Mesh construction type energy storage power control method and system based on feedforward virtual damping adjustment

Abstract

The invention discloses a network construction type energy storage power control method and system based on feed-forward virtual damping adjustment, and the method comprises the steps: obtaining a power angle compensation amount through an angular frequency difference value and a feed-forward virtual damping coefficient outputted by a corrected adaptive adjustment model; a power angle reference value is obtained through the difference value between the output angular frequency and the power grid frequency, and the sum of the power angle reference value and the power angle compensation amount serves as an output power angle; based on the output voltage amplitude and the output power angle of the virtual synchronous generator, obtaining a reference voltage controlled by an input voltage current inner loop; the problem that dynamic stability and state response characteristics of the system cannot be considered is solved, and steady-state active power deviation cannot be increased.

Description

Technical Field

[0001] The present invention belongs to the field of grid-type energy storage power control, and in particular relates to a grid-type energy storage power control method and system based on feedforward virtual damping regulation. Background Art

[0002] Virtual synchronous generator technology (VSG) usually uses the droop control method to simulate the primary frequency regulation characteristics of synchronous generators, and introduces virtual inertia and virtual damping coefficient to suppress the power frequency oscillation of the system, which can be used to solve the stability problem of new power systems. When the traditional VSG system is in steady-state operation and there is a frequency deviation, increasing the virtual damping coefficient can effectively suppress the active power oscillation, but the steady-state output power deviation increases, and there is a contradiction between the dynamic and steady-state characteristics of the system.

[0003] In order to solve the problems caused by the virtual damping coefficient of VSG, the existing technology improves the traditional VSG model and proposes an equivalent damping ratio method, that is, the equivalent damping of the system is determined by the value of the introduced parameter, a proportional differential link is added to the inertia channel, and the damping coefficient is set to zero to eliminate the active steady-state error caused by the damping in the VSG control. The equivalent damping of the system can be affected by changing the size of the introduced proportional parameter, but the introduction of the differential link will cause high-frequency interference problems. The VSG control strategy that introduces transient electromagnetic power compensation introduces a lead-lag link in the electromagnetic power feedback channel to construct transient electromagnetic power, so that the equivalent damping coefficient only plays a role in the transient process, which can effectively solve the contradiction between the dynamic and steady states of the system. However, the method of constructing transient damping causes a large overshoot phenomenon in the transient output active power when the system is disturbed. The VSG control strategy based on the lead-lag link with additional feedforward damping uses the frequency difference to directly correct the VSG angular frequency through a lead-lag link, compensating for the phase difference generated by the control and measurement links, thereby providing positive damping for the system and resolving the contradiction between the dynamic and steady states of the system. However, the model of this method is relatively complex, which increases the difficulty of system stability analysis. At the same time, the current improved virtual damping control strategy is only designed for fixed parameters and cannot achieve ideal control effects. Summary of the invention

[0004] In order to solve the deficiencies in the prior art, the present invention provides a grid-type energy storage power control method and system based on feedforward virtual damping regulation, which overcomes the problems of damping feedback control in traditional VSG control of grid-type energy storage, and solves the problem that the dynamic stability and state response characteristics of the system cannot be taken into account due to the mutual coupling between the active power droop coefficient and the damping coefficient in traditional VSG control. At the same time, it also avoids the existing method of constructing transient damping power, which always has a large overshoot phenomenon in the output active dynamic response when the system is disturbed, and the resulting system model upgrade, complex parameter design and other problems.

[0005] The present invention adopts the following technical solution.

[0006] The present invention proposes a grid-type energy storage power control method based on feedforward virtual damping regulation, comprising:

[0007] The power angle compensation is obtained by using the angular frequency difference and the feedforward virtual damping coefficient output by the modified adaptive adjustment model;

[0008] The power angle reference value is obtained by using the difference between the output angular frequency and the grid frequency, and the sum of the power angle reference value and the power angle compensation amount is used as the output power angle;

[0009] Based on the output voltage amplitude and output power angle of the virtual synchronous generator, a reference voltage for input voltage and current inner loop control is obtained;

[0010] The modified adaptive adjustment model modifies the adaptive adjustment model of the feedforward virtual damping coefficient based on the minimum deviation of the system steady-state active power.

