An Adaptive Control Method, System, Device and Medium for a Virtual Synchronous Generator

Abstract

The present application discloses a virtual synchronous generator adaptive control method, system, equipment and medium, which relates to the field of electric power technology. The method optimizes virtual inertia by introducing an inverse square root function, optimizes transient damping by introducing a first-order lead-lag link, constructs a rotor mechanical equation, and combines active power and primary frequency regulation to construct an active-frequency regulation equation to determine the power angle; determines the voltage output amplitude according to the reactive-voltage regulation equation; generates a virtual electromotive force by combining the power angle and the voltage amplitude, obtains a regulation signal through a voltage and current double closed-loop control, and then generates a drive signal through pulse width modulation to control the operation of the grid-connected converter and the filter circuit, thereby realizing the control of the virtual synchronous generator. The present application improves the dynamic response performance and transient stability, suppresses the interference of instantaneous output power pulses on the system, weakens the influence of frequency oscillation on parameter setting, enhances the controllability of the output power, and effectively makes up for the shortcomings of optimizing for both transient characteristics.

Description

Technical Field

[0001] The present application relates to the field of power technologies, and particularly to a virtual synchronous generator adaptive control method, system, device, and medium. Background Art

[0002] With the increasing energy consumption and environmental pollution, microgrids containing new energy sources such as photovoltaic and wind power have received extensive attention. The development of power electronics technology provides favorable conditions for the access of new energy power generation equipment to the power grid, but also brings difficulties and challenges.

[0003] The large-scale access of distributed energy represented by photovoltaic and wind power to the power grid has gradually increased the penetration rate of power electronic devices in the power system, resulting in the traditional power system showing characteristics of low inertia, weak damping, and weak frequency support, and the system stability and security are gradually reduced. To improve the problems of grid instability and frequency oscillation caused by a high proportion of renewable energy, some scholars draw on the operating characteristics of synchronous generators (SGs), simulate their power swing equations to introduce virtual inertia and damping links, and propose virtual synchronous generator (VSG) control technology, enabling grid-connected converters to have primary frequency regulation and primary voltage regulation capabilities, and improving the system's anti-interference ability.

[0004] The introduction of virtual inertia and damping links is an effective solution to improve the system's primary frequency regulation ability and enhance the frequency dynamic stability of the system. However, conventional virtual inertia control technology makes the system characteristics of the VSG active-frequency loop change from first-order characteristics to second-order oscillation characteristics, resulting in the grid-connected operation of the converter being easily affected by active power regulation commands and grid frequency disturbances, weakening the dynamic performance of the system's active power control loop. The introduction of the damping link can be equivalent to increasing the primary frequency regulation parameter, but a large damping parameter will cause a larger steady-state deviation in the active-frequency loop. To improve the system stability, more active power compensation needs to be introduced, but this will further damage the transient stability of the system. Summary of the Invention

[0005] The purpose of the present application is to provide a virtual synchronous generator adaptive control method, system, device, and medium, which solves the problems of frequency oscillation caused by excessive inertia compensation and steady-state deviation caused by damping characteristics in adaptive control, and improves the system's dynamic response performance and transient stability.

[0006] To achieve the above purpose, the present application provides the following solutions:

[0007] In a first aspect, the present application provides a virtual synchronous generator adaptive control method, which is applied to the main circuit topology of a virtual synchronous generator. The main circuit topology of the virtual synchronous generator includes: a grid-connected converter, a filter circuit, and a main power grid connected in sequence; the virtual synchronous generator adaptive control method includes: obtaining the voltage value and current value output by the filter circuit; calculating the active power and reactive power according to the voltage value and the current value; optimizing the virtual inertia using a non-linear activation function to obtain an optimized virtual inertia; optimizing the transient damping using a first-order lead-lag link to obtain an optimized transient damping; constructing a rotor mechanical equation according to the optimized virtual inertia and the optimized transient damping; constructing an active-power-frequency regulation equation based on the active power and primary frequency regulation, in combination with the rotor mechanical equation; constructing a reactive-power-voltage regulation equation based on the reactive power and virtual excitation regulation; determining the power angle according to the active-power-frequency regulation equation and determining the voltage output amplitude according to the reactive-power-voltage regulation equation; performing voltage-current double closed-loop control according to the power angle and the voltage output amplitude to obtain a regulation signal; generating a drive signal through pulse width modulation according to the regulation signal, and controlling the operation of the grid-connected converter and the filter circuit based on the drive signal to achieve the control of the virtual synchronous generator.

