Virtual synchronization power prediction multi-layer coordination control method, system, device and medium

Abstract

The invention relates to the technical field of power system control, and discloses a virtual synchronous power prediction multi-layer coordination control method, system and device and a medium, and the method comprises the steps: setting a virtual synchronous generator control layer at the AC side of each voltage source converter, and simulating the mechanical dynamic characteristics of a synchronous machine to generate a voltage reference; a DC voltage-power cooperative control layer is arranged on a common DC bus side, and active power reference is adjusted based on a droop mechanism; an indirect feed-forward coordination control layer is arranged on the upper layer, a prediction deviation is calculated by using a port power prediction value, and feed-forward correction is performed on an active power reference and a bus voltage reference. Control instructions are transmitted among the layers in a cascading mode, and a closed-loop coordination mechanism is formed. The corresponding device comprises a local control unit and an upper-layer coordination control unit, and stable operation and quick response of the multi-end system under power fluctuation are achieved.

Description

Technical Field

[0001] This invention relates to the field of power system control technology, and in particular to a virtual synchronous power prediction multi-layer coordinated control method, system, equipment and medium. Background Technology

[0002] With the large-scale integration of distributed energy sources (such as photovoltaics and energy storage) and the increasing DC load on buildings, the power grid has placed higher demands on the flexibility, stability, and economy of power transmission. Multi-terminal VSC flexible DC systems, due to their advantages such as flexible control and rapid power regulation, have become the core technology for distributed energy consumption and DC load power supply in the power grid.

[0003] However, existing multi-terminal VSC flexible DC system control technologies have several shortcomings. First, traditional VSC converters are static devices composed of power electronic components, lacking the inertia and damping characteristics of traditional synchronous generators. This makes them prone to frequency and voltage fluctuations during load fluctuations, affecting power supply stability. Second, existing DC bus voltage control often employs a single droop control strategy, failing to consider dynamic voltage changes on the DC side, resulting in uneven power distribution across multiple terminals and limited voltage support capacity. Third, control strategies are mostly "passive response" modes, relying solely on real-time operating data for feedback adjustments. This lack of predictive capability for load fluctuations leads to delayed responses and increases the risk of transient system impacts. Finally, the control hierarchy is fragmented, lacking effective linkage between local control and global coordination, making it difficult to balance rapid local response with global optimization goals. Summary of the Invention

[0004] In view of the aforementioned existing problems, the present invention is proposed.

[0005] Therefore, this invention provides a virtual synchronous power prediction multi-layer coordinated control method, system, device and medium, which can solve the problems of system stability and dynamic response speed caused by the lack of inertia and damping characteristics and the single DC voltage control strategy in existing multi-terminal VSC flexible DC systems.

[0006] To solve the above-mentioned technical problems, the present invention provides the following technical solution: In a first aspect, the present invention provides a virtual synchronous power prediction multi-layer coordinated control method, comprising: A virtual synchronous generator control layer is established on the AC side of each voltage source converter, and AC voltage amplitude reference and phase angle reference are generated through virtual mechanical equations and virtual rotor angle equations. A DC voltage-power collaborative control layer is established on the side of the common DC bus. The active power reference of each voltage source converter is correlated with the deviation between the corresponding DC side voltage and the common DC bus voltage reference value to generate an active power reference with droop adjustment. An indirect feedforward coordination control layer based on power prediction is established above the DC voltage-power coordinated control layer. The predicted power deviation is calculated using the power prediction values ​​of each port, and the active power reference and common DC bus voltage reference values ​​of each voltage source converter are corrected through the feedforward channel. The active power reference and common DC bus voltage reference values, corrected by the indirect feedforward coordination control layer, are input to the DC voltage-power collaborative control layer. The active power reference output by the DC voltage-power collaborative control layer is then input to the virtual synchronous generator control layer, which outputs the dq axis voltage reference value, thus completing the multi-layer coordination control process.

[0007] As a preferred embodiment of the virtual synchronous power prediction multi-layer coordinated control method of the present invention, wherein: establishing a virtual synchronous generator control layer on the AC side of each voltage source converter includes: The change in virtual angular velocity is calculated based on the virtual moment of inertia, virtual damping coefficient, grid synchronization angular velocity, current virtual angular velocity, virtual mechanical input power, and actual active power output. The virtual rotor phase angle is obtained by integrating the difference between the virtual angular velocity change and the grid synchronous angular velocity. An AC voltage amplitude reference and a phase angle reference are generated based on the virtual angular velocity and the virtual rotor phase angle.

[0008] As a preferred embodiment of the virtual synchronous power prediction multi-layer coordinated control method described in this invention, the virtual mechanical input power is obtained by superimposing the planned active power issued by the upper-level dispatcher with the frequency deviation proportional adjustment amount, and the frequency deviation proportional adjustment amount is determined by multiplying the difference between the grid synchronous angular velocity and the current virtual angular velocity by a preset proportional coefficient.

[0009] As a preferred embodiment of the virtual synchronous power prediction multi-layer coordinated control method described in this invention, the step of establishing a DC voltage-power coordinated control layer on the common DC bus side includes: Obtain the planned active power of each voltage source converter issued by the superior dispatcher; Obtain the actual voltage values ​​on the DC side of each voltage source converter and the voltage reference value of the common DC bus; The droop adjustment amount is obtained by multiplying the DC voltage droop coefficient of each voltage source converter with the deviation between the corresponding actual DC side voltage value and the reference value of the common DC bus voltage. The corresponding droop adjustment is subtracted from the planned active power of each voltage source converter to generate a droop-adjusted active power reference.

[0010] As a preferred embodiment of the virtual synchronous power prediction multi-layer coordinated control method described in this invention, the establishment of a DC voltage-power coordinated control layer on the common DC bus side further includes: Based on the charging and discharging dynamic characteristics of the equivalent capacitance on the DC side of each voltage source converter, the difference between the DC current flowing into the voltage source converter and the DC current flowing out of the voltage source converter is taken as the capacitance current. The state of the DC side voltage of the voltage source converter is updated based on the capacitor current.

[0011] As a preferred embodiment of the virtual synchronous power prediction multi-layer coordinated control method of the present invention, wherein: establishing an indirect feedforward coordinated control layer based on power prediction above the DC voltage-power coordinated control layer includes: Based on historical operating data and real-time measurement data, predict the active power value of each voltage source converter port at a future set time point; The predicted active power value of each port is compared with the actual active power output of the corresponding voltage source converter at the current moment to obtain the predicted power deviation. Each predicted power deviation is multiplied by its corresponding feedforward gain coefficient and then superimposed onto the droop-adjusted active power reference to generate a feedforward-corrected active power reference.

