Method and system for suppressing power oscillation of networking type diesel-storage combined power supply system

Abstract

The invention discloses a power oscillation suppression method and system for a network-forming type diesel-storage combined power supply system, and the method comprises the steps: introducing the instantaneous active power of a diesel generator and an energy storage converter into an instantaneous power interleaving feedback compensation branch, calculating to obtain the power angle compensation amount of the energy storage converter, and carrying out the real-time adjustment of the output phase of the energy storage converter, therefore, the phase deviation between the energy storage converter and the diesel generator is reduced, the purpose of suppressing the power oscillation of the network-forming type diesel-storage combined power supply system is achieved, and the cooperative power supply capability of the network-forming type diesel-storage combined power supply system under the dynamic working condition is remarkably improved.

Description

Technical Field

[0001] The present invention relates to the field of microgrid operation and stability control, and particularly to a method and system for suppressing power oscillation of a grid-forming diesel and energy storage combined power supply system. Background Art

[0002] In remote areas such as islands, deserts, and rural areas, a grid-forming diesel and energy storage parallel system composed of a diesel generator and an energy storage converter with grid-forming control is often adopted to replace the large power grid to provide reliable power supply. While ensuring power supply stability and reliability, it also avoids the high cost of large-scale power grid construction and overcomes the inherent defects of single diesel power generation such as low flexibility, poor economy, and slow response speed. It is an important means to ensure power supply in the above-mentioned areas. In the above system, the energy storage converter can cooperate with the diesel generator to share the load power change according to the preset droop coefficient, thus significantly reducing the capacity requirement of the diesel generator and helping to stabilize the system frequency. However, due to the large differences in physical structure and control parameters between the diesel generator and the energy storage converter, the parallel system often exhibits power oscillation problems when facing load power shocks.

[0003] Regarding the method for suppressing power oscillation of a grid-forming diesel and energy storage combined power supply system, some scholars have proposed some solutions:

[0004] The prior art has proposed an active oscillation suppression strategy for a diesel and energy storage microgrid (Shi Rongliang, Wang Guobin, Lan Caihua, et al. Active oscillation suppression strategy for a diesel and energy storage microgrid based on active proportional differential feedforward VSG [J]. Renewable Energy, 2024, 42(08): 1074-1082). However, the response speed of the oscillation suppression strategy proposed in this scheme is affected by the original control parameters of the converter, and the used differential link is not easy to be implemented in a discrete controller, nor is it applicable to the case where there are large differences in the capacities of the diesel generator and the energy storage converter.

[0005] Another study has proposed two oscillation suppression strategies for a diesel and energy storage parallel system with pulse loads (Yi Weilang. Research on key technologies of multi-channel synchronous power supply for special power sources under periodic impact loads [D]. Hunan University, 2023). However, the angular acceleration parameter of the diesel generator used in the control strategy proposed in this scheme is difficult to measure quickly and accurately.

[0006] The patent application with the publication number CN119134389A proposes a method for suppressing oscillations in a grid-forming diesel-storage parallel system under low-frequency impact loads. However, the implementation of this method depends on accurately obtaining the instantaneous values of the load power parameters. Restricted by the wide geographical distribution characteristics between distributed power sources and impact loads at oilfield operation sites, coupled with engineering constraints such as system communication delays and measurement errors, the control scheme based on real-time load power tracking has significant limitations in practical engineering applications. In addition, the above oscillation suppression method is not applicable to three-phase non-linear and asymmetric loads.

[0007] In summary, the existing methods are difficult to balance fast response and engineering feasibility. There is an urgent need for a new power oscillation suppression strategy with fast response and strong engineering feasibility to improve the coordinated power supply ability of the grid-forming diesel-storage combined power supply system under dynamic conditions. Summary of the Invention

[0008] The technical problem to be solved by the present invention is to provide a method and system for suppressing power oscillations in a grid-forming diesel-storage combined power supply system, aiming at the deficiencies of the existing technology, and solving the power oscillation problem caused by differences in physical structures and control parameters between diesel generators and energy storage converters.

