A method, system, device, and medium for adaptive virtual impedance droop control

Abstract

This invention proposes an adaptive virtual impedance droop control method, system, device, and medium, relating to the field of droop control. The method includes: calculating the standardized reactive power of each local node and neighboring node based on the equivalent output impedance and reactive power droop coefficient; generating a correction amount for the virtual impedance based on the accelerated consensus algorithm and the standardized reactive power of each local node and neighboring node; adjusting the virtual impedance in the distributed grid topology according to the correction amount of the virtual impedance to obtain the adjusted dynamic virtual impedance; calculating the virtual impedance voltage drop based on the adjusted dynamic virtual impedance; calculating the feedforward compensation voltage reference value; calculating the common compensation amount of the preset virtual leader node and the local compensation amount of each local node and neighboring node to obtain the total voltage compensation command; adjusting the feedforward compensation voltage reference value according to the total voltage compensation command to obtain a voltage stabilization scheme, using the dynamic virtual impedance as the power distribution scheme.

Description

Technical Field

[0001] This invention relates to the field of droop control technology, specifically to a method, system, device, and medium for adaptive virtual impedance droop control. Background Technology

[0002] Current parallel inverter systems mostly employ traditional droop control or fixed virtual impedance control schemes, which suffer from defects such as uneven reactive power distribution and insufficient voltage support. Although traditional droop control can achieve autonomous power distribution without communication, it is prone to circulating current due to the mismatch of parameters such as inverter output impedance and rated power. Under heavy load conditions, the voltage drop at the point of common coupling (PCC) is significant, resulting in insufficient voltage stability. Existing improvement schemes cannot simultaneously solve the two core problems of uneven power distribution and insufficient voltage support, and some schemes have limited power coupling or voltage compensation effects, resulting in circulating current. Summary of the Invention

[0003] This invention addresses the problems existing in the prior art by providing a method, system, device, and medium for adaptive virtual impedance droop control, thereby resolving the issues of uneven reactive power distribution and circulating current caused by line impedance mismatch.

[0004] To achieve the above objectives, the technical solution adopted by the present invention is as follows: The initial voltage command, equivalent output impedance, and reactive power droop coefficient of the distributed power grid topology are obtained, and the standardized reactive power of each local node and neighboring node is calculated based on the equivalent output impedance and reactive power droop coefficient. Based on the accelerated consensus algorithm and the correction amount of the standardized reactive power generated by each local node and neighbor node, the virtual impedance in the distributed power grid topology is adjusted according to the correction amount of the virtual impedance to obtain the adjusted dynamic virtual impedance. The virtual impedance voltage drop is calculated based on the adjusted dynamic virtual impedance feedforward, and the feedforward compensation voltage reference value is calculated based on the initial voltage command and the dynamic virtual impedance voltage drop. The voltage of the distributed power grid topology is controlled in a hierarchical and coordinated manner. The total voltage compensation command is obtained by calculating the common compensation amount of the preset virtual leader node and the local compensation amount of each local node and neighbor node. The feedforward compensation voltage reference value is adjusted according to the total voltage compensation command to obtain a voltage stabilization scheme, and the dynamic virtual impedance is used as the power distribution scheme.

[0005] In some embodiments, the process of calculating the standardized reactive power of each local node and neighboring node based on the equivalent output impedance and reactive power droop factor includes: Configure distributed computing nodes for distributed power grid topologies; Calculate the normalized reactive power of this node and the normalized reactive power of neighboring nodes based on the equivalent output impedance and reactive power droop factor. The standardized reactive power refers to the relative size of the actual output reactive power to its rated reactive power under the current droop coefficient.

[0006] In some embodiments, the process of adjusting the virtual impedance in the distributed grid topology based on the correction amount of the virtual impedance generated by the accelerated consensus algorithm and the normalized reactive power of each local node and neighboring nodes, to obtain the adjusted dynamic virtual impedance, includes: The consensus error is calculated by averaging the normalized reactive power of the local node and the normalized reactive power of the neighboring nodes based on the accelerated consensus algorithm. The consistency error is passed through a proportional-integral regulator to generate a correction amount for the virtual impedance; The virtual impedance in the distributed power grid topology is dynamically adjusted based on the correction amount to obtain the adjusted dynamic virtual impedance.