[0012] As a preferred embodiment of the virtual synchronous power prediction multi-layer coordinated control method of the present invention, wherein: establishing an indirect feedforward coordinated control layer based on power prediction above the DC voltage-power coordinated control layer further includes: The predicted power deviations at all voltage source converter ports are summed to obtain the total predicted power deviation for the entire network. Multiply the sum of the predicted power deviations of the entire network by a preset DC voltage reference correction coefficient to obtain the voltage reference adjustment amount; The voltage reference adjustment is superimposed on the base voltage reference value of the common DC bus to generate the corrected common DC bus voltage reference value.

[0013] Secondly, the present invention provides a virtual synchronous power prediction multi-layer coordination control system, comprising: The local control unit, located in each voltage source converter, is used to run the virtual synchronous generator control layer, receive active power reference and AC voltage reference, and generate dq axis voltage reference values ​​through virtual mechanical equations and virtual rotor angle equations. The upper-level coordination and control unit is located on the common DC bus side and includes a DC voltage-power coordinated control module and an indirect feedforward coordinated control module; The DC voltage-power coordinated control module is used to receive the planned active power of each voltage source converter, the actual DC side voltage value, and the reference value of the common DC bus voltage, and generate a corrected active power reference through droop adjustment. The indirect feedforward coordination control module is used to predict the future active power of each port based on historical operating data and real-time measurement data, calculate the predicted power deviation, and generate a feedforward corrected active power reference and a corrected common DC bus voltage reference value. The upper-level coordination control unit transmits the feedforward-corrected active power reference and the corrected common DC bus voltage reference value to each local control unit, forming a three-level cascaded control architecture.

[0014] Thirdly, the present invention provides an electronic device including a memory and a processor, wherein the memory stores a computer program, and the processor executes the computer program to implement the steps of the method described above.

[0015] Fourthly, the present invention provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of the method described above.

[0016] Compared with existing technologies, the beneficial effect of this invention is that it proposes a virtual synchronous power prediction multi-layer coordinated control method. This method constructs a three-layer control architecture: a virtual synchronous generator control layer is set up on the AC side of each voltage source converter to simulate the mechanical dynamic characteristics of a synchronous machine and generate a voltage reference; a DC voltage-power collaborative control layer is set up on the common DC bus side to adjust the active power reference based on a droop mechanism; and an indirect feedforward coordinated control layer is set up at the upper layer to calculate the prediction deviation using port power prediction values ​​and to perform feedforward correction on the active power reference and bus voltage reference. Control commands are cascaded between the layers to form a closed-loop coordination mechanism. The corresponding devices include a local control unit and an upper-layer coordinated control unit, enabling stable operation and rapid response of the multi-terminal system under power fluctuations. Attached Figure Description

[0017] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the following description of the embodiments will be briefly introduced. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 The present invention provides a flowchart of a virtual synchronous power prediction multi-layer coordinated control method according to an embodiment of the present invention.

[0019] Figure 2This is a schematic diagram of a typical three-terminal flexible DC transmission system structure, which is a virtual synchronous power prediction multi-layer coordinated control method provided in an embodiment of the present invention.

[0020] Figure 3 This is a functional block diagram of the single-ended VSC virtual synchronous machine control layer of a multi-layer coordinated control method for virtual synchronous power prediction provided in an embodiment of the present invention.

[0021] Figure 4 This is a block diagram of a multi-terminal VSC DC voltage-power coordinated control method for a virtual synchronous power prediction multi-layer coordinated control method provided in one embodiment of the present invention.

[0022] Figure 5 The present invention provides a power prediction and indirect feedforward coordination control logic block diagram of a virtual synchronous power prediction multilayer coordination control method according to an embodiment of the present invention.

[0023] Figure 6 This is a schematic diagram of the overall architecture of a multi-layer coordinated control method for virtual synchronous power prediction provided in one embodiment of the present invention.

[0024] Figure 7 This is a schematic diagram of the equivalent dynamic model of the DC side of a single-ended VSC for a virtual synchronous power prediction multilayer coordinated control method provided in an embodiment of the present invention.

[0025] Figure 8 This is a schematic diagram of the multi-terminal active power distribution and DC voltage droop characteristics of a virtual synchronous power prediction multi-layer coordinated control method provided in an embodiment of the present invention.

[0026] Figure 9 This is a functional block diagram of a multi-terminal VSC flexible DC system control device for a virtual synchronous power prediction multi-layer coordinated control method provided in one embodiment of the present invention.

[0027] Figure 10 This is an internal structure diagram of an electronic device for a virtual synchronous power prediction multilayer coordinated control method provided in one embodiment of the present invention. Detailed Implementation

[0028] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the protection scope of the present invention.

[0029] It should be noted in advance that the system mentioned in the embodiments as the subject of real-time operation refers to any system configured with this method.

[0030] Example 1, referring to Figure 1 This is the first embodiment of the present invention, which provides a virtual synchronous power prediction multi-layer coordinated control method, including: This invention provides a method that can effectively solve the problems mentioned above. The following will describe in detail how to implement this virtual synchronous power prediction multi-layer coordination control method with reference to several embodiments. Figure 1 A flowchart of a virtual synchronous power prediction multi-layer coordinated control method is shown, including: S101, a virtual synchronous generator control layer is established on the AC side of each voltage source converter, and AC voltage amplitude reference and phase angle reference are generated through virtual mechanical equations and virtual rotor angle equations; In an embodiment of the present invention, a virtual synchronous generator control layer is established on the AC side of each voltage source converter, including: The change in virtual angular velocity is calculated based on the virtual moment of inertia, virtual damping coefficient, grid synchronization angular velocity, current virtual angular velocity, virtual mechanical input power, and actual active power output. The virtual rotor phase angle is obtained by integrating the difference between the virtual angular velocity change and the grid synchronous angular velocity. An AC voltage amplitude reference and a phase angle reference are generated based on the virtual angular velocity and the virtual rotor phase angle.

[0031] It should be noted that if the AC voltage phase angle reference is directly generated based solely on the instantaneous difference between the current virtual angular velocity and the grid synchronous angular velocity, without introducing virtual moment of inertia and virtual damping coefficient to model the dynamic process, the inertial response characteristics of the synchronous generator under disturbance cannot be reproduced. That is, when the source load power changes abruptly, the system frequency will fluctuate violently due to the lack of kinetic energy buffer.