[0011] The power angle compensation is obtained by using the angular frequency difference and the feedforward virtual damping coefficient output by the modified adaptive adjustment model, including:

[0012] Obtain the angular frequency difference and output angular frequency;

[0013] The angular frequency difference Δω satisfies the following relationship:

[0014]

[0015] The output angular frequency ω satisfies the following relationship:

[0016] ω=Δω+ω0

[0017] Where, J is the virtual inertia coefficient; k p is the primary frequency modulation coefficient, s is the Laplace operator, P ref is the active power command, P e is the steady-state active power of the system, and ω0 is the rated angular frequency of the power grid.

[0018] The power angle compensation is obtained by using the angular frequency difference and the feedforward virtual damping coefficient output by the modified adaptive adjustment model, including:

[0019] An adaptive adjustment model of the feedforward virtual damping coefficient is established based on the change rate of the output angular frequency;

[0020] Feedforward virtual damping coefficient k d The adaptive adjustment model satisfies the following relationship:

[0021]

[0022] In the formula, k d0 is the reference value of the feedforward virtual damping coefficient, a is the feedforward virtual damping adjustment coefficient, and b is the angular frequency change rate threshold.

[0023] Characterizing that the power grid system is in a stable state, the baseline value of the feedforward virtual damping coefficient makes the equivalent damping of the virtual synchronous generator 0.707.

[0024] Power angle compensation δ d Satisfies the following relationship:

[0025] δ d =Δω·k d

[0026] Power angle reference value δ g Satisfies the following relationship:

[0027]

[0028] The output power angle δ satisfies the following relationship:

[0029] δ=δ g +δ d

[0030] In the formula, ω g is the grid frequency.

[0031] The modified adaptive adjustment model is based on the minimum system steady-state active power deviation, and modifies the adaptive adjustment model of the feedforward virtual damping coefficient, including:

[0032] Taking the minimum deviation of the steady-state active power of the system as the optimization goal, based on the first transfer function and the second transfer function of the active power control loop, the feedforward virtual damping adjustment coefficient a and the angular frequency change rate threshold b in the adaptive adjustment model of the feedforward virtual damping coefficient are iteratively solved to obtain the optimal value a of the feedforward virtual damping adjustment coefficient. * and the optimal value b of the angular frequency change rate threshold * ; Based on a * , b * , and obtain the modified adaptive adjustment model.

[0033] The first transfer function and the second transfer function of the active power control loop satisfy the following relationship:

[0034]

[0035] In the formula, G PP,VDF-VSG is the first transfer function of the active power control loop, G Pω,VDF-VSG is the second transfer function of the active power control loop, ΔP eis the system steady-state active power deviation, ΔP ref is the change in active power command, Δω g is the change of grid frequency, and K is the proportional coefficient of the transfer function.

[0036] The system steady-state active power satisfies the following relationship:

[0037]

[0038] In the formula, G PP,VDF-VSG (s) is the frequency domain expression of the first transfer function of the active power control loop, G Pω,VDF-VSG (s) is the frequency domain expression of the second transfer function of the active power control loop.

[0039] The feedforward virtual damping adjustment coefficient is 0.025, and the angular frequency change rate threshold is 0.2.

[0040] The present invention also proposes a grid-type energy storage power control system based on feedforward virtual damping regulation, comprising:

[0041] Power angle compensation calculation module, output power angle calculation module, reference voltage calculation module, model correction module, reference voltage correction module;

[0042] A power angle compensation calculation module is used to obtain a power angle compensation by using an angular frequency difference and a feedforward virtual damping coefficient output by a modified adaptive adjustment model;

[0043] An output power angle calculation module is used to obtain a power angle reference value by using the difference between the output angular frequency and the grid frequency, and to use the sum of the power angle reference value and the power angle compensation amount as the output power angle;

[0044] The reference voltage calculation module is used to obtain the reference voltage for the input voltage and current inner loop control based on the output voltage amplitude and output power angle of the virtual synchronous generator.

