New energy single-line sending-out system sending-out limit improving method and device

Abstract

The invention provides a new energy single-line sending-out system sending-out limit improving method and device. The new energy single-line sending-out system sending-out limit improving method mainly comprises the steps that control parameters of a system in the low-voltage ride-through and after-fault recovery process are set; aC line single-phase instantaneous grounding reclosing success fault scanning is carried out on the system; and when the system reaches a critical stable state, recording the first new energy output at the moment. Setting the maintenance time of the active climbing initial value after the fault in the control parameters; fault scanning is carried out again based on the new control parameters; and recording the second new energy output at the moment. And if the second new energy output is greater than the first new energy output, performing post-fault control by adopting a new control parameter so as to improve the delivery limit of the system. According to the method, the active climbing initial value maintaining time after the fault is optimized, so that the new energy power station can maintain low-power operation in the non-full-phase operation period after the single transient fault, the active power is quickly recovered after reclosing succeeds, and the sending limit of the new energy single-line sending system is improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of power grid planning and operation of electric power systems, and specifically relates to a method and device for improving the transmission limit of a new energy single-line transmission system. Background Art

[0002] The development and utilization of new energy sources continues to grow globally, especially in areas with abundant wind and solar resources. However, these new energy-intensive areas are usually located in remote areas, far away from major urban load centers. In addition, the average output level of new energy power generation facilities is low. Based on multiple technical and economic considerations, single-circuit AC long-distance transmission lines may be used to achieve long-distance transmission of large-scale new energy electricity, which leads to the scenario of large-scale new energy being transmitted through single-circuit AC long lines.

[0003] In large-scale single-line transmission systems of renewable energy, the handling of "single-phase instantaneous ground reclosing success failure" is particularly critical, because it directly affects the stable operation of the system after fault recovery and its power transmission limit. This indicator is not only an important consideration in grid planning and operation, but also usually relies on complex electromechanical simulation calculations to obtain accurate data. However, the current renewable energy low voltage ride-through (LVRT) control strategy tends to restore power immediately after the fault is cleared. Although this approach aims to restore power as quickly as possible, it brings new challenges: during the non-full capacity operation stage after the system experiences a single-phase instantaneous fault, the renewable energy device frequently triggers the low voltage ride-through function, causing large fluctuations in the power of the transmission line. As a result, the system's power transmission capacity is limited, and in order to ensure stability, the output of renewable energy has to be constrained for a long time, which exacerbates the phenomenon of power abandonment, which constitutes an obstacle to the full utilization of clean energy. Summary of the invention

[0004] In view of this, the present invention provides a method and device for improving the transmission limit of a new energy single-line transmission system, aiming to optimize the maintenance time of the initial value of the active power climbing of the new energy after a fault, so that the new energy can maintain a relatively low power operation during the non-full-phase operation after a single-instantaneous fault, and the active power of the new energy is quickly restored after the reclosing is successful, thereby avoiding large power oscillations during the non-full-phase operation of the new energy single-line transmission system and improving the transmission limit of the new energy single-line transmission system.

[0005] In order to achieve the above object, the technical solution provided by the present invention is as follows:

[0006] In a first aspect, the present invention provides a method for improving the delivery limit of a new energy single-line delivery system, comprising the following steps:

[0007] Set the control parameters of the new energy single-line transmission system during low voltage ride-through and post-fault recovery;

[0008] Based on the control parameters, the AC line single-phase instantaneous ground reclosing failure scanning was successfully performed on the new energy single-line transmission system;

[0009] When the new energy single-line transmission system reaches a critical stable state, record the first new energy output of the system when the system is critically stable under a single instantaneous fault;

[0010] The maintenance time of the initial value of active power ramp after a fault is set in the control parameters to obtain new control parameters;

[0011] Based on the new control parameters, the AC line single-phase instantaneous ground reclosing fault scanning was successfully performed on the new energy single-line transmission system;

[0012] When the new energy single-line transmission system reaches a critical stable state, record the second new energy output of the system when the system is critically stable under a single instantaneous fault;

[0013] The output of the first new energy source is compared with the output of the second new energy source. If the output of the second new energy source is greater than the output of the first new energy source, the new energy single-line transmission system is controlled after a fault with new control parameters to increase the transmission limit of the new energy single-line transmission system.