[0032] If the fixed phase angle reference generation method in the traditional vector control strategy is still used at this time, it may cause the converter output power to lose its natural coupling relationship with the grid frequency, weakening the system's ability to suppress frequency disturbances.

[0033] For example, in a scenario where photovoltaic output drops sharply due to cloud cover, if the change in virtual angular velocity is not calculated using virtual mechanical equations, but instead the grid synchronous angular velocity is used directly as the phase angle generation reference, the converter will be unable to release the energy stored in the DC-side capacitor to support active power output, causing the common DC bus voltage to drop rapidly and triggering a chain reaction of grid disconnection.

[0034] For example, in the case of a sudden increase in load, if the rate of change of angular velocity is not constrained by integration based on the virtual moment of inertia, and the voltage phase is immediately adjusted to match the new power demand, the system rate of change of frequency (RoCoF) will exceed the protection setting, triggering the frequency emergency control action and causing unnecessary power outage.

[0035] In such cases, if the converter control layer continues to use a fast response mechanism without inertia, it will not only exacerbate DC voltage oscillations, but also induce power oscillations between multiple terminals due to the lack of damping, seriously threatening the transient stability of the flexible DC system.

[0036] Therefore, this invention establishes a virtual synchronous generator control layer on the AC side of each voltage source converter. First, based on the virtual moment of inertia, virtual damping coefficient, grid synchronization angular velocity, current virtual angular velocity, virtual mechanical input power, and actual active power output, the virtual angular velocity change is calculated by substituting these values ​​into the virtual mechanical equation. Then, the difference between the virtual angular velocity change and the grid synchronization angular velocity is integrated to obtain the virtual rotor phase angle. Finally, the virtual angular velocity and virtual rotor phase angle are combined to generate AC voltage amplitude reference and phase angle reference.

[0037] The aforementioned virtual angular velocity change can be understood as a dynamic variable obtained by simulating the differential equation of motion of a synchronous generator rotor. It is used to characterize the converter's ability to release or absorb kinetic energy under power imbalance conditions, thereby giving the power electronic equipment equivalent rotational inertia and damping characteristics at the control level, and realizing active suppression of frequency and voltage fluctuations.

[0038] In this embodiment of the invention, the virtual mechanical input power is obtained by superimposing the planned active power issued by the upper-level dispatcher with the frequency deviation ratio adjustment amount. The frequency deviation ratio adjustment amount is determined by multiplying the difference between the grid synchronous angular velocity and the current virtual angular velocity by a preset ratio coefficient.

[0039] S102, A DC voltage-power collaborative control layer is established on the common DC bus side, and the deviation between the active power reference of each voltage source converter and the corresponding DC side voltage and common DC bus voltage reference value is correlated to generate an active power reference with droop adjustment. In an embodiment of the present invention, a DC voltage-power coordinated control layer is established on the common DC bus side, including: Obtain the planned active power of each voltage source converter issued by the superior dispatcher; Obtain the actual voltage values ​​on the DC side of each voltage source converter and the voltage reference value of the common DC bus; The droop adjustment amount is obtained by multiplying the DC voltage droop coefficient of each voltage source converter with the deviation between the corresponding actual DC side voltage value and the reference value of the common DC bus voltage. The corresponding droop adjustment is subtracted from the planned active power of each voltage source converter to generate a droop-adjusted active power reference.

[0040] It should be noted that in actual operation, when each voltage source converter in a multi-terminal flexible DC system executes the superior dispatching instructions, if it only mechanically tracks the planned active power without considering the impact of DC side voltage deviation on power distribution, the common DC bus voltage will deviate from the safe operating range. The stability of DC voltage is directly related to the power balance and dynamic response capability of the entire multi-terminal system.

[0041] In embodiments of the present invention, generating a droop-adjusted active power reference may include the following operations: First, it receives the planned active power instructions allocated to each voltage source converter in the current scheduling cycle from the upper-level energy management system. These instructions are issued in the form of discrete time series and contain the target active power output value of each converter.

[0042] Furthermore, the actual voltage values ​​of the DC side of each voltage source converter are collected in real time through the local measurement unit, and the reference value of the common DC bus voltage set by the system-level controller is obtained simultaneously. This reference value represents the DC voltage level that the multi-terminal system expects to maintain.

[0043] Furthermore, the deviation between the DC voltage droop coefficient pre-configured for each voltage source converter and the corresponding actual DC side voltage value and the common DC bus voltage reference value is multiplied to obtain the droop adjustment amount used to compensate for the voltage deviation. This droop adjustment amount reflects the additional active power adjustment share that the converter should undertake according to the local voltage state.

[0044] Furthermore, the corresponding droop adjustment is subtracted from the planned active power of each voltage source converter to generate a droop-adjusted active power reference. This reference value serves as the basis for setting the virtual mechanical input power in the subsequent virtual synchronization control layer.

[0045] It should be noted that the local measurement units mentioned above include, but are not limited to, high-precision Hall voltage sensors, DC voltage sampling modules integrated into converter valve control systems, or fiber-optic isolated voltage transmitters.

[0046] It should also be noted that the planned active power mentioned above can be understood as the basic power command allocated to each voltage source converter by the higher-level dispatcher based on the overall network power balance and economic dispatch objectives. The DC voltage droop coefficient can be understood as the proportional gain parameter used in this invention to characterize the DC voltage regulation capability of a single converter. The droop adjustment amount can be understood as a dynamic correction term used in this invention to achieve automatic power distribution among multiple terminals to maintain DC bus voltage stability. The active power reference after droop adjustment can be understood as the final active power setpoint formed by integrating centralized dispatch commands and local voltage feedback information in this invention, used to drive the mechanical input power input terminal in the virtual synchronous generator model.

[0047] In an embodiment of the present invention, a DC voltage-power coordinated control layer is established on the common DC bus side, and the invention further includes: Based on the charging and discharging dynamic characteristics of the equivalent capacitance on the DC side of each voltage source converter, the difference between the DC current flowing into the voltage source converter and the DC current flowing out of the voltage source converter is taken as the capacitance current. The state of the DC side voltage of the voltage source converter is updated based on the capacitor current.

[0048] It should be noted that in actual operation, the charging and discharging dynamic process of the DC-side equivalent capacitance of the voltage source converter directly affects the instantaneous rate of change of the DC voltage, and accurate updating of the DC voltage state is the fundamental prerequisite for realizing droop control and virtual synchronous response.

