A quantitative evaluation method and related device for system reactive power reserve margin

Abstract

The present invention provides a quantitative assessment method and related device for the reactive reserve margin of a system, including performing time domain simulation of the system according to a set system mode and fault, detecting the weakest point of transient voltage; adding a virtual standard reactive source at the weakest point of transient voltage; re-performing time domain simulation, and after the system fault is cleared, inputting the standard reactive source in a specific manner, and judging whether the system has critical transient voltage stability; if not, adjusting the maximum current value, and re-performing time domain simulation; if so, using the reactive power corresponding to the maximum current value when the system has critical transient voltage stability as the reactive reserve margin under the set system mode and fault. The reactive reserve margin determined by the present invention can be used to quantitatively assess the balance between the reactive reserve and reactive demand of the system, and can also provide a theoretical basis for optimizing the excitation control parameters of the generator and the operation and control of the receiving power grid.

Description

Technical Field

[0001] The present invention belongs to the technical field of power system safety and stability analysis, and in particular relates to a quantitative evaluation method and related device for system reactive power reserve margin. Background Art

[0002] With the increasing number of DC transmission lines and their centralized feed-in to load centers, the reactive power characteristics of receiving-end power systems undergo complex changes when subjected to severe faults such as short circuits. On the one hand, power transfer leads to a significant increase in reactive power losses in the AC channel; on the other hand, reactive power consumption in DC converter stations and asynchronous motor loads rises sharply during faults. These factors combine to significantly alter the system's reactive power flow. During the transient state following a fault, reactive power and voltage interact and constrain each other. The dynamic response characteristics of the reactive power source largely determine the system's transient voltage stability. If dynamic reactive power reserves are insufficient, the system is likely to experience prolonged and deep voltage dips, leading to transient voltage instability. This poses a serious threat to the safe and reliable operation of the power system and may even cause widespread power outages, resulting in significant socioeconomic losses. Therefore, in-depth research on system reactive power reserves and accurate assessment of their adequacy are crucial for ensuring stable power system operation.

[0003] At present, although there have been some relevant research and technical means in the field of reactive power reserve assessment in power systems, there are still many shortcomings. Traditional assessment methods often lack the ability to accurately quantify the dynamic balance between reactive power reserve and reactive power demand under complex fault conditions. Some methods rely too much on empirical models or simplified calculations, and cannot fully consider the impact of complex real-world situations such as multiple DC drop points, different types of loads, and multiple fault combinations on reactive power reserves. In addition, existing technologies are clearly lacking in providing an accurate and effective theoretical basis for optimizing generator excitation control parameters and receiving-end grid operation control, making it difficult to meet the strict requirements of modern power systems for high safety, stability, and the ability to withstand serious fault risks. This urgently requires a more scientific, comprehensive, and accurate quantitative assessment method for system reactive power reserve adequacy to fill the gaps in existing technologies, effectively solve the reactive power reserve-related problems facing current power systems, and promote the sustainable development of the power industry. Summary of the Invention

[0004] In view of this, the present invention provides a quantitative assessment method and related device for the system reactive reserve margin, so as to accurately quantify the balance relationship between the system reactive reserve and reactive demand, provide theoretical support for optimizing the generator excitation control parameters and the operation and control of the receiving-end power grid, and improve the safe and stable operation level of the DC multi-point receiving-end system and its ability to resist the risk of serious AC faults.

[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 quantitatively evaluating the reactive power reserve adequacy of a system, comprising the following steps:

[0007] Perform time domain simulation of the system according to the set system mode and faults to detect the weakest point of transient voltage;

[0008] A virtual standard reactive power source is added at the weakest point of transient voltage; the maximum current of the standard reactive power source is determined by the voltage difference between the weakest point of transient voltage and the critical transient voltage stability point;

[0009] Re-run the time domain simulation, and after the system fault is cleared, put the standard reactive power source into operation in a specific manner, and determine whether the system has critical transient voltage stability;

[0010] If not, adjust the maximum current value and re-perform the time domain simulation;

[0011] If so, the reactive power corresponding to the maximum current value when the system experiences critical transient voltage stability is used as the reactive power reserve margin under the set system mode and fault conditions.

[0012] Furthermore, a virtual standard reactive power source is added at the weakest point of transient voltage, including:

[0013] When the system is in the initial transient voltage stability, the maximum current is set to inductive;

[0014] When the system is in the initial transient voltage instability, the maximum current is set to capacitive.