[0014] Furthermore, the AC line single-phase instantaneous ground reclosing failure scanning is successfully performed on the new energy single-line transmission system, including:

[0015] Based on the set initial active power of new energy, the single-line transmission system of new energy is scanned for successful faults of single-phase instantaneous grounding reclosing of AC line;

[0016] Determine whether the new energy single-line transmission system has reached a critical stable state;

[0017] If not, the active power of renewable energy is increased according to the set step size until the system reaches a critical stable state.

[0018] Furthermore, the critical stability state includes: a critical state when the system is unstable and a critical state when the new energy is running at full power.

[0019] Furthermore, the control parameters include at least: a low voltage active power control value, an initial value of active power ramping after a fault, a maintenance time of the initial value of active power ramping after a fault, and an active power ramping rate after a fault.

[0020] Furthermore, when setting the control parameters of the new energy single-line transmission system during low voltage ride-through and post-fault recovery, the maintenance time of the initial value of active power ramp after the fault is set to zero.

[0021] In a second aspect, the present invention provides a device for increasing the delivery limit of a new energy single-line delivery system, comprising:

[0022] The parameter setting module is used to set the control parameters of the new energy single-line transmission system during low voltage ride-through and post-fault recovery; it is also used to set the initial value maintenance time of active power ramp after the fault in the control parameters to obtain new control parameters;

[0023] The fault scanning module is used to perform a successful fault scan of a single-phase instantaneous ground reclosing switch of an AC line on a new energy single-line transmission system based on control parameters; and is also used to perform a successful fault scan of a single-phase instantaneous ground reclosing switch of an AC line on a new energy single-line transmission system based on new control parameters;

[0024] A data recording module, used for recording the first new energy output and the second new energy output of the system when the single-line new energy transmission system reaches a critical stable state at a single instantaneous fault critical stability;

[0025] The transmission limit improvement module is used to compare the first new energy output and the second new energy output. If the second new energy output is greater than the first new energy output, the new energy single-line transmission system is controlled after a fault with new control parameters to improve the transmission limit of the new energy single-line transmission system.

[0026] Furthermore, the AC line single-phase instantaneous ground reclosing failure scanning is successfully performed on the new energy single-line transmission system, including:

[0027] Based on the set initial active power of new energy, the single-line transmission system of new energy is scanned for successful faults of single-phase instantaneous grounding reclosing of AC line;

[0028] Determine whether the new energy single-line transmission system has reached a critical stable state;

[0029] If not, the active power of renewable energy is increased according to the set step size until the system reaches a critical stable state.

[0030] Furthermore, the critical stability state includes: a critical state when the system is unstable and a critical state when the new energy is running at full power.

[0031] Furthermore, the control parameters include at least: a low voltage active power control value, an initial value of active power ramping after a fault, a maintenance time of the initial value of active power ramping after a fault, and an active power ramping rate after a fault.

[0032] Furthermore, when setting the control parameters of the new energy single-line transmission system during low voltage ride-through and post-fault recovery, the maintenance time of the initial value of active power ramp after the fault is set to zero.

