Method, device and equipment for evaluating inertia and primary frequency modulation capability of power supply node

Abstract

Embodiments of the present disclosure provide a method, device and equipment for evaluating inertia and primary frequency modulation capability of a power supply node. The method comprises injecting a small disturbance power into a power system and calculating impedance at each power supply node in the power system; drawing an amplitude response curve corresponding to a frequency response transfer function according to the impedance at the power supply node and a frequency response transfer function formula at the power supply node; and calculating inertia coefficients and primary frequency modulation capability coefficients of each power supply node according to each amplitude response curve. In this way, the inertia coefficients and the primary frequency modulation capability coefficients of each power supply node can be calculated in real time from the perspective of impedance under the premise of ensuring normal operation of the power system, and the inertia and the primary frequency modulation capability of the power supply node can be quickly and accurately evaluated.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to the technical field of power systems, and particularly relates to a method, device and equipment for evaluating inertia and primary frequency regulation capability of a power supply node. BACKGROUND

[0002] In order to accelerate the transition to a low-carbon or carbon-neutral energy economy, more and more fossil fuel combustion units (FFUs) are being replaced by renewable generator units (RGUs). Most RGUs are connected to the power system through a power electronic interface (i.e., an inverter), and thus do not provide inherent inertia and effective frequency support after power disturbance, resulting in a decrease in system inertia level and primary frequency regulation (PFR) capability, which brings unprecedented challenges to the safe and stable operation of the power system.

[0003] In recent years, extensive research has been conducted on methods for evaluating the inertia and primary frequency regulation capability of power supply nodes in power systems. These methods can be divided into two categories: offline evaluation and online evaluation. Offline evaluation mainly relies on offline evaluation of large disturbance events, and online evaluation is mainly based on online system evaluation of PMU measurement data. However, the above methods generally have low precision and poor efficiency, and thus how to quickly and accurately evaluate the inertia and primary frequency regulation capability of power supply nodes has become a problem that needs to be solved. SUMMARY

[0004] The present disclosure provides a method, device, equipment and storage medium for evaluating the inertia and primary frequency regulation capability of a power supply node, which can quickly and accurately evaluate the inertia and primary frequency regulation capability of the power supply node.

[0005] In a first aspect, the embodiments of the present disclosure provide a method for evaluating the inertia and primary frequency regulation capability of a power supply node, which comprises:

[0006] injecting a small disturbance power into the power system, and calculating the impedance at each power supply node in the power system;

[0007] drawing an amplitude response curve corresponding to a frequency response transfer function according to the impedance at the power supply node and the frequency response transfer function formula at the power supply node;

[0008] calculating the inertia coefficient and the primary frequency regulation capability coefficient of each power supply node according to each amplitude response curve.

[0009] In some implementable manners of the first aspect, the small disturbance power is a sinusoidal active power.

[0010] In some implementable manners of the first aspect, the amplitude response curve corresponding to the frequency response transfer function is plotted according to the impedance at the power supply node and a formula of the frequency response transfer function at the power supply node, including:

[0011] The coupling impedance at the power supply node is calculated according to the impedance at the power supply node;

[0012] The amplitude response curve corresponding to the frequency response transfer function is plotted according to the coupling impedance at the power supply node and the formula of the frequency response transfer function at the power supply node.

[0013] In some implementable manners of the first aspect,

[0014] The formula of the frequency response transfer function at the power supply node is:

[0015]

[0016] Wherein, FR(s) represents the frequency response transfer function, represents the coupling impedance at the power supply node, u sd0 represents the real-time voltage at the power supply node, V s represents the reference voltage at the power supply node, f represents the real-time frequency at the power supply node, f B_PLL represents the phase-locked loop bandwidth.

[0017] In some implementable manners of the first aspect, the inertia coefficient and the primary frequency modulation capability coefficient of each power supply node are calculated according to the amplitude response curves, including:

[0018] The resonance frequency and the direct current gain are extracted from the amplitude response curve;

[0019] The inertia coefficient of the power supply node is calculated according to the extracted resonance frequency;

[0020] The primary frequency modulation capability coefficient of the power supply node is calculated according to the extracted direct current gain.