[0008] In a second aspect, the present application provides a virtual synchronous generator adaptive control system for implementing the virtual synchronous generator adaptive control method. The virtual synchronous generator adaptive control system includes: a signal acquisition module for obtaining the voltage value and current value output by the filter circuit; a power calculation module for calculating the active power and reactive power according to the voltage value and the current value; a virtual inertia optimization module for optimizing the virtual inertia by using a non-linear activation function to obtain an optimized virtual inertia; a transient damping optimization module for optimizing the transient damping by using a first-order lead-lag link to obtain an optimized transient damping; a rotor mechanical equation construction module for constructing a rotor mechanical equation according to the optimized virtual inertia and the optimized transient damping; an active power-frequency regulation equation construction module for constructing an active power-frequency regulation equation based on the active power and the primary frequency regulation in combination with the rotor mechanical equation; a reactive power-voltage regulation equation construction module for constructing a reactive power-voltage regulation equation based on the reactive power and the virtual excitation regulation; a power angle and voltage output amplitude module for determining the power angle according to the active power-frequency regulation equation and determining the voltage output amplitude according to the reactive power-voltage regulation equation; a voltage-current double closed-loop control module for performing voltage-current double closed-loop control according to the power angle and the voltage output amplitude to obtain an adjustment signal; and a drive module for generating a drive signal by pulse width modulation according to the adjustment signal and controlling the operation of the grid-connected converter and the filter circuit based on the drive signal to implement the control of the virtual synchronous generator.

[0009] In a third aspect, the present application provides a computer device including: a memory, a processor, and a computer program stored on the memory and executable on the processor, where the processor executes the computer program to implement the virtual synchronous generator adaptive control method.

[0010] In a fourth aspect, the present application provides a computer-readable storage medium having a computer program stored thereon, and when the computer program is executed by a processor, the virtual synchronous generator adaptive control method is implemented.

[0011] According to the specific embodiments provided by the present application, the present application has the following technical effects.

[0012] The present application provides a virtual synchronous generator adaptive control method. By introducing a non-linear activation function to optimize the virtual inertia, the problem of frequency oscillation caused by excessive inertia compensation in adaptive control is solved, and the dynamic response performance of the system is improved. By introducing a first-order lead-lag link to improve the transient damping, the steady-state deviation problem caused by the damping characteristic of the system is eliminated, and the transient stability of the system is improved. Moreover, the present application also suppresses the interference of the instantaneous output power pulse to the system, weakens the influence of the frequency oscillation on the parameter tuning, enhances the controllability of the system output power, and effectively makes up for the shortcoming of the VSG adaptive control technology in optimizing the transient characteristics while taking into account the transient characteristics. Description of the Drawings

[0013] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings required to be used in the embodiments. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0014] Figure 1 It is the traditional VSG main circuit topology and its simplified structure diagram provided by the embodiment of the present application.

[0015] Figure 2 It is the schematic diagram of the traditional VSG adaptive control principle provided by the embodiment of the present application.

[0016] Figure 3 It is the different virtual inertias provided by the embodiment of the present application J The closed-loop zero-pole distribution trend diagram when J The closed-loop zero-pole distribution trend diagram when J The closed-loop zero-pole distribution trend diagram when J The closed-loop zero-pole distribution trend diagram when J The closed-loop zero-pole distribution trend diagram when

[0017] Figure 4 It is the control block diagram of the main circuit topology provided by the embodiment of the present application.

[0018] Figure 5 It is the schematic diagram of the virtual synchronous generator adaptive control method flow provided by the embodiment of the present application.

[0019] Figure 6 It is the change trend diagram of the ISRU function and its derivative provided by the embodiment of the present application.

[0020] Figure 7 It is the Bode diagram of the steady-state and optimized transient damping characteristics provided by the embodiment of the present application.

[0021] Figure 8 A schematic structural diagram of a computer device provided by an embodiment of the present application. Detailed implementation manners

[0022] Next, the technical solutions in the embodiments of the present application will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present application without creative efforts shall fall within the protection scope of the present application.

[0023] To make the above objects, features, and advantages of the present application more obvious and understandable, the present application will be further described in detail below in conjunction with the accompanying drawings and specific implementation manners.

