Electric power system and inertia adjusting method thereof

Abstract

The invention provides an electric power system and an inertia adjusting method thereof.The electric power system comprises a synchronous generator, a distributed energy storage device, a flywheel unit, a transformer and a controller, the synchronous generator, the distributed energy storage device and the flywheel unit are all connected to one end of the transformer, and the other end of the transformer is connected with a power grid; the transformer is used for adjusting the voltage flowing into a power grid, the controller is connected with the synchronous generator and the flywheel unit, and the controller is configured to obtain the current inertia of the power system; according to the inertia adjustment strategy, an inertia adjustment mode for the power system is determined through the current inertia, the inertia adjustment mode is used for indicating that the inertia of the power system is changed through at least one inertia device of the power system, and the inertia device comprises a synchronous generator and a flywheel unit; and executing an inertia adjustment mode to balance the inertia of the power system.

Description

Technical Field

[0001] The present application relates to the technical field of power systems, and in particular to a power system and an inertia regulation method thereof. Background Art

[0002] Distributed power generation includes renewable energy generation, which generally includes wind power generation, photovoltaic power generation, etc. As a result, the power system will gradually access inverters that use distributed power sources, and the number of synchronous generators (SG, Synchronous Generator) in the power system will gradually decrease. The reduction of synchronous generators is likely to cause a reduction in the overall inertia of the power system, leading to problems such as a decrease in system stability when a grid disturbance occurs. Summary of the invention

[0003] In view of this, the purpose of the present application is to at least provide an electric power system and an inertia regulation method thereof, by adding a flywheel unit to the inertia device of the electric power system, and by monitoring the current inertia of the electric power system, determining the inertia regulation method corresponding to the current inertia according to the inertia regulation strategy, thereby regulating the inertia of the electric power system through the inertia device in the electric power system, solving the technical problem of poor stability of the energy storage system caused by inertia instability in the prior art, and achieving the technical effect of improving the stability of the energy storage system.

[0004] This application mainly includes the following aspects:

[0005] In a first aspect, an embodiment of the present application provides an electric power system, comprising a synchronous generator, a distributed energy storage device, a flywheel unit, a transformer and a controller, wherein the synchronous generator, the distributed energy storage device and the flywheel unit are all connected to one end of the transformer, and the other end of the transformer is connected to a power grid, and the transformer is used to adjust the voltage flowing into the power grid, and the controller is connected to the synchronous generator and the flywheel unit, wherein the controller is configured to: obtain the current inertia of the electric power system; determine the inertia adjustment method for the electric power system according to the current inertia according to the inertia adjustment strategy, and the inertia adjustment method is used to indicate that the inertia of the electric power system is changed by at least one inertial device of the electric power system, and the inertial device includes the synchronous generator and the flywheel unit; and execute the inertia adjustment method to balance the inertia of the electric power system.

[0006] Optionally, the inertia adjustment method is used to indicate changing the mechanical power of the power system by controlling at least one inertial device of the power system to change the inertia of the power system, wherein the inertia adjustment method includes: an inertia increase adjustment method for increasing the inertia by increasing the mechanical power of the power system, or an inertia decrease adjustment method for reducing the inertia by reducing the mechanical power of the power system.

[0007] Optionally, the synchronous generator includes multiple ones, and the mechanical power of the power system is changed in the following manner: obtaining the current state of the flywheel unit and multiple synchronous generators of the power system, the current state including the working state and the non-working state, adjusting the flywheel unit in the non-working state to the working state and / or adjusting the synchronous generator in the non-working state to the working state, so as to increase the mechanical power of the power system; adjusting the flywheel unit in the working state to the non-working state and / or adjusting the synchronous generator in the working state to the non-working state, so as to reduce the mechanical power of the power system.

[0008] Optionally, the inertia adjustment strategy includes: determining whether the current inertia belongs to a preset inertia interval; if the current inertia belongs to the preset inertia interval, no inertia adjustment is performed on the power system; if the current inertia does not belong to the preset inertia interval, determining the inertia adjustment method for the power system based on the target inertia interval to which the current inertia belongs.