[0015] Furthermore, the specific method is:

[0016] The input process is simulated as a first-order low-pass filtering process that tracks the maximum current of the standard reactive power source.

[0017] Furthermore, the reactive power is calculated as follows:

[0018] Q = U E *I C

[0019] Where Q is reactive power, and a negative value indicates insufficient reactive power reserve. E is the critical voltage, I C is the maximum current value.

[0020] In a second aspect, the present invention provides a device for quantitatively evaluating system reactive power reserve adequacy, comprising:

[0021] The simulation module is used to perform time-domain simulation of the system according to the set system mode and fault, and detect the weakest point of transient voltage. It is also used to add a virtual standard reactive power source at the weakest point of transient voltage. The maximum current of the standard reactive power source is determined by the voltage difference between the weakest point of transient voltage and the critical transient voltage stability point. It is also used to re-perform time-domain simulation and, after the system fault is cleared, to add the standard reactive power source according to a specific method and determine whether the system has experienced critical transient voltage stability.

[0022] The reactive power judgment module is used to adjust the maximum current value and re-perform time domain simulation through the simulation module when the system does not experience critical transient voltage stability. It is also used to use the reactive power corresponding to the maximum current value as the reactive power reserve margin under the setting system mode and fault conditions when the system experiences critical transient voltage stability.

[0023] Furthermore, a virtual standard reactive power source is added at the weakest point of transient voltage, including:

[0024] When the system is in the initial transient voltage stability, the maximum current is set to inductive;

[0025] When the system is in the initial transient voltage instability, the maximum current is set to capacitive.

[0026] Furthermore, the specific method is:

[0027] The input process is simulated as a first-order low-pass filtering process that tracks the maximum current of the standard reactive power source.

[0028] Furthermore, the reactive power is calculated as follows:

[0029] Q = U E *I C

[0030] Where Q is reactive power, and a negative value indicates insufficient reactive power reserve. E is the critical voltage, I C is the maximum current value.

[0031] In a third aspect, the present invention provides a computer device, comprising a processor and a memory:

[0032] The memory is used to store computer programs and send instructions of the computer programs to the processor;

[0033] The processor executes the quantitative evaluation method for system reactive power reserve margin according to the instructions of the computer program as described in the first aspect.

[0034] In a fourth aspect, the present invention provides a computer-readable storage medium having a computer program stored thereon. When the computer program is executed by a processor, a quantitative evaluation method for system reactive power reserve adequacy as in the first aspect is implemented.

[0035] In summary, the present invention provides a quantitative assessment method and related device for the system reactive reserve margin, including performing time domain simulation on the system according to the set system mode and fault, detecting the weakest point of transient voltage; adding a virtual standard reactive source at the weakest point of transient voltage; the maximum current of the standard reactive source is determined according to the voltage difference between the weakest point of transient voltage and the critical transient voltage stability; re-performing time domain simulation, and after the system fault is cleared, putting the standard reactive source into operation in a specific manner, and judging whether the system has critical transient voltage stability; if not, adjusting the maximum current value, and re-performing time domain simulation; if so, taking the reactive power corresponding to the maximum current value when the system has critical transient voltage stability as the reactive reserve margin under the set system mode and fault. The reactive reserve margin quantified by the present invention can be used to quantitatively assess the balance between the reactive reserve and reactive demand of the system, and can also provide a theoretical basis for optimizing the excitation control parameters of the generator and the operation and control of the receiving power grid, thereby further improving the safe and stable operation level of the DC multi-drop receiving system and its ability to resist the risk of serious AC faults. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. 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 any creative work.

[0037] Figure 1 A flowchart of a method for quantitatively evaluating system reactive power reserve adequacy provided by one embodiment of the present invention;

[0038] Figure 2 A flowchart of a method for quantitatively evaluating system reactive power reserve margin provided by another embodiment of the present invention;

[0039] Figure 3 A block diagram of a device for quantitatively evaluating system reactive power reserve margin provided by another embodiment of the present invention;

[0040] Figure 4 A block diagram of a computer device according to another embodiment of the present invention. DETAILED DESCRIPTION

[0041] In order to make the purposes, 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 making creative work are within the scope of protection of the present invention.

[0042] See also Figure 1 The embodiment of the present invention provides a quantitative evaluation method for system reactive power reserve adequacy, comprising the following steps:

[0043] S1: Perform time domain simulation of the system according to the set system mode and fault to detect the weakest point of transient voltage.