[0024] Currently, in terms of improving the system dynamic oscillation, related technologies have proposed methods such as the VSG control strategy based on the intermittent change of virtual inertia, the control strategy of introducing a fuzzy controller into the power swing equation, the improved adaptive VSG control technology, and the VSG control strategy of the collaborative self-adaptation of virtual inertia parameters and damping parameters. As Figure 1 shown, the above control strategies and control methods are all applied to the VSG main circuit topology. The VSG main circuit topology includes: a grid-connected converter, a filter circuit, a point of common coupling (PCC), and a main power grid connected in sequence. The distributed power source in the grid-connected converter has a DC voltage of U dc , and through nodes A, B, and C, the three-phase currents i La , i Lb and i Lc are respectively fed into the filter circuit. After filtering through the filter inductor L f and the inductance parasitic resistance R f , the point function inversion is realized, and then the electrical energy interaction with the main power grid is realized through the PCC; where L g is the main power grid line inductance, U g is the main power grid phase voltage, and through the virtual power angle ∠ δ and the virtual voltage amplitude EGenerate a virtual electromotive force, and then obtain an adjustment signal through a voltage-current double closed-loop control strategy to achieve the control of the grid-connected converter in the main circuit topology of the VSG. However, current related research is mostly based on the stable operation condition of the power grid, focusing on improving the small-signal stability of the system, without alleviating the steady-state deviation problem caused by the coupling of damping parameters and frequency modulation parameters, nor involving the optimization of transient stability under large disturbances of the system. In terms of improving transient stability, methods such as selecting flexible parameters, introducing a first-order differential compensation link, and a first-order lead-lag link are proposed, but the influence of fault duration and high-frequency interference signals on the system is ignored, and the analysis of specific parameters is lacking.

[0025] In addition, based on the dynamic output characteristics of the active power of the traditional VSG, the small-signal transfer function of the active power closed-loop of the traditional VSG can be deduced as follows.

[0026] (1).

[0027] Where, is the small-signal transfer function of the active power closed-loop of the VSG; J 0 is the virtual inertia; D 0 is the steady-state damping coefficient; ω 0 is the rated angular frequency; K q is the reactive power regulation coefficient; K ω is the primary frequency modulation coefficient; ΔP out1 is the change in output power; Δ P ref1 is the change in the active power regulation command, s is the differential operator.

[0028] Based on formula (1), the schematic diagram of the adaptive control of the traditional VSG can be derived from the small-signal transfer function of the active power closed-loop of the traditional VSG, as Figure 2 shown. Its specific working process is as follows: The active power-frequency loop of the VSG obtains the virtual power angle P m through the primary frequency regulation equation (the primary frequency regulation equation includes the primary frequency regulation power P ref the active power regulation command, K ω the primary frequency modulation coefficient, the rated angular frequency, and ω the virtual angular frequency) and the rotor mechanical equation; The voltage output amplitude δ of the reactive power-voltage loop includes the no-load electromotive force E of the virtual synchronous generator, the reactive power regulation deviation E 0, ΔE Qand the voltage regulation deviation of the virtual synchronous generator output terminal ΔE U , specifically by combining the virtual excitation regulation equation (the virtual excitation regulation equation includes the voltage regulation coefficient K u , the voltage regulation command of the virtual synchronous generator output terminal U ref and the instantaneous voltage value of the virtual synchronous generator output terminal U ) and the reactive power regulation equation (the reactive power regulation equation includes the reactive power regulation coefficient K q , the reactive power regulation command Q ref and the reactive power output power of the virtual synchronous generator Q out ) and the no-load electromotive force E 0 to obtain the virtual voltage amplitude E 1, combined with the virtual power angle δ 1 and the virtual voltage amplitude E 1 to generate a virtual electromotive force, and a pulse width modulation (Pulse Width Modulation, PWM) regulation signal is obtained through a voltage-current double closed-loop control strategy to realize the control of the grid-connected converter in the VSG main circuit topology.