[0009] Optionally, the target inertia interval includes a high inertia interval greater than an upper limit value of the preset inertia interval or a low inertia interval less than a lower limit value of the preset inertia interval, and the inertia adjustment method includes an inertia increase adjustment method or an inertia decrease adjustment method, wherein the inertia adjustment method for the power system is determined in the following manner: if the current inertia belongs to the high inertia interval, the inertia adjustment method is the inertia decrease adjustment method; if the current inertia belongs to the low inertia interval, the inertia adjustment method is the inertia increase adjustment method.

[0010] Optionally, acquiring the current inertia of the power system includes: acquiring the regional inertia of at least one preset area covered by the power system; and taking the sum of the regional inertias corresponding to at least one preset area as the current inertia of the power system.

[0011] Optionally, the power system further includes a busbar, one end of which is connected to the synchronous generator, the distributed energy storage device and the flywheel unit, and the other end of which is connected to one end of the transformer.

[0012] Optionally, the distributed energy storage device includes: a photovoltaic power generation device or a wind power generation device.

[0013] In a second aspect, an embodiment of the present application further provides an inertia regulation method for an electric power system, wherein the electric power system comprises a synchronous generator, an energy storage device, a flywheel unit and a transformer, wherein the synchronous generator, the energy storage device and the flywheel unit are all connected to one end of the transformer, and the other end of the transformer is connected to a power grid, and the transformer is used to regulate the voltage flowing into the power grid, wherein the method comprises: obtaining the current inertia of the electric power system; determining an inertia regulation mode for the electric power system according to the current inertia according to the inertia regulation strategy, wherein the inertia regulation mode is used to indicate that the inertia of the electric power system is changed by at least one inertia device of the electric power system, and the inertia device comprises the synchronous generator and the flywheel unit; and executing the inertia regulation mode to balance the inertia of the electric power system.

[0014] In a third aspect, an embodiment of the present application further provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the steps of the inertia regulation method of the power system as described in the first aspect or any possible implementation manner of the first aspect are executed.

[0015] An embodiment of the present application provides an electric power system and an inertia regulation method thereof, wherein the electric power system includes a synchronous generator, a distributed energy storage device, a flywheel unit, a transformer and a controller, wherein the synchronous generator, the distributed energy storage device and the flywheel unit are all connected to one end of the transformer, and the other end of the transformer is connected to a power grid, and the transformer is used to regulate the voltage flowing into the power grid, and the controller is connected to the synchronous generator and the flywheel unit, wherein the controller is configured to: obtain the current inertia of the electric power system; determine the inertia regulation method for the electric power system according to the current inertia according to the inertia regulation strategy, and the inertia regulation method is used to indicate that the inertia of the electric power system is changed by at least one inertial device of the electric power system, and the inertial device includes the synchronous generator and the flywheel unit; and execute the inertia regulation method to balance the inertia of the electric power system. By adding a flywheel unit to the inertia device of the power system and monitoring the current inertia of the power system, the inertia adjustment method corresponding to the current inertia is determined according to the inertia adjustment strategy, so that the inertia of the power system is adjusted by the inertia device in the power system, the technical problem of poor stability of the energy storage system caused by unstable inertia in the prior art is solved, and the technical effect of improving the stability of the energy storage system is achieved.

[0016] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, preferred embodiments are specifically cited below and described in detail with reference to the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0018] Figure 1 A schematic diagram of the structure of a power system provided in an embodiment of the present application is shown.

[0019] Figure 2 A flow chart of an inertia regulation method for an electric power system provided in an embodiment of the present application is shown.

[0020] Figure 3 A functional module diagram of an inertia regulating device for an electric power system provided in an embodiment of the present application is shown. DETAILED DESCRIPTION

[0021] To make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the technical scheme in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. It should be understood that the drawings in the present application only serve the purpose of explanation and description and are not used to limit the scope of protection of the present application. In addition, it should be understood that the schematic drawings are not drawn in real proportion. The flowchart used in this application shows the operations implemented according to some embodiments of the present application. It should be understood that the operations of the flowchart can be implemented out of sequence, and the steps without logical context can be reversed in order or implemented simultaneously. In addition, those skilled in the art, under the guidance of the content of the present application, can add one or more other operations to the flowchart, or remove one or more operations from the flowchart.