[0049] For example, in a scenario where photovoltaic output drops sharply due to cloud cover, if the capacitor charging and discharging effect caused by the imbalance between the DC current flowing into and out of the converter is not considered, the DC voltage will be mistakenly regarded as a static quantity. In this case, it cannot reflect the energy exchange behavior of the DC-side energy storage element on a millisecond time scale, and may even cause the virtual synchronization control layer to receive a distorted voltage feedback signal, thereby leading to misadjustment of active power command and failure of frequency support.

[0050] For example, if a sudden increase in load causes a momentary increase in the converter output current, the DC-side capacitor will inevitably enter a discharge state to compensate for the power shortage. If only the DC voltage value of the previous sampling period is used as the current state without dynamic updates based on the capacitor current, the true trend of the voltage rapidly dropping will be masked, leading to a misjudgment that the system is still in a steady-state operation.

[0051] Therefore, it is necessary to take the difference between the DC current flowing into and out of the voltage source converter as the capacitor current based on the charging and discharging dynamic characteristics of the equivalent capacitor on the DC side of each voltage source converter, and update the state of the DC side voltage of the voltage source converter in real time through the discretized capacitor voltage differential equation based on the capacitor current, thereby providing high-fidelity local voltage dynamic information for droop regulation and virtual inertia control.

[0052] S103, establish an indirect feedforward coordination control layer based on power prediction above the DC voltage-power coordinated control layer, calculate the predicted power deviation using the power prediction value of each port, and correct the active power reference and common DC bus voltage reference value of each voltage source converter through the feedforward channel. In an embodiment of the present invention, an indirect feedforward coordination control layer based on power prediction is established above the DC voltage-power coordinated control layer, including: Based on historical operating data and real-time measurement data, predict the active power value of each voltage source converter port at a future set time point; The predicted active power value of each port is compared with the actual active power output of the corresponding voltage source converter at the current moment to obtain the predicted power deviation. Each predicted power deviation is multiplied by its corresponding feedforward gain coefficient and then superimposed onto the droop-adjusted active power reference to generate a feedforward-corrected active power reference.

[0053] It should be understood that when the output of new energy sources or loads connected to a voltage source converter in a multi-terminal flexible DC system fluctuates rapidly, if only droop regulation and virtual synchronization control are used for passive response, the system frequency and DC voltage will experience unacceptable overshoot or drop in the early stage of the disturbance.

[0054] If future power change trends are completely ignored in the control structure and only the current measured power is used as the feedback basis, the power command may lag behind the actual demand due to control delay, thereby weakening the converter's initiative and foresight in supporting the system's dynamics.

[0055] After detecting that the power fluctuation has obvious predictability characteristics, this invention initiates an indirect feedforward coordinated control mechanism based on power prediction. A feedforward correction channel is established above the DC voltage-power coordinated control layer. Based on historical operating data and real-time measurement data, the active power value of each voltage source converter port at a future set time point is predicted. The predicted active power value of each port is compared with the actual active power output of the corresponding voltage source converter at the current time to obtain the predicted power deviation. Each predicted power deviation is multiplied by the corresponding feedforward gain coefficient and then superimposed on the droop-adjusted active power reference to generate the feedforward-corrected active power reference.

[0056] The aforementioned predicted power deviation can be understood as a quantitative indicator used in this invention to characterize the trend of power supply and demand imbalance within a short-term window. The feedforward gain coefficient can be understood as a proportional parameter used in this invention to adjust the intensity of the active power reference correction based on the predicted deviation; this parameter is tuned according to the converter capacity, response bandwidth, and system damping requirements. The feedforward-corrected active power reference can be understood as an enhanced power command formed in this invention by integrating historical trends, real-time status, and future prediction information, used to guide the virtual synchronization control layer to adjust the mechanical input power in advance, thereby suppressing initial frequency and voltage deviations.

[0057] In an embodiment of the present invention, an indirect feedforward coordination control layer based on power prediction is established above the DC voltage-power coordinated control layer, and the invention further includes: The predicted power deviations at all voltage source converter ports are summed to obtain the total predicted power deviation for the entire network. Multiply the sum of the predicted power deviations of the entire network by the preset DC voltage reference correction coefficient to obtain the voltage reference adjustment amount; The voltage reference adjustment is superimposed on the base voltage reference value of the common DC bus to generate the corrected common DC bus voltage reference value.

[0058] It is worth noting that the new energy sources or loads connected to each voltage source converter in a multi-terminal flexible DC system have strong randomness and volatility. Such local power disturbances can propagate to the entire network through DC bus coupling, thereby affecting the overall DC voltage stability.

[0059] When a photovoltaic power station experiences a sudden drop in power output due to rapid cloud movement, the corresponding converter port will show a significant negative predicted power deviation. If multiple such deviations are superimposed over time, they will cause a continuous drop in the common DC bus voltage, and may even trigger the low voltage protection action, causing some converters to disconnect from the grid.

[0060] Conversely, if multiple wind farms simultaneously experience a sudden increase in wind speed, and each port shows a concentrated release of positive predicted power deviation, the excess energy on the DC side will push up the bus voltage. If not coordinated and controlled, it may exceed the withstand voltage limit of the DC capacitor, threatening equipment safety.

[0061] If each converter independently performs local feedforward correction without unified perception of the power deviation of the entire network and coordinated adjustment of the voltage reference, it will lead to inconsistent adjustment directions or redundant adjustment amounts at each port, which will exacerbate DC voltage oscillations and weaken the overall inertial response capability of the system.

[0062] Therefore, it is necessary to sum the predicted power deviations of all voltage source converter ports to obtain the total predicted power deviation of the entire network. The total predicted power deviation of the entire network is then multiplied by a preset DC voltage reference correction coefficient to obtain the voltage reference adjustment. This voltage reference adjustment is then superimposed on the base voltage reference value of the common DC bus to generate the corrected common DC bus voltage reference value. This enables active voltage reference dynamic tuning based on the power trend of the entire network, thereby improving the coordinated stability capability of multi-terminal systems under strong fluctuation conditions.

[0063] S104 inputs the active power reference and common DC bus voltage reference values, which have been corrected by the indirect feedforward coordination control layer, to the DC voltage-power collaborative control layer. Then, the active power reference output by the DC voltage-power collaborative control layer is input to the virtual synchronous generator control layer, and the virtual synchronous generator control layer outputs the dq axis voltage reference value, thus completing the multi-layer coordination control process.