[0033] In summary, the present invention provides a method and device for improving the transmission limit of a new energy single-line transmission system, including setting control parameters of the new energy single-line transmission system during low voltage crossing and post-fault recovery; based on the control parameters, performing a successful fault scan of a single-phase instantaneous grounding reclosing switch of an AC line on the new energy single-line transmission system; when the new energy single-line transmission system reaches a critical stable state, recording the first new energy output of the system when the single-instantaneous fault is critically stable; setting the initial value maintenance time of active power climbing after the fault in the control parameters to obtain new control parameters; based on the new control parameters, re-scanning the successful fault of a single-phase instantaneous grounding reclosing switch of an AC line on the new energy single-line transmission system; when the new energy single-line transmission system reaches a critical stable state, recording the second new energy output of the system when the single-instantaneous fault is critically stable; comparing the first new energy output and the second new energy output, if the second new energy output is greater than the first new energy output, performing post-fault control on the new energy single-line transmission system with the new control parameters to improve the transmission limit of the new energy single-line transmission system. The present invention optimizes the maintenance time of the initial value of the active power ramp of the new energy after a fault, so that the new energy can maintain a relatively low power operation during the non-full-phase operation after a single-momentary fault, and the active power of the new energy is quickly restored after the reclosing is successful, thereby avoiding the large power oscillation during the non-full-phase operation of the new energy single-line transmission system and improving the transmission limit of the new energy single-line transmission system. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0035] Figure 1 A flowchart of a method for improving the delivery limit of a new energy single-line delivery system provided by an embodiment of the present invention;

[0036] Figure 2 A schematic diagram of a new energy single-line transmission system provided by the present invention;

[0037] Figure 3 A power curve diagram of the transmission line after a single instantaneous fault occurs in the system under the initial new energy control parameters provided by the embodiment of the present invention;

[0038] Figure 4 A power curve of the transmission line after a single instantaneous fault occurs in the system under the optimized new energy control parameters provided in the embodiment of the present invention;

[0039] Figure 5A block diagram of a device for improving the delivery limit of a new energy single-line delivery system provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0040] In order to make the purpose, features and advantages of the present invention more obvious and easy to understand, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the embodiments described below are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0041] See also Figure 1 and Figure 2 , Figure 1 The flow chart of a method for improving the delivery limit of a new energy single-line delivery system of the present invention is shown; Figure 2 A new energy single-line transmission system is shown. Figure 2 The problems existing in the existing new energy single-line transmission system during low voltage ride-through and fault recovery are introduced.

[0042] Figure 2 The schematic diagram of a typical single-line transmission system for renewable energy is shown, which includes three main components: renewable energy power sources, representing renewable energy power generation devices such as wind power and solar power; transmission lines, which are transmission lines connecting the renewable energy power sources with the receiving system; and the receiving system, which is the power grid system that receives the electricity generated by renewable energy, usually including loads and other power sources.

[0043] In this system, the electricity generated by renewable energy is transmitted to the receiving system through the transmission line. Since the areas with dense renewable energy are often far away from the load center, long-distance transmission lines are required to achieve power transmission. However, this configuration also brings some challenges, especially when dealing with "single-phase instantaneous ground reclosing success fault".

[0044] In this fault scenario, the traditional low voltage ride through (LVRT) control strategy of renewable energy usually restores power immediately after the fault is cleared. This causes renewable energy to frequently enter and exit the low voltage ride through state during non-full-phase operation (i.e., the short period when the fault is not completely cleared), which in turn causes large fluctuations in the power of the transmission line. As a result, the system's transmission power limit is relatively low. In order to ensure the stable operation of the system, it is often necessary to limit the power output of renewable energy for a long time, which increases the risk of renewable energy being abandoned (the so-called "power abandonment" phenomenon).

[0045] Based on this, the present invention provides a method and device for improving the delivery limit of a new energy single-line delivery system. An embodiment of a method for improving the delivery limit of a new energy single-line delivery system of the present invention is introduced below.

[0046] See also Figure 1 The embodiment of the present invention provides a method for improving the delivery limit of a new energy single-line delivery system, comprising the following steps:

[0047] Step 1: Set the control parameters of the new energy single-line transmission system during low voltage ride-through and post-fault recovery.

[0048] It should be noted that low voltage ride through (LVRT) refers to the ability of a new energy power station (such as a wind farm or photovoltaic power station) to continue operating without being disconnected from the grid when the grid voltage suddenly drops.

[0049] This step first defines the various control parameters of the new energy single-line transmission system during low voltage ride-through (LVRT) and post-fault recovery.