[0022] In addition, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. The components of the embodiments of the present application described and shown in the drawings here can be arranged and designed in various configurations. Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the application claimed for protection, but merely represents the selected embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without making creative work belong to the scope of protection of the present application.

[0023] In the prior art, the proportion of renewable energy generation in the power system has gradually increased, resulting in a smaller inertia of the power system. In addition, during the startup process of the generator set of the power system to supply power to the power grid, it takes a certain amount of time for the generator set to output a large amount of power, which also leads to a smaller inertia of the power system. The smaller the inertia of the power system, the smaller the frequency adjustment range of the power system. Furthermore, when the system needs to adjust the frequency significantly to maintain system stability, the smaller frequency adjustment range cannot perform a larger frequency adjustment, affecting the stability of the system.

[0024] Based on this, the embodiment of the present application provides a power system and an inertia regulation method thereof, by adding a flywheel unit to the inertia device of the power system, and by monitoring the current inertia of the power system, the inertia regulation method corresponding to the current inertia is determined according to the inertia regulation strategy, so that the inertia of the power system is regulated by the inertia device in the power system, and the technical problem of poor stability of the energy storage system caused by unstable inertia in the prior art is solved, and the technical effect of improving the stability of the energy storage system is achieved, which is specifically as follows:

[0025] See also Figure 1 , Figure 1 This is a schematic diagram of the structure of a power system provided in an embodiment of the present application. Figure 1 As shown, the power system provided in the embodiment of the present application includes a synchronous generator SG, a distributed energy storage device DG, a flywheel unit F, a transformer T and a controller MCU, the synchronous generator, the distributed energy storage device and the flywheel unit are all connected to one end of the transformer, the other end of the transformer is connected to the power grid, the transformer is used to adjust the voltage flowing into the power grid, and the controller is connected to the synchronous generator and the flywheel unit.

[0026] The power system further comprises a busbar BUS, one end of which is connected to the synchronous generator, the distributed energy storage device and the flywheel unit, and the other end of which is connected to one end of the transformer.

[0027] That is to say, when the distributed energy storage device, synchronous generator and flywheel unit are in working state, they all output the same AC power to the bus, and the AC power on the bus is converted into the AC power required by the power grid through the transformer, thereby supplying power to the power grid.

[0028] Specifically, the distributed energy storage device includes: a photovoltaic power generation device or a wind power generation device. That is to say, the photovoltaic power generation device includes a photovoltaic panel and a DC-AC converter, which converts the DC power generated by the photovoltaic panel into AC power through the DC-AC converter, and controls the AC power to meet the AC power conditions for being connected to the bus; the wind power generation device includes a wind turbine and an AC-AC converter, which inputs the AC power generated by the wind turbine into the AC-AC converter, and adjusts the AC power to meet the AC power conditions for being connected to the bus through the AC-AC converter, thereby realizing the power transmission between the AC power output by the distributed energy storage device and the bus.

[0029] Among them, the AC power generated when the synchronous generator is in working state and the flywheel unit is in working state should also meet the conditions for being connected to the busbar, so that the AC power on the busbar tends to be stable, and then the AC power on the busbar is regulated through the transformer, so that the AC power output by the transformer can be connected to the power grid to realize power supply to the power grid.

[0030] The controller is connected to the synchronous generator and the flywheel unit respectively, and the inertia regulation of the power system is achieved by controlling the synchronous generator and the flywheel unit.

[0031] Among them, since the power system includes distributed energy storage devices that need to perform virtual synchronous motor control, the voltage output by the distributed energy storage device is controlled by obtaining the voltage on the grid side and the voltage transmitted by the distributed energy storage device to the bus, so as to better achieve grid connection. Stable operation is achieved according to the control method of the virtual synchronous motor and the energy storage converter. The power system simply models the synchronous generator as the current I detected by the sensor ac , Induction voltage E f , Synchronous impedance Z s =r+jx to output voltage to the outside, where r is resistance and x is reactance. The output voltage of this model is The power system can perform voltage control through the output voltage.