[0064] Example 2, refer to Figures 2-9 Based on the above embodiments, a specific implementation of the virtual synchronous power prediction multi-layer coordinated control method can be designed as follows: Based on the construction of AC-side inertia and damping using a virtual synchronous generator (VSG), the first-layer control is located in the local control unit of each VSC converter, primarily addressing the lack of physical inertia and damping in power electronic equipment. In traditional flexible DC transmission systems, converters typically employ vector control (such as dual-loop PI control), which offers extremely fast response but lacks the mechanical inertia of a rotating electric motor. When the grid experiences sudden load changes or fault disturbances, the system rate of change of frequency (RoCoF) becomes extremely high, easily leading to system instability. This invention establishes a virtual synchronous generator (VSG) control layer on the AC side of the converter, mechanistically simulating the external characteristics of a synchronous motor and providing necessary inertial support for the power grid.

[0065] In specific implementation, this invention introduces virtual rotor motion equations (i.e., virtual mechanical equations) and electromagnetic transient equations into the control algorithm. First, the rotor motion equations of a synchronous generator are simulated: Virtual moment of inertia was introduced. and virtual damping coefficient in Represents the mechanical power input to the virtual prime mover. This represents the actual electromagnetic power output by the converter. The physical meaning of this equation is: when the grid load increases, leading to increased output power... Greater than input power At that time, the virtual rotor will release kinetic energy, resulting in a virtual angular velocity. The frequency decreases, thus slowing the rate of frequency drop. Virtual moment of inertia. The existence of this allows the converter to provide power support to the grid during disturbances, just like a traditional generator, utilizing energy storage components (such as DC capacitors), exhibiting "inertia." Simultaneously, the damping term... The function of the generator damping winding was simulated, which can effectively suppress system power oscillations and make the frequency deviation decay rapidly during dynamic processes.

[0066] Furthermore, through the virtual rotor angle equation The integral of the deviation of angular velocity is converted into the work angle. The change in frequency adjusts the phase of the output voltage. This process achieves automatic coupling regulation of active power and frequency. Furthermore, to simulate the frequency regulation function of a speed governor (i.e., primary frequency regulation), virtual mechanical input power... It is not a fixed value, but includes a frequency feedback mechanism: This means that when the system frequency... Below synchronization frequency At this time, the converter will automatically increase the virtual mechanical power input, thereby increasing the active power output and helping to restore the grid frequency.

[0067] Furthermore, this layer controls the amplitude and phase reference values ​​of the final output AC voltage, which are then fed into the inner current loop of the lower layer after coordinate transformation. In this way, the present invention "disguises" the power electronic converter as a synchronous generator with a certain inertia and damping, greatly enhancing the frequency stability and disturbance rejection capability of the flexible DC system when connected to a weak AC grid or operating in an islanded environment. It is the basic physical layer support for achieving stable operation of multi-terminal systems.

[0068] Furthermore, based on the droop characteristic, the DC voltage-power coordinated control layer is located on the common DC bus side, focusing on solving the energy balance and voltage stability problems in multi-terminal flexible DC systems. In a multi-terminal DC system, the DC bus is equivalent to an energy "reservoir," and its voltage level directly reflects the supply and demand balance of active power within the system. If the input power is greater than the output power, the DC voltage increases; conversely, it decreases. To rationally allocate power among multiple converter stations and jointly maintain DC voltage stability, this invention establishes a DC voltage-power coordinated control layer, employing an improved droop control strategy.

[0069] The core idea of ​​this layer of control is to achieve autonomous coordination of multi-terminal converters by using DC voltage as a global common variable, without relying on high-speed communication networks. The droop control characteristic equation defined in this invention is: in, It is the baseline planned power issued by the higher-level dispatcher. This is the reference value for the rated voltage of the common DC bus. Let be the droop coefficient of the i-th converter, which determines the "proactiveness" of the converter in participating in voltage regulation.

[0070] The physical mechanism of this control logic is as follows: When the system experiences a power deficit (e.g., a sudden drop in photovoltaic output at one end), causing a voltage drop on the common DC bus... Below the reference value At that time, according to the above equation, the difference It is negative, which in turn makes The term is positive. This means that the active power reference of each converter is positive. It will be in the original planned value Automatically added based on the existing parameters. Each converter station adjusts its droop coefficient accordingly. The size of the voltage is used to proportionally share the unbalanced power of the system, thereby not only boosting the DC voltage but also achieving dynamic power distribution among the stations.

[0071] Furthermore, to ensure the rationality of the control parameter design, this layer of control is also strictly based on the physical dynamic model of the DC side: This equation reveals the rate of change of DC voltage, the difference between inflow and outflow current, and the equivalent capacitance. The differential relationship between them. The collaborative control layer of this invention designs the droop coefficient. At that time, the capacitance was fully considered. It has good charging and discharging capabilities to avoid voltage overshoot or oscillation caused by excessive adjustment.

[0072] Compared to traditional constant DC voltage control (single-point control) or master-slave control modes, the voltage-power coordinated control strategy adopted in this invention has extremely high reliability. Even if one converter in the system fails and goes out of operation, the other converters can still automatically adjust their power output according to changes in DC voltage and take over the voltage support task, realizing true "plug and play" and N-1 fault redundancy, ensuring the continuous and stable operation of the multi-terminal DC system.

[0073] Furthermore, the third-layer control based on power prediction, an indirect feedforward coordinated control system, is the most innovative part of this invention. Located at the top level of the system architecture, it aims to overcome the lag of traditional feedback control and achieve proactive feedforward regulation. The aforementioned VSG control and droop control are essentially "feedback control," meaning the controller only begins to adjust after a frequency or voltage deviation has occurred (i.e., the disturbance has already had consequences). For distributed power sources with strong volatility and randomness, such as photovoltaic power generation, this lag often leads to severe DC voltage fluctuations, even triggering protection actions.

[0074] To address this, the present invention introduces an indirect feedforward coordination control layer based on power prediction. This layer utilizes advanced time series prediction algorithms or machine learning models, combined with historical operating data and real-time meteorological / load data, to predict the power of each port at a future time (e.g., time t+1). Make short-term forecasts.