[0050] Step 2: Based on the control parameters, perform a successful fault scan of the single-phase instantaneous ground reclosing of the AC line of the new energy single-line transmission system.

[0051] It should be noted that this step uses the initially set control parameters to conduct a simulation test of the "single-phase instantaneous grounding reclosing successful fault" on the new energy single-line transmission system. That is, a common single-phase instantaneous grounding fault in the power grid is simulated, and then the reclosing is successful to observe the performance of the system.

[0052] Step 3: When the new energy single-line transmission system reaches a critical stable state, record the first new energy output of the system when it is critically stable under a single instantaneous fault.

[0053] It should be noted that the critical stability state refers to the state where the system is on the verge of losing stability. Specifically, the critical stability state refers to the limit state where the system can maintain stable operation under certain conditions. In this state, the system is very sensitive to external disturbances (such as failures), and any slight change may cause the system to change from a stable state to an unstable state.

[0054] When the system reaches a critical stable state after experiencing a successful single-phase instantaneous ground reclosing fault, the output of the new energy power station at this time is recorded as the first new energy output value.

[0055] Step 4: Set the initial value maintenance time of active power ramp after fault in the control parameters to obtain new control parameters.

[0056] It should be noted that, based on the original control parameters, a new set of control parameters is formed by adding or modifying the maintenance time of the initial value of active power ramp after a fault. By adjusting the time length for the power station to restore active power after the fault is cleared, a better recovery strategy can be found.

[0057] Step 5: Based on the new control parameters, re-scan the AC line single-phase instantaneous ground reclosing failure successfully for the new energy single-line transmission system.

[0058] It should be noted that the simulation test of the single-phase instantaneous ground reclosing successful fault was performed again using the newly set control parameters.

[0059] Step 6: When the new energy single-line transmission system reaches a critical stable state, record the second new energy output of the system when it is critically stable under a single instantaneous fault.

[0060] It should be noted that when the system reaches the critical stable state again, the output of the new energy power station at this time is recorded as the second new energy output.

[0061] Step 7: Compare the first new energy output and the second new energy output. If the second new energy output is greater than the first new energy output, perform post-fault control on the new energy single-line transmission system with new control parameters to increase the transmission limit of the new energy single-line transmission system.

[0062] It should be noted that, by comparing the output values ​​of the two test records, if the output of the second new energy source is greater than the output of the first new energy source, it indicates that the new control parameters can improve the output limit of the system. At this time, the new control parameters can be used to guide the post-fault recovery process in the actual system.

[0063] This embodiment provides a method for improving the transmission limit of a new energy single-line transmission system. By optimizing the maintenance time of the initial value of the active power ramp of new energy after a fault, the new energy power station can maintain a lower power level during the non-full-phase operation after a single instantaneous fault. After the reclosing is successful, the new energy power station can restore its active power more quickly, thereby avoiding the large oscillation of the power of the transmission line during the non-full-phase operation. In this way, the transmission limit of the new energy single-line transmission system can be improved and the risk of power abandonment can be reduced. The method proposed in this embodiment reduces the power oscillation during the non-full-phase operation and enhances the stability of the system by optimizing the maintenance time of the initial value of the active power ramp. The optimized control strategy allows the active power to be restored more effectively after a fault, thereby improving the maximum transmission capacity of the new energy single-line transmission system. By increasing the transmission limit, the phenomenon of new energy abandonment due to system instability can be reduced, and the utilization rate of clean energy can be improved.

[0064] In one embodiment, a single-phase instantaneous ground reclosing failure scanning is performed on a new energy single-line transmission system, including:

[0065] Based on the set initial active power of new energy, the single-phase instantaneous grounding reclosing failure scan of the AC line of the new energy single-line transmission system is successfully carried out.

[0066] Determine whether the new energy single-line transmission system has reached a critical stable state;

[0067] If not, the active power of renewable energy is increased according to the set step size until the system reaches a critical stable state.