[0032] See also Figure 2 , Figure 2 The flowchart of an inertia adjustment method for a power system provided in an embodiment of the present application is shown in FIG. The inertia adjustment method is applied in a controller, such as Figure 2 As shown, the inertia adjustment method includes the following steps:

[0033] S101: Acquire the current inertia of the power system.

[0034] Wherein, obtaining the current inertia of the power system includes: obtaining the regional inertia of at least one preset area covered by the power system; and taking the sum of the regional inertias corresponding to at least one preset area as the current inertia of the power system.

[0035] That is, according to the target area covered by the power system, the target area includes at least one preset area, and the current inertia corresponding to the target area covered by the power system is calculated by calculating the regional inertia of each preset area and then summing the regional inertias.

[0036] The target area covered by the power system and at least one preset area within the target area are pre-divided.

[0037] Exemplarily, the current inertia of the power system is calculated by the following formula:

[0038]

[0039] In formula (1), M refers to the current inertia of the power system, A i refers to the current phase of the i-th preset area, ω0 refers to the initial phase, refers to the sum of the current phases of all preset areas within the target area, I refers to the number of all preset areas within the target area, and K i Refers to the ratio of the power flow to the phase difference in the i-th preset area. T i Refers to the flow of the i-th preset area.

[0040] Exemplarily, the preset areas are sorted according to the order of power transmission to obtain preset area 1, ..., preset area i, ..., preset area I, and for each preset area, the current phase A of the preset area is calculated. i The current phase A of the previous preset area of ​​the preset area i-1 The phase difference of the preset area's power flow T i The ratio of the phase difference is taken as the K of the preset area. i The phase difference of the preset area 1 can be calculated by the difference between the current phase of the preset area 1 and the current phase of the preset area I.

[0041] Exemplarily, the power system detects the initial phase, current phase and power flow of each preset area through a phase measurement unit (PMU) to calculate the inertia of each preset area, and uses the sum of the inertias of all preset areas as the current inertia corresponding to the target area covered by the power system.

[0042] S102: According to the inertia adjustment strategy, determine the inertia adjustment method for the power system through the current inertia.

[0043] The inertia adjustment mode is used to indicate that the inertia of the power system is changed by at least one inertial device of the power system, and the inertial device includes the synchronous generator and the flywheel unit.

[0044] That is to say, since both the flywheel unit and the synchronous generator are inertial devices, they will affect the inertia of the power system. Then, the inertia of the power system can be changed by controlling the inertial devices of the power system.

[0045] Specifically, the inertia adjustment strategy includes: determining whether the current inertia belongs to a preset inertia interval; if the current inertia belongs to the preset inertia interval, not performing inertia adjustment on the power system; if the current inertia does not belong to the preset inertia interval, determining the inertia adjustment method for the power system based on the target inertia interval to which the current inertia belongs.

[0046] That is to say, when the current inertia belongs to the preset inertia interval, it is considered that the inertia of the power system at this time is in a normal state and no inertia adjustment is required. When the current inertia does not belong to the preset inertia interval, it is considered that the inertia of the power system at this time is in an abnormal state, and the abnormal state includes a high inertia state or a low inertia state.

[0047] The target inertia interval includes a high inertia interval greater than an upper limit value of the preset inertia interval or a low inertia interval less than a lower limit value of the preset inertia interval, and the inertia adjustment mode includes an inertia increase adjustment mode or an inertia decrease adjustment mode, wherein the inertia adjustment mode for the power system is determined in the following manner: if the current inertia belongs to the high inertia interval, the inertia adjustment mode is the inertia decrease adjustment mode; if the current inertia belongs to the low inertia interval, the inertia adjustment mode is the inertia increase adjustment mode.

[0048] That is to say, the inertia adjustment method for the power system is determined by the positional relationship between the current inertia and the preset inertia interval. When the current inertia belongs to the preset inertia interval, no inertia adjustment is required. When the current inertia is greater than the upper limit of the preset inertia interval, it is considered that the inertia of the power system at this time is in a high inertia state, and the inertia of the power system needs to be reduced. Then, the inertia adjustment method determined at this time is the inertia reduction adjustment method. When the current inertia is less than the lower limit of the preset inertia interval, it is considered that the inertia of the power system at this time is in a low inertia state, and the inertia of the power system needs to be increased. Then, the inertia adjustment method determined at this time is the inertia increase adjustment method.