[0009] To solve the above technical problem, the technical solution adopted by the present invention is: a method for suppressing power oscillations in a grid-forming diesel-storage combined power supply system, including the following steps:

[0010] Sample the instantaneous values u vga 、u vgb 、u vgc of the three-phase output voltage and the instantaneous values i vga 、i vgb 、i vgc of the three-phase current output by the energy storage converter. Calculate the instantaneous active power P vga 、u vgb 、u vgc and the instantaneous reactive power Q vga 、i vgb 、i vgc of the energy storage converter according to the instantaneous values u vg and the instantaneous values i vg of the three-phase output voltage and the three-phase current output by the energy storage converter;

[0011] Sample the instantaneous values u dga 、u dgb 、u dgc of the three-phase output voltage of the diesel generator;

[0012] Use the phase θ vg of the output voltage of the energy storage converter and the instantaneous values u dga 、u dgb, u dgc Calculate the phase compensation amount θ of the energy storage converter a ;

[0013] Utilize the instantaneous active power P vg and the instantaneous reactive power Q vg of the energy storage converter, as well as the phase compensation amount θ a to calculate the amplitude E vg and the phase θ vg of the output voltage of the energy storage converter;

[0014] Subject the amplitude E vg and the phase θ vg of the output voltage of the energy storage converter to PWM modulation to generate the drive signal K PWM .

[0015] The present invention utilizes the phase θ vg of the energy storage converter and the instantaneous values u dga , u dgb , u dgc of the three-phase output voltage of the diesel generator to calculate the phase compensation amount θ a , which can effectively suppress the power oscillation problem caused by the phase inconsistency of the parallel units. The present invention can reduce the phase deviation between the energy storage converter and the diesel generator set by actively compensating the phase of the energy storage converter, thereby suppressing the power oscillation. The present invention does not need to obtain the instantaneous value parameters of the load power, and the implementation of the scheme is not limited by the use place, greatly improving the engineering practicability of the scheme. The present invention only needs to collect the instantaneous values of the three-phase output voltage of the diesel generator to effectively suppress the power oscillation, without the need to configure a current detection unit. This simplified design reduces the number of sampling units, significantly improving the reliability and economy of the system.

[0016] In the present invention, the calculation formula for the phase compensation amount θ a is as follows: ; where u dga , u dgb and u dgc are respectively the instantaneous values of the three-phase output voltage of the A-phase, B-phase and C-phase of the diesel generator, and K a is the compensation proportionality coefficient.

[0017] The phase compensation amount of the present invention is calculated from the instantaneous values of the three-phase output voltage of the diesel generator and the phase of the grid-forming inverter. Therefore, only through voltage and phase operations, it has the ability to suppress oscillations in typical three-phase unbalanced and nonlinear load scenarios, and can effectively avoid the influence of current distortion on the oscillation suppression effect in the above scenarios, significantly improving the robustness of the proposed method.

[0018] In the present invention, the calculation formula for the amplitude E vg of the output voltage of the energy storage converter is as follows: ; where, K q , U vgn , Q vgn and D q are respectively the excitation regulation coefficient, rated voltage, rated reactive power and reactive power droop coefficient of the energy storage converter.

[0019] The phase θ vg of the output voltage of the energy storage converter is calculated by the formula: ; J, D p and ω vgn are respectively the virtual inertia, active power droop coefficient and rated angular frequency of the energy storage converter, and P vgn is the rated active power of the energy storage converter.