[0068] The fault scanning process proposed in this embodiment is a process of gradually approaching the stability limit of the system. By continuously adjusting the active power output of the new energy power station (for example, increasing the active power of the new energy by 1% each time), the stability of the system at different power levels can be explored. Finally, the active power level when the system reaches the critical stable state is found, that is, the highest power level at which the system can still maintain stability after a single-phase instantaneous grounding fault occurs and the circuit breaker is successfully reclosed. This method can accurately find the maximum active power output that can be maintained stable by the new energy single-line transmission system after a specific type of fault occurs.

[0069] In one embodiment, the critical stable state includes: a critical state when the system is unstable and a critical state when the new energy source is running at full power.

[0070] In this embodiment, the critical stability state includes two aspects: the critical state when the system is unstable and the critical state when the new energy is running at full power. These two critical states represent two extreme conditions of system stability.

[0071] The critical state of system instability refers to the state in which the system is about to lose stability after being disturbed (such as the failure of a single-phase instantaneous ground reclosing success). In this state, the system's performance is already very unstable, and any small additional disturbance may cause the system to enter a completely unstable state. The critical state of renewable energy when operating at full power refers to the state in which a renewable energy power station (such as a wind power station or a photovoltaic power station) operates near its designed maximum output power level. In this state, if the load continues to increase or attempts to further increase the output power are made, it may cause equipment overload or system instability.

[0072] In one embodiment, the control parameters include at least: a low voltage active power control value, an initial value of active power ramping after a fault, a maintenance time of the initial value of active power ramping after a fault, and an active power ramping rate after a fault.

[0073] In this embodiment, the low voltage active power control value refers to the active power level that the new energy power station needs to output in order to maintain the stability of the power grid when the power grid voltage drops. This parameter is used to ensure that during the voltage drop, the power station will not be immediately disconnected from the grid, but continue to provide a certain amount of active power support to the grid.

[0074] The initial value of active power ramp after a fault is the initial target value when the new energy power station restores active power output after the grid fault is cleared. This parameter determines the speed and degree of active power recovery of the power station from the initial stage of fault recovery.

[0075] The maintenance time of the initial value of active power ramp after a fault refers to the length of time the power station maintains the initial active power level from the initial stage of fault recovery. During this period, the power station will maintain a fixed active power output until the set time ends.

[0076] The active power ramp rate after a fault refers to the rate at which the active power increases per unit time during the power station recovery process. This parameter determines the speed at which the power station recovers to normal power levels.

[0077] These control parameters work together to determine the behavior of the new energy single-line transmission system during the recovery process after a fault. By fine-tuning these parameters, the system can be quickly recovered after a fault while maintaining system stability and security.

[0078] In one embodiment, when setting control parameters of the new energy single-line transmission system during low voltage ride-through and post-fault recovery, the maintenance time of the initial value of active power ramp after the fault is set to zero.

[0079] In this embodiment, the maintenance time of the initial value of active power ramp after a fault is set to zero, which means that after the fault is cleared, the new energy single-line transmission system does not need to stay at the initial active power level for any time, but immediately starts the ramp of active power. Setting the maintenance time of the initial value of active power ramp after a fault to zero can be used as a reference point before optimization. At this reference point, the power station will not stay at the initial power level, but will start the ramp immediately. In this way, the performance of the system without the initial value maintenance time can be observed, providing a reference point for subsequent optimization.

[0080] The following is an introduction to the lifting method of the present invention with reference to a calculation example. Figure 2 Take the new energy single-line transmission system shown as an example.

[0081] In this example, the installed capacity of renewable energy is 2 million kilowatts, and the length of the transmission line is 120 km. The improvement method includes the following steps:

[0082] 1. According to the conventional method, specify the low voltage active power control value Plow=0.1P1, the initial value of active power ramp after fault Ps=Plow, the initial value of active power ramp after fault T=0, and the active power ramp rate after fault Prate=1pu / s. Set the initial active power P1 of new energy in the study area to 0.