[0049] Specifically, the inertia adjustment method is used to indicate changing the mechanical power of the power system by controlling at least one inertial device of the power system to change the inertia of the power system, wherein the inertia adjustment method includes: an inertia increase adjustment method for increasing the inertia by increasing the mechanical power of the power system, or an inertia decrease adjustment method for reducing the inertia by reducing the mechanical power of the power system.

[0050] That is to say, the mechanical power of the power system is adjusted by controlling the inertial device to increase or decrease the mechanical power, thereby increasing or decreasing the inertia of the power system.

[0051] Specifically, the relationship between the mechanical power and the current inertia of the system is determined based on the swing equation. The swing equation includes:

[0052]

[0053] In formula (2), M refers to the current inertia of the power system, Refers to the acceleration of simulating the power system as a synchronous generator, P m Refers to the mechanical power of simulating the power system as a synchronous generator, P e Refers to the simulation of the power system as the electromagnetic power of a synchronous generator.

[0054] In other words, formula (2) shows that when the acceleration of the synchronous generator simulated by the power system is positive, the relationship between the mechanical power of the power system and the current inertia is positively correlated. That is, when the synchronous generator simulated by the power system is accelerating, the greater the mechanical power, the greater the inertia of the power system, and the smaller the mechanical power, the smaller the inertia of the power system. When the acceleration of the synchronous generator simulated by the power system is negative, the power system needs to implement system power regulation and other operations through the control system of the virtual synchronous motor VSG, and at the same time, participate in the real-time balance of the power grid and system inertia according to the F-VSG to achieve the automatic speed regulation function.

[0055] For example, when the acceleration of the power system simulated as a synchronous generator in formula (2) is positive, it means that the distributed energy storage device, synchronous generator and flywheel unit on the power system are combined to supply power to the power grid. That is to say, even if the flywheel unit is in the energy storage stage or the cut-out stage, the distributed energy storage device, synchronous generator and flywheel unit in the power system are in an accelerated state to supply power to the power grid as a simulated synchronous generator. Therefore, the mechanical power at this time is positively correlated with the inertia of the power system. When the distributed energy storage device is charged through the power grid, the synchronous generator is converted into an electric motor to consume electrical energy, and the flywheel unit absorbs the power of the power grid, the acceleration of the synchronous generator simulated by the power system is negative, which is equivalent to the power consumption of the electrical equipment. At this time, the inertia of the power system cannot be adjusted.

[0056] That is, when the power system is simulated as a synchronous generator with positive acceleration, the inertia of the system is increased by increasing the mechanical power, and the inertia of the system is reduced by reducing the mechanical power.

[0057] S103: Execute the inertia adjustment method to balance the inertia of the power system.

[0058] The synchronous generators include multiple ones, and the mechanical power of the power system is changed in the following manner: obtaining the current status of the flywheel unit and multiple synchronous generators of the power system, wherein the current status includes a working state and a non-working state, and adjusting the flywheel unit in the non-working state to the working state and / or adjusting the synchronous generator in the non-working state to the working state to increase the mechanical power of the power system; adjusting the flywheel unit in the working state to the non-working state and / or adjusting the synchronous generator in the working state to the non-working state to reduce the mechanical power of the power system.

[0059] That is to say, when the inertia adjustment mode is determined to be the inertia increase adjustment mode, the flywheel unit in the non-working state can be adjusted to the working state and / or the synchronous generator in the non-working state can be adjusted to the working state to increase the mechanical power, thereby increasing the inertia of the power system. That is, by connecting the flywheel unit and / or the synchronous generator cut out of the power system to the power system, the mechanical power of the power system can be increased. When the inertia adjustment mode is determined to be the inertia reduction adjustment mode, the flywheel unit in the working state can be adjusted to the non-working state and / or the synchronous generator in the working state can be adjusted to the non-working state to reduce the mechanical power, thereby reducing the inertia of the power system. That is, by cutting the flywheel unit and / or the synchronous generator connected to the power system out of the power system, the mechanical power of the power system can be reduced.