[0021] In some implementable manners of the first aspect, the inertia coefficient of the power supply node is calculated according to the extracted resonance frequency, including:

[0022] The inertia coefficient of the power supply node is calculated according to the extracted resonance frequency and a formula of the inertia coefficient, the formula of the inertia coefficient being:

[0023]

[0024] Wherein, H n represents the inertia coefficient of the power supply node, ω H is the extracted resonance frequency, L eq is the equivalent inductance of the power grid transmission line.

[0025] In some possible implementation manners of the first aspect, the calculating the primary frequency modulation capability coefficient of the power supply node according to the extracted direct current gain comprises:

[0026] The primary frequency modulation capability coefficient of the power supply node is calculated according to the extracted direct current gain and a primary frequency modulation capability coefficient formula, where the primary frequency modulation capability coefficient formula is:

[0027]

[0028] where K n represents the primary frequency modulation capability coefficient of the power supply node, R n represents the resistance at the power supply node, f0 represents the reference frequency at the power supply node, S n represents the nominal power capacity of the generator corresponding to the power supply node, and represents the extracted direct current gain.

[0029] In the second aspect, the embodiments of the present disclosure provide a device for evaluating the inertia and the primary frequency modulation capability of a power supply node, and the device comprises:

[0030] A calculation module is configured to inject a small disturbance power into a power system, and calculate the impedance at each power supply node in the power system.

[0031] A drawing module is configured to draw an amplitude response curve corresponding to a frequency response transfer function according to the impedance at the power supply node and the frequency response transfer function formula at the power supply node.

[0032] The calculation module is further configured to calculate the inertia coefficient and the primary frequency modulation capability coefficient of each power supply node according to each amplitude response curve.

[0033] In the third aspect, the embodiments of the present disclosure provide an electronic device, which comprises at least one processor and a memory connected with the at least one processor, and the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor to enable the at least one processor to perform the method described above.

[0034] In the fourth aspect, the embodiments of the present disclosure provide a non-transitory computer readable storage medium storing computer instructions, and the computer instructions are used to enable a computer to perform the method described above.

[0035] In the present disclosure, a small disturbance power can be injected into a power system, and the impedance at each power supply node in the power system can be calculated at this time. According to the relationship between the impedance at the power supply node and the frequency response transfer function at the power supply node, an amplitude response curve corresponding to the frequency response transfer function can be drawn, and the inertia coefficient and the primary frequency modulation capability coefficient of each power supply node can be calculated according to each amplitude response curve.

[0036] In this way, the inertia coefficient and the primary frequency modulation capability coefficient of each power supply node can be calculated in real time from the perspective of impedance under the premise of ensuring normal operation of the power system, and the inertia and the primary frequency modulation capability of the power supply node can be quickly and accurately evaluated.

[0037] It should be understood that the content described in the summary section is not intended to limit or important features of the embodiments of the present disclosure, nor to limit the scope of the present disclosure. Other features of the present disclosure will become apparent from the following description. BRIEF DESCRIPTION OF DRAWINGS

[0038] The above and other features, advantages, and aspects of embodiments of the present disclosure will become more apparent by describing in detail the embodiments thereof with reference to the attached drawings. The attached drawings are intended to better understand the present disclosure and do not limit the present disclosure. In the drawings, the same or similar elements are denoted by the same or similar reference numerals, and:

[0039] Figure 1 A flowchart of a method for evaluating the inertia and the primary frequency modulation capability of a power supply node is shown;

[0040] Figure 2 A relationship diagram of coupling impedance and frequency response transfer function is shown;

[0041] Figure 3 A magnitude response curve diagram is shown;

[0042] Figure 4 A structural diagram of an apparatus for evaluating the inertia and the primary frequency modulation capability of a power supply node is shown;

[0043] Figure 5 A structural diagram of an exemplary electronic device capable of implementing embodiments of the present disclosure is shown. DETAILED DESCRIPTION

[0044] To make the purposes, technical solutions, and advantages of the embodiments of the present disclosure clearer, the technical solutions in the embodiments of the present disclosure will be described clearly and completely below with reference to the drawings in the embodiments of the present disclosure. Obviously, the described embodiments are only part of the embodiments of the present disclosure, rather than all the embodiments of the present disclosure. Based on the embodiments in the present disclosure, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the scope of protection of the present disclosure.

