-virtual synchronous grid power systems is still not systematic enough, especially regarding the insufficient understanding of damping adjustment laws under different operating conditions, which restricts further improvement in the system's transient stability level.
[0004] Therefore, systematically exploring the variation characteristics and laws of damping in multi-virtual synchronous grid power systems is of great significance for improving system stability. Summary of the Invention
[0005] Objective: In view of at least one of the above technical problems, this application provides a method and system for tuning transient stability damping parameters of a multi-virtual synchronous generator system when encountering large disturbances such as line faults, in order to make full use of the advantages of flexible and adjustable virtual synchronous generator parameters. Based on the disturbed trajectory of the virtual synchronous generator, the system is dynamically grouped based on EEAC, and differentiated damping adjustment strategies are implemented for the leading group and the remaining groups, thereby suppressing the power angle swing among the multi-virtual synchronous generators and improving the transient stability performance of the system.
[0006] The technical solution adopted in this application is:
[0007] Firstly, this application provides a method for tuning transient stability damping parameters of a multi-virtual synchronous grid power system, including:
[0008] In response to the detection of a line fault, the disturbed electromechanical transient trajectories of each virtual synchronizer in a multi-virtual synchronous network power system are acquired;
[0009] Based on the disturbed electromechanical transient trajectory, each virtual synchronous machine in the multi-virtual synchronous grid power system is divided into a leading group and a remaining group.
[0010] For the virtual synchronizer in the leading group, increase the virtual damping of the virtual synchronizer;
[0011] For the virtual synchronizers in the remaining group, if the virtual synchronizer in the remaining group is in an accelerating state during the system acceleration phase, then the virtual damping of the virtual synchronizer is reduced; if the virtual synchronizer in the remaining group is in a decelerating state during the system acceleration phase, then the virtual damping of the virtual synchronizer is increased.
[0012] Secondly, this application provides a transient stability damping parameter tuning device for a multi-virtual synchronous grid power system, comprising:
[0013] The acquisition module is used to: in response to the detection of a line fault, acquire the disturbed electromechanical transient trajectories of each virtual synchronous machine in a multi-virtual synchronous network power system;
[0014] The partitioning module is used to: based on the disturbed electromechanical transient trajectory, divide each virtual synchronous machine in the multi-virtual synchronous network power system into a leading group and a remaining group;
[0015] The adjustment module is used to: increase the virtual damping of the virtual synchronizer in the leading group; decrease the virtual damping of the virtual synchronizer in the remaining group if the virtual synchronizer in the remaining group is in an accelerating state during the system acceleration phase; and increase the virtual damping of the virtual synchronizer in the remaining group if the virtual synchronizer in the remaining group is in a decelerating state during the system acceleration phase.
[0016] Thirdly, this application provides a transient stability damping parameter tuning system for a multi-virtual synchronous grid power system, including a processor and a storage medium;
[0017] The storage medium is used to store instructions;
[0018] The processor is configured to operate according to the instructions to execute the method described in accordance with the first aspect.
[0019] Fourthly, this application provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the method described in the first aspect.
[0020] Fifthly, this application provides a computer device including a memory and a processor, wherein the memory stores a computer program, and the processor executes the computer program to implement the method described in the first aspect.
[0021] In a sixth aspect, this application provides a computer program product, including a computer program that, when executed by a processor, implements the method described in the first aspect.
[0022] Beneficial Effects: The transient stability damping parameter tuning method and system for multi-virtual synchronous grid power systems provided in this application have the following advantages: This application is a transient stability improvement method based on extended equal area criterion (EEAC) grouping and equivalent machine speed state identification. After detecting a line fault, the virtual synchronous machines (VSGs) in the system are divided into leading group and remaining group based on the disturbed trajectory of each virtual synchronous machine (VSG). If the speed of the remaining group increases during the fault acceleration phase, its damping is reduced; conversely, if the speed of the remaining group decreases during the fault acceleration phase, its damping is increased. For the leading group virtual synchronous machines, their damping is uniformly increased to suppress power angle expansion. This suppresses power angle oscillation among multi-virtual synchronous grid power sources and improves the transient stability performance of the system. Attached Figure Description
[0023] Figure 1 This is a schematic diagram of the VSG control structure in an embodiment of this application.