[0029] According to the closed-loop small-signal transfer function of the VSG active power closed-loop, the distribution trend of the closed-loop zero and poles of the system under different virtual inertia values is plotted as shown in Figure 3 . Among them, Figure 3 in (a) represents the distribution trend of the closed-loop zero and poles when the virtual inertia J 0 is 2; Figure 3 in (b) represents the distribution trend of the closed-loop zero and poles when the virtual inertia J 0 is 4; Figure 3 in (c) represents the distribution trend of the closed-loop zero and poles when the virtual inertia J 0 is 6; Figure 3 in (d) represents the distribution trend of the closed-loop zero and poles when the virtual inertia J 0 is 10; among them, the arrow direction is the distribution trend of the system closed-loop poles when D 0 gradually increases from 0 to 2 K. Referring to Figure 3 , it can be seen that there is a pair of conjugate poles in the active power closed-loop system. When the steady-state damping coefficient D 0 is in the same changing trend, with the gradual increase of the virtual inertia J 0 value, the starting positions of the conjugate poles s 1 and s 2 are closer to the imaginary axis, resulting in a decrease in the damping ratio of the system and weakening the stability and regulation rate of the VSG. When the virtual inertia J 0 remains unchanged, asD With the gradual increase of 0, the conjugate poles s 1 and s 2 gradually change according to the trend shown by the arrow and gradually transition into two real poles. The characteristics of the active small-signal system gradually change from under-damped characteristics to over-damped characteristics, resulting in a decrease in the response rate and steady-state control accuracy of the system.

[0030] According to the above analysis, it can be seen that when the traditional VSG control is in grid-connected operation, the steady-state characteristics of its active power are determined by D 0 and have nothing to do with J 0. The active dynamic characteristics are related to the selection of both D 0 and J 0. To meet the system's requirements for dynamic damping and low overshoot, a relatively large D 0 is selected, which easily leads to a large steady-state deviation and reduces the system response rate; to meet the system's requirement for regulation rate, a relatively large J 0 is selected, which easily causes the system damping ratio to decrease, resulting in an increase in overshoot during the dynamic response process and reducing the system stability. Therefore, D the selection of the J 0 and

[0031] parameters makes the dynamic and steady-state characteristics of the system influence each other and there is a contradiction, so a compromise selection is needed. Figure 4 In an exemplary embodiment of the present application, a virtual synchronous generator adaptive control method is provided. The virtual synchronous generator adaptive control method is applied to the Figure 5 VSG main circuit topology shown in. The virtual synchronous generator adaptive control method, as shown in

[0032] Step 100, obtain the voltage value and current value output by the filter circuit.

[0033] Step 101, calculate the active power and reactive power according to the voltage value and current value.

[0034] Step 102, optimize the virtual inertia using a non-linear activation function to obtain the optimized virtual inertia.

[0035] Step 103, optimize the transient damping using a first-order lead-lag link to obtain the optimized transient damping.

[0036] Step 104, construct a rotor mechanical equation according to the optimized virtual inertia and the optimized transient damping.

[0037] Step 105, based on the active power and primary frequency regulation, combine with the rotor mechanical equation to construct an active-frequency regulation equation.

[0038] Step 106: Based on the reactive power and virtual excitation regulation, construct a reactive power-voltage regulation equation.

[0039] Step 107: Determine the power angle according to the active power-frequency regulation equation, and determine the voltage output amplitude according to the reactive power-voltage regulation equation.

[0040] Step 108: Perform double closed-loop control of voltage and current according to the power angle and voltage output amplitude to obtain a regulation signal.

[0041] Step 109: According to the regulation signal, generate a drive signal through pulse width modulation, and based on the drive signal, control the operation of the grid-connected converter and the filter circuit to achieve the control of the virtual synchronous generator.

[0042] By implementing the above steps, in this application, the virtual inertia is optimized by introducing a non-linear activation function, the transient damping is optimized by introducing a first-order lead-lag link, a rotor mechanical equation is constructed, and combined with the active power and primary frequency regulation, an active power-frequency regulation equation is constructed, and then the power angle is determined; the double closed-loop control of voltage and current is performed according to the power angle and the voltage output amplitude determined by the reactive power-voltage regulation equation to obtain a regulation signal, and then a drive signal is generated through pulse width modulation to control the operation of the grid-connected converter and the filter circuit to achieve the control of the virtual synchronous generator.

[0043] In an exemplary embodiment of this application, the active power P out and reactive power Q out are expressed as follows.

[0044] (2).

[0045] Where P out is the active output power of the VSG; Q out is the reactive output power of the VSG; X is the line equivalent impedance; E 1 is the voltage amplitude command output by the VSG; U g is the phase voltage of the main power grid; δ 1 is the phase angle difference between the VSG and the main power grid voltage.

[0046] In an exemplary embodiment of this application, the non-linear activation function is the inverse square root function (ISDN Remote Subscriber Unit, IRSU function), and the expression of the optimized virtual inertia is as follows.

[0047] (3).