[0045] In addition, the term "and / or" in this document merely describes an association relationship of associated objects, and indicates that three relationships can exist, for example, A and / or B can represent three cases of existence of A alone, existence of A and B together, and existence of B alone. In addition, the character " / " in this document generally represents an "or" relationship between the front and rear associated objects.

[0046] To solve the problems in the background art, the embodiments of the present disclosure provide a method, device and equipment for evaluating the inertia and primary frequency modulation capability of a power supply node. Specifically, a small disturbance power can be injected into a power system, and the impedance at each power supply node in the power system can be calculated at this time. According to the relationship between the impedance at the power supply node and the frequency response transfer function at the power supply node, an amplitude response curve corresponding to the frequency response transfer function is drawn, and the inertia coefficient and the primary frequency modulation capability coefficient of each power supply node are calculated according to each amplitude response curve.

[0047] In this way, the inertia coefficient and the primary frequency modulation capability coefficient of each power supply node can be calculated in real time from the perspective of impedance under the premise of ensuring the normal operation of the power system, and the inertia and the primary frequency modulation capability of the power supply node can be quickly and accurately evaluated.

[0048] The method, device and equipment for evaluating the inertia and primary frequency modulation capability of a power supply node provided by the embodiments of the present disclosure will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0049] Figure 1 A flowchart of a method for evaluating the inertia and primary frequency modulation capability of a power supply node provided by the embodiments of the present disclosure is shown in FIG. 1. Figure 1 As shown in FIG. 1, the method 100 for evaluating the inertia and primary frequency modulation capability can include the following steps:

[0050] S110, a small disturbance power is injected into a power system, and the impedance at each power supply node in the power system is calculated.

[0051] The power system is a unified whole composed of power generation, power supply (power transmission, power transformation, power distribution), power utilization facilities, and secondary facilities required for ensuring the normal operation thereof, such as regulation and control, relay protection and safety automation devices, metering devices, dispatching automation, and power communication. In the present embodiment, the power supply nodes in the power system are mostly RGUs.

[0052] In some embodiments, a small disturbance power (for example, a sinusoidal active power with strong adjustability) can be injected into the power system by using a certain power supply node in the power system, and then the impedance at each power supply node in the power system can be quickly calculated by using an impedance formula under the condition that the power system is injected with the small disturbance power.

[0053] S120, draw the amplitude response curve corresponding to the frequency response transfer function according to the impedance at the power supply node and the frequency response transfer function formula at the power supply node.

[0054] In some embodiments, the coupling impedance at the power supply node can be calculated according to the impedance at the power supply node, for example, the coupling impedance at the power supply node is calculated according to the coupling impedance formula, and then the amplitude response curve corresponding to the frequency response transfer function is quickly and accurately drawn according to the coupling impedance at the power supply node and the frequency response transfer function formula at the power supply node, that is, the amplitude response curve corresponding to each power supply node.

[0055] The frequency response transfer function formula at the power supply node can be as follows:

[0056]

[0057] Where FR(s) represents the frequency response transfer function at the power supply node n, represents the coupling impedance at the power supply node n, u sd0 represents the real-time voltage at the power supply node n, V s represents the reference voltage at the power supply node n, f represents the real-time frequency at the power supply node n, f B_PLL represents the phase-locked loop bandwidth. In this way, the coupling impedance can be used to represent the frequency response transfer function, and the amplitude response curve corresponding to the frequency response transfer function can be quickly drawn using impedance.