[0024] Figure 2 This is a schematic diagram of the VSG active power loop control principle in an embodiment of this application.
[0025] Figure 3 This is a three-machine, nine-node system used in the embodiments of this application to verify the validity of this application.
[0026] Figure 4 The remaining group speeds in this application embodiment are the power angles, speeds, and speeds of the three machines under the condition of increased speed of the remaining groups.
[0027] Figure 5 The remaining group speed reduction conditions in this application embodiment represent the power angle, speed of the three machines, and the speed of the two groups.
[0028] Figure 6 This is a phase plane diagram of different residual group damping during residual group acceleration in the embodiments of this application.
[0029] Figure 7 The figures show the power angle characteristic curves under different leading group damping in the embodiments of this application.
[0030] Figure 8 The figures show the power angle characteristic curves under different residual group damping conditions during residual group acceleration in the embodiments of this application.
[0031] Figure 9 The figures show the power angle characteristic curves under different residual group damping conditions during residual group acceleration in the embodiments of this application.
[0032] Figure 10This is a phase plane diagram of the remaining group under different remaining group damping during deceleration in the embodiments of this application.
[0033] Figure 11 The figures show the power angle characteristic curves under different damping of the remaining group during deceleration in the embodiments of this application. Detailed Implementation
[0034] The present application will be further described below with reference to the accompanying drawings and embodiments. The following embodiments are only used to more clearly illustrate the technical solutions of the present application, and should not be used to limit the scope of protection of the present application.
[0035] In the description of this application, "several" means one or more, "multiple" means two or more, "greater than," "less than," and "exceeding" are understood to exclude the stated number, while "above," "below," and "within" are understood to include the stated number. The use of "first" and "second" in the description is merely for distinguishing technical features and should not be construed as indicating or implying relative importance, or implicitly indicating the number of indicated technical features, or implicitly indicating the order of the indicated technical features.
[0036] In the description of this application, the terms "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.
[0037] The term "and / or" simply describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A alone, A and B simultaneously, or B alone. Additionally, the character " / " generally indicates that the preceding and following related objects have an "or" relationship.
[0038] To address the transient instability problem of multi-virtual synchronous generator systems under large disturbances such as line faults, and to fully utilize the flexible and adjustable parameters of virtual synchronous generators, a transient stability improvement method and system based on Extended Equal Area Criterion (EEAC) grouping and equivalent machine speed state identification is proposed. This application uses the disturbed trajectory of the virtual synchronous machine and the Extended Equal Area Criterion (EEAC) to dynamically group the system. Differential damping adjustment strategies are implemented for the leading group and the remaining groups, thereby suppressing the power angle swing among the power sources in the multi-virtual synchronous grid and improving the transient stability performance of the system.
[0039] Example 1: This example provides a method for tuning transient stability damping parameters of a multi-virtual synchronous grid-connected power system, such as... Figure 1 As shown, it includes:
[0040] S1: In response to the detection of a line fault, acquire the disturbed electromechanical transient trajectory of each virtual synchronous machine in the multi-virtual synchronous network power system.
[0041] In step S1, in the multi-virtual synchronous grid-connected power system, all grid-connected converters employ virtual synchronous control (the active power loop simulates the rotor motion equations of a traditional synchronous machine), such as... Figure 2 As shown, the active power control equation is:
[0042] ;
[0043] In the formula: J and D are virtual inertia and virtual damping, respectively; t is time; ω and ω0 are the actual and commanded values of the converter output angular frequency, respectively; P e and P ref These are the actual and commanded values of the active power output by the converter, respectively.
[0044] Dω0(ω-ω0) is the damping term of the grid-type converter, which is transformed into:
[0045] ;
[0046] In the formula: ω is the difference between the actual value ω and the commanded value ω0 of the converter output angular frequency, and δ is the virtual power angle of the grid-type converter, used to characterize the angle between the common coupling point voltage and the converter voltage.