[0007] In some embodiments, the process of calculating the virtual impedance voltage drop based on the dynamic virtual impedance and calculating the feedforward compensation voltage reference value based on the initial voltage command and the virtual impedance voltage drop includes: In a synchronous rotating coordinate system, the virtual impedance voltage drop is obtained by feedforward calculation using the sum of the output current of the distributed power grid topology and the dynamic virtual impedance. The initial voltage command minus the virtual impedance voltage drop yields the feedforward compensation voltage reference value.

[0008] In some embodiments, the process of performing hierarchical coordinated control of voltage in a distributed power grid topology, and calculating the common compensation amount of a preset virtual leader node and the local compensation amounts of each local node and neighbor node to obtain a total voltage compensation command, includes: Hierarchical and coordinated voltage control for distributed power grid topologies; Setting up a virtual leader node brings the bus voltage at the common connection point of the distributed power grid topology back to the rated value, calculates the distributed consistency correction amount, and uses it as the common compensation amount. The local voltage information of each local node and its neighboring nodes is converged to an optimal common small offset, which is used as the local compensation amount. The common compensation amount and the local compensation amount are merged into a total voltage compensation command.

[0009] In some embodiments, the voltage stabilization scheme includes modifying the initial voltage command according to the total voltage compensation command to obtain a final voltage amplitude command sent to the inner loop controller; The power allocation scheme includes a dynamic virtual impedance where the ratio of the equivalent output impedance of the distributed grid topology to its respective reactive power droop coefficient tends to converge, and the dynamic virtual impedance serves as the impedance matching condition for reactive power allocation.

[0010] In some embodiments, the dynamic virtual impedance formula is: ; in, Let be the dynamic virtual impedance of the i-th DG. To fix the virtual resistance of the base, For fixed foundation virtual reactance, For correction amount, To map the correction amount to the gain factor of the actual resistance, To map the correction amount to the actual reactance, The angular frequency of the synchronously rotating coordinate system; The formula for the voltage stabilization scheme is: ; in, This is a voltage amplitude command. This is the system's nominal voltage. To output reactive power locally, Rated reactive power, The droop coefficient is... The d-axis component of the DGi output current. This represents the q-axis component of the DGi output current. For virtual resistance, Virtual reactance, This is a total voltage compensation command.

[0011] This invention proposes an adaptive virtual impedance droop control system, comprising: The reactive power distribution unit is configured to obtain the initial voltage command, equivalent output impedance and reactive power droop coefficient of the distributed power grid topology, and calculate the standardized reactive power of each local node and neighboring node based on the equivalent output impedance and reactive power droop coefficient. The dynamic adjustment unit is configured to adjust the virtual impedance in the distributed power grid topology based on the accelerated consensus algorithm and the standardized reactive power generation virtual impedance of each local node and neighboring node, and to obtain the adjusted dynamic virtual impedance according to the virtual impedance adjustment amount. The feedforward compensation unit is configured to calculate the virtual impedance voltage drop based on the adjusted dynamic virtual impedance feedforward, and to calculate the feedforward compensation voltage reference value based on the initial voltage command and the dynamic virtual impedance voltage drop. The hierarchical coordination unit is configured to perform hierarchical coordinated control of voltage in a distributed power grid topology, and calculates the common compensation amount of the preset virtual leader node and the local compensation amount of each local node and neighbor node to obtain the total voltage compensation command. The control output unit is configured to adjust the feedforward compensation voltage reference value according to the total voltage compensation command to obtain a voltage stabilization scheme, and to use the dynamic virtual impedance as a power distribution scheme.

[0012] This invention proposes a computer device, comprising: At least one processor; and a memory storing a computer program executable on the processor, wherein the processor, when executing the program, performs the steps of the method for adaptive virtual impedance droop control.

[0013] The present invention provides a computer-readable storage medium storing a computer program that, when executed by a processor, performs the steps of the method for adaptive virtual impedance droop control.

[0014] Compared with the prior art, the present invention has the following beneficial effects: This invention proposes an adaptive virtual impedance droop control method, system, device, and medium. The method includes: acquiring the initial voltage command, equivalent output impedance, and reactive power droop coefficient of a distributed power grid topology; calculating the standardized reactive power of each local node and neighboring node based on the equivalent output impedance and reactive power droop coefficient; generating a correction amount for the virtual impedance based on an accelerated consensus algorithm and the standardized reactive power of each local node and neighboring node; adjusting the virtual impedance in the distributed power grid topology according to the correction amount to obtain the adjusted dynamic virtual impedance; calculating the virtual impedance voltage drop based on the adjusted dynamic virtual impedance; calculating a feedforward compensation voltage reference value based on the initial voltage command and the dynamic virtual impedance voltage drop; performing hierarchical collaborative control of the voltage of the distributed power grid topology; calculating the common compensation amount of a preset virtual leader node and the local compensation amount of each local node and neighboring node to obtain a total voltage compensation command; adjusting the feedforward compensation voltage reference value according to the total voltage compensation command to obtain a voltage stabilization scheme, using the dynamic virtual impedance as a power allocation scheme.