[0058] Exemplarily, the frequency response transfer function formula at the power supply node can be derived from the relationship diagram shown by Figure 2 , and specifically as follows:

[0059] Based on the resonance point at the perturbation injection node, the equivalent capacitance caused by inertia and the transmission line equivalent inductance occur in series resonance, and the short-term frequency dynamic response process under small power perturbation can be divided into two parts: inertia response and primary frequency response. The inertia response is immediately available, which will affect the rate of change of frequency (Rate-of-Change of, RoCoF) and the lowest point of frequency. Generally, the primary frequency response occurs after several seconds of perturbation. For a given power disturbance, the primary frequency modulation capability mainly depends on the quasi-steady frequency deviation Δfss, and the direct current gain of the amplitude response curve of the frequency response transfer function FR(s) can be used to represent the primary frequency modulation capability of the power supply node.

[0060] The impedance Z n The transformer realizes the relationship between the injected sinusoidal active power and the frequency corresponding to the power supply node n in the dq (rotating) coordinate system, and transmits the time-varying three-phase variable to the dq coordinate system through transformation. Therefore, the current and voltage of the power supply node n are related as follows:

[0061]

[0062] wherein u sd (s) is the d-axis voltage, u sq (s) is the q-axis voltage, Z sd (s) is the d-axis current, i sq (s) is the q-axis current.

[0063] Figure 2 wherein kp c and ki c represent the proportional gain and integral gain of the inner current control respectively; SSAPP represents the grid tracking converter; Z pll (s) represents the phase-locked loop (PLL) transfer function.

[0064] It can be known that the d-axis current i sd (s) is proportional to the output active power p sr (s), and the q-axis voltage u sq (s) is also proportional to the angle of u sabc (s). It is worth noting that the phase-locked loop (PLL) design also has a significant impact on the frequency response transfer function FR(s). When the phase-locked loop (f B_PLL ) bandwidth is less than 20Hz, the closed-loop transfer function is approximately T pll (s) = 1. Considering the current bandwidth control loop, f B_C is much larger than f B_PLL , the closed-loop transfer function of the current control can also be approximated as GC(s) = 1, and then the frequency response transfer function FR(s) can be represented as:

[0065]

[0066] wherein f also means f n (s) represents the real-time frequency at the power supply node n, p sr (s) represents the output active power, f B_PLL represents the phase-locked loop bandwidth, represents the coupling impedance at the power supply node n, u sd0 represents the real-time voltage at the power supply node n, V s represents the reference voltage at the power supply node n.

[0067] S130, according to the amplitude response curves, the inertia coefficient and the primary frequency modulation capability coefficient of each power supply node are calculated.

[0068] In some embodiments, the resonant frequency and the DC gain can be extracted from the amplitude response curve, the inertia coefficient of the corresponding power supply node can be quickly and accurately calculated according to the extracted resonant frequency, and the primary frequency modulation capability coefficient of the corresponding power supply node can be quickly and accurately calculated according to the extracted DC gain.

[0069] For example, the inertia coefficient of the power supply node can be calculated according to the extracted resonant frequency and the inertia coefficient formula, and exemplarily, the inertia coefficient formula can be:

[0070]

[0071] wherein H n represents the inertia coefficient of the power supply node n, ω H represents the resonant frequency extracted from the amplitude response curve corresponding to the power supply node n, L eq is the equivalent inductance of the power grid transmission line.

[0072] Meanwhile, the primary frequency modulation capability coefficient of the power supply node can be calculated according to the extracted DC gain and the primary frequency modulation capability coefficient formula, and exemplarily, the primary frequency modulation capability coefficient (MW / Hz) formula can be:

[0073]

[0074] wherein K n represents the primary frequency modulation capability coefficient of the power supply node n, R n represents the resistance at the power supply node n, f0represents the reference frequency at the power supply node n, S n represents the nominal power capacity of the generator corresponding to the power supply node n, represents the DC gain extracted from the amplitude response curve corresponding to the power supply node n.

[0075] As an example, the amplitude response curve can be as shown in Figure 3 , wherein Resonance point is the resonance point, i.e., the resonant frequency to be extracted, DC gain is the DC gain to be extracted, so that the resonant frequency ω H and the DC gain can be extracted from the amplitude response curve. H Further, the primary frequency modulation capability coefficient of the power supply node can be calculated according to the resonant frequency ω H and the DC gain .