[0047] In virtual synchronous control, the damping term not only performs primary frequency regulation but also suppresses oscillations. Its typical value is significantly higher than that of traditional synchronous generators, having a crucial impact on system transient stability. Therefore, the magnitude of the virtual damping term D plays a critical role in transient stability.
[0048] S2: Based on the disturbed electromechanical transient trajectory, each virtual synchronous machine in the multi-virtual synchronous grid power system is divided into a leading group and a remaining group.
[0049] In this embodiment, the grouping is based on the method of the extended equal area criterion EEAC, which is based on the shape of the work angle trajectory.
[0050] Further, in step S2, each virtual synchronizer in the multi-virtual synchronous grid power system is divided into a leading group and a remaining group, including:
[0051] At each sampling time, n disturbed electromechanical transient trajectories are projected onto a one-dimensional power angle axis and arranged in ascending order of value to generate n−1 adjacent gaps;
[0052] If a gap grows unbounded over time among n-1 adjacent gaps, it is determined to be an unbounded position gap (UPG).
[0053] In a multi-virtual synchronous grid power system, the virtual synchronous machines are divided into the leading group (S group) whose power angle is above the unbounded position gap and the remaining group (A group) whose power angle is below the unbounded position gap.
[0054] S3: For the virtual synchronizer in the leading group, increase the virtual damping of the virtual synchronizer;
[0055] S4: For the virtual synchronizers in the remaining group, if the virtual synchronizers in the remaining group are in an accelerating state during the system acceleration phase, then reduce the virtual damping of the virtual synchronizer; if the virtual synchronizers in the remaining group are in a decelerating state during the system acceleration phase, then increase the virtual damping of the virtual synchronizer.
[0056] Furthermore, in steps S3 and S4, increasing the virtual damping of the virtual synchronizer includes:
[0057] The adjustment of the virtual damping of the corresponding virtual synchronizer is obtained through comprehensive tuning via offline simulation analysis, based on the severity of disturbances that the multi-virtual synchronized grid power system can withstand (such as fault type, fault clearing time and duration). For example, the virtual damping D of the virtual synchronizer is adjusted from the initial value D0 to kD0, where k is the damping amplification factor, and k > 1.
[0058] Further, in step S4, reducing the virtual damping of the virtual synchronizer includes: adjusting the virtual damping D of the virtual synchronizer from the initial value D0 to mD0, where m is the damping reduction coefficient (0 < m < 1).
[0059] After adjusting the virtual damping D of the virtual synchronous machine, its power angle expansion trend can be effectively suppressed, thereby improving the synchronization stability of multi-virtual synchronous grid power systems.
[0060] It should be noted that a multi-virtual synchronous grid power system contains n virtual synchronous machines. Therefore, for any virtual synchronous machine, the rotor motion equation of the i-th virtual synchronous machine is:
[0061] ;
[0062] In the formula: J i and D i Let be the virtual inertia and virtual damping of the i-th virtual synchronizer, respectively; For time; ω i ωi is the actual output angular frequency of the i-th virtual synchronizer, and ω0 is the commanded output angular frequency value of the virtual synchronizer; P eiand P refi These are the actual and commanded values of the output active power of the i-th virtual synchronous machine, respectively.
[0063] Based on the grouping in step S2, the virtual synchronizers of the multi-virtual synchronous grid power system are divided into two groups: the leading group and the remaining group. The virtual synchronizers in the leading group are then aggregated to obtain:
[0064] ;
[0065] Where S is the set of virtual synchronizers in the leading group. , , These are the aggregated values of virtual inertia, virtual power angle, and output angular frequency of the virtual synchronizers in the leading group, respectively. , These are the aggregated values of the actual output active power and the aggregated values of the command output of the virtual synchronizer in the leading group, respectively.
[0066] Aggregating the virtual synchronizers in the remaining group yields:
[0067] ;
[0068] Where A is the set of virtual synchronizers in the remaining group, and j represents the j-th virtual synchronizer in the remaining group. , , These are the aggregated values of virtual inertia, virtual power angle, and output angular frequency for the virtual synchronizers in the remaining group, respectively. , These are the aggregated values of the actual output active power and the aggregated values of the command output of the virtual synchronizers in the remaining groups, respectively.