[0020] As an inventive concept, the present invention also provides a power oscillation suppression system for a grid-connected diesel and energy storage combined power supply system, including:

[0021] A first sampling unit for sampling the instantaneous values u vga , u vgb , u vgc of the three-phase output voltage and the three-phase currents i vga , i vgb , i vgc output by the energy storage converter, and calculating the instantaneous active power P vga , u vgb , u vgc of the energy storage converter according to the instantaneous values u vga , i vgb , i vgc of the three-phase output voltage and the three-phase currents i vg and instantaneous reactive power Q vg ;

[0022] A second sampling unit for sampling the instantaneous values u dga , u dgb , u dgc of the three-phase output voltage output by the diesel generator;

[0023] A phase compensation amount calculation unit for calculating the phase compensation amount θ vg of the energy storage converter by using the phase θ dga , u dgb , u dgc of the output voltage of the energy storage converter and the instantaneous values u a ;

[0024] An amplitude calculation unit for calculating the amplitude E vg of the output voltage of the energy storage converter by using the instantaneous reactive power Q vg of the energy storage converter;

[0025] A phase calculation unit, configured to use the instantaneous active power P of the energy storage converter vg and the phase compensation amount θ a to calculate the phase θ of the output voltage of the energy storage converter vg ;

[0026] A modulation unit, configured to perform PWM modulation on the amplitude E and the phase θ of the output voltage of the energy storage converter vg to generate a drive signal K vg PWM .

[0027] The phase compensation amount calculation unit calculates the phase compensation amount θ using the following formula a : ; where P dgn and P vgn are respectively the rated active power of the diesel generator and the rated active power of the energy storage converter, and K a and K f are the compensation ratio coefficient and the compensation feedback coefficient.

[0028] The amplitude calculation unit calculates the amplitude E of the output voltage of the energy storage converter using the following formula vg : ; where K q , U vgn , Q vgn and D q are respectively the excitation regulation coefficient, the rated voltage, the rated reactive power and the reactive power droop coefficient of the energy storage converter.

[0029] The phase calculation unit calculates the phase θ of the output voltage of the energy storage converter using the following formula vg : ; J , D p and ω vgn are respectively the virtual inertia, the active power droop coefficient and the rated angular frequency of the energy storage converter, P vgn is the rated active power of the energy storage converter.

[0030] As an inventive concept, the present invention further provides a grid-forming diesel-electricity and energy storage combined power supply control system, including one or more processors and a memory; one or more programs are stored on the memory, and when the one or more programs are executed by the one or more processors, the one or more processors are caused to implement the steps of the above method.

[0031] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0032] ​(1) The present invention introduces an instantaneous phase feedback compensation branch into the control system of the energy storage converter, which can effectively suppress the power oscillation of the grid-forming diesel and energy storage combined power supply system.

[0033] (2) While realizing the suppression of power oscillation in the grid-forming diesel and energy storage combined power supply system, the present invention does not require any additional adjustment to the control system of the diesel generator. In addition, the present invention does not need to simultaneously collect voltage and current information to calculate the load power, with fewer sampling units, and both the program complexity and implementation difficulty are reduced.

[0034] (3) The compensation parameter K of the proposed method a is set with a certain adjustable window and does not rely on complex and precise calculations. In addition, the additional branch is set in parallel with the original control loop. Therefore, the oscillation suppression effect of the proposed control is not affected by the change of the original control parameters of the VSG, improving the robustness and deployment convenience of the method.

[0035] (4) While realizing the suppression of power oscillation in the grid-forming diesel and energy storage combined power supply system, the present invention does not change the steady-state power distribution of the diesel generator and the energy storage converter. Description of the Drawings

[0036] Figure 1 is a schematic diagram of the structure of the diesel-energy storage multi-port power supply system in the embodiment of the present invention;

[0037] Figure 2 is a schematic diagram of the principle of the method for suppressing power oscillation of the grid-forming diesel and energy storage combined power supply in the embodiment of the present invention;

[0038] Figure 3 is a control block diagram of the instantaneous power interleaved feedback compensation branch in the embodiment of the present invention;

[0039] Figure 4 is a simulation waveform diagram of the output power of the grid-forming diesel and energy storage combined power supply system when the traditional control method is adopted in the embodiment of the present invention;