[0076] S140, according to the inertia coefficient and the primary frequency modulation capability coefficient of each power supply node, determining the power supply node with the lowest inertia and / or primary frequency modulation capability in the power system.

[0077] That is, according to the inertia coefficient and the primary frequency modulation capability coefficient of each power supply node, the power supply node with the lowest inertia coefficient and / or primary frequency modulation capability coefficient is determined.

[0078] The embodiments of the present disclosure can consider the challenge of unbalanced events under large disturbances and the lack of consideration of virtual inertia resources, and can calculate the inertia coefficient and the primary frequency modulation capability coefficient of each power supply node in real time from the perspective of impedance under the premise of ensuring the normal operation of the power system, and then quickly and accurately evaluate the inertia and the primary frequency modulation capability of each power supply node (such as synchronous and non-synchronous power supply nodes), so as to facilitate finding the weakest power supply node or area in inertia and / or primary frequency modulation capability in the power system, and provide a basic direction for formulating appropriate control strategies to improve the frequency stability of the low-inertia power system.

[0079] Specifically, from the perspective of impedance, an approximate relationship between impedance and the corresponding frequency response transfer function FR(s) is derived based on small disturbance injection and power domain impedance method, and an implementation framework for real-time estimation of the inertia and the primary frequency modulation capability of the power supply node based on impedance is established based on this, thereby avoiding the interruption of the normal operation of the power system, and enabling the inertia and the primary frequency modulation capability of each power supply node to be quickly and accurately evaluated in the actual power system, and providing a new idea of non-invasive online evaluation for the power grid operator to evaluate the inertia and the primary frequency modulation capability of each power supply node through impedance calculation.

[0080] It should be noted that, for the foregoing method embodiments, in order to simply describe, they are all expressed as a series of action combinations, but those skilled in the art should know that the present disclosure is not limited by the order of the described actions, because according to the present disclosure, certain steps can be performed in other orders or simultaneously. Secondly, those skilled in the art should know that the embodiments described in the specification are all optional embodiments, and the actions and modules involved are not necessarily required by the present disclosure.

[0081] The above is the introduction of the method embodiment, and the scheme described in the present disclosure will be further described through the device embodiment.

[0082] Figure 4 The structure diagram of an inertia and primary frequency modulation capability evaluation device of a power supply node according to an embodiment of the present disclosure is shown in FIG. 4. Figure 4 As shown in FIG. 4, the inertia and primary frequency modulation capability evaluation device 400 can include:

[0083] The calculation module 410 is configured to inject a small disturbance power into the power system, and calculate the impedance at each power supply node in the power system.

[0084] The drawing module 420 is configured to draw an amplitude response curve corresponding to a frequency response transfer function according to an impedance at the power supply node and a frequency response transfer function formula at the power supply node.

[0085] The calculation module 410 is further configured to calculate an inertia coefficient and a primary frequency modulation capability coefficient of each power supply node according to each amplitude response curve.

[0086] In some embodiments, the small perturbation power is a sinusoidal active power.

[0087] In some embodiments, the drawing module 420 is specifically configured to:

[0088] The coupling impedance at the power supply node is calculated according to the impedance at the power supply node.

[0089] The amplitude response curve corresponding to the frequency response transfer function is drawn according to the coupling impedance at the power supply node and the frequency response transfer function formula at the power supply node.

[0090] In some embodiments, the frequency response transfer function formula at the power supply node is:

[0091]

[0092] wherein FR(s) represents the frequency response transfer function, represents the coupling impedance at the power supply node, u sd0 represents a real-time voltage at the power supply node, V s represents a reference voltage at the power supply node, f represents a real-time frequency at the power supply node, f B_PLL represents a phase-locked loop bandwidth.

[0093] In some embodiments, the calculation module 410 is specifically configured to:

[0094] The resonance frequency and the direct current gain are extracted from the amplitude response curve.

[0095] The inertia coefficient of the power supply node is calculated according to the extracted resonance frequency.