[0069] Then, using the equivalent aggregation based on the center of inertia as shown in the following formula, the two groups of systems are equivalent to single-machine systems:
[0070] ;
[0071] In the formula: , , , , These are the equivalent virtual power angle value, equivalent virtual inertia value, equivalent output active power actual value, equivalent active power command value, and equivalent damping power value of the equivalent single unit, respectively. , These are the aggregated virtual inertia and aggregated virtual power angle values of the virtual synchronizers in the leading group, respectively. , These are the aggregated values of the actual and commanded active power outputs of the virtual synchronizers in the leading group, respectively. , These are the aggregated values of virtual inertia and virtual power angle for the virtual synchronizers in the remaining group, respectively. , These are the aggregated values of the actual and commanded active power outputs of the virtual synchronizers in the remaining groups, respectively. , These are the virtual damping values for the i-th virtual synchronizer of the leading group and the j-th virtual synchronizer of the remaining group, respectively. , These are the actual output angular frequencies of the i-th virtual synchronizer in the leading group and the j-th virtual synchronizer in the remaining groups, respectively. This is the output angular frequency command value of the virtual synchronizer.
[0072] In step S4, the method for determining whether the virtual synchronizers in the remaining group are in an acceleration or deceleration state during the system acceleration phase includes:
[0073] Based on the virtual inertia of all virtual synchronizers in the remaining group The aggregation yields the aggregated virtual inertia values of the virtual synchronizers in the remaining group. , is represented as: ;
[0074] Based on the virtual inertia of all virtual synchronizers in the remaining group Actual value of output angular frequency The virtual inertia aggregation value of the virtual synchronizers in the remaining group The aggregated output angular frequency values of the virtual synchronizers in the remaining group were calculated. , is represented as: ;
[0075] Aggregate the output angular frequency values of the virtual synchronizers in the remaining group. The angular acceleration dω was calculated. A / dt, where t is time;
[0076] If the angular acceleration dω A / dt>0 (i.e., d) 2 δ A / dt 2 If the angular acceleration dω > 0), then the virtual synchronizers in the remaining group are in an accelerated state; if the angular acceleration dω > 0, then the virtual synchronizers in the remaining group are in an accelerated state; A / dt<0 (i.e., d) 2 δ A / dt 2 If <0, then the virtual synchronizers in the remaining group are determined to be in a deceleration state.
[0077] In step S4, the method for determining the system acceleration phase includes:
[0078] Based on the virtual inertia of all virtual synchronizers in the leader group The aggregation yields the aggregated virtual inertia values of the virtual synchronizers in the leading group. Based on the virtual inertia of all virtual synchronizers in the leading group. Virtual power angle The aggregated value of virtual inertia of virtual synchronizers in the leading group The virtual power angle aggregation value of the virtual synchronizers in the leading group is calculated. ;
[0079] Based on the virtual inertia of all virtual synchronizers in the remaining group Virtual power angle The virtual inertia aggregation value of the virtual synchronizers in the remaining group The virtual power angle aggregation value of the virtual synchronizers in the remaining group is calculated. ;
[0080] Based on the virtual power angle aggregation value of the virtual synchronizer in the leading group The virtual power angle aggregation value of the virtual synchronizers in the remaining group The equivalent virtual power angle value of the equivalent single machine is calculated. ; ;
[0081] Based on the equivalent virtual power angle value of the equivalent single machine The equivalent single-machine angular acceleration d was calculated. 2 δ eq / dt 2 ;
[0082] If the equivalent single-machine angular acceleration d 2 δ eq / dt 2 If the value is greater than 0, the multi-virtual synchronous grid power system is determined to be in the acceleration phase. Generally, the acceleration phase of a multi-virtual synchronous grid power system begins at the time of fault occurrence and ends at the time of fault clearance; if the equivalent single-machine angular acceleration d... 2 δ eq / dt 2 If the value is less than 0, the multi-virtual synchronous grid power system is determined to be in the deceleration phase; the change in the sign of the second derivative is determined by the unbalanced power reversal at the moment of fault clearing, and serves as the trigger condition for switching the damping adjustment logic.