[0015] This invention enables precise power distribution in parallel inverter systems and suppresses circulating current generation; at the same time, it compensates for PCC voltage drops, improves the voltage stability of the system under different load conditions, and maintains the advantages of traditional droop control being simple and easy to use.

[0016] This invention improves system performance without communication dependency through the collaborative design of adaptive virtual impedance and secondary voltage compensation, thus possessing technical competitiveness. Attached Figure Description

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

[0018] Figure 1 The flowchart of an adaptive virtual impedance droop control method provided by the present invention is shown.

[0019] Figure 2 This invention provides a system block diagram for adaptive virtual impedance droop control.

[0020] Figure 3 A schematic diagram of the structure of an embodiment of the computer device provided by the present invention.

[0021] Figure 4 This is a schematic diagram of an embodiment of the computer-readable storage medium provided by the present invention.

[0022] Figure 5 The virtual impedance control diagram in the dq coordinate system is shown in one embodiment of the adaptive virtual impedance droop control method provided by the present invention.

[0023] Figure 6 An equivalent circuit diagram of adaptive virtual impedance in one embodiment of the adaptive virtual impedance droop control method provided by the present invention.

[0024] Figure 7 A voltage fluctuation diagram at the parallel point in one embodiment of an adaptive virtual impedance droop control method provided by the present invention.

[0025] Figure 8 The reactive power distribution diagram of a dual-machine system is provided in one embodiment of the adaptive virtual impedance droop control method of the present invention. Detailed Implementation

[0026] The present invention will be further described below with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solutions of the present invention and should not be construed as limiting the scope of protection of the present invention. It should be noted that the following detailed descriptions are exemplary and intended to provide further explanation of this application.

[0027] It should be noted that all uses of "first" and "second" in the embodiments of the present invention are for the purpose of distinguishing two entities or parameters with the same name but different names. It is clear that "first" and "second" are only for the convenience of expression and should not be construed as limiting the embodiments of the present invention. Subsequent embodiments will not explain this in detail.

[0028] This invention proposes an adaptive virtual impedance droop control method; please refer to [link / reference]. Figure 1 ,include: S1. Obtain the initial voltage command, equivalent output impedance and reactive power droop coefficient of the distributed power grid topology, and calculate the standardized reactive power of each local node and neighboring node based on the equivalent output impedance and reactive power droop coefficient. S2. Based on the accelerated consensus algorithm and the standardized reactive power of each local node and neighboring node, the virtual impedance in the distributed power grid topology is adjusted according to the correction amount of the virtual impedance to obtain the adjusted dynamic virtual impedance. S3. The virtual impedance voltage drop is calculated based on the adjusted dynamic virtual impedance feedforward, and the feedforward compensation voltage reference value is calculated based on the initial voltage command and the dynamic virtual impedance voltage drop. S4. Perform hierarchical coordinated control of voltage in the distributed power grid topology, and calculate the common compensation amount of the preset virtual leader node and the local compensation amount of each local node and neighbor node to obtain the total voltage compensation command. S5. Adjust the feedforward compensation voltage reference value according to the total voltage compensation command to obtain a voltage stabilization scheme, and use the dynamic virtual impedance as the power distribution scheme.

[0029] This invention aims to solve the problems of uneven reactive power distribution and circulating current caused by line impedance mismatch. Its core idea is to dynamically adjust the virtual impedance value of each inverter through distributed coordination, making its equivalent output impedance proportional to its respective reactive power droop factor, thereby automatically meeting the impedance matching conditions for precise reactive power distribution. This method does not require measuring or knowing the actual line impedance parameters; it only requires the exchange of a small amount of information between adjacent nodes.

[0030] To ensure that the reactive power output of each DG unit is strictly distributed according to the rated capacity ratio, that is... This balances the output voltage of each unit and suppresses circulating current in the parallel system.