[0096] The primary frequency modulation capability coefficient of the power supply node is calculated according to the extracted direct current gain.

[0097] In some embodiments, the calculation module 410 is specifically configured to:

[0098] The inertia coefficient of the power supply node is calculated according to the extracted resonance frequency and an inertia coefficient formula, the inertia coefficient formula being:

[0099]

[0100] wherein H n represents the inertia coefficient of the power supply node, ω HFor the extracted resonant frequency, L eq This is the equivalent inductance of the power grid transmission line.

[0101] In some embodiments, the calculation module 410 is specifically used for:

[0102] The primary frequency regulation capability coefficient of the power supply node is calculated based on the extracted DC gain and primary frequency regulation capability coefficient formula. The primary frequency regulation capability coefficient formula is as follows:

[0103]

[0104] Among them, K n R represents the primary frequency regulation capability coefficient of the power node. n f0 represents the resistance at the power node, f0 represents the reference frequency at the power node, and S represents the reference frequency at the power node. n This indicates the nominal power capacity of the generator corresponding to the power node. This indicates the extracted DC gain.

[0105] Understandable Figure 4 Each module / unit in the inertial and primary frequency modulation capability evaluation device 400 shown has the function of implementing each step in the inertial and primary frequency modulation capability evaluation method 100 provided in the embodiments of this disclosure, and can achieve its corresponding technical effect. For the sake of brevity, it will not be described in detail here.

[0106] Figure 5 A structural diagram of an electronic device that can be used to implement embodiments of the present disclosure is shown. Electronic device 500 is intended to represent various forms of digital computers, such as laptop computers, desktop computers, workstations, personal digital assistants, servers, blade servers, mainframe computers, and other suitable computers. Electronic device 500 may also represent various forms of mobile devices, such as personal digital processors, cellular phones, smartphones, wearable devices, and other similar computing devices. The components shown herein, their connections and relationships, and their functions are merely illustrative and are not intended to limit the implementation of the present disclosure described and / or claimed herein.

[0107] like Figure 5 As shown, the electronic device 500 may include a computing unit 501, which can perform various appropriate actions and processes according to a computer program stored in a read-only memory (ROM) 502 or a computer program loaded from a storage unit 508 into a random access memory (RAM) 503. The RAM 503 may also store various programs and data required for the operation of the electronic device 500. The computing unit 501, ROM 502, and RAM 503 are interconnected via a bus 504. An input / output (I / O) interface 505 is also connected to the bus 504.

[0108] A plurality of components in the electronic device 500 are connected to the I / O interface 505, including: an input unit 506, such as a keyboard, a mouse, etc.; an output unit 507, such as various types of displays, speakers, etc.; a storage unit 508, such as a magnetic disk, an optical disk, etc.; and a communication unit 509, such as a network card, a modem, a wireless communication transceiver, etc. The communication unit 509 allows the electronic device 500 to exchange information / data with other devices through a computer network, such as the Internet, and / or various telecommunication networks.

[0109] The computing unit 501 can be various general and / or special-purpose processing components with processing and computing capabilities. Some examples of the computing unit 501 include, but are not limited to, a central processing unit (CPU), a graphics processing unit (GPU), various special-purpose artificial intelligence (AI) computing chips, various computing units running machine learning model algorithms, a digital signal processor (DSP), and any appropriate processor, controller, microcontroller, etc. The computing unit 501 performs various methods and processes described above, such as the method 100. For example, in some embodiments, the method 100 can be implemented as a computer program product, including a computer program tangibly embodied in a computer-readable medium, such as the storage unit 508. In some embodiments, part or all of the computer program can be loaded and / or installed onto the device 500 via the ROM 502 and / or the communication unit 509. When the computer program is loaded onto the RAM 503 and executed by the computing unit 501, one or more steps of the method 100 described above can be performed. Alternatively, in other embodiments, the computing unit 501 can be configured to perform the method 100 by any other appropriate means, such as by means of firmware.