[0083] Verification Example 1: Building a system on the PSCAD / EMTDC platform, such as... Figure 3 The three-machine, nine-node system shown has VSG1~VSG3 connected to the network via a step-up transformer. A schematic diagram of its active power loop control principle is shown below. Figure 2 ,exist Figure 3 A three-phase short-circuit fault is set at node ①, with a fault duration of 0.103s. The swing equation of the VSG is:
[0084]
[0085] In the formula: subscripts 1, 2, and 3 represent the relevant variables of the grid-type converters VSG1, VSG2, and VSG3, respectively.
[0086] According to the above grouping rules, the power angle trajectory during the fault is as follows: Figure 4 As shown: VSG2 is classified into the leading group (S group), while VSG1 and VSG3 are classified into the remaining group (A group). Clearly... Figure 4 ω A >ω0, the rotational speed of the remaining groups increases.
[0087] The remaining group aggregation models are as follows, and the leader-leader group aggregation method is similar and will not be repeated.
[0088]
[0089] The difference in work angle between the leading group and the remaining groups is Δδ=δ S −δ A With the horizontal axis as the derivative corresponding to the power angle difference, i.e., the speed difference Δω = ω S −ω A Plot the phase plane trajectory with the vertical axis as the y-axis. If the trajectory fails to cross zero and continues to expand outward, the system is considered unstable; if the trajectory is captured by the attraction domain and eventually returns to the stable equilibrium point, the system is considered stable. Figure 6 Given the remaining group acceleration conditions, D A The phase plane trajectory when ω0 is 10000, 18000, and 24000. When D... A ω0 = 18000 or D A When ω0 = 24000, the trajectory crosses the saddle point and continues to expand outward, causing the system to become unstable; when D A When ω0 = 10000, the trajectory is captured by the attraction domain of the stable equilibrium point. It turns back without crossing the boundary, and the system eventually returns to the stable equilibrium point and regains stability.
[0090] Further quantitative evaluation using EEAC is employed, as shown in the following formula. The two groups are aggregated into a single-machine system, an iso-P-δ curve is plotted, the acceleration / deceleration area and critical energy are calculated, and the stability margin η after damping adjustment is obtained.
[0091]
[0092] Acceleration and deceleration area:
[0093]
[0094] In the formula, A inc To accelerate the area, A dec δ is the acceleration area; δ0 is the power angle during steady-state operation; δ c For fault clearing angle; P meq The equivalent mechanical power is P. refeq -P Deq ;δ u When the system is stable, it represents the power angle at the farthest point; when the system is unstable, it represents the power angle at the unstable equilibrium point.
[0095] Stability margin:
[0096]
[0097] In the formula, η is the stability margin, and A inc To accelerate the area, A dec To accelerate the area, A dec.pot The hypothetical area is the minimum additional kinetic energy required to make the system at its farthest point just lose its synchronous stability. This value can be calculated using the extended equal area rule.
[0098] Tables 1 and 2 quantitatively list the acceleration area, deceleration area, and stability margin of the leading and remaining groups under different damping conditions. To visually demonstrate the impact of damping adjustment on the power angle characteristics, Figure 7 Given different leading groups D S The equivalent P-δ curve corresponding to ω0 shows that the equivalent mechanical power decreases significantly with increasing damping, the power angle corresponding to fault clearing decreases significantly, and the acceleration area decreases significantly. Figure 9 Furthermore, under the accelerated operating condition of the remainder group, different remainder groups D are given. A The P-δ curve corresponding to ω0 indicates that reducing D A The equivalent mechanical power is reduced, the corresponding power angle is reduced when the fault is cleared, the acceleration area is reduced, and the stability margin is improved.
[0099] Table 1: Acceleration / deceleration area and stability margin for different leading group dampers
[0100]
[0101] Table 2: Acceleration / deceleration area and stability margin of different residual group dampers during residual group acceleration in the fault phase.