[0044] It's important to note that time-domain simulation is a method for simulating and analyzing the dynamic behavior of a system within the time domain. In power systems, this involves building a mathematical model of the system, considering the electrical characteristics of various components (such as generators, transformers, lines, and loads) and their interconnections. The system's state variables (such as voltage, current, and power) are then calculated over time at different moments in time to simulate the system's actual operation under set operating conditions (such as fault occurrence and fault clearance).

[0045] During a power system fault and subsequent recovery, voltage fluctuations occur at different locations. The transient voltage vulnerability point refers to the specific location in the system where the voltage drops the most during the fault and the period following it (the transient process), making it the most susceptible to voltage instability.

[0046] This step uses time-domain simulation based on the set system mode (such as the system's operating mode and network topology) and fault conditions to fully and accurately simulate the system's operating state under actual operating conditions, thereby identifying the weakest point in transient voltage. This provides a foundation for subsequent targeted analysis and resolution of reactive power reserve issues at these weak points.

[0047] S2: Add a virtual standard reactive power source at the weakest point of transient voltage; the maximum current of the standard reactive power source is determined by the voltage difference between the weakest point of transient voltage and the critical transient voltage stability point.

[0048] It should be noted that a virtual standard reactive power source is a reactive power source with standard characteristics that is added during the simulation analysis. It outputs reactive power according to predefined rules and is used to analyze the impact of adding reactive power compensation at specific locations on system transient voltage stability.

[0049] This step determines the maximum current of the standard reactive power source based on the voltage difference between the weakest transient voltage point and the critical transient voltage stability state. A large voltage difference at this point indicates a greater amount of reactive power compensation is needed to improve voltage stability, and the determined maximum current will be correspondingly larger; otherwise, the maximum current will be smaller. Furthermore, the initial nature of the maximum current (inductive or capacitive) is determined based on whether the system's initial transient voltage is stable. This is based on the different characteristics of inductive and capacitive reactive power's impact on voltage (inductive reactive power can indicate a surplus of reactive power reserves in certain circumstances, while capacitive reactive power is used when reactive power supplementation is needed).

[0050] S3: Re-perform the time domain simulation, and after the system fault is cleared, put the standard reactive power source into operation in a specific manner, and determine whether the system has critical transient voltage stability.

[0051] It should be noted that critical transient voltage stability refers to the situation where the voltage of the power system is in a critical state during the transient process after a fault. That is, even a slight adverse impact (such as insufficient reactive power reserve) may lead to voltage instability (the voltage drops sharply and cannot return to the normal operating range). However, if the current reactive power balance and other conditions can be maintained, the system can maintain stable operation.

[0052] In this step, in the new system state after the fault is cleared, the reactive power source is put into operation in a specific manner that conforms to the gradual change characteristics of the actual reactive power source. Then, the voltage and other state variables of each point in the system are calculated through time domain simulation. By observing the voltage changes and comparing them with the critical transient voltage stability state, it is determined whether the system has reached the critical transient voltage stability.

[0053] S4: If not, adjust the maximum current value and perform time domain simulation again.

[0054] It should be noted that based on the latest status of system voltage and other state variables obtained from the previous round of time-domain simulation, the degree of current reactive power compensation deficiency or excess is analyzed, and then the maximum current of the standard reactive power source is reasonably adjusted (such as increasing or decreasing the current value, or changing its inductive / capacitive properties). Then, the time-domain simulation is repeated according to step S3 to continue to observe whether the system can achieve critical transient voltage stability.

[0055] S5: If yes, the reactive power corresponding to the maximum current value when the system has critical transient voltage stability is used as the reactive power reserve margin under the set system mode and fault conditions.

[0056] It should be noted that when the system experiences critical transient voltage stabilization, the reactive power corresponding to the maximum current at that moment is used as the reactive power reserve margin for setting the system mode and under fault conditions. This enables a quantitative assessment of the system's reactive power reserve margin under specific operating conditions, providing specific data for subsequent judgments on the adequacy of the system's reactive power reserve and the need for further optimization.