[0060] That is to say, the inertia of the power system is changed by changing the number of inertial devices connected to the power system, that is, the inertia of the power system is increased by increasing the inertial devices connected to the power system, and the inertia of the power system is reduced by reducing the inertial devices connected to the power system. In addition, in order to ensure the stability of the power supply of the power system, even if the synchronous generator of the power system is cut out, it is necessary to ensure that the synchronous generator and distributed energy storage device connected to the power system can meet the power required by the power grid. Therefore, the number of synchronous generators is multiple, and it is necessary to continuously control the proportion of the output power corresponding to the synchronous generator and distributed energy storage device connected to the power system to meet the preset proportion requirements, so as to balance the synchronous generator and green energy generation.

[0061] Existing products must switch control modes when the system is interlocked or running independently. Therefore, the device must be stopped once when connected in parallel or disconnected with the power system. The flywheel needs an initialization working mode in the early stage, which is to detect the position signal in the flywheel rotor, and each boundary sensor is qualified, and the vacuum value in the flywheel is qualified. After there are no abnormalities in the auxiliary equipment, it starts to increase the speed from 0RPM (revolutions per minute) to the basic working speed such as 3000RPM. The speed at this stage is called the beginning of the energy storage stage. At this time, the bidirectional power electronics switches to VF mode. There are changes in the switching process and it cannot be continuous. In addition, the system's PCS energy storage converter also needs to compensate and control the system based on the voltage, frequency, power and other parameters collected in real time on the grid side, and control the power output by the bus by changing the current and / or phase angle, so as to better meet the needs of the grid.

[0062] Based on the same application concept, an inertia adjustment device corresponding to the inertia adjustment method of the power system provided in the above embodiment is also provided in the embodiment of the present application. Since the principle of solving the problem by the device in the embodiment of the present application is similar to the inertia adjustment method in the above embodiment of the present application, the implementation of the device can refer to the implementation of the method, and the repeated parts will not be repeated.

[0063] like Figure 3 As shown, Figure 3 A functional module diagram of an inertia regulating device for an electric power system provided in an embodiment of the present application. The inertia regulating device 10 for an electric power system comprises: an acquisition module 101, which acquires the current inertia of the electric power system; a determination module 102, which determines the inertia regulating mode for the electric power system through the current inertia according to the inertia regulating strategy, wherein the inertia regulating mode is used to indicate that the inertia of the electric power system is changed through at least one inertia device of the electric power system, wherein the inertia device comprises the synchronous generator and the flywheel unit; and an adjustment module 103, which executes the inertia regulating mode to balance the inertia of the electric power system.

[0064] Based on the same application concept, an embodiment of the present application further provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the steps of the inertia regulation method of the power system provided in the above embodiment are executed.

[0065] Specifically, the storage medium can be a general storage medium, such as a mobile disk, a hard disk, etc. When the computer program on the storage medium is run, the above-mentioned inertia adjustment method of the power system can be executed, by adding a flywheel unit to the inertia device of the power system, and by monitoring the current inertia of the power system, the inertia adjustment method corresponding to the current inertia is determined according to the inertia adjustment strategy, so that the inertia of the power system is adjusted by the inertia device in the power system, which solves the technical problem of poor stability of the energy storage system caused by inertia instability in the prior art, and achieves the technical effect of improving the stability of the energy storage system.

[0066] Those skilled in the art can clearly understand that, for the convenience and simplicity of description, the specific working process of the system and device described above can refer to the corresponding process in the aforementioned method embodiment, and will not be repeated here. In the several embodiments provided in the present application, it should be understood that the disclosed system, device and method can be implemented in other ways. The device embodiments described above are merely schematic. For example, the division of the units is only a logical function division. There may be other division methods in actual implementation. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some communication interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0067] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0068] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit.

[0069] If the function is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a non-volatile computer-readable storage medium that is executable by a processor. Based on this understanding, the technical solution of the present application, or the part that contributes to the prior art or the part of the technical solution, can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including a number of instructions to enable a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM), random access memory (RAM), disk or optical disk, etc., various media that can store program codes.