[0083] 2. Under the initial control parameters of new energy, the new energy output Pmax1 of the new energy single-line transmission system when the single instantaneous fault is critically stable is recorded to be 1 million kilowatts. Figure 3 This is the active power curve of the transmission line after a single instantaneous fault occurs in the system under the initial new energy control parameters and when the initial power of the new energy is 2 million kilowatts. It can be found that during the non-full-phase operation, the power of the transmission line oscillates greatly.

[0084] 3. The maintenance time of the initial value of the new energy active power ramp after the specified fault is T2=1.1s.

[0085] 4. Under the optimized new energy control parameters, the new energy output Pmax2 = 2 million kilowatts when the single-line transmission system of the new energy is critically stable with a single instantaneous fault. Figure 4 This is the active power curve of the transmission line after a single instantaneous fault occurs in the system under the optimized new energy control parameters and when the initial power of new energy is 2 million kilowatts. It can be found that during the non-full-phase operation, the power of the transmission line has been maintained at a low level. After the reclosing is successful, the active power of the new energy is quickly restored, thus avoiding the large power oscillation of the new energy single-line transmission system during the non-full-phase operation, and improving the transmission limit of the new energy single-line transmission system.

[0086] It can be seen that by optimizing the maintenance time of the initial value of the active power ramp of new energy after a fault, the new energy can also maintain a low power operation during the non-full-phase operation after a single-instantaneous fault. After the reclosing is successful, the active power of the new energy is quickly restored, thereby avoiding the large power oscillation of the new energy single-line transmission system during the non-full-phase operation period and improving the transmission limit of the new energy single-line transmission system.

[0087] Based on the same inventive concept, the embodiment of the present application also provides a device for improving the delivery limit of a new energy single-line delivery system for realizing the above-mentioned method for improving the delivery limit of a new energy single-line delivery system. The implementation scheme for solving the problem provided by the device is similar to the implementation scheme recorded in the above-mentioned method, so the specific limitations in the embodiment of the device for improving the delivery limit of a new energy single-line delivery system provided below can be referred to the limitations of the method for improving the delivery limit of a new energy single-line delivery system above, and will not be repeated here.

[0088] See also Figure 5 The embodiment of the present invention further provides a device for improving the delivery limit of a new energy single-line delivery system, comprising:

[0089] The parameter setting module is used to set the control parameters of the new energy single-line transmission system during low voltage ride-through and post-fault recovery; it is also used to set the initial value maintenance time of active power ramp after the fault in the control parameters to obtain new control parameters;

[0090] The fault scanning module is used to perform a successful fault scan of a single-phase instantaneous ground reclosing switch of an AC line on a new energy single-line transmission system based on control parameters; and is also used to perform a successful fault scan of a single-phase instantaneous ground reclosing switch of an AC line on a new energy single-line transmission system based on new control parameters;

[0091] A data recording module, used for recording the first new energy output and the second new energy output of the system when the single-line new energy transmission system reaches a critical stable state at a single instantaneous fault critical stability;

[0092] The transmission limit improvement module is used to compare the first new energy output and the second new energy output. If the second new energy output is greater than the first new energy output, the new energy single-line transmission system is controlled after a fault with new control parameters to improve the transmission limit of the new energy single-line transmission system.

[0093] In one embodiment, a single-phase instantaneous ground reclosing failure scanning is performed on a new energy single-line transmission system, including:

[0094] Based on the set initial active power of new energy, the single-line transmission system of new energy is scanned for successful faults of single-phase instantaneous grounding reclosing of AC line;

[0095] Determine whether the new energy single-line transmission system has reached a critical stable state;

[0096] If not, the active power of renewable energy is increased according to the set step size until the system reaches a critical stable state.

[0097] In one embodiment, the critical stable state includes: a critical state when the system is unstable and a critical state when the new energy source is running at full power.

[0098] In one embodiment, the control parameters include at least: a low voltage active power control value, an initial value of active power ramping after a fault, a maintenance time of the initial value of active power ramping after a fault, and an active power ramping rate after a fault.