[0040] Figure 5 is a simulation waveform diagram of the output power of the grid-forming diesel and energy storage combined power supply system when the oscillation suppression method is adopted in the embodiment of the present invention. Specific Embodiments

[0041] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0042] Embodiment 1

[0043] As shown Figure 1 in the figure, the structure of the diesel - energy storage multi - port power supply system under low - frequency pulse load in the embodiment of the present invention includes a diesel generator and at least one energy storage converter. In Figure 1 , X dg1 is the output impedance of the diesel generator; X vg1 ~X vgn are the output impedances of the first to the nth energy storage converters; both the diesel generator and the energy storage converters are connected to the same AC bus through the output impedances and the load, and the load includes a conventional load and a dynamic load.

[0044] As shown Figure 2 in the figure, the method for suppressing the power oscillation of the grid - forming diesel - energy storage combined power supply in the embodiment of the present invention includes the following steps.

[0045] Step 1, Sampling and power calculation.

[0046] Step 1.1 Sample the instantaneous values of the three - phase output voltages u vga , u vgb , u vgc and the three - phase currents i vga , i vgb , i vgc output by the energy storage converter. Calculate the instantaneous active power P vga , u vgb , u vgc and the three - phase currents i vga , i vgb , i vgc of the energy storage converter according to the instantaneous values of the three - phase output voltages u vg and the instantaneous reactive power Q vg ;

[0047] Step 1.2 Sample the instantaneous values of the three - phase output voltages u dga , u dgb , u dgc output by the diesel generator.

[0048] Step 2, Phase compensation amount calculation.

[0049] Introduce the phase θ vg calculated in Step 1 and the instantaneous values of the three - phase output voltages u dga , u dgb , u dgc into the deviation phase feedback compensation branch to calculate the phase compensation amount θ a of the energy storage converter. The specific calculation formula is: ; where, u dga , u dgband u dgc are the instantaneous values of the three-phase output voltages of the A-phase, B-phase, and C-phase of the diesel generator, respectively. K a is the compensation ratio coefficient.

[0050] Step 3: Calculate the amplitude and phase of the output voltage.

[0051] Using the instantaneous active power P vg and instantaneous reactive power Q vg calculated in Step 1, and the phase compensation amount θ a of the energy storage converter calculated in Step 2, calculate the amplitude E vg and phase θ vg of the output voltage of the energy storage converter. The specific calculation formula is: ; where K q , U vgn , Q vgn and D q are the excitation regulation coefficient, rated voltage, rated reactive power, and reactive droop coefficient of the energy storage converter, respectively; J, D p and ω vgn are the virtual inertia, active droop coefficient, and rated angular frequency of the energy storage converter, respectively.

[0052] Step 4: Generate the drive signal.

[0053] After PWM modulation of the amplitude E vg and phase θ vg of the output voltage of the energy storage converter calculated in Step 3, generate the drive signal K PWM .

[0054] As Figure 3 shown, in the instantaneous phase feedback compensation branch of the embodiment of the present invention, the instantaneous values u dga , u dgb , u dgc of the three-phase output voltages of the diesel generator are input quantities. After introducing the instantaneous phase feedback compensation branch and calculating by combining the instantaneous values u dga , u dgb , u dgc of the three-phase output voltages with the phase θ vg of the output voltage of the energy storage converter, the generated phase compensation amount θ a , the specific calculation formula is: ; After arrangement, it can be obtained: ; where U dgis the amplitude of the output voltage of the diesel generator, which can generally be regarded as constant. It can be seen that when θ dg < θ vg , θ a is positive, and vice versa, it is negative. In addition, in the instantaneous phase feedback compensation branch, the larger K a , the more significant the effect of the instantaneous phase feedback compensation branch.