[0070] The above are only specific implementations of the present application, but the protection scope of the present application is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. A power system, characterized in that: The power system includes a synchronous generator, a distributed energy storage device, a flywheel unit, a transformer and a controller. The synchronous generator, the distributed energy storage device and the flywheel unit are all connected to one end of the transformer, and the other end of the transformer is connected to the power grid. The transformer is used to adjust the voltage flowing into the power grid. The controller is connected to the synchronous generator and the flywheel unit. Wherein, the controller is configured as follows: obtaining a current inertia of the power system; According to the inertia adjustment strategy, an inertia adjustment mode for the power system is determined by the current inertia, wherein the inertia adjustment mode is used to indicate that the inertia of the power system is changed by at least one inertial device of the power system, wherein the inertial device includes the synchronous generator and the flywheel unit; The inertia adjustment method is executed to balance the inertia of the power system.

2. The power system according to claim 1, characterized in that: The inertia adjustment mode is used to indicate that the mechanical power of the power system is changed by controlling at least one inertial device of the power system to change the inertia of the power system. The inertia adjustment method includes: an inertia increase adjustment method for increasing the inertia by increasing the mechanical power of the power system, or an inertia decrease adjustment method for decreasing the inertia by decreasing the mechanical power of the power system.

3. The power system according to claim 2, characterized in that: The synchronous generator includes a plurality of synchronous generators, and the mechanical power of the power system is changed in the following manner: acquiring the current states of the flywheel unit and the plurality of synchronous generators of the power system, wherein the current states include a working state and a non-working state, Adjusting the flywheel unit in the non-working state to the working state and / or adjusting the synchronous generator in the non-working state to the working state to increase the mechanical power of the power system; The flywheel unit in the working state is adjusted to the non-working state and / or the synchronous generator in the working state is adjusted to the non-working state to reduce the mechanical power of the power system.

4. The power system according to claim 1, characterized in that: The inertia adjustment strategy includes: determining whether the current inertia belongs to a preset inertia interval; if the current inertia belongs to the preset inertia interval, not performing inertia adjustment on the power system; if the current inertia does not belong to the preset inertia interval, determining the inertia adjustment method for the power system according to the target inertia interval to which the current inertia belongs.

5. The power system according to claim 4, characterized in that: The target inertia interval includes a high inertia interval greater than an upper limit of the preset inertia interval or a low inertia interval less than a lower limit of the preset inertia interval, and the inertia adjustment mode includes an inertia increase adjustment mode or an inertia decrease adjustment mode. The inertia adjustment method for the power system is determined in the following manner: If the current inertia belongs to the high inertia interval, the inertia adjustment mode is an inertia reduction adjustment mode; If the current inertia belongs to the low inertia interval, the inertia adjustment mode is an inertia increase adjustment mode.

6. The power system according to claim 1, characterized in that: The obtaining of the current inertia of the power system comprises: Acquiring regional inertia of at least one preset area covered by the power system; The sum of the regional inertias corresponding to at least one preset region is used as the current inertia of the power system.

7. The power system according to claim 1, characterized in that: The power system further comprises a busbar, one end of which is connected to the synchronous generator, the distributed energy storage device and the flywheel unit, and the other end of which is connected to one end of the transformer.

8. The power system according to any one of claims 1 to 7, characterized in that: The distributed energy storage device includes a photovoltaic power generation device or a wind power generation device.

9. A method for regulating inertia of an electric power system, characterized in that: The power system includes a synchronous generator, an energy storage device, a flywheel unit and a transformer. The synchronous generator, the energy storage device and the flywheel unit are all connected to one end of the transformer, and the other end of the transformer is connected to the power grid. The transformer is used to adjust the voltage flowing into the power grid. Wherein, the method comprises: obtaining a current inertia of the power system; According to the inertia adjustment strategy, an inertia adjustment mode for the power system is determined by the current inertia, wherein the inertia adjustment mode is used to indicate that the inertia of the power system is changed by at least one inertial device of the power system, wherein the inertial device includes the synchronous generator and the flywheel unit; The inertia adjustment method is executed to balance the inertia of the power system.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the steps of the inertia regulation method of the power system as claimed in claim 9 are executed.

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