[0057] This embodiment provides a quantitative assessment method for the reactive power reserve margin of a system. First, through time-domain simulation, the weakest transient voltage point of the system under set operating conditions is identified. A virtual standard reactive power source is then added to this weak point. By continuously adjusting its maximum current, the reactive power source is added in a specific manner and time-domain simulation is repeated to observe whether the system achieves critical transient voltage stability. Through this repeated adjustment and observation process, the maximum current that enables the system to achieve critical transient voltage stability is ultimately found. Based on this maximum current, the corresponding reactive power value is calculated, which serves as the reactive power reserve margin of the system under the set system mode and fault conditions. The core implementation principle is based on a deep understanding of the interplay between reactive power and voltage during a power system fault and subsequent recovery. The reactive power reserve margin of the system is quantitatively assessed by simulating and adjusting reactive compensation. This method does not perform a general reactive power reserve assessment of the entire system. Instead, it first precisely locates the weakest transient voltage point and then performs subsequent reactive compensation analysis and assessment on this weak point. This method more accurately determines the reactive power reserve required by the system under specific operating conditions, improving the pertinence and accuracy of the assessment.

[0058] In one embodiment, adding a virtual standard reactive power source at the weakest point of transient voltage further includes:

[0059] When the system is in the initial transient voltage stability, the maximum current is set to inductive;

[0060] When the system is in the initial transient voltage instability, the maximum current is set to capacitive.

[0061] Inductive reactive power is primarily generated by inductive components. In AC circuits, inductive current lags behind voltage. When the system's initial transient voltage stabilizes, setting the maximum current to an inductive (positive) value indicates that the system's dynamic reactive power reserve exceeds the reactive power demand. Inductive reactive power can, to a certain extent, help maintain voltage stability or even increase it.

[0062] Capacitive reactive power is primarily generated by capacitors, with the capacitive current leading the voltage. When the system experiences initial transient voltage instability, such as voltage sags, capacitive reactive power is needed to boost the voltage. Therefore, the maximum current is set to a capacitive (negative) value. This is because capacitive reactive power can compensate for inductive reactive power in the system, quickly providing reactive power to support voltage recovery.

[0063] This method of setting the maximum current (IC) attribute based on the stability of the system's initial transient voltage is a key component of the overall quantitative assessment of reactive power reserve adequacy. It provides reasonable initial conditions for subsequently adjusting the output of the virtual standard reactive power source and observing the system's reactive power-voltage dynamics.

[0064] When I C When it is inductive (positive value), it means that the system is in a good reactive reserve state at the beginning. In the subsequent time domain simulation, the voltage stability changes of the system under different reactive reserve levels can be observed by appropriately adjusting the size of this inductive reactive power. C When the value is capacitive (negative), it indicates that the system has already experienced transient voltage instability. From the outset, it is determined that capacitive reactive power needs to be added to improve voltage stability. Subsequent adjustments are made to determine the appropriate amount of capacitive reactive power compensation to achieve critical transient voltage stability. This setup allows for more accurate simulation and analysis of the system's reactive power reserve requirements under different initial conditions, leading to a more effective assessment of the system's reactive power reserve adequacy.

[0065] In one embodiment, a specific approach is to simulate the switching-on process as a first-order low-pass filtering process that tracks the maximum current value of a standard reactive power source.

[0066] In this embodiment, the standard reactive power source's input process is simulated as a first-order low-pass filtering process. When the reactive power source is applied, its input does not instantly reach its maximum value. Instead, it gradually reaches its maximum value, similar to how a first-order low-pass filter processes its input signal. This is similar to how a first-order low-pass filter processes its input signal: after the input signal (corresponding to the reactive power source input) undergoes a time-dependent "processing process," the output (the actual reactive power input to the system) gradually reaches a stable value.

[0067] The maximum current of the standard reactive power source is a parameter closely related to the assessment of the system's reactive power reserve adequacy. In the previous step, the maximum current of the standard reactive power source was determined by identifying the weakest transient voltage point and the voltage difference between it and the critical transient voltage stability point. This maximum current represents the maximum current the reactive power source must output to achieve critical transient voltage stability. Its magnitude reflects the amount of reactive power compensation required by the system under specific operating conditions.

[0068] This method of simulating the input process as a first-order low-pass filtering process that tracks the maximum current of the standard reactive source is more consistent with the physical characteristics of reactive source input in actual power systems.

[0069] In one embodiment, reactive power is calculated as follows:

[0070] Q = U E *I C

[0071] Where Q is reactive power, and a negative value indicates insufficient reactive power reserve. E is the critical voltage, I C is the maximum current value.