[0055] The reason for the power oscillation of this system is that the output phases of the diesel generator and the energy storage inverter are inconsistent. When θ dg > θ vg , it indicates that the output power P vg of the energy storage converter is insufficient; on the contrary, when θ dg < θ vg , the output power P vg of the energy storage converter is too high. Therefore, when there is power oscillation in the grid-forming diesel and energy storage combined power supply system, causing θ dg > θ vg , θ a will rise, increasing the output voltage phase θ vg of the energy storage converter, and then the instantaneous active power P vg of the energy storage converter can be increased; on the contrary, when there is power oscillation in the grid-forming diesel and energy storage combined power supply system, causing θ dg < θ vg , θ a will drop, reducing the output voltage phase θ vg of the energy storage converter, and then the instantaneous active power P vg of the energy storage converter can be reduced; when there is no power oscillation in the grid-forming diesel and energy storage combined power supply system, θ dg = θ vg , and at this time θ a will remain at zero, ensuring that the steady-state output powers of the diesel generator and the energy storage converter are not affected by the phase compensation amount θ a .

[0056] As Figure 4 shown, in the output power simulation model diagram of the grid-forming diesel and energy storage combined power supply system when using the traditional control method, after the load power suddenly increases from 10 kW to 30 kW, there are obvious oscillations in the output powers of both the diesel generator and the energy storage converter. The amplitude of the power oscillation is 5.1 kW. After the oscillation ends, the steady-state values of the instantaneous active powers of the diesel generator and the energy storage converter are 20 kW and 10 kW respectively.

[0057] As Figure 5As shown in the simulation model diagram of the output power of the network-forming diesel and energy storage combined power supply system when the oscillation suppression method is adopted in this embodiment, when the load power suddenly increases from 10 kW to 30 kW, the amplitude of the power oscillation in the instantaneous active power of the diesel generator and the energy storage converter is significantly suppressed, and the amplitude of the power oscillation drops to 0.8 kW. After the oscillation ends, the steady-state values of the instantaneous active power of the diesel generator and the energy storage converter are 20 kW and 10 kW respectively. The above results show that the oscillation suppression method of this embodiment can effectively suppress the power oscillation of the network-forming diesel and energy storage combined power supply system without affecting the steady-state values of the instantaneous active power of the diesel generator and the energy storage converter.

[0058] Embodiment 2

[0059] This embodiment provides a power oscillation suppression system for a network-forming diesel and energy storage combined power supply system, including:

[0060] A first sampling unit for sampling the instantaneous values u of the three-phase output voltage output by the energy storage converter vgabc and the three-phase current i vgabc , and calculating the instantaneous active power P of the energy storage converter according to the instantaneous values u of the three-phase output voltage output by the energy storage converter vgabc and the three-phase current i vgabc and the instantaneous reactive power Q vg ; vg ;

[0061] A second sampling unit for sampling the instantaneous values u of the three-phase output voltage output by the diesel generator dga , u dgb , u dgc ;

[0062] A phase compensation amount calculation unit for calculating the phase compensation amount θ of the energy storage converter by using the phase θ of the energy storage converter vg and the instantaneous values u of the three-phase output voltage output by the diesel generator dga , u dgb , u dgc ; a ; where u , u dga , and u dgb and u dgc are the instantaneous values of the instantaneous values of the three-phase output voltages of the A phase, B phase, and C phase of the diesel generator respectively, and K a is the compensation proportionality coefficient; An amplitude calculation unit for calculating the amplitude E of the output voltage of the energy storage converter by using the instantaneous reactive power Q of the energy storage converter vg ; vg ; A phase calculation unit for using the instantaneous active power P of the energy storage converter vg and the phase compensation amount θ aCalculate the phase θ of the output voltage of the energy storage converter vg ; A modulation unit for amplifying the amplitude E of the output voltage of the energy storage converter vg and the phase θ vg through PWM modulation to generate a drive signal K PWM .

[0063] In this embodiment, ; where K q , U vgn , Q vgn and D q are respectively the excitation regulation coefficient, rated voltage, rated reactive power and reactive droop coefficient of the energy storage converter; J, D p and ω vgn are respectively the virtual inertia, active droop coefficient and rated angular frequency of the energy storage converter.