[0099] In one embodiment, when setting control parameters of the new energy single-line transmission system during low voltage ride-through and post-fault recovery, the maintenance time of the initial value of active power ramp after the fault is set to zero.

[0100] Those skilled in the art can clearly understand that, for the convenience and simplicity of description, only the division of the above-mentioned functional units and modules is used as an example for illustration. In practical applications, the above-mentioned function allocation can be completed by different functional units and modules as needed, that is, the internal structure of the system can be divided into different functional units or modules to complete all or part of the functions described above. The functional units and modules in the embodiment can be integrated in a processing unit, or each unit can exist physically separately, or two or more units can be integrated in one unit. The above-mentioned integrated unit can be implemented in the form of hardware or in the form of software functional units. In addition, the specific names of the functional units and modules are only for the convenience of distinguishing each other, and are not used to limit the scope of protection of this application. The specific working process of the units and modules in the above-mentioned system can refer to the corresponding process in the aforementioned method embodiment, which will not be repeated here.

[0101] An embodiment of the present invention also provides a computer device, comprising: a memory and a processor and a computer program stored in the memory. When the computer program is executed on the processor, a method for improving the delivery limit of a new energy single-line delivery system as described in any one of the above methods is implemented.

[0102] The computer device may be a desktop computer, a notebook computer, a palm computer, a cloud server, etc. The computer device may include, but is not limited to, a processor and a memory.

[0103] The processor may be a central processing unit (CPU), other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general-purpose processor may be a microprocessor or any conventional processor, etc.

[0104] In some embodiments, the memory may be an internal storage unit of the computer device, such as a hard disk or memory of the computer device. In other embodiments, the memory may also be an external storage device of the computer device, such as a plug-in hard disk, a smart media card (SMC), a secure digital (SD) card, a flash card, etc. equipped on the computer device. Further, the memory may include both an internal storage unit and an external storage device of the computer device. The memory is used to store an operating system, an application program, a boot loader (BootLoader), data, and other programs, such as the program code of the computer program. The memory may also be used to temporarily store data that has been output or is to be output.

[0105] An embodiment of the present invention further provides a computer-readable storage medium having a computer program stored thereon. When the computer program is executed by a processor, the method for improving the delivery limit of a new energy single-line delivery system as described in any one of the above methods is implemented.

[0106] In this embodiment, if the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the present application implements all or part of the processes in the above-mentioned embodiment method, which can be completed by instructing the relevant hardware through a computer program. The computer program can be stored in a computer-readable storage medium. When the computer program is executed by the processor, the steps of the above-mentioned various method embodiments can be implemented. Among them, the computer program includes computer program code, and the computer program code can be in source code form, object code form, executable file or some intermediate form. The computer-readable medium can at least include: any entity or device that can carry the computer program code to the camera / terminal device, recording medium, computer memory, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), electric carrier signal, telecommunication signal and software distribution medium. For example, USB flash drive, mobile hard disk, disk or optical disk. In some jurisdictions, according to legislation and patent practice, computer-readable media cannot be electric carrier signals and telecommunication signals.

[0107] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described or recorded in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0108] Those of ordinary skill in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of this application.

[0109] In the embodiments disclosed in the present application, it should be understood that the disclosed devices / terminal equipment and methods can be implemented in other ways. For example, the device / terminal equipment embodiments described above are only schematic. For example, the division of the modules or units is only a logical function division. There may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0110] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for improving the delivery limit of a new energy single-line delivery system, characterized in that: The steps include: Set the control parameters of the new energy single-line transmission system during low voltage ride-through and post-fault recovery; Based on the control parameters, a successful fault scan of single-phase instantaneous ground reclosing of the AC line is performed on the new energy single-line transmission system; When the new energy single-line transmission system reaches a critical stable state, the first new energy output of the system is recorded when the system is critically stable under a single instantaneous fault; The maintenance time of the initial value of active power ramp after a fault is set in the control parameter to obtain a new control parameter; Based on the new control parameters, re-scanning the AC line single-phase instantaneous ground reclosing success fault of the new energy single-line transmission system; When the new energy single-line transmission system reaches a critical stable state, the second new energy output of the system is recorded when the system is critically stable under a single instantaneous fault; The first new energy output and the second new energy output are compared. If the second new energy output is greater than the first new energy output, the new control parameters are used to perform post-fault control on the new energy single-line transmission system to increase the transmission limit of the new energy single-line transmission system.