[0072] Figure 2 This is a process flow of a quantitative evaluation method for a system reactive power reserve margin obtained by combining the specific input mode and reactive power calculation proposed in the above embodiment.

[0073] Based on the same inventive concept, an embodiment of the present application further provides a device for quantitatively assessing system reactive power reserve margin, which is used to implement the aforementioned method for quantitatively assessing system reactive power reserve margin. The solution provided by this device is similar to the solution described in the aforementioned method. Therefore, the specific limitations of the embodiment of the device for quantitatively assessing system reactive power reserve margin provided below can be found in the aforementioned limitations of the method for quantitatively assessing system reactive power reserve margin, and will not be further elaborated here.

[0074] See also Figure 3 The embodiment of the present invention provides a device for quantitatively evaluating the reactive power reserve margin of a system, comprising:

[0075] The simulation module is used to perform time-domain simulation of the system according to the set system mode and fault, and detect the weakest point of transient voltage. It is also used to add a virtual standard reactive power source at the weakest point of transient voltage. The maximum current of the standard reactive power source is determined by the voltage difference between the weakest point of transient voltage and the critical transient voltage stability point. It is also used to re-perform time-domain simulation and, after the system fault is cleared, to add the standard reactive power source according to a specific method and determine whether the system has experienced critical transient voltage stability.

[0076] The reactive power judgment module is used to adjust the maximum current value and re-perform time domain simulation through the simulation module when the system does not experience critical transient voltage stability. It is also used to use the reactive power corresponding to the maximum current value as the reactive power reserve margin under the setting system mode and fault conditions when the system experiences critical transient voltage stability.

[0077] Furthermore, a virtual standard reactive power source is added at the weakest point of transient voltage, including:

[0078] When the system is in the initial transient voltage stability, the maximum current is set to inductive;

[0079] When the system is in the initial transient voltage instability, the maximum current is set to capacitive.

[0080] Furthermore, the specific method is:

[0081] The input process is simulated as a first-order low-pass filtering process that tracks the maximum current of the standard reactive power source.

[0082] Furthermore, the reactive power is calculated as follows:

[0083] Q = U E *I C

[0084] Where Q is reactive power, and a negative value indicates insufficient reactive power reserve. E is the critical voltage, I C is the maximum current value.

[0085] Those skilled in the art can clearly understand that, for the convenience and brevity of description, only the division of the above-mentioned functional units and modules is used as an example for illustration. In actual applications, the above-mentioned functions can be distributed and 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 into one processing unit, or each unit can exist physically alone, or two or more units can be integrated into 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, and will not be repeated here.

[0086] Reference Figure 4 An embodiment of the present invention further 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, it implements the quantitative evaluation method of the system reactive power reserve margin as described in any one of the above methods.

[0087] The computer device may be a desktop computer, notebook computer, PDA, cloud server or other computing device. The computer device may include, but is not limited to, a processor and a memory. It will be understood by those skilled in the art that Figure 4 This is merely an example of a computer device and does not constitute a limitation on the computer device. The computer device may include more or fewer components than shown in the figure, or a combination of certain components, or different components. For example, it may also include input and output devices, network access devices, etc.

[0088] 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), 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.

[0089] In some embodiments, the memory may be an internal storage unit of the computer device, such as a hard drive 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 drive, a Smart Media Card (SMC), a Secure Digital (SD) card, a flash memory card, etc. equipped with the computer device. Furthermore, the memory may include both an internal storage unit of the computer device and an external storage device. The memory is used to store an operating system, application programs, a boot loader, 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 about to be output.

[0090] 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 quantitatively evaluating the system reactive power reserve adequacy as described in any one of the above methods is implemented.

[0091] In this embodiment, if the integrated unit is implemented as a software functional unit and sold or used as a standalone product, it can be stored in a computer-readable storage medium. Based on this understanding, the present application can implement all or part of the process steps in the above-mentioned method embodiments by using a computer program to instruct the relevant hardware. The computer program can be stored in a computer-readable storage medium. When executed by a processor, the computer program can implement the steps of each of the above-mentioned method embodiments. The computer program includes computer program code, which can be in source code form, object code form, executable file, or some intermediate form. The computer-readable medium can include at least: any entity or device capable of carrying computer program code to a camera / terminal device, recording medium, computer memory, read-only memory (ROM), random access memory (RAM), electric carrier signals, telecommunication signals, and software distribution media. Examples include USB flash drives, removable hard drives, magnetic disks, or optical disks. In some jurisdictions, based on legislation and patent practice, computer-readable media cannot be electric carrier signals or telecommunication signals.