[0045] The power angle compensation calculation module includes: a collection unit and an adaptive adjustment model unit;

[0046] An acquisition unit, used for acquiring an angular frequency difference and outputting an angular frequency;

[0047] The adaptive adjustment model unit is used to establish an adaptive adjustment model of the feedforward virtual damping coefficient based on the change rate of the output angular frequency.

[0048] The power angle compensation amount calculation module also includes: an adaptive adjustment model correction unit;

[0049] The adaptive adjustment model correction unit is used to correct the adaptive adjustment model of the feedforward virtual damping coefficient based on the minimum deviation of the system steady-state active power.

[0050] A terminal comprises a processor and a storage medium; the storage medium is used to store instructions; the processor is used to operate according to the instructions to execute the steps of the method.

[0051] A computer-readable storage medium stores a computer program, which implements the steps of the method when executed by a processor.

[0052] The beneficial effect of the present invention is that, compared with the prior art, at least the method proposed by the present invention introduces a feedforward virtual damping coefficient, increases the damping coefficient of the feedforward damping according to the disturbance conditions to improve the dynamic response of the system, and at the same time does not cause an increase in the steady-state active power deviation.

[0053] At the same time, the feedforward virtual damping coefficient will not cause the system model to be upgraded, and the value of the feedforward virtual damping coefficient can be adaptively changed according to the rate of change of the angular frequency. The parameter design is simple to quickly suppress active power oscillation and frequency fluctuation. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] Figure 1 It is a main circuit control structure diagram of a virtual synchronous generator in an example of the present invention;

[0055] Figure 2 It is a control block diagram of the active loop of a conventional virtual synchronous generator in an example of the present invention;

[0056] Figure 3 It is a block diagram of active loop control of a virtual synchronous generator in an example of the present invention;

[0057] Figure 4 is a comparison diagram of active responses of a virtual synchronous generator using a traditional virtual synchronous generator and a virtual synchronous generator using feedforward virtual damping regulation proposed by the present invention in an example of the present invention;

[0058] Figure 5 It is a damping variation diagram of a virtual synchronous generator using the adaptive feedforward virtual damping proposed by the present invention in an example of the present invention. DETAILED DESCRIPTION

[0059] In order to make the purpose, technical scheme and advantages of the present invention clearer, the technical scheme of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. The embodiments described in this application are only embodiments of a part of the present invention, rather than all embodiments. Based on the spirit of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work belong to the protection scope of the present invention.

[0060] like Figure 1 As shown in the figure, it is a main circuit control structure diagram of the virtual synchronous generator in the embodiment. The DC side power supply can be an energy storage power supply device. Here, a constant DC voltage source Udc The output of the converter is connected to the input of the LC filter and transmitted to the large power grid through the transmission line. The converter is controlled by a virtual synchronous generator (VSG).

[0061] First, the voltage and current of the VSG AC side output port are measured, and the measured values ​​are sent to the power calculation unit, and the active power P and reactive power Q output by the VSG are calculated; after the above power values ​​are calculated, they are sent to the power outer loop controller, and the phase angle and voltage amplitude are obtained through the active droop control loop, reactive droop control loop and inertia damping simulation; the reference voltage is calculated using the mathematical model of the synchronous generator, and a PWM pulse signal is generated through the voltage and current inner loop control and pulse width modulation to drive the opening and closing of the switching devices in the grid-connected converter, thereby achieving the purpose of changing the output voltage and current of the converter.