2. The method for improving the delivery limit of a new energy single-line delivery system according to claim 1 is characterized in that: The single-phase instantaneous ground reclosing failure scanning of the AC line of the new energy single-line transmission system is successfully performed, including: Based on the set initial active power of the new energy, a single-phase instantaneous ground reclosing successful fault scan of the AC line is performed on the new energy single-line transmission system; Determining whether the new energy single-line transmission system has reached a critical stable state; If not, the active power of renewable energy is increased according to the set step size until the system reaches a critical stable state.

3. The method for improving the delivery limit of a new energy single-line delivery system according to claim 2 is characterized in that: The critical stable state includes: a critical state when the system is unstable and a critical state when the new energy is running at full power.

4. The method for improving the delivery limit of a new energy single-line delivery system according to claim 1 is characterized in that: The control parameters include at least: a low voltage active power control value, an initial value of active power climbing after a fault, a maintenance time of the initial value of active power climbing after a fault, and an active power climbing rate after a fault.

5. The method for improving the delivery limit of a new energy single-line delivery system according to claim 4 is characterized in that: When setting the control parameters of the new energy single-line transmission system during low voltage ride-through and post-fault recovery, the maintenance time of the initial value of the active power ramp after the fault is set to zero.

6. A device for increasing the delivery limit of a new energy single-line delivery system, characterized in that: include: The parameter setting module is used to set the control parameters of the new energy single-line transmission system during low voltage ride-through and post-fault recovery; It is also used to set the maintenance time of the initial value of active power climbing after a fault in the control parameter to obtain a new control parameter; A fault scanning module is used to perform a successful fault scan of a single-phase instantaneous ground reclosing switch of an AC line on the new energy single-line transmission system based on the control parameters; and is also used to perform a successful fault scan of a single-phase instantaneous ground reclosing switch of an AC line on the new energy single-line transmission system based on the new control parameters; A data recording module, used for recording the first new energy output and the second new energy output of the system when the new energy single-line transmission system reaches a critical stable state when a single-momentary fault is critically stable; The transmission limit improvement module is used to compare the first new energy output and the second new energy output. If the second new energy output is greater than the first new energy output, the new control parameters are used to perform post-fault control on the new energy single-line transmission system to improve the transmission limit of the new energy single-line transmission system.

7. The device for increasing the delivery limit of a new energy single-line delivery system according to claim 6 is characterized in that: The single-phase instantaneous ground reclosing failure scanning of the AC line of the new energy single-line transmission system is successfully performed, including: Based on the set initial active power of the new energy, a single-phase instantaneous ground reclosing successful fault scan of the AC line is performed on the new energy single-line transmission system; Determining whether the new energy single-line transmission system has reached a critical stable state; If not, the active power of renewable energy is increased according to the set step size until the system reaches a critical stable state.

8. The device for increasing the delivery limit of a new energy single-line delivery system according to claim 7 is characterized in that: The critical stable state includes: a critical state when the system is unstable and a critical state when the new energy is running at full power.

9. The device for increasing the delivery limit of a new energy single-line delivery system according to claim 6 is characterized in that: The control parameters include at least: a low voltage active power control value, an initial value of active power climbing after a fault, a maintenance time of the initial value of active power climbing after a fault, and an active power climbing rate after a fault.

10. The device for increasing the delivery limit of a new energy single-line delivery system according to claim 9 is characterized in that: When setting the control parameters of the new energy single-line transmission system during low voltage ride-through and post-fault recovery, the maintenance time of the initial value of the active power ramp after the fault is set to zero.

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