[0110] The various implementations described above can be implemented in digital electronic circuitry, integrated circuitry, field programmable gate arrays (FPGAs), application specific integrated circuits (ASICs), application specific standard products (ASSPs), system on chips (SoCs), complex programmable logic devices (CPLDs), computer hardware, firmware, software, and / or combinations thereof. These various implementations can include implementation in one or more computer programs that are executable and / or interpretable on a programmable system including at least one programmable processor, which can be special or general purpose, coupled to receive data and instructions from, and to transmit data and instructions to, a storage system, at least one input device, and at least one output device.

[0111] Program code for carrying out operations of the methods of the present disclosure can be written in any combination of one or more programming languages. The program code can be provided to a processor or controller of a general purpose computer, special purpose computer, or other programmable data processing apparatus to produce a machine, such that the program code, when executed by the processor or controller, produces the functions / operations specified in the flowcharts and / or block diagrams. The program code can be executed entirely on a machine, partially on a machine, partially on a machine as part of a separate software package, or entirely on a remote machine or server.

[0112] In the context of the present disclosure, a computer-readable medium can be a tangible medium that can contain or store program for use by or in connection with an instruction execution system, apparatus, or device. The computer-readable medium can be a computer-readable signal medium or a computer-readable storage medium. The computer-readable medium can include, but is not limited to, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any suitable combination of the foregoing. More specific examples of the computer-readable storage medium would include one or more lines of electrical connection, a portable computer diskette, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or Flash memory), an optical fiber, a portable compact disc read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.

[0113] It should be noted that the present disclosure also provides a non-transitory computer-readable storage medium storing computer instructions, wherein the computer instructions are used to make a computer execute the method 100, and achieve the corresponding technical effects of the method executed by the embodiments of the present disclosure. For brevity, the description is not repeated here.

[0114] In addition, the present disclosure also provides a computer program product, which includes a computer program, and the computer program, when executed by a processor, implements the method 100.

[0115] To provide for interaction with a user, the above described embodiments can be implemented on a computer having a display device, e.g., a CRT (cathode ray tube) or LCD (liquid crystal display) monitor, for displaying information to the user and a keyboard and a pointing device, e.g., a mouse or a trackball, by which the user can provide input to the computer. Other kinds of devices can be used to provide for interaction with a user as well; for example, feedback provided to the user can be any form of sensory feedback, e.g., visual feedback, auditory feedback, or tactile feedback; and input from the user can be received in any form, including acoustic, speech, or tactile input.

[0116] The embodiments described above can be implemented in a computing system that includes a back end component, e.g., as a data server, or that includes a middleware component, e.g., an application server, or that includes a front end component, e.g., a user computer having a graphical user interface or a Web browser through which a user can interact with an implementation of the systems and techniques described here, or any combination of such back end, middleware, or front end components. The components of the system can be interconnected by any form or medium of digital data communication, e.g., a communication network. Examples of communication networks include a local area network (LAN), a wide area network (WAN), and the Internet.

[0117] The computer system can include clients and servers. A client and server are generally remote from each other and typically interact through a communication network. The relationship of client and server arises by virtue of computer programs running on the respective computers and having a client-server relationship to each other. The server can be a cloud server, a server of a distributed system, or a server combined with a blockchain.

[0118] It should be understood that the various forms of flow shown in the above figures can be re-ordered, added to, or deleted from without departing from the scope of the present disclosure. For example, the steps recited in the disclosure can be executed in parallel, executed in sequence, or executed in different orders, as long as the desired results of the technology disclosed in the disclosure are achieved, and the present disclosure is not limited herein.

[0119] The specific embodiments described above are not intended to be limiting. One of skill in the art will understand that various modifications, combinations, sub-combinations, and alternatives can be made to the specific embodiments described above without departing from the scope of the disclosure. Any modifications, combinations, sub-combinations, and alternatives falling within the spirit and principles of the disclosure are intended to be included in the disclosure.