[0064] Embodiment 3

[0065] Embodiment 3 of the present invention provides a control system corresponding to Embodiment 1 above, including a memory, a processor, and a computer program stored on the memory; the processor executes the computer program on the memory to implement the steps of the method in Embodiment 1 above.

[0066] In some implementations, the memory may be a high-speed random access memory (RAM: Random Access Memory), and may also include non-volatile memory, such as at least one disk memory.

[0067] In other implementations, the processor may be a general-purpose processor of various types such as a central processing unit (CPU), a digital signal processor (DSP), etc., which are not limited herein.

[0068] Embodiment 4

[0069] Embodiment 4 of the present invention provides a computer-readable storage medium corresponding to Embodiment 1 above, on which computer programs / instructions are stored. When the computer programs / instructions are executed by a processor, the steps of the method in Embodiment 1 above are implemented.

[0070] A computer-readable storage medium may be a tangible device that holds and stores 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 combination of the above.

[0071] Those skilled in the art should understand that the embodiments of the present application can be provided as a method, a system, or a computer program product. Therefore, the present application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Moreover, the present application can take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) that contain computer-usable program code. The solutions in the embodiments of the present application can be implemented in various computer languages. For example, object-oriented programming languages such as Java and interpreted scripting languages such as JavaScript, etc.

[0072] The present application is described with reference to the flowcharts and / or block diagrams of methods, apparatuses (systems), and computer program products according to the embodiments of the present application. It should be understood that each flow and / or block in the flowchart and / or block diagram, as well as the combination of flows and / or blocks in the flowchart and / or block diagram, can be realized by computer program instructions. These computer program instructions can be provided to the processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing devices to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing devices generate means for realizing the functions specified in one Figure 1 flow or multiple flows and / or blocks Figure 1 or multiple blocks.

[0073] These computer program instructions can also be loaded onto a computer or other programmable data processing devices, so that a series of operation steps are executed on the computer or other programmable devices to generate a computer-implemented process. Thus, the instructions executed on the computer or other programmable devices provide steps for realizing the functions specified in one Figure 1 flow or multiple flows and / or blocks Figure 1 or multiple blocks.

[0074] Although the preferred embodiments of the present application have been described, those skilled in the art can make additional changes and modifications to these embodiments once they learn the basic creative concepts. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications falling within the scope of the present application.

[0075] Obviously, those skilled in the art can make various changes and modifications to the present application without departing from the spirit and scope of the present application. Thus, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalent technologies, the present application is also intended to include these changes and modifications.

Claims

1. A method for suppressing power oscillation of a network-forming combined diesel and energy storage power supply system, characterized in that, including the following steps: The instantaneous values u of the three-phase output voltage output by the sampling energy storage converter vga 、u vgb 、u vgc and the three-phase currents i vga 、i vgb 、i vgc , according to the instantaneous values u of the three-phase output voltage output by the energy storage converter vga 、u vgb 、u vgc and the three-phase currents i vga 、i vgb 、i vgc calculate the instantaneous active power P of the energy storage converter vg and the instantaneous reactive power Q vg ; Sampling the instantaneous values u dga 、u dgb 、u dgc ; Using the phase θ of the output voltage of the energy storage converter vg and the instantaneous values u dga 、u dgb 、u dgc of the three-phase output voltage output by the diesel generator to calculate the phase compensation amount θ a ; Using the instantaneous active power P of the energy storage converter vg , the instantaneous reactive power Q vg and the phase compensation amount θ a to calculate the amplitude E of the output voltage of the energy storage converter vg and the phase θ vg ; The amplitude E of the output voltage of the energy storage converter vg and the phase θ vg are modulated by PWM to generate the drive signal K PWM .