[0075] The control logic of this layer comprises three key steps: prediction, deviation calculation, and feedforward correction. First, the system calculates the trend deviation between the predicted power value and the actual measured value at the current moment: This deviation The direction and magnitude of the impending power fluctuations were anticipated. Subsequently, the control layer utilized the feedforward gain. This deviation is converted into a control signal and directly added to correct the active power reference at the bottom layer: The essence of this formula lies in the fact that before the disturbance causes a significant change in the DC voltage Udc (i.e., ΔUdc is still very small), the feedforward term... The system intervenes in advance, adjusting the converter's output power. For example, if it is predicted that the photovoltaic output will drop significantly in the next second, the feedforward control will immediately instruct the converter at the energy storage end or the grid end to increase its output, thereby physically "offsetting" the impending power deficit.

[0076] Furthermore, this layer also features adaptive correction of the DC voltage reference. This is based on the total predicted power deviation of the entire network. The controller dynamically adjusts the voltage reference value of the common DC bus: For example, by appropriately increasing the DC voltage reference value before a large load impact is predicted, and by using capacitors to store energy in advance, the voltage drop depth during the impact can be further reduced.

[0077] It should be noted that, through this "prediction-feedforward" mechanism, this invention transforms the traditional "post-event remedy" into "pre-event prevention." This indirect feedforward coordinated control, combined with the underlying direct feedback control, not only retains the steady-state accuracy of feedback control but also significantly improves the system's dynamic response speed and disturbance rejection performance, perfectly solving the power fluctuation problem caused by a high proportion of new energy sources connecting to the grid.

[0078] Figure 2This diagram illustrates a typical three-terminal flexible DC transmission system structure. Three voltage source converters (VSC1, VSC2, and VSC3) are connected to different AC grids or load sides via AC buses, and their DC sides are connected to a common bipolar DC bus system. This system consists of two parallel DC conductors, positive (+) and negative (-), forming a shared DC network. The diagram specifically labels VSC3 as a "converter transformer," used for electrical isolation and voltage matching between the AC system and the converter. Although other converters are not explicitly labeled, they are typically equipped with corresponding transformers in actual systems. Each VSC serves as a core power electronics unit. The device enables bidirectional energy conversion between AC and DC. Under the control method proposed in this patent, these VSCs not only possess traditional power regulation capabilities but also integrate virtual synchronous generator (VSG) characteristics to provide inertial and damping support. Simultaneously, using the DC bus voltage as a global coordination signal, they autonomously allocate power under conditions without communication. Combined with the top-level power prediction and feedforward mechanism, they achieve proactive response to random disturbances such as photovoltaics and loads. The entire topology supports flexible multi-terminal interconnection, plug-and-play operation, and N-1 fault redundancy, serving as the physical carrier and typical application scenario of the "virtual synchronous-power prediction multi-layer coordinated control method" of this invention.

[0079] Figure 3 This is a functional block diagram of the single-ended VSC virtual synchronous machine control layer, demonstrating the complete implementation structure of the virtual synchronous generator (VSG) control strategy. Its core is to simulate the mechanical motion and electromagnetic characteristics of a synchronous generator to endow the power electronic converter with inertia and damping capabilities. The input active power reference value P and reactive power reference value Q are fed into the virtual mechanical equation module J·dω / dt to calculate the rotor dynamic response. The output angular velocity change rate is then sent to the virtual rotor angle integration module to generate the virtual rotor angle δ. Simultaneously, P and Q also participate as inputs in the voltage reference generation module's calculations. Combined with the AC side voltage Uac and current Iac, the actual active power is obtained through the P / Q calculation module. The power Pe and reactive power Qe are compared with the reference value to form an error signal used to adjust the voltage reference value. This voltage reference value is then converted into a dq-axis voltage command by the dq coordinate transformation module based on the virtual rotor angle δ and the grid synchronization angular velocity ω. Finally, the current inner loop PI control module receives the dq-axis voltage command and the actual AC side voltage and current feedback signal to perform closed-loop control, generating a modulation signal to drive the VSC converter. The entire process realizes a step-by-step closed loop from power command to voltage command to current control, enabling the VSC to exhibit dynamic behavior similar to a synchronous generator during operation, thereby improving system stability, enhancing frequency support capability, and improving grid connection performance.

[0080] Figure 4This is a block diagram of multi-terminal VSC DC voltage-power coordinated control, illustrating the structure of a multi-terminal flexible DC system that achieves communication-free coordinated control between converter stations by using a common DC bus voltage as a global signal. The common DC bus voltage U... dc The DC voltage deviation calculation modules of VSC1, VSC2 and VSC3 are collected in real time and sent to each module respectively. Each module calculates the deviation ΔU between the local DC voltage and the reference value. dc The deviation is processed by the droop control loop to generate an active power reference value P*. This power reference value is used as input to the virtual synchronous generator (VSG) control layer of the corresponding VSC, thereby enabling each converter station to autonomously adjust its output power according to the local voltage deviation, achieving the purpose of coordinated control of power distribution and DC voltage stability. The whole process does not rely on inter-station communication, has good plug-and-play and fault redundancy capabilities, and can effectively cope with source load fluctuations and network disturbances, improving the stability and reliability of system operation.

[0081] Figure 5 The block diagram of the coordinated control logic for power prediction and indirect feedforward demonstrates the top-level control structure for active predictive power regulation in a multi-terminal VSC flexible DC system. Its inputs are historical power data and real-time measurement data, which are first fed into the power prediction module to calculate the future power value P. pred,i The estimate is then used to calculate the difference ΔP between the predicted value and the current actual value through the prediction deviation calculation module. pred,i This deviation is fed forward by gain K ff,i After being amplified, it is used as the feedforward correction amount ΔP pred,i The droop control module, introduced into the DC voltage-power co-control layer, dynamically corrects the original power reference value P to generate a new comprehensive power reference value Pi. * This value is then passed to the virtual synchronous generator (VSG) control layer of each VSC for subsequent current inner loop control. The entire process realizes an indirect feedforward compensation mechanism based on predictive information, enabling the system to respond in advance to disturbances such as photovoltaic output fluctuations and load changes, improve power point tracking accuracy and system dynamic performance, enhance adaptability to uncertainties, and thus optimize overall operational stability and efficiency.