[0031] For systems with inductive output impedance, precise reactive power distribution must meet certain conditions. ,in For line inductance Resistance to virtual reality The sum. By introducing adjustable virtual impedance. And design control laws to make the equivalent inductive resistance of all DGs Its reactive droop coefficient The ratios converge, that is... If so, the above allocation conditions can be automatically met.

[0032] This invention achieves voltage stability and balanced reactive power distribution through collaborative voltage and power control in distributed power grids. It obtains the initial voltage command rated voltage value, equivalent output impedance (reflecting the inherent impedance characteristics of the inverter or power supply), and the reactive power droop factor (characterizing the reactive power distribution ratio). Through standardization, the reactive power droop factor is combined with the equivalent output impedance to calculate standardized reactive power. This eliminates reactive power distribution deviations caused by impedance differences between nodes. For example, if node A has an equivalent output impedance of 0.5Ω and a droop factor of 0.1, while node B has 1Ω and a droop factor of 0.2, the standardized reactive power distribution ratio between the two nodes will more closely approximate the capacity ratio.

[0033] The accelerated consensus algorithm simulates the rapid information propagation mechanism in group behavior, enabling the virtual impedance of each node to approach the global optimum over multiple iterations. For example, initially, the virtual impedance of node A is set to 0.3Ω and that of node B is 0.6Ω. Through information exchange between neighboring nodes, the algorithm gradually reduces the difference between the two, eventually converging to 0.4Ω, thus achieving impedance matching.

[0034] Once the dynamic virtual impedance is determined, the resulting voltage drop is calculated. For example, when the virtual impedance is 0.4Ω and the current is 20A, the voltage drop is 8V. Combined with the initial voltage command, a feedforward compensation voltage reference value is generated. For example, the rated voltage is 380V minus 8V, which equals 372V, thus offsetting the effect of impedance voltage drop on voltage in advance.

[0035] The overall compensation command adjusts the feedforward reference value, correcting 372V to 375V to cope with additional disturbances and generating a voltage stabilization scheme. The dynamic virtual impedance serves as the basis for power allocation, ensuring reactive power is distributed proportionally to node capacity. For example, in a three-node system, the capacity ratio of nodes 1-3 is 2:3:5. After standardization, the virtual impedances are 0.2Ω, 0.3Ω, and 0.5Ω respectively, resulting in a reactive power allocation ratio close to 2:3:5, achieving balance.

[0036] In some embodiments, please refer to Figure 1 The process of calculating the standardized reactive power of each local node and neighboring node based on the equivalent output impedance and reactive power droop factor includes: Configure distributed computing nodes for distributed power grid topologies; Calculate the normalized reactive power of this node and the normalized reactive power of neighboring nodes based on the equivalent output impedance and reactive power droop factor. The standardized reactive power refers to the relative size of the actual output reactive power to its rated reactive power under the current droop coefficient.

[0037] Each DGi measures local output reactive power. And calculate its "standardized reactive power". This value represents the relative magnitude of the actual output reactive power to its rated reactive power capacity under the current droop factor. Each DG periodically sends its own data to its neighboring nodes through a sparse communication network. and receive neighbors' .

[0038] In distributed power grids, the core purpose of calculating standardized reactive power is to eliminate the problem of uneven reactive power distribution caused by differences in equivalent output impedance and reactive power droop coefficient among different nodes. By standardizing the ratio of actual output reactive power to rated reactive power capacity, fair distribution according to node capacity ratio can be achieved.

[0039] Each distributed computing node, i.e., the inverter or energy storage device, is assigned a unique identifier, and a neighbor node communication topology is constructed. For example, node A establishes connections with neighboring nodes B and C via wireless communication, forming a local information exchange network. Each node needs to store its own equivalent output impedance (0.5Ω for node A), reactive power droop factor (0.1Ω for node A), and rated reactive power capacity (100kVar for node A).

[0040] When calculating normalized reactive power, a node first calculates its own normalized value based on local parameters: The actual output reactive power, Node A's current output of 30kVar, is divided by its rated reactive power capacity, resulting in a local normalized reactive power of 30kVar / 100kVar = 0.3. Simultaneously, the node obtains the equivalent output impedance and droop factor of its neighboring nodes through communication. Assuming Node B has an equivalent output impedance of 0.8Ω, a droop factor of 0.15, a rated capacity of 150kVar, and an actual output of 45kVar, its normalized reactive power is 45 / 150 = 0.3. If the neighboring node parameters are unknown, historical data or default values ​​can be used for initialization.