[0102]
[0103] Verification Example 2: A three-phase short-circuit fault is set at node ②, lasting 0.085s. The power angle trajectory during the fault is as follows. Figure 5 As shown, VSG3 is the leading group (S group), and VSG1 and VSG2 are the remaining groups (A group). Clearly... Figure 5 ω A When ω > 0, the rotational speed of the remaining groups increases. The aggregation method is the same as in verification example 1, and will not be repeated here.
[0104] Figure 8 Given the remaining group deceleration conditions, D A The phase plane trajectory when ω0 is 10000, 18000, and 24000. When D... A When ω0 = 10000, the trajectory crosses the saddle point and continues to expand outward, causing the system to become unstable; when D A When ω0 increases to 18000 and 24000, the trajectory is captured by the attraction domain of the stable equilibrium point, and turns back without exceeding the boundary. The system eventually returns to the stable equilibrium point and regains stability. Table 3 quantitatively lists the acceleration area, deceleration area, and stability margin under the above conditions. When D A When ω0 increases from 10000 to 24000, the acceleration area gradually decreases, and the stability margin increases from -2.457% to 3.482%, verifying the effectiveness of the control rule that the damping should be increased in the remaining deceleration conditions.
[0105] To visually demonstrate the impact of damping adjustment on the power angle characteristics, Figure 11 Under the deceleration condition of the remaining group, different remaining group D are given. A The P-δ curve corresponding to ω0 indicates that increasing D... A The equivalent mechanical power is reduced, the corresponding power angle is reduced when the fault is cleared, the acceleration area is reduced, and the stability margin is improved.
[0106] Table 3: Acceleration / deceleration area and stability margin for different residual group dampers during residual group deceleration in the fault phase.
[0107]
[0108] The above embodiments verify the parameter tuning method of this application: the virtual damping of the virtual synchronizer in the leading group is always increased uniformly; during the system fault acceleration phase, the virtual damping of the virtual synchronizers in the remaining group is decreased when the speed increases and increased when the speed decreases.
[0109] Example 2: Based on Example 1, this example provides a transient stability damping parameter tuning device for a multi-virtual synchronous grid-connected power system, comprising:
[0110] The acquisition module is used to: in response to the detection of a line fault, acquire the disturbed electromechanical transient trajectories of each virtual synchronous machine in a multi-virtual synchronous network power system;
[0111] The partitioning module is used to: based on the disturbed electromechanical transient trajectory, divide each virtual synchronous machine in the multi-virtual synchronous network power system into a leading group and a remaining group;
[0112] The adjustment module is used to: increase the virtual damping of the virtual synchronizer in the leading group; decrease the virtual damping of the virtual synchronizer in the remaining group if the virtual synchronizer in the remaining group is in an accelerating state during the system acceleration phase; and increase the virtual damping of the virtual synchronizer in the remaining group if the virtual synchronizer in the remaining group is in a decelerating state during the system acceleration phase.
[0113] Example 3: Based on Example 1, this example provides a transient stability damping parameter tuning system for a multi-virtual synchronous grid power system, including a processor and a storage medium;
[0114] The storage medium is used to store instructions;
[0115] The processor is configured to operate according to the instructions to execute the method according to Embodiment 1.
[0116] Example 4: Based on Example 1, this example provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the method described in Example 1.
[0117] Example 5: Based on Example 1, this example provides a computer device, including a memory and a processor. The memory stores a computer program, and the processor executes the computer program to implement the method described in Example 1.
[0118] Example 6: Based on Example 1, this example provides a computer program product, including a computer program that, when executed by a processor, implements the method described in Example 1.
[0119] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product embodied on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.
[0120] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, as well as combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.
[0121] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.
[0122] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.
[0123] The above description is only a preferred embodiment of this application. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of this application, and these improvements and modifications should also be considered within the scope of protection of this application.