[0062] like Figure 2 In the VSG shown in the figure, the active power command P ref Add the primary frequency modulation power and then subtract the system steady-state active power P e , we can get the power difference ΔP, pass the power difference through the inertia link to get the angular frequency difference Δω, add the angular frequency difference Δω to the grid rated angular frequency ω0 to get the output angular frequency ω of the virtual synchronous generator, and subtract the grid frequency ω from the angular frequency ω g After integration, the output power angle δ is obtained. Among them, the angular frequency difference Δω forms negative feedback through the damping coefficient D.

[0063] The present invention proposes a grid-type energy storage power control method and system based on feedforward virtual damping regulation, wherein the control of the converter adopts a virtual synchronous generator; the method comprises:

[0064] Step 1, obtain the angular frequency difference and the output angular frequency.

[0065] Specifically, the angular frequency difference Δω satisfies the following relationship:

[0066]

[0067] Where, J is the virtual inertia coefficient; k p is the primary frequency modulation coefficient, s is the Laplace operator, P ref is the active power command, P e is the steady-state active power of the system.

[0068] Then the output angular frequency ω satisfies the following relationship:

[0069] ω=Δω+ω0

[0070] Where ω0 is the rated angular frequency of the power grid.

[0071] Step 2: Establish an adaptive adjustment model of the feedforward virtual damping coefficient based on the rate of change of the output angular frequency.

[0072] Specifically, the feedforward virtual damping coefficient k d The adaptive adjustment model satisfies the following relationship:

[0073]

[0074] In the formula, k d0 is the reference value of the feedforward virtual damping coefficient, a is the feedforward virtual damping adjustment coefficient, and b is the angular frequency change rate threshold.

[0075] The present invention introduces feedforward virtual damping adaptive control in the virtual synchronous generator, so the introduction of the feedforward virtual damping coefficient will change the equivalent damping of the virtual synchronous generator. When the power grid system is in a stable state, the corresponding embodiment is The reference value of the feedforward virtual damping coefficient makes the equivalent damping of the virtual synchronous generator 0.707. When a small disturbance occurs in the dynamic process of the power grid system, the corresponding embodiment is The feedforward virtual damping coefficient is increased according to the real-time change rate of the output angular frequency to achieve synchronous increase of the equivalent damping of the virtual synchronous generator. The present invention utilizes the active loop angular frequency deviation to feed forward to the closed-loop control loop of the grid-connected active power, and ensures the dynamic performance of the system active response by adjusting the introduced feedforward virtual damping coefficient; at the same time, a virtual damping adaptive control scheme is provided, which increases the virtual damping during the disturbance process to quickly suppress the active power oscillation.

[0076] Step 3, using the angular frequency difference and the feedforward virtual damping coefficient output by the modified adaptive adjustment model to obtain the power angle compensation amount.

[0077] Specifically, the power angle compensation amount δ d Satisfies the following relationship:

[0078] δ d =Δω·k d

[0079] Step 4: Use the difference between the output angular frequency and the grid frequency to obtain a power angle reference value, and use the sum of the power angle reference value and the power angle compensation amount as the output power angle.

[0080] Specifically, the power angle reference value satisfies the following relationship:

[0081]

[0082] In the formula, ω g is the grid frequency, δ g It is the power angle reference value.

[0083] The output power angle satisfies the following relationship:

[0084] δ=δ g +δ d

[0085] The modified adaptive adjustment model modifies the adaptive adjustment model of the feedforward virtual damping coefficient based on the minimum deviation of the system steady-state active power.

[0086] Step 5: Based on the output voltage amplitude and output power angle of the virtual synchronous generator, a reference voltage for input voltage and current inner loop control is obtained.

[0087] Specifically, when the damping coefficient of the traditional VSG is increased, a larger steady-state active power deviation will be brought about. Therefore, the present invention proposes a correction process of the adaptive adjustment model to ensure the steady-state performance of the system active response.