[0041] Standardized reactive power eliminates the influence of node capacity differences and directly reflects the ratio of reactive power output to its own capacity. For example, if the standardized reactive power of nodes A and B is 0.3, it means that both nodes are utilizing 30% of their rated reactive power capacity. Even if node B's absolute output value of 45kVar is higher, its relative contribution is consistent with node A's 30kVar.

[0042] In some embodiments, please refer to Figure 1 The process of adjusting the virtual impedance in the distributed grid topology based on the correction amount of the virtual impedance generated by the accelerated consensus algorithm and the standardized reactive power of each local node and neighboring nodes, to obtain the adjusted dynamic virtual impedance, includes: The consensus error is calculated by averaging the normalized reactive power of the local node and the normalized reactive power of the neighboring nodes based on the accelerated consensus algorithm. The consistency error is passed through a proportional-integral regulator to generate a correction amount for the virtual impedance; The virtual impedance in the distributed power grid topology is dynamically adjusted based on the correction amount to obtain the adjusted dynamic virtual impedance.

[0043] Based on the received neighbor information, each DGi calculates the difference between its standardized reactive power and the neighbor's average value, i.e., the consistency error. .

[0044] ; in, These are the adjacency matrix elements of the communication topology. Let DG_i be the set of neighbors. This error... Driven by all DG The values ​​tend to be consistent, which is precisely the proportional distribution of reactive power. The equivalent condition of ).

[0045] Consistency error As input, a correction amount for the virtual impedance is generated through a proportional-integral (PI) regulator. This correction amount is used to adjust the virtual impedance setting in real time.

[0046] ; in, Let be the regulator parameters. s is the complex frequency domain integral element of the PI controller regulation parameters. Therefore, the dynamic virtual impedance of the i-th DG is... for: ; Right now: ; ; in, This represents the virtual resistance value that varies over time (instantaneous value in the time domain). The virtual inductance value varies with time (instantaneous value in the time domain), where t is time; Fixed base virtual impedance (used to ensure the output impedance is inductive and to enhance damping). To convert dimensionless correction quantities Gain coefficient mapped to actual resistance / inductance values.

[0047] In the dynamic adjustment of virtual impedance in distributed power grids, the accelerated consensus algorithm, by simulating the rapid information propagation mechanism in swarm intelligence, enables the standardized reactive power of each node to converge quickly to a globally consistent value, thereby eliminating the uneven reactive power distribution caused by impedance differences. Nodes calculate the consensus error based on the accelerated consensus algorithm. Each node periodically collects its own standardized reactive power and the standardized reactive power of its neighboring nodes, calculates the neighboring average value through a weighted average, and then subtracts its own value to obtain the error. The accelerated consensus algorithm accelerates convergence by introducing the error from the previous time step, enabling nodes to perceive the global trend more quickly.

[0048] The consistency error input proportional-integral (PI) controller generates a virtual impedance correction. The PI controller responds quickly to the current error through the proportional element (Kp), while the integral element (Ki) accumulates historical errors to eliminate steady-state deviations, driving the virtual impedance to adjust in the direction of reducing the error. The node dynamically adjusts the virtual impedance according to the correction, and the adjusted dynamic virtual impedance is fed back to the reactive power distribution stage in real time, forming a closed-loop control.

[0049] In some embodiments, please refer to Figure 1 The process of calculating the virtual impedance voltage drop based on the dynamic virtual impedance, and calculating the feedforward compensation voltage reference value based on the initial voltage command and the virtual impedance voltage drop, includes: In a synchronous rotating coordinate system, the virtual impedance voltage drop is obtained by feedforward calculation using the sum of the output current of the distributed power grid topology and the dynamic virtual impedance. The initial voltage command minus the virtual impedance voltage drop yields the feedforward compensation voltage reference value.

[0050] Adjusted virtual impedance This needs to be implemented in the control algorithm. In the synchronous rotating coordinate system (dq coordinate system), the corresponding virtual voltage drop is introduced into the voltage reference command through feedforward calculation of the output current.

[0051] ; in, This represents the dq-axis component of the DGi output current. This represents the dq-axis component of the calculated virtual impedance voltage drop.

[0052] This virtual voltage drop will be subtracted from the initial voltage reference command output by the droop control module to form the corrected voltage reference value sent to the inner loop voltage controller. .