Claims
1. A method for tuning transient stability damping parameters in a multi-virtual synchronous grid-connected power system, characterized in that, include: In response to the detection of a line fault, the disturbed electromechanical transient trajectories of each virtual synchronizer in a multi-virtual synchronous network power system are acquired; Based on the disturbed electromechanical transient trajectory, each virtual synchronous machine in the multi-virtual synchronous grid power system is divided into a leading group and a remaining group. For the virtual synchronizer in the leading group, increase the virtual damping of the virtual synchronizer; For the virtual synchronizers in the remaining group, if the virtual synchronizer in the remaining group is in an accelerating state during the system acceleration phase, then the virtual damping of the virtual synchronizer is reduced; if the virtual synchronizer in the remaining group is in a decelerating state during the system acceleration phase, then the virtual damping of the virtual synchronizer is increased.
2. The method according to claim 1, characterized in that, In a multi-virtual synchronous grid-connected power system, all grid-connected converters employ virtual synchronous control, and the active power control equation is as follows: ； In the formula: J and D are virtual inertia and virtual damping, respectively; t is time; ω and ω0 are the actual and commanded values of the converter output angular frequency, respectively; P e and P ref These are the actual and commanded values of the active power output by the converter, respectively. Dω0 (ω-ω0) is the damping term of the grid-type converter, which is transformed into: ； In the formula: ω is the difference between the actual value ω and the commanded value ω0 of the converter output angular frequency, and δ is the virtual power angle of the grid-type converter, used to characterize the angle between the common coupling point voltage and the converter voltage.
3. The method according to claim 1, characterized in that, Based on the disturbed electromechanical transient trajectory, each virtual synchronous machine in the multi-virtual synchronous grid power system is divided into a leading group and a remaining group, including: At each sampling time, n disturbed electromechanical transient trajectories are projected onto a one-dimensional power angle axis and arranged in ascending order of value to generate n−1 adjacent gaps; If a gap grows unbounded over time among n-1 adjacent gaps, it is determined to be an unbounded position gap. In a multi-virtual synchronous grid power system, the virtual synchronous machines are divided into a leading group whose power angle is above the unbounded position gap and the remaining group whose power angle is below the unbounded position gap.
4. The method according to claim 1, characterized in that, Increase the virtual damping of the virtual synchronizer, including: The virtual damping D of the virtual synchronous machine is adjusted from the initial value D0 to kD0, where k is the damping amplification factor, k>1; and the adjustment of the virtual damping of the virtual synchronous machine is obtained by comprehensive tuning through offline simulation analysis based on the severity of disturbances that the multi-virtual synchronous grid power system can withstand.
5. The method according to claim 1, characterized in that, A multi-virtual synchronous grid power system contains n virtual synchronous machines. For any virtual synchronous machine, the rotor motion equation of the i-th virtual synchronous machine is: ； In the formula: J i and D i Let be the virtual inertia and virtual damping of the i-th virtual synchronizer, respectively; For time; ω i ωi is the actual output angular frequency of the i-th virtual synchronizer, and ω0 is the commanded output angular frequency value of the virtual synchronizer; P ei and P refi These are the actual and commanded values of the output active power of the i-th virtual synchronous machine, respectively. Aggregating the virtual synchronizers in the leader group yields: ； Where S is the set of virtual synchronizers in the leading group. , , These represent the aggregated values of virtual inertia, virtual power angle, and output angular frequency of the virtual synchronizers in the leading group, respectively. , These are the aggregated values of the actual and commanded active power outputs of the virtual synchronizers in the leading group, respectively. Aggregating the virtual synchronizers in the remaining group yields: ； Where A is the set of virtual synchronizers in the remaining group, and j represents the j-th virtual synchronizer in the remaining group. , , These are the aggregated values of virtual inertia, virtual power angle, and output angular frequency for the virtual synchronizers in the remaining group, respectively. , These are the aggregated values of the actual output active power and the aggregated values of the command output of the virtual synchronizers in the remaining groups, respectively. Using inertia center-based equivalent aggregation, all virtual synchronizers divided into leading and remaining groups are equivalent to single-machine systems. ； In the formula: , , , , These are the equivalent virtual power angle value, equivalent virtual inertia value, equivalent output active power actual value, equivalent active power command value, and equivalent damping power value of the equivalent single unit, respectively. , These are the aggregated virtual inertia and aggregated virtual power angle values of the virtual synchronizers in the leading group, respectively. , These are the aggregated values of the actual and commanded active power outputs of the virtual synchronizers in the leading group, respectively. , These are the aggregated values of virtual inertia and virtual power angle for the virtual synchronizers in the remaining group, respectively. , These are the aggregated values of the actual and commanded active power outputs of the virtual synchronizers in the remaining groups, respectively. , These are the virtual damping values for the i-th virtual synchronizer of the leading group and the j-th virtual synchronizer of the remaining group, respectively. , These are the actual output angular frequencies of the i-th virtual synchronizer in the leading group and the j-th virtual synchronizer in the remaining groups, respectively. This is the output angular frequency command value of the virtual synchronizer.