[0088] Specifically, the system steady-state active power satisfies the following relationship:

[0089]

[0090] In the formula, G PP,VDF-VSG (s) is the frequency domain expression of the first transfer function of the active power control loop, G Pω,VDF-VSG (s) is the frequency domain expression of the second transfer function of the active power control loop, P ref is the active power command, k p is the primary frequency modulation coefficient, s is the Laplace operator, P e is the system steady-state active power;

[0091] The first transfer function and the second transfer function of the active power control loop satisfy the following relationship:

[0092]

[0093] In the formula, G PP,VDF-VSG is the first transfer function of the active power control loop, G Pω,VDF-VSG is the second transfer function of the active power control loop, ΔP e is the system steady-state active power deviation, ΔP ref is the change in active power command, Δω g is the change of grid frequency, and K is the proportional coefficient of the transfer function.

[0094] Taking the minimum deviation of the steady-state active power of the system as the optimization goal, based on the first transfer function and the second transfer function of the active power control loop, the feedforward virtual damping adjustment coefficient a and the angular frequency change rate threshold b in the adaptive adjustment model of the feedforward virtual damping coefficient are iteratively solved to obtain the optimal value a of the feedforward virtual damping adjustment coefficient.* and the optimal value b of the angular frequency change rate threshold * ; Based on a * , b * , and obtain the modified adaptive adjustment model.

[0095] After the above correction process, the optimal value of the feedforward virtual damping adjustment coefficient is 0.025, and the optimal value of the angular frequency change rate threshold is 0.2.

[0096] The process of correcting the adaptive adjustment model of the feedforward virtual damping coefficient based on the minimum steady-state active power deviation of the system proposed in the present invention actually weakens the coupling between the primary frequency modulation coefficient and the damping coefficient D, realizes the coupling between the primary frequency modulation coefficient and the feedforward virtual damping coefficient, avoids a large steady-state active power deviation caused by increasing the damping coefficient, and can damp power oscillations faster when small disturbances occur in the system.

[0097] The block diagram of the active loop control of the virtual synchronous generator in the embodiment of the present invention is as follows: Figure 3 Based on Figure 3 The results of the active loop of the virtual synchronous generator shown in the figure are used to compare the method proposed by the present invention with the traditional VSG. First, the relevant simulation parameters are set. In this embodiment, the relevant parameters in the method proposed by the present invention are set as follows: the rated capacity of the grid-type energy storage controlled by the virtual synchronous generator is 2MW, the active power instruction is set to 1MW, the rated frequency of the grid is 50Hz, and the virtual inertia coefficient is 10kg·m 2 , the droop coefficient is 10000w / rad, the feedforward virtual damping adjustment coefficient is 0.025, and the optimal value of the angular frequency change rate threshold is 0.2. Set the simulation working conditions, the initial stable state, the active output command increases by 0.1MW at 3s; the grid frequency drops to 49.9Hz at 5s; during this period, the reactive power is constant at 0Mvar, and the total simulation time is 7s.

[0098] The comparison results of system active response under different control strategies are as follows: Figure 4As shown. When the traditional VSG zero damping coefficient control strategy is adopted, the system active power oscillates violently, the adjustment time is long, and the steady-state active power deviation is 6.28kW; when the traditional VSG damping coefficient is increased to 50, the system active power has no overshoot, and the system is in an over-damping ratio state, and the steady-state active power deviation increases to 16.15kW. From the simulation results of the traditional VSG with increased damping coefficient, although increasing the damping coefficient can improve the active dynamic response, the steady-state error increases, and the system's active response dynamic and steady-state performance cannot be taken into account, which verifies the problems of the traditional VSG control strategy. When the virtual damping feedforward method proposed in the present invention is adopted, the system active power overshoot is significantly reduced compared with the traditional VSG zero damping coefficient, and the steady-state active power deviation is 6.28kW, which is equivalent to the steady-state response performance of the traditional VSG zero damping coefficient strategy; when the feedforward virtual damping adaptive adjustment control method proposed in the present invention is adopted, the system active power overshoot is further reduced compared with the fixed feedforward damping coefficient strategy, and the system steady-state active power deviation is still 6.28kW, thereby achieving and optimizing the dynamic and steady-state performance of the system active response.