2. The power oscillation suppression method of the network-forming combined diesel and energy storage power supply system according to claim 1, wherein Phase compensation amount θ a The calculation formula is as follows: ; where, u dga , u dgb and u dgc are respectively the instantaneous values of the three-phase output voltages of the A-phase, B-phase, and C-phase of the diesel generator, and K a is the compensation ratio coefficient.

3. The power oscillation suppression method for the network-forming combined power supply system of diesel and energy storage according to claim 1, wherein The amplitude E of the output voltage of the energy storage converter vg The calculation formula is as follows: ； Among them, K q , U vgn , Q vgn and D q are the excitation regulation coefficient, rated voltage, rated reactive power and reactive power droop coefficient of the energy storage converter, respectively.

4. The power oscillation suppression method for the network-forming combined power supply system of diesel and energy storage according to claim 1, wherein, The phase θ of the output voltage of the energy storage converter vg The calculation formula is as follows: ; J, D p and ω vgn are respectively the virtual inertia, active droop coefficient and rated angular frequency of the energy storage converter, and P vgn is the rated active power of the energy storage converter.

5. A power oscillation suppression system for a network-constructing combined power supply system of diesel and energy storage, characterized in that, including: The first sampling unit is used to sample the instantaneous values \(u\) of the three-phase output voltage output by the energy storage converter vga 、\(u\) vgb 、\(u\) vgc and the three-phase currents \(i\) vga 、\(i\) vgb 、\(i\) vgc and calculate the instantaneous active power \(P\) of the energy storage converter according to the instantaneous values \(u\) vga 、\(u\) vgb 、\(u\) vgc of the three-phase output voltage output by the energy storage converter and the three-phase currents \(i\) vga 、\(i\) vgb 、\(i\) vgc and the instantaneous reactive power \(Q\) vg ; vg ; The second sampling unit is used to sample the instantaneous values u dga 、u dgb 、u dgc ; A phase compensation amount calculation unit for calculating the phase compensation amount θ of the energy storage converter by using the phase θ of the output voltage of the energy storage converter vg and the instantaneous values u dga , u dgb , u dgc of the three-phase output voltage output a ; An amplitude calculation unit for calculating the amplitude E of the output voltage of the energy storage converter by using the instantaneous reactive power Q of the energy storage converter vg vg ;​ A phase calculation unit for calculating the phase θ of the output voltage of the energy storage converter by using the instantaneous active power P of the energy storage converter vg and the phase compensation amount θ a vg ;​ Modulation unit, used to modulate the amplitude E of the output voltage of the energy storage converter vg and the phase θ vg through PWM modulation to generate a drive signal K PWM .

6. The power oscillation suppression system of the network-forming combined power supply system of diesel and energy storage according to claim 5, characterized in that, The phase compensation amount calculation unit calculates the phase compensation amount θ using the following formula a : ; where u dga , u dgb and u dgc are respectively the instantaneous values of the three-phase output voltages of the A-phase, B-phase, and C-phase of the diesel generator, and K a is the compensation ratio coefficient.

7. The power oscillation suppression system of the network-forming combined power supply system of diesel and energy storage according to claim 5, wherein The amplitude calculation unit calculates the amplitude E of the output voltage of the energy storage converter using the following formula vg :[[]]END]] ； Among them, K q , U vgn , Q vgn and D q are the excitation regulation coefficient, rated voltage, rated reactive power and reactive power droop coefficient of the energy storage converter, respectively.

8. The power oscillation suppression system of the network-forming combined power supply system of diesel generator and energy storage according to claim 5, characterized in that, The phase calculation unit calculates the phase θ of the output voltage of the energy storage converter by using the following formula vg : ; J, D p and ω vgn are the virtual inertia, active power droop coefficient and rated angular frequency of the energy storage converter respectively, and P vgn is the rated active power of the energy storage converter.

9. A power grid-forming combined diesel and energy storage power supply control system, characterized in that, including one or more processors and a memory; one or more programs are stored on the memory, and when the one or more programs are executed by the one or more processors, the one or more processors are caused to implement the steps of the method according to any one of claims 1 to 4.

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