6. The method according to claim 1, characterized in that, The methods for determining whether the virtual synchronizers in the remaining groups are in an accelerated or decelerated state during the system acceleration phase include: Based on the virtual inertia of all virtual synchronizers in the remaining group The aggregation yields the aggregated virtual inertia values of the virtual synchronizers in the remaining group. ; Based on the virtual inertia of all virtual synchronizers in the remaining group Actual value of output angular frequency The virtual inertia aggregation value of the virtual synchronizers in the remaining group The aggregated output angular frequency values of the virtual synchronizers in the remaining group were calculated. ; Aggregate the output angular frequency values of the virtual synchronizers in the remaining group. The angular acceleration dω was calculated. A / dt, where t is time; If the angular acceleration dω A If dt > 0, then the virtual synchronizers in the remaining group are in an accelerated state; if the angular acceleration dω A If / dt<0, then the virtual synchronizers in the remaining group are in a deceleration state.
7. The method according to claim 1, characterized in that, The methods for determining the system acceleration phase include: Based on the virtual inertia of all virtual synchronizers in the leader group The aggregation yields the aggregated virtual inertia values of the virtual synchronizers in the leading group. Based on the virtual inertia of all virtual synchronizers in the leading group. Virtual power angle The aggregated value of virtual inertia of virtual synchronizers in the leading group The virtual power angle aggregation value of the virtual synchronizers in the leading group is calculated. ; Based on the virtual inertia of all virtual synchronizers in the remaining group Virtual power angle The virtual inertia aggregation value of the virtual synchronizers in the remaining group The virtual power angle aggregation value of the virtual synchronizers in the remaining group is calculated. ; Based on the virtual power angle aggregation value of the virtual synchronizer in the leading group The virtual power angle aggregation value of the virtual synchronizers in the remaining group The equivalent virtual power angle value of the equivalent single machine is calculated. ; Based on the equivalent virtual power angle value of the equivalent single machine The equivalent single-machine angular acceleration d was calculated. 2 δ eq / dt 2 t is time; If the equivalent single-machine angular acceleration d 2 δ eq / dt 2 If the value is greater than 0, the multi-virtual synchronous grid power system is determined to be in the acceleration phase.
8. A device for tuning transient stability damping parameters in a multi-virtual synchronous grid-connected power system, characterized in that, include: The acquisition module is used to: in response to the detection of a line fault, acquire the disturbed electromechanical transient trajectories of each virtual synchronous machine in a multi-virtual synchronous network power system; The partitioning module is used to: based on the disturbed electromechanical transient trajectory, divide each virtual synchronous machine in the multi-virtual synchronous network power system into a leading group and a remaining group; The adjustment module is used to: increase the virtual damping of the virtual synchronizer in the leading group; decrease the virtual damping of the virtual synchronizer in the remaining group if the virtual synchronizer in the remaining group is in an accelerating state during the system acceleration phase; and increase the virtual damping of the virtual synchronizer in the remaining group if the virtual synchronizer in the remaining group is in a decelerating state during the system acceleration phase.
9. A transient stability damping parameter tuning system for a multi-virtual synchronous grid-connected power system, characterized in that, Including processor and storage media; The storage medium is used to store instructions; The processor is configured to operate according to the instructions to perform the method according to any one of claims 1 to 7.
10. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by a processor, it implements the method according to any one of claims 1 to 7.
11. A computer device comprising a memory and a processor, wherein the memory stores a computer program, characterized in that, When the processor executes the computer program, it implements the method according to any one of claims 1 to 7.