[0053] ; Through the closed-loop adjustment based on the consensus algorithm described above, the system can automatically find a set of dynamic virtual impedance values. When the system converges to steady state, it satisfies Thus ensuring This achieves precise proportional distribution of reactive power. Simultaneously, because the equivalent output impedance of each distributed generator (DG) is reshaped to a matched state, their terminal voltages naturally tend to be consistent, effectively suppressing system circulating current. This process is entirely distributed, relying solely on local measurements and neighboring communication.

[0054] In voltage control of distributed power grids, virtual impedance voltage drop is calculated using dynamic virtual impedance to generate a feedforward compensation voltage reference value. By multiplying the current information in a synchronously rotating coordinate system with the dynamic virtual impedance, voltage loss is predicted and compensated in advance. This transforms the output current of the distributed power grid topology to a synchronously rotating coordinate system (dq coordinate system). This coordinate system rotates synchronously with the grid voltage vector, decomposing the three-phase AC quantities into d-axis and q-axis components. This simplifies impedance voltage drop calculations and avoids complex trigonometric function operations in the three-phase coordinate system.

[0055] Subsequently, feedforward calculations are performed in the dq coordinate system. The dynamic virtual impedance is decomposed into d-axis impedance Zd and q-axis impedance Zq. The virtual impedance voltage drop is obtained by multiplying the current and impedance to obtain the d-axis voltage drop and q-axis voltage drop. By transforming the dq-axis voltage drop back to the three-phase coordinate system, the total virtual impedance voltage drop can be obtained.

[0056] The initial voltage command is subtracted from the virtual impedance voltage drop to generate a feedforward compensation voltage reference value. For example, if the initial voltage command is 380V and the virtual impedance voltage drop is 4V, the compensated reference value is 376V. This reference value directly affects the voltage control loop, preemptively offsetting the voltage drop caused by line impedance and ensuring that the actual voltage at the node is close to the rated value.

[0057] In some embodiments, please refer to Figure 1 The process of performing hierarchical coordinated control of voltage in a distributed power grid topology, and calculating the common compensation amount of the preset virtual leader node and the local compensation amounts of each local node and neighbor node to obtain the total voltage compensation command, includes: Hierarchical and coordinated voltage control for distributed power grid topologies; Setting up a virtual leader node brings the bus voltage at the common connection point of the distributed power grid topology back to the rated value, calculates the distributed consistency correction amount, and uses it as the common compensation amount. The local voltage information of each local node and its neighboring nodes is converged to an optimal common small offset, which is used as the local compensation amount. The common compensation amount and the local compensation amount are merged into a total voltage compensation command.

[0058] This embodiment aims to solve the voltage drop problem caused by the introduction of virtual impedance and line voltage drop, and to finely adjust voltage quality. Traditional single voltage compensation will deteriorate the reactive power distribution accuracy when adjusting the common bus voltage, creating a contradiction.

[0059] Therefore, this invention adopts a hierarchical collaborative strategy: the primary control focuses on quickly restoring the common bus voltage to the rated value, while the secondary control finely adjusts each local output voltage. The two work together through the same sparse communication network to ensure the accuracy of reactive power distribution while restoring the voltage.

[0060] Primary voltage control is the restoration of the common bus voltage, which restores the voltage at the point of common coupling of the entire microgrid. Restored and stabilized at the rated value .

[0061] This is a distributed tracking and synchronization problem with a leader. We introduce a virtual leader node, whose state... The voltage is determined by the error of the common bus voltage. Each DG unit communicates its own voltage reference correction via a communication network. It coordinates with the instructions of the leader node.

[0062] 1. Global reference generation: ; in, The rated voltage reference value is equivalent to the control target, and the global reference obtained is required to be in its vicinity. These are the parameters for the PI controller.

[0063] 2. Calculation of distributed consistency correction: ; ; in, For consistency gain, For synchronization error, Let be the compensation voltage value for node i, with the superscript removed. For elements in the adjacency matrix (i and j nodes are adjacent = 1; otherwise = 0, and the same applies to aij below), This is the voltage compensation value for node i. This is the voltage compensation value for node i. Let j be the node j; Leadership weight (only for those who can directly receive) (The nodes are non-zero). This is the system's nominal voltage.

[0064] Secondary voltage regulation is a fine optimization of the local voltage. After the primary voltage control raises the overall voltage level of the system, it eliminates the local output voltage deviation of each DG caused by slight differences in line parameters, and achieves precise balance of voltage quality.