[0048] Among them, J ω is the optimized virtual inertia; J 0 is the steady-state value of the virtual inertia; K j is the adaptive compensation coefficient; ω is the virtual angular frequency; t represents time; ω ref is the given angular frequency; T j is the adaptive virtual inertia determination threshold; is the virtual inertia compensation amount based on the inverse square root function.

[0049] The general expression of the inverse square root function is as follows.

[0050] (4).

[0051] Among them, is the inverse square root function, a is the adjustment coefficient of the inverse square root function; x is the independent variable of the inverse square root function.

[0052] Compared with the traditional virtual synchronous generator adaptive control method, the virtual synchronous generator adaptive control method proposed in this application introduces the ISRU function to optimize the virtual inertia in terms of improving the VSG inertia characteristics, and further optimizes the transient stability of the VSG adaptive control. According to Figure 6 It can be seen that in the linear function ( y = x ), the ISRU function ( y = ISRU( x )) and y = ISRU(2 x ))), as well as the ISRU differential function ( y = d (ISRU( x )) / dt ), when the adjustment coefficient of the ISRU function is equal to 2, that is, y = ISRU(2 x ), the virtual inertia compensation value introducing the ISRU function characteristics can suppress the angular frequency deviation in a shorter time and accelerate the angular frequency recovery rate. By adopting the ISRU function to optimize the virtual inertia, the problem of frequency oscillation caused by excessive inertia compensation in VSG adaptive control is solved, and the dynamic response performance is improved.

[0053] In an exemplary embodiment of this application, the expression of the optimized transient damping is provided as follows.

[0054] (5).

[0055] Wherein, D ω is the optimized transient damping; G D ( s ) is the first-order lead-lag link; D 0 is the steady-state damping coefficient; is the rated angular frequency; T d is the transient damping decay time constant; s is the differential operator.

[0056] And, the compensation power of the optimized transient damping is as follows.

[0057] (6).

[0058] Wherein, P D is the compensation power of the optimized transient damping; ω is the virtual angular frequency.

[0059] Compared with the traditional virtual synchronous generator adaptive control method, the virtual synchronous generator adaptive control method proposed in this application introduces a first-order lead-lag link G D ( s ) in improving the VSG damping characteristics, while enhancing the transient stability performance and interference suppression performance of the system, weakening the steady-state error of the system. According to Figure 7 shown in the Bode diagram of the first-order lead-lag link, the optimized transient damping D ω shows an attenuation characteristic in the gain of the phase in the low-frequency band, that is, when the system is operating stably , to resolve the influence of the steady-state damping D 0 on the system control performance. In the high-frequency band, the amplitude of the optimized transient damping D ω approaches 0 dB, which can effectively suppress the high-frequency interference signals of the system and enhance the transient stability of the system. By adopting a first-order lead-lag link to optimize the transient damping, this application eliminates the steady-state deviation problem caused by the damping characteristics in the VSG adaptive control and enhances the transient stability.

[0060] In an exemplary embodiment of this application, the rotor mechanical equation is provided as follows.

[0061] (7).

[0062] Wherein, P outis the active output power of the virtual synchronous generator; P ref is the active power regulation command; J ω is the optimized virtual inertia; is the rated angular frequency; ω is the virtual angular frequency; D ω is the optimized transient damping; t is the time.

[0063] In an exemplary embodiment of the present application, the expression for primary frequency regulation is as follows.

[0064] (8).

[0065] Wherein, P m is the primary frequency regulation power; P ref is the active power regulation command; K ω is the primary frequency modulation coefficient; is the rated angular frequency; ω is the virtual angular frequency.

[0066] The active - frequency regulation equation is as follows.

[0067] (9).

[0068] Wherein, P out is the active output power of the VSG; P ref is the active power regulation command; K ω is the primary frequency modulation coefficient; is the rated angular frequency; ω is the virtual angular frequency; J ω is the virtual moment of inertia; D 0 is the steady - state damping coefficient, t is the time.

[0069] In an exemplary embodiment of the present application, the reactive - voltage regulation equation is as follows.

[0070] (10).

[0071] Wherein, E is the voltage output amplitude; E 0 is the no - load electromotive force of the virtual synchronous generator; ΔE Q is the reactive power regulation deviation;ΔE U is the voltage regulation deviation at the output terminal of the virtual synchronous generator; K q is the reactive power regulation coefficient; Q ref is the reactive power regulation command; Q out is the reactive power output of the virtual synchronous generator; K u is the voltage regulation coefficient; U ref is the voltage regulation command at the output terminal of the virtual synchronous generator; U is the instantaneous voltage value at the output terminal of the virtual synchronous generator.