[0099] Figure 5 is a diagram of the damping variation of a virtual synchronous generator using the adaptive feedforward virtual damping proposed by the present invention in an example of the present invention. Figure 5 It can be seen that when the system is subjected to a small disturbance, the feedforward damping coefficient is rapidly and adaptively increased in the initial stage of the angular frequency change to damp the power oscillation, and the feedforward damping coefficient is adaptively reduced to the steady-state value when it tends to the steady state, so that the feedforward damping coefficient is adaptively adjusted according to the angular frequency change rate during the disturbance, thereby optimizing the dynamic response performance of the system.

[0100] The present invention also proposes a grid-type energy storage power control system based on feedforward virtual damping regulation, comprising:

[0101] Power angle compensation calculation module, output power angle calculation module, reference voltage calculation module, model correction module, reference voltage correction module;

[0102] A power angle compensation calculation module is used to obtain a power angle compensation by using an angular frequency difference and a feedforward virtual damping coefficient output by a modified adaptive adjustment model;

[0103] An output power angle calculation module is used to obtain a power angle reference value by using the difference between the output angular frequency and the grid frequency, and to use the sum of the power angle reference value and the power angle compensation amount as the output power angle;

[0104] The reference voltage calculation module is used to obtain the reference voltage for the input voltage and current inner loop control based on the output voltage amplitude and output power angle of the virtual synchronous generator.

[0105] The power angle compensation calculation module includes: a collection unit and an adaptive adjustment model unit;

[0106] An acquisition unit, used for acquiring an angular frequency difference and outputting an angular frequency;

[0107] The adaptive adjustment model unit is used to establish an adaptive adjustment model of the feedforward virtual damping coefficient based on the change rate of the output angular frequency.

[0108] The power angle compensation amount calculation module also includes: an adaptive adjustment model correction unit;

[0109] The adaptive adjustment model correction unit is used to correct the adaptive adjustment model of the feedforward virtual damping coefficient based on the minimum deviation of the system steady-state active power.

[0110] The present invention provides a grid-type energy storage power control method based on feedforward virtual damping regulation. By utilizing the active loop angular frequency deviation to feedforward to the grid-connected active closed-loop control loop, the dynamic and steady-state performance of the system active response can be taken into account by adjusting the introduced feedforward virtual damping coefficient; at the same time, a virtual damping adaptive control scheme is provided, and the virtual damping is increased during the disturbance process to quickly suppress the active power oscillation. At the same time, the present invention takes advantage of the flexible and adjustable VSG parameters, and the feedforward virtual damping coefficient uses an adaptive control algorithm. When the system is disturbed and causes frequency fluctuations, the damping coefficient value is adaptively adjusted according to the frequency change rate. The adaptive adjustment of the damping coefficient during the dynamic response process can quickly suppress power oscillations and frequency fluctuations, allowing the system to quickly tend to a stable state.

[0111] The present disclosure may be a system, a method and / or a computer program product. The computer program product may include a computer-readable storage medium carrying computer-readable program instructions for causing a processor to implement various aspects of the present disclosure.

[0112] A computer-readable storage medium may be a tangible device that can hold and store instructions used by an instruction execution device. A computer-readable storage medium may be, for example, but not limited to, an electrical storage device, a magnetic storage device, an optical storage device, an electromagnetic storage device, a semiconductor storage device, or any suitable combination of the foregoing. More specific examples of computer-readable storage media (a non-exhaustive list) include: a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), a static random access memory (SRAM), a portable compact disk read-only memory (CD-ROM), a digital versatile disk (DVD), a memory stick, a floppy disk, a mechanical encoding device, such as a punch card or a raised structure in a groove on which instructions are stored, and any suitable combination of the foregoing. As used herein, a computer-readable storage medium is not to be interpreted as a transient signal per se, such as a radio wave or other freely propagating electromagnetic wave, an electromagnetic wave propagating through a waveguide or other transmission medium (e.g., a light pulse through a fiber optic cable), or an electrical signal transmitted through a wire.