Claims

1. A method for evaluating the inertia and primary frequency modulation capability of a power node, characterized in that, The method includes: Inject a small disturbance power into the power system and calculate the impedance at each power source node in the power system; Calculate the coupling impedance at the power node based on the impedance at the power node; plot the amplitude response curve corresponding to the frequency response transfer function based on the coupling impedance at the power node and the frequency response transfer function formula at the power node. Based on the response curves of each amplitude, calculate the inertia coefficient and primary frequency regulation capability coefficient of each power supply node; The small disturbance power is sinusoidal active power; The formula for the frequency response transfer function at the power node is: Where FR(s) represents the frequency response transfer function. U represents the coupling impedance at the power node. sd0 V represents the real-time voltage at the power node. s f represents the reference voltage at the power node, and f represents the real-time frequency at the power node. B_PLL Indicates the bandwidth of the phase-locked loop; The calculation of the inertia coefficient and primary frequency regulation capability coefficient of each power supply node based on the amplitude response curves includes: Extract the resonant frequency and DC gain from the amplitude response curve; The inertia coefficient of the power node is calculated based on the extracted resonant frequency; The primary frequency modulation capability coefficient of the power node is calculated based on the extracted DC gain. The calculation of the primary frequency modulation capability coefficient of the power node based on the extracted DC gain includes: The primary frequency modulation capability coefficient of the power supply node is calculated based on the extracted formula for DC gain and primary frequency modulation capability coefficient. The formula for primary frequency modulation capability coefficient is as follows: Among them, K n R represents the primary frequency modulation capability coefficient of the power node. n f0 represents the resistance at the power node, f0 represents the reference frequency at the power node, and S represents the reference frequency at the power node. n This indicates the nominal power capacity of the generator corresponding to the power node. This indicates the extracted DC gain.

2. The method according to claim 1, characterized in that, The calculation of the inertia coefficient of the power node based on the extracted resonant frequency includes: The inertia coefficient of the power supply node is calculated based on the extracted resonant frequency and inertia coefficient formula. The inertia coefficient formula is as follows: Among them, H n ω represents the inertia coefficient of the power node. H For the extracted resonant frequency, L eq This is the equivalent inductance of the power grid transmission line.

3. A device for evaluating the inertia and primary frequency modulation capability of a power node, characterized in that, The device includes: The calculation module is used to inject small disturbance power into the power system and calculate the impedance at each power source node in the power system. The plotting module is used to calculate the coupling impedance at the power node based on the impedance at the power node; and to plot the amplitude response curve corresponding to the frequency response transfer function based on the coupling impedance at the power node and the frequency response transfer function formula at the power node. The calculation module is also used to calculate the inertia coefficient and primary frequency modulation capability coefficient of each power supply node based on the amplitude response curves. The small disturbance power is sinusoidal active power; The formula for the frequency response transfer function at the power node is: Where FR(s) represents the frequency response transfer function. U represents the coupling impedance at the power node. sd0 V represents the real-time voltage at the power node. s f represents the reference voltage at the power node, and f represents the real-time frequency at the power node. B_PLL Indicates the bandwidth of the phase-locked loop; The calculation module is specifically used for: Extract the resonant frequency and DC gain from the amplitude response curve; The inertia coefficient of the power node is calculated based on the extracted resonant frequency; The primary frequency modulation capability coefficient of the power node is calculated based on the extracted DC gain. Furthermore, the primary frequency modulation capability coefficient of the power supply node is calculated based on the extracted formula for DC gain and primary frequency modulation capability coefficient. The formula for primary frequency modulation capability coefficient is as follows: Among them, K n R represents the primary frequency modulation capability coefficient of the power node. n f0 represents the resistance at the power node, f0 represents the reference frequency at the power node, and S represents the reference frequency at the power node. n This indicates the nominal power capacity of the generator corresponding to the power node. This indicates the extracted DC gain.

4. An electronic device, comprising: At least one processor; as well as A memory communicatively connected to the at least one processor; wherein, The memory stores instructions that can be executed by the at least one processor to enable the at least one processor to perform the method of any one of claims 1-2.

5. A non-transitory computer-readable storage medium storing computer instructions, wherein, The computer instructions are used to cause the computer to perform the method according to any one of claims 1-2.

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