[0072] In an exemplary embodiment of the present application, when the virtual synchronous generator adaptive control method operates in the grid-connected mode, an optimized virtual inertia and transient damping link are introduced G D ( s ) the active power output of the VSG P out The closed-loop transfer function is as follows.

[0073] (11).

[0074] (12).

[0075] Wherein, J ω is the virtual moment of inertia; ω 0 is the rated angular frequency; T d is the transient damping decay time constant; D 0 is the steady-state damping coefficient; K ω is the primary frequency regulation coefficient; K q is the reactive power regulation coefficient; P ref is the active power regulation command; ω is the virtual angular frequency; G D ( s ) is a first-order lead-lag link; s is the differential operator; is the closed-loop transfer function of the improved VSG control under active power disturbance; is the closed-loop transfer function of the improved VSG control under grid frequency drop; a, b 、 c 、 d 、 a 1 、b 1 , a 2 , b 2 and c 2 are the coefficients of the response and have no specific meaning.

[0076] From Equation (11) and Equation (12), the steady-state active power P output by the optimized VSG with transient damping characteristics during grid-connected operation can be derived as follows. outs-G As follows.

[0077] (13).

[0078] According to Equation (11) and Equation (12), the optimized VSG adaptive control principle can be obtained. As shown, this method optimizes the virtual inertia by introducing the ISRU function, optimizes the transient damping by introducing a first-order lead-lag link, constructs an optimized rotor mechanical equation, combines the active power and primary frequency regulation, constructs an optimized active-frequency regulation equation, and then determines the power angle; determines the voltage output amplitude according to the reactive-voltage regulation equation; generates a virtual electromotive force by combining the power angle and voltage amplitude, obtains a regulation signal through voltage-current double closed-loop control, and then generates a drive signal through pulse width modulation to control the operation of the grid-connected converter and the filter circuit, realizing the control of the virtual synchronous generator. Figure 4 As shown, this method optimizes the virtual inertia by introducing the ISRU function, optimizes the transient damping by introducing a first-order lead-lag link, constructs an optimized rotor mechanical equation, combines the active power and primary frequency regulation, constructs an optimized active-frequency regulation equation, and then determines the power angle; determines the voltage output amplitude according to the reactive-voltage regulation equation; generates a virtual electromotive force by combining the power angle and voltage amplitude, obtains a regulation signal through voltage-current double closed-loop control, and then generates a drive signal through pulse width modulation to control the operation of the grid-connected converter and the filter circuit, realizing the control of the virtual synchronous generator.

[0079] In an exemplary embodiment, a virtual synchronous generator adaptive control system is provided. The virtual synchronous generator adaptive control system is used to implement the virtual synchronous generator adaptive control method; the virtual synchronous generator adaptive control system includes the following structure.

[0080] A signal acquisition module, which is used to obtain the voltage value and current value output by the filter circuit.

[0081] A power calculation module, which is used to calculate the active power and reactive power according to the voltage value and current value.

[0082] A virtual inertia optimization module, which is used to optimize the virtual inertia by using a non-linear activation function to obtain the optimized virtual inertia.

[0083] A transient damping optimization module, which is used to optimize the transient damping by using a first-order lead-lag link to obtain the optimized transient damping.

[0084] A rotor mechanical equation construction module, which is used to construct a rotor mechanical equation according to the optimized virtual inertia and the optimized transient damping.

[0085] The active-power - frequency regulation equation construction module is used to construct an active-power - frequency regulation equation based on the active power and the primary frequency regulation, in combination with the rotor mechanical equation.

[0086] The reactive-power - voltage regulation equation construction module is used to construct a reactive-power - voltage regulation equation based on the reactive power and the virtual excitation regulation.

[0087] The power angle and voltage output amplitude module is used to determine the power angle according to the active-power - frequency regulation equation and determine the voltage output amplitude according to the reactive-power - voltage regulation equation.

[0088] The voltage and current double closed-loop control module is used to perform voltage and current double closed-loop control according to the power angle and the voltage output amplitude to obtain an adjustment signal.

[0089] The drive module is used to generate a drive signal through pulse width modulation according to the adjustment signal, and based on the drive signal, control the operation of the grid-connected converter and the filter circuit to achieve the control of the virtual synchronous generator.

[0090] In an exemplary embodiment of the present application, a computer device is provided, including: a memory, a processor, and a computer program stored on the memory and executable on the processor, and the processor executes the computer program to implement the virtual synchronous generator adaptive control method.