[0065] This is a leaderless distributed coordination and synchronization problem. Each DG unit converges to an optimal common small offset based solely on local voltage information with its neighbors.

[0066] Local voltage deviation: measures the actual output voltage amplitude at the local location. The deviation between the value and the local reference value after secondary control.

[0067] Distributed consistency fine-tuning calculation: Each controller, based on its local output voltage information, negotiates a small, consistent correction amount with its neighbors via communication. This makes the final output voltage of all nodes tend to be consistent.

[0068] ; ; in, For a consistent gain that is adjusted twice, its dynamic response is usually designed to be smoother than that of a single-stage compensation loop.

[0069] The compensation voltage value for node i in the secondary adjustment. The actual output voltage of node i. The actual output voltage of node j, where i is node i and j is node j; The compensation amounts of the two levels mentioned above are added together to form the compensation for the first level. Total voltage compensation command for each DG.

[0070] ; This compensation command is used to correct the original local voltage reference value, thereby obtaining the final voltage amplitude command sent to the inner loop controller. .

[0071] The distributed grid topology adopts a hierarchical collaborative voltage control method. By setting up a virtual leader node, the voltage of the common connection point bus is precisely adjusted to the rated value and a common compensation amount is generated, which effectively eliminates global voltage deviation and ensures the overall voltage stability of the grid. At the same time, each local node converges to the optimal common small offset based on the neighbor voltage information to form a local compensation amount, which can not only compensate for the voltage drop caused by local line impedance, but also avoid the conflict of compensation actions between nodes. By merging the common compensation amount and the local compensation amount into a total voltage compensation command, the overall voltage quality optimization and local voltage precision regulation are organically unified, improving the voltage support capability and anti-interference performance of the distributed power grid under complex operating conditions, and ensuring that the voltage of each node remains stable within a reasonable range. For example, in a three-node distributed power grid, the virtual leader node raises the bus voltage from 375V to 380V to generate the common compensation amount, while the local nodes fine-tune the voltage from 378V to 379.5V through neighbor information interaction to generate the local compensation amount. After merging, the total compensation command ensures that the voltage of each node remains stable within the range of 380V±0.5V.

[0072] In some embodiments, please refer to Figure 1 The voltage stabilization scheme includes modifying the initial voltage command according to the total voltage compensation command to obtain the final voltage amplitude command sent to the inner loop controller; The power allocation scheme includes a dynamic virtual impedance where the ratio of the equivalent output impedance of the distributed grid topology to its respective reactive power droop coefficient tends to converge, and the dynamic virtual impedance serves as the impedance matching condition for reactive power allocation.

[0073] In the coordinated control of distributed power grids, voltage stabilization and power allocation schemes achieve global voltage quality optimization and capacity-balanced reactive power distribution through dynamic interaction. The voltage stabilization scheme utilizes a total voltage compensation command to perform closed-loop correction on the initial voltage command. When the hierarchical coordinated control module calculates a total compensation of 0.5V, this value is superimposed on the initial voltage command of 380V to generate a final voltage amplitude command of 380.5V sent to the inner-loop controller. The inner-loop controller rapidly adjusts the inverter output voltage to ensure the actual voltage tracks this command value. For example, when line impedance causes the node voltage to drop to 378V, the final command of 380.5V will drive the inverter to generate more reactive power, thereby eliminating static voltage deviation.

[0074] The power allocation scheme relies on dynamic virtual impedance to achieve impedance matching distribution of reactive power. Dynamic virtual impedance, as a key adjustment parameter, is designed to make the ratio of the equivalent output impedance to the reactive power droop factor of each node converge. For example, if node A has an equivalent output impedance of 0.3Ω and a droop factor of 0.1, and node B has 0.6Ω and a droop factor of 0.2, with a ratio of 3 for both, then the reactive power output of both nodes under the same voltage deviation is proportional to their rated capacity. If node C has an equivalent impedance of 0.4Ω but a droop factor of 0.05, with a ratio of 8, its virtual impedance is dynamically adjusted to 0.2Ω using an accelerated consistency algorithm, making 0.4 + 0.2 = 0.6Ω, restoring the ratio of 0.4Ω to the droop factor of 0.2 to 3, thus eliminating the allocation deviation.

[0075] In some embodiments, the dynamic virtual impedance formula