[0113] The computer-readable program instructions described herein can be downloaded from a computer-readable storage medium to each computing / processing device, or downloaded to an external computer or external storage device via a network, such as the Internet, a local area network, a wide area network, and / or a wireless network. The network can include copper transmission cables, optical fiber transmissions, wireless transmissions, routers, firewalls, switches, gateway computers, and / or edge servers. The network adapter card or network interface in each computing / processing device receives the computer-readable program instructions from the network and forwards the computer-readable program instructions for storage in the computer-readable storage medium in each computing / processing device.

[0114] The computer program instructions for performing the operation of the present disclosure may be assembly instructions, instruction set architecture (ISA) instructions, machine instructions, machine-related instructions, microcode, firmware instructions, state setting data, or source code or object code written in any combination of one or more programming languages, including object-oriented programming languages, such as Smalltalk, C++, etc., and conventional procedural programming languages, such as "C" language or similar programming languages. Computer-readable program instructions may be executed completely on a user's computer, partially on a user's computer, as an independent software package, partially on a user's computer, partially on a remote computer, or completely on a remote computer or server. In the case of a remote computer, the remote computer may be connected to the user's computer via any type of network, including a local area network (LAN) or a wide area network (WAN), or may be connected to an external computer (e.g., using an Internet service provider to connect via the Internet). In some embodiments, an electronic circuit, such as a programmable logic circuit, a field programmable gate array (FPGA), or a programmable logic array (PLA), may be customized by utilizing the state information of the computer-readable program instructions, and the electronic circuit may execute the computer-readable program instructions, thereby realizing various aspects of the present disclosure.

[0115] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the above embodiments, ordinary technicians in the relevant field should understand that the specific implementation methods of the present invention can still be modified or replaced by equivalents, and any modifications or equivalent replacements that do not depart from the spirit and scope of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. A grid-type energy storage power control method based on feedforward virtual damping regulation, characterized in that: include: The power angle compensation is obtained by using the angular frequency difference and the feedforward virtual damping coefficient output by the modified adaptive adjustment model; The power angle reference value is obtained by using the difference between the output angular frequency and the grid frequency, and the sum of the power angle reference value and the power angle compensation amount is used as the output power angle; Based on the output voltage amplitude and output power angle of the virtual synchronous generator, a reference voltage for input voltage and current inner loop control is obtained; The modified adaptive adjustment model modifies the adaptive adjustment model of the feedforward virtual damping coefficient based on the minimum deviation of the system steady-state active power.

2. The grid-type energy storage power control method based on feedforward virtual damping regulation according to claim 1 is characterized in that: The power angle compensation is obtained by using the angular frequency difference and the feedforward virtual damping coefficient output by the modified adaptive adjustment model, including: Obtain the angular frequency difference and output angular frequency; The angular frequency difference Δω satisfies the following relationship: The output angular frequency ω satisfies the following relationship: ω=Δω+ω0 Where, J is the virtual inertia coefficient; k p is the primary frequency modulation coefficient, s is the Laplace operator, P ref is the active power command, P e is the steady-state active power of the system, and ω0 is the rated angular frequency of the power grid.

3. The grid-type energy storage power control method based on feedforward virtual damping regulation according to claim 2 is characterized in that: The power angle compensation is obtained by using the angular frequency difference and the feedforward virtual damping coefficient output by the modified adaptive adjustment model, including: An adaptive adjustment model of the feedforward virtual damping coefficient is established based on the change rate of the output angular frequency; Feedforward virtual damping coefficient k d The adaptive adjustment model satisfies the following relationship: In the formula, k d0 is the reference value of the feedforward virtual damping coefficient, a is the feedforward virtual damping adjustment coefficient, and b is the angular frequency change rate threshold.

4. The grid-type energy storage power control method based on feedforward virtual damping regulation according to claim 3 is characterized in that: Characterizing that the power grid system is in a stable state, the baseline value of the feedforward virtual damping coefficient makes the equivalent damping of the virtual synchronous generator 0.