[0091] In an exemplary embodiment of the present application, a computer device is provided. The computer device can be a server or a terminal, and its internal structure diagram can be as Figure 8 shown. The computer device includes a processor, a memory, an input / output interface (Input / Output, abbreviated as I / O), and a communication interface. Among them, the processor, the memory, and the input / output interface are connected through a system bus, and the communication interface is connected to the system bus through the input / output interface. Among them, the processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system, a computer program, and a database. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The database of the computer device is used to store virtual synchronous generator adaptive control data. The input / output interface of the computer device is used to exchange information between the processor and external devices. The communication interface of the computer device is used to communicate with external terminals through a network connection. When the computer program is executed by the processor, it implements a virtual synchronous generator adaptive control method.

[0092] Those skilled in the art can understand, Figure 8The structure shown is only a block diagram of some structures related to the solution of this application, and does not constitute a limitation on the computer device to which the solution of this application is applied. The specific computer device may include more or fewer components than those shown in the figure, or combine some components, or have different component arrangements. In an exemplary embodiment, a computer device is provided, including a memory and a processor. A computer program is stored in the memory, and when the processor executes the computer program, the steps in the above method embodiments are implemented.

[0093] In an exemplary embodiment, a computer-readable storage medium is provided, storing a computer program, and when the computer program is executed by a processor, the steps in the above method embodiments are implemented.

[0094] It should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data for analysis, stored data, displayed data, etc.) involved in this application are all information and data authorized by the user or fully authorized by all parties, and the collection, use, and processing of relevant data need to comply with relevant regulations.

[0095] Those of ordinary skill in the art can understand that all or part of the processes of implementing the methods in the above embodiments can be completed by instructing relevant hardware through a computer program. The computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the above method embodiments. Among them, any reference to a memory, database, or other medium used in the embodiments provided in this application can include at least one of non-volatile and volatile memories. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetoresistive random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. By way of illustration and not limitation, RAM can be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM), etc.

[0096] In each of the embodiments provided in the present application, the database involved may include at least one of a relational database and a non-relational database. The non-relational database may include a distributed database based on a blockchain, etc., without limitation. The processor involved in each of the embodiments provided in the present application may be a general-purpose processor, a central processing unit, a graphics processing unit, a digital signal processor, a programmable logic device, a data processing logic device based on quantum computing, etc., without limitation.

[0097] The technical features of the above embodiments can be combined arbitrarily. For the sake of brevity of description, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered to be within the scope described in this specification.

[0098] Specific examples are used herein to elaborate on the principles and implementation manners of the present application. The description of the above embodiments is only used to help understand the method and its core idea of the present application; at the same time, for those of ordinary skill in the art, according to the idea of the present application, there will be changes in the specific implementation manners and application scopes. In summary, the content of this specification should not be construed as a limitation to the present application.

Claims

1. An adaptive control method for a virtual synchronous generator, characterized in that, The virtual synchronous generator adaptive control method is applied to the main circuit topology of a virtual synchronous generator. The main circuit topology of the virtual synchronous generator includes: a grid-connected converter, a filter circuit, and a main power grid connected in sequence. The virtual synchronous generator adaptive control method includes: Obtain the voltage value and current value output by the filter circuit; Calculate the active power and reactive power according to the voltage value and the current value; Optimize the virtual inertia using a non-linear activation function to obtain the optimized virtual inertia; the non-linear activation function is the inverse square root function; the expression of the optimized virtual inertia is: ； Among them, J ω is the optimized virtual inertia; J 0 is the steady-state value of the virtual inertia; K j is the adaptive compensation coefficient; ω is the virtual angular frequency; t represents time; ω ref is the given angular frequency; T j is the determination threshold of the adaptive virtual inertia; is the virtual inertia compensation amount based on the inverse square root function; Optimize the transient damping using a first-order lead-lag link to obtain the optimized transient damping; Construct a rotor mechanical equation according to the optimized virtual inertia and the optimized transient damping; Based on the active power and primary frequency regulation, combine with the rotor mechanical equation to construct an active-frequency regulation equation; Based on the reactive power and virtual excitation regulation, construct a reactive-voltage regulation equation; Determine the power angle according to the active-frequency regulation equation and determine the voltage output amplitude according to the reactive-voltage regulation equation; Perform voltage-current double closed-loop control according to the power angle and the voltage output amplitude to obtain a regulation signal; According to the regulation signal, generate a drive signal through pulse width modulation, and based on the drive signal, control the operation of the grid-connected converter and the filter circuit to achieve the control of the virtual synchronous generator.