[0082] Figure 6This diagram illustrates the overall architecture of a multi-layered coordinated control system, showcasing a hierarchical coordinated control structure for a multi-terminal VSC flexible DC system. From top to bottom, it consists of a power prediction layer, a DC voltage-power coordinated control layer, a virtual synchronous machine (VSG) control layer, and a current inner loop and modulation layer, ultimately acting on the VSC power unit. The top-level power prediction layer generates a future active power reference value P* based on historical and real-time data and passes it to the next layer. The DC voltage-power coordinated control layer receives this reference value and, combined with the common DC bus voltage deviation, generates a new DC voltage reference value U_dc_ref through a droop control strategy, which is then passed to the VSC. The G control layer simulates the dynamic characteristics of a synchronous generator. Based on U_dc_ref, it calculates the reference values ​​U_dq_ref and I_dq_ref for the dq axis voltage and current, and sends them to the current inner loop and modulation layer for closed-loop control. This generates drive signals to adjust the output behavior of the VSC power unit. The entire architecture realizes a progressive control logic of "prediction-coordination-execution," organically combining power prediction, voltage coordination, and virtual inertia to form a multi-layer control system with feedforward compensation, autonomous coordination, and dynamic support capabilities. This significantly improves the system's stability, response speed, and operating efficiency in the context of new energy fluctuations.

[0083] Figure 7 This is a schematic diagram of the equivalent dynamic model of the DC side of a single-ended VSC, illustrating the dynamic relationship between capacitor energy storage and current on the DC side of the VSC under simplified modeling, where U dc The node represents the DC bus voltage, C dc This is the equivalent DC-side capacitance, used to characterize the system's energy storage characteristics. This node connects two branches: one for the DC line current I. line One line represents the current injected from upstream or the converter; the other line represents the load or downstream converter current I. load This represents the current flowing to the load or downstream equipment. According to Kirchhoff's current law, the charging and discharging process of a capacitor satisfies the differential equation C. dc ·dU dc / dt=I line -I load The DC bus voltage change rate is determined by the difference between the input current and the output current. This model reflects the dynamic response mechanism of the DC side voltage and is the basis for analyzing and designing DC voltage control strategies. In particular, it can be used in multi-terminal flexible DC systems to evaluate voltage fluctuations, power disturbance propagation and stability boundaries, and support the design and parameter tuning of control methods such as droop control and virtual impedance.

[0084] Figure 8This diagram illustrates the active power distribution and DC voltage droop characteristics across multiple terminals, demonstrating the principle of autonomous and coordinated active power distribution achieved by each converter station in a multi-terminal VSC flexible DC system through droop control. The diagram visually reflects the dynamic process of power distribution and the voltage-power coupling relationship in a multi-terminal system, serving as a core basis for understanding DC voltage-power coordinated control strategies.

[0085] Figure 9 This diagram illustrates the functional modules of a multi-terminal VSC flexible DC system control device, showcasing the core architecture of the entire control system and the information flow relationships between its various functional modules. External measurement inputs serve as the basic data entering the control device. First, the power prediction module estimates future power based on historical and real-time data, generating a predicted value which is then sent to the indirect feedforward coordination module. This module calculates the prediction deviation and corrects the power reference value using feedforward gain. Simultaneously, the DC voltage-power collaborative control module receives signals from the power prediction module and local DC voltage information, combines it with a droop control strategy to generate an active power reference value, and then merges it with the indirect feedforward signal to output a comprehensive power command. This command is transmitted to the virtual synchronous generator (VSG) control module, which simulates the inertia and damping characteristics of a synchronous generator to generate dq-axis voltage and current reference values. These values ​​are then sent to the current control and modulation module for closed-loop regulation, ultimately outputting a drive signal to control the operation of the VSC power unit. The entire device achieves a complete multi-layered coordinated control process from power prediction, feedforward compensation, voltage-power collaboration to virtual synchronous control and the inner current loop. It possesses excellent dynamic response capabilities and system stability, making it suitable for multi-terminal flexible DC transmission systems with a high proportion of renewable energy integration.

[0086] Example 3, referring to Figure 10 This embodiment also provides a virtual synchronous power prediction multi-layer coordination control system, including: The local control unit, located in each voltage source converter, is used to run the virtual synchronous generator control layer, receive active power reference and AC voltage reference, and generate dq axis voltage reference values ​​through virtual mechanical equations and virtual rotor angle equations. The upper-level coordination and control unit is located on the common DC bus side and includes a DC voltage-power coordinated control module and an indirect feedforward coordinated control module; The DC voltage-power coordinated control module is used to receive the planned active power of each voltage source converter, the actual DC side voltage value, and the reference value of the common DC bus voltage, and generate a corrected active power reference through droop adjustment. The indirect feedforward coordination control module is used to predict the future active power of each port based on historical operating data and real-time measurement data, calculate the predicted power deviation, and generate the feedforward corrected active power reference and the corrected common DC bus voltage reference value. The upper-level coordination control unit transmits the feedforward-corrected active power reference and the corrected common DC bus voltage reference value to each local control unit, forming a three-level cascaded control architecture.

[0087] The above-mentioned unit modules can be embedded in the processor of the electronic device in hardware form or independent of it, or they can be stored in the memory of the electronic device in software form, so that the processor can call and execute the corresponding operations of the above modules.

[0088] This embodiment also provides an electronic device, which can be a terminal, and its internal structure diagram can be as follows: Figure 10 As shown, the electronic device includes a processor, memory, communication interface, display screen, and input devices connected via a system bus. The processor provides computing and control capabilities. The memory includes a non-volatile storage medium and internal memory. The non-volatile storage medium stores the operating system and computer programs. The internal memory provides an environment for the operation of the operating system and computer programs in the non-volatile storage medium. The communication interface is used for wired or wireless communication with external terminals; wireless communication can be achieved through Wi-Fi, carrier networks, NFC (Near Field Communication), or other technologies. When the computer program is executed by the processor, it implements a virtual synchronous power prediction multi-layer coordinated control method. The display screen can be an LCD screen or an e-ink screen. The input devices can be a touch layer covering the display screen, buttons, a trackball, or a touchpad on the device's casing, or an external keyboard, touchpad, or mouse.

[0089] This embodiment also provides a computer-readable storage medium on which a computer program is stored, and when the computer program is executed by a processor, it performs the following steps: A virtual synchronous generator control layer is established on the AC side of each voltage source converter, and AC voltage amplitude reference and phase angle reference are generated through virtual mechanical equations and virtual rotor angle equations. A DC voltage-power collaborative control layer is established on the side of the common DC bus. The active power reference of each voltage source converter is correlated with the deviation between the corresponding DC side voltage and the common DC bus voltage reference value to generate an active power reference with droop adjustment. An indirect feedforward coordination control layer based on power prediction is established above the DC voltage-power coordinated control layer. The predicted power deviation is calculated using the power prediction values ​​of each port, and the active power reference and common DC bus voltage reference values ​​of each voltage source converter are corrected through the feedforward channel. The active power reference and common DC bus voltage reference values, corrected by the indirect feedforward coordination control layer, are input to the DC voltage-power collaborative control layer. The active power reference output by the DC voltage-power collaborative control layer is then input to the virtual synchronous generator control layer, which outputs the dq axis voltage reference value, thus completing the multi-layer coordination control process.