[0092] An embodiment of the present invention provides a computer program product, including a computer program. When the computer program is executed by a processor, the computer program implements the quantitative evaluation method for system reactive power reserve adequacy as described in any one of the above methods.

[0093] In the above embodiments, the description of each embodiment has its own focus. For parts that are not described or recorded in detail in a certain embodiment, reference can be made to the relevant description of other embodiments.

[0094] Those skilled 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 beyond the scope of this application.

[0095] 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 merely schematic. For example, the division of the modules or units is merely a logical function division. In actual implementation, there may be other division methods, 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.

[0096] 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 they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. 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 various embodiments of the present invention.

Claims

1. A quantitative evaluation method for system reactive power reserve adequacy, characterized in that: The steps include: Perform time domain simulation of the system according to the set system mode and faults to detect the weakest point of transient voltage; Adding a virtual standard reactive power source at the weakest point of the transient voltage; The maximum current of the standard reactive power source is determined according to the voltage difference between the weakest point of the transient voltage and the critical transient voltage stability point; Re-perform the time domain simulation, and after the system fault is cleared, put the standard reactive power source into operation in a specific manner, and determine whether the system has critical transient voltage stability; If not, adjust the maximum current value and re-perform the time domain simulation; If so, the reactive power corresponding to the maximum current value when the system has critical transient voltage stability is used as the reactive power reserve margin under the setting system mode and fault.

2. The quantitative evaluation method for system reactive power reserve margin according to claim 1, characterized in that: Adding a virtual standard reactive power source at the weakest point of the transient voltage, further comprising: When the system is in an initial transient voltage stable state, the maximum current value is set to inductive; When the system is in an initial transient voltage instability, the maximum current value is set to capacitive.

3. The quantitative evaluation method for system reactive power reserve margin according to claim 1, characterized in that: The specific method is: The switching process is simulated as a first-order low-pass filtering process that tracks the maximum current of the standard reactive power source.

4. The quantitative evaluation method for system reactive power reserve margin according to claim 1, characterized in that: The reactive power is calculated according to the following formula: Q = U E *I C Where Q is the reactive power, and a negative value indicates insufficient reactive power reserve. E is the critical voltage, I C is the maximum current value.

5. A quantitative evaluation device for system reactive power reserve margin, characterized in that: include: The simulation module is used to simulate the system in the time domain according to the set system mode and faults, and detect the weakest point of transient voltage; It is also used to add a virtual standard reactive power source at the weakest point of the transient voltage; the maximum current of the standard reactive power source is determined according to the voltage difference between the weakest point of the transient voltage and the critical transient voltage stability point; it is also used to re-perform the time domain simulation, and after the system fault is cleared, put the standard reactive power source into use in a specific manner, and determine whether the system has a critical transient voltage stability; The reactive power judgment module is used to adjust the maximum current value and re-perform time domain simulation through the simulation module when the system does not have critical transient voltage stability; it is also used to use the reactive power corresponding to the maximum current value as the reactive reserve margin under the setting system mode and fault when the system has critical transient voltage stability.

6. The quantitative evaluation device for system reactive power reserve margin according to claim 5, characterized in that: Adding a virtual standard reactive power source at the weakest point of the transient voltage, further comprising: When the system is in an initial transient voltage stable state, the maximum current value is set to inductive; When the system is in an initial transient voltage instability, the maximum current value is set to capacitive.

7. The quantitative evaluation device for system reactive power reserve margin according to claim 5, characterized in that: The specific method is: The switching process is simulated as a first-order low-pass filtering process that tracks the maximum current of the standard reactive power source.

8. The quantitative evaluation device for system reactive power reserve margin according to claim 5, characterized in that: The reactive power is calculated according to the following formula: Q = U E *I C Where Q is the reactive power, and a negative value indicates insufficient reactive power reserve. E is the critical voltage, I C is the maximum current value.

9. A computer device, characterized in that: The device includes a processor and a memory: The memory is used to store the computer program and send instructions of the computer program to the processor; The processor executes the method for quantitatively evaluating system reactive power reserve adequacy according to any one of claims 1 to 4 according to the instructions of the computer program.

10. A computer-readable storage medium, characterized in that The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the method for quantitatively evaluating system reactive power reserve adequacy according to any one of claims 1 to 4 is implemented.

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