2. The adaptive control method of the virtual synchronous generator according to claim 1, characterized in that The expression of the optimized transient damping is: ； Among them, D ω is the optimized transient damping; G D ( s ) is a first-order lead-lag link; D 0 is the steady-state damping coefficient; is the rated angular frequency; T d is the transient damping decay time constant; s is the differential operator.

3. The adaptive control method of the virtual synchronous generator according to claim 1, characterized in that The rotor mechanical equation is: ； Among them, P out is the active output power of the virtual synchronous generator; P ref is the active power regulation command; J ω is the optimized virtual inertia; is the rated angular frequency; ω is the virtual angular frequency; D ω is the optimized transient damping; t is the time.

4. The adaptive control method of the virtual synchronous generator according to claim 1, characterized in that, The expression of the primary frequency regulation is: ； Among them, P m is the primary frequency regulation power; P ref is the active power regulation command; K ω is the primary frequency modulation coefficient; is the rated angular frequency; ω is the virtual angular frequency.

5. The adaptive control method of the virtual synchronous generator according to claim 1, wherein The active-frequency regulation equation is: ； Among them, P out is the active output power of the virtual synchronous generator; P ref is the active power regulation command; K ω is the primary frequency regulation coefficient; is the rated angular frequency; ω is the virtual angular frequency; J ω is the optimized virtual inertia; D ω is the optimized transient damping; t is time; s is the differential operator.

6. The adaptive control method of the virtual synchronous generator according to claim 1, characterized in that The reactive-voltage regulation equation is: ； Among them, E is the amplitude of the voltage output; E 0 is the no-load electromotive force of the virtual synchronous generator; ΔE Q is the reactive power regulation deviation; Δ E U is the voltage regulation deviation at the output end of the virtual synchronous generator; K q is the reactive power regulation coefficient; Q ref is the reactive power regulation command; Q out is the reactive power output of the virtual synchronous generator; K u is the voltage regulation coefficient; U ref is the voltage regulation command at the output end of the virtual synchronous generator; U is the instantaneous voltage value at the output end of the virtual synchronous generator.

7. A virtual synchronous generator adaptive control system, characterized in that The virtual synchronous generator adaptive control system is used to implement the virtual synchronous generator adaptive control method described in any one of claims 1-6; The virtual synchronous generator adaptive control system includes: A signal acquisition module for obtaining the voltage value and current value output by the filter circuit; A power calculation module for calculating the active power and reactive power according to the voltage value and the current value; A virtual inertia optimization module for optimizing the virtual inertia using a non-linear activation function to obtain the optimized virtual inertia; the non-linear activation function is the inverse square root function; the expression of the optimized virtual inertia is: ； Among them, J ω is the optimized virtual inertia; J 0 is the steady-state value of the virtual inertia; K j is the adaptive compensation coefficient; ω is the virtual angular frequency; t represents time; ω ref is the given angular frequency; T j is the adaptive virtual inertia determination threshold; is the virtual inertia compensation amount based on the inverse square root function; A transient damping optimization module for optimizing the transient damping using a first-order lead-lag link to obtain the optimized transient damping; A rotor mechanical equation construction module for constructing a rotor mechanical equation according to the optimized virtual inertia and the optimized transient damping; An active-frequency regulation equation construction module for constructing an active-frequency regulation equation by combining the active power and the primary frequency regulation with the rotor mechanical equation; A reactive-voltage regulation equation construction module for constructing a reactive-voltage regulation equation based on the reactive power and virtual excitation regulation; A power angle and voltage output amplitude module for determining the power angle according to the active-frequency regulation equation and determining the voltage output amplitude according to the reactive-voltage regulation equation; A voltage-current double closed-loop control module is used to perform voltage-current double closed-loop control according to the power angle and the output amplitude of the voltage to obtain an adjustment signal; A driving module is used to generate a driving signal through pulse width modulation according to the adjustment signal, and based on the driving signal, control the operation of the grid-connected inverter and the filtering circuit to realize the control of the virtual synchronous generator.

8. A computer device, comprising: A memory, a processor, and a computer program stored on the memory and executable on the processor, wherein the processor executes the computer program to implement the virtual synchronous generator adaptive control method according to any one of claims 1-6.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the virtual synchronous generator adaptive control method according to any one of claims 1-6.

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