[0090] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

[0091] Although preferred embodiments of the invention have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including both the preferred embodiments and all changes and modifications falling within the scope of the invention.

[0092] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

Claims

1. A virtual synchronous power prediction multi-layer coordinated control method, characterized in that, include: A virtual synchronous generator control layer is established on the AC side of each voltage source converter, and AC voltage amplitude reference and phase angle reference are generated through virtual mechanical equations and virtual rotor angle equations. A DC voltage-power collaborative control layer is established on the side of the common DC bus. The active power reference of each voltage source converter is correlated with the deviation between the corresponding DC side voltage and the common DC bus voltage reference value to generate an active power reference with droop adjustment. An indirect feedforward coordination control layer based on power prediction is established above the DC voltage-power coordinated control layer. The predicted power deviation is calculated using the power prediction values ​​of each port, and the active power reference and common DC bus voltage reference values ​​of each voltage source converter are corrected through the feedforward channel. The active power reference and common DC bus voltage reference values, corrected by the indirect feedforward coordination control layer, are input to the DC voltage-power collaborative control layer. The active power reference output by the DC voltage-power collaborative control layer is then input to the virtual synchronous generator control layer, which outputs the dq axis voltage reference value, thus completing the multi-layer coordination control process.

2. The virtual synchronous power prediction multi-layer coordinated control method as described in claim 1, characterized in that, The establishment of a virtual synchronous generator control layer on the AC side of each voltage source converter includes: The change in virtual angular velocity is calculated based on the virtual moment of inertia, virtual damping coefficient, grid synchronization angular velocity, current virtual angular velocity, virtual mechanical input power, and actual active power output. The virtual rotor phase angle is obtained by integrating the difference between the virtual angular velocity change and the grid synchronous angular velocity. An AC voltage amplitude reference and a phase angle reference are generated based on the virtual angular velocity and the virtual rotor phase angle.

3. The virtual synchronous power prediction multi-layer coordinated control method as described in claim 2, characterized in that, The virtual mechanical input power is obtained by superimposing the planned active power issued by the superior dispatcher with the frequency deviation ratio adjustment amount. The frequency deviation ratio adjustment amount is determined by multiplying the difference between the grid synchronous angular velocity and the current virtual angular velocity by a preset ratio coefficient.

4. The virtual synchronous power prediction multi-layer coordinated control method as described in claim 3, characterized in that, The establishment of a DC voltage-power coordinated control layer on the common DC bus side includes: Obtain the planned active power of each voltage source converter issued by the superior dispatcher; Obtain the actual voltage values ​​on the DC side of each voltage source converter and the voltage reference value of the common DC bus; The droop adjustment amount is obtained by multiplying the DC voltage droop coefficient of each voltage source converter with the deviation between the corresponding actual DC side voltage value and the reference value of the common DC bus voltage. The corresponding droop adjustment is subtracted from the planned active power of each voltage source converter to generate a droop-adjusted active power reference.

5. The virtual synchronous power prediction multi-layer coordinated control method as described in claim 4, characterized in that, The establishment of a DC voltage-power coordinated control layer on the common DC bus side also includes: Based on the charging and discharging dynamic characteristics of the equivalent capacitance on the DC side of each voltage source converter, the difference between the DC current flowing into the voltage source converter and the DC current flowing out of the voltage source converter is taken as the capacitance current. The state of the DC side voltage of the voltage source converter is updated based on the capacitor current.

6. The virtual synchronous power prediction multi-layer coordinated control method as described in claim 5, characterized in that, The establishment of an indirect feedforward coordination control layer based on power prediction above the DC voltage-power coordinated control layer includes: Based on historical operating data and real-time measurement data, predict the active power value of each voltage source converter port at a future set time point; The predicted active power value of each port is compared with the actual active power output of the corresponding voltage source converter at the current moment to obtain the predicted power deviation. Each predicted power deviation is multiplied by its corresponding feedforward gain coefficient and then superimposed onto the droop-adjusted active power reference to generate a feedforward-corrected active power reference.

7. The virtual synchronous power prediction multi-layer coordinated control method as described in claim 6, characterized in that, The establishment of an indirect feedforward coordination control layer based on power prediction above the DC voltage-power coordinated control layer further includes: The predicted power deviations at all voltage source converter ports are summed to obtain the total predicted power deviation for the entire network. Multiply the sum of the predicted power deviations of the entire network by a preset DC voltage reference correction coefficient to obtain the voltage reference adjustment amount; The voltage reference adjustment is superimposed on the base voltage reference value of the common DC bus to generate the corrected common DC bus voltage reference value.

8. A virtual synchronous power prediction multi-layer coordinated control system, using the method described in any one of claims 1 to 7, characterized in that, include: The local control unit, located in each voltage source converter, is used to run the virtual synchronous generator control layer, receive active power reference and AC voltage reference, and generate dq axis voltage reference values ​​through virtual mechanical equations and virtual rotor angle equations. The upper-level coordination and control unit is located on the common DC bus side and includes a DC voltage-power coordinated control module and an indirect feedforward coordinated control module; The DC voltage-power coordinated control module is used to receive the planned active power of each voltage source converter, the actual DC side voltage value, and the reference value of the common DC bus voltage, and generate a corrected active power reference through droop adjustment. The indirect feedforward coordination control module is used to predict the future active power of each port based on historical operating data and real-time measurement data, calculate the predicted power deviation, and generate a feedforward corrected active power reference and a corrected common DC bus voltage reference value. The upper-level coordination control unit transmits the feedforward-corrected active power reference and the corrected common DC bus voltage reference value to each local control unit, forming a three-level cascaded control architecture.

9. An electronic device comprising a memory and a processor, wherein the memory stores a computer program, characterized in that, When the processor executes the computer program, it implements the steps of the virtual synchronous power prediction multilayer coordinated control method according to any one of claims 1 to 7.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the steps of the virtual synchronous power prediction multilayer coordinated control method according to any one of claims 1 to 7.

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