707.

5. The grid-type energy storage power control method based on feedforward virtual damping regulation according to claim 3 is characterized in that: Power angle compensation δ d Satisfies the following relationship: d d =Give me k d Power angle reference value δ g Satisfies the following relationship: The output power angle δ satisfies the following relationship: d=d g +d d In the formula, ω g is the grid frequency.

6. The grid-type energy storage power control method based on feedforward virtual damping regulation according to claim 3 is characterized in that: The modified adaptive adjustment model is based on the minimum system steady-state active power deviation, and modifies the adaptive adjustment model of the feedforward virtual damping coefficient, including: Taking the minimum deviation of the steady-state active power of the system as the optimization goal, based on the first transfer function and the second transfer function of the active power control loop, the feedforward virtual damping adjustment coefficient a and the angular frequency change rate threshold b in the adaptive adjustment model of the feedforward virtual damping coefficient are iteratively solved to obtain the optimal value a of the feedforward virtual damping adjustment coefficient. * and the optimal value b of the angular frequency change rate threshold * ; Based on a * 、b * , and obtain the modified adaptive adjustment model.

7. The grid-type energy storage power control method based on feedforward virtual damping regulation according to claim 6 is characterized in that: The first transfer function and the second transfer function of the active power control loop satisfy the following relationship: In the formula, G PP,VDF-VSG is the first transfer function of the active power control loop, G Pω,VDF-VSG is the second transfer function of the active power control loop, ΔP e is the system steady-state active power deviation, ΔP ref is the change in active power command, Δω g is the change of grid frequency, and K is the proportional coefficient of the transfer function.

8. The grid-type energy storage power control method based on feedforward virtual damping regulation according to claim 7 is characterized in that: The system steady-state active power satisfies the following relationship: In the formula, G PP,VDF-VSG (s) is the frequency domain expression of the first transfer function of the active power control loop, G Pω,VDF-VSG (s) is the frequency domain expression of the second transfer function of the active power control loop.

9. The grid-type energy storage power control method based on feedforward virtual damping regulation according to claim 6 is characterized in that: The feedforward virtual damping adjustment coefficient is 0.025, and the angular frequency change rate threshold is 0.

2.

10. A grid-type energy storage power control system based on feedforward virtual damping regulation, characterized in that: include: Power angle compensation calculation module, output power angle calculation module, reference voltage calculation module, model correction module, reference voltage correction module; A power angle compensation calculation module is used to obtain a power angle compensation by using an angular frequency difference and a feedforward virtual damping coefficient output by a modified adaptive adjustment model; An output power angle calculation module is used to obtain a power angle reference value by using the difference between the output angular frequency and the grid frequency, and to use the sum of the power angle reference value and the power angle compensation amount as the output power angle; The reference voltage calculation module is used to obtain the reference voltage for the input voltage and current inner loop control based on the output voltage amplitude and output power angle of the virtual synchronous generator.

11. The grid-type energy storage power control system based on feedforward virtual damping regulation according to claim 10, characterized in that: The power angle compensation calculation module includes: a collection unit and an adaptive adjustment model unit; An acquisition unit, used for acquiring an angular frequency difference and outputting an angular frequency; The adaptive adjustment model unit is used to establish an adaptive adjustment model of the feedforward virtual damping coefficient based on the change rate of the output angular frequency.

12. The grid-type energy storage power control system based on feedforward virtual damping regulation according to claim 10, characterized in that: The power angle compensation amount calculation module also includes: an adaptive adjustment model correction unit; The adaptive adjustment model correction unit is used to correct the adaptive adjustment model of the feedforward virtual damping coefficient based on the minimum deviation of the system steady-state active power.

13. A terminal comprising a processor and a storage medium; characterized in that: The storage medium is used to store instructions; The processor is configured to operate according to the instructions to execute the steps of the method according to any one of claims 1 to 9.

14. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the program is executed by a processor, the steps of the method according to any one of claims 1 to 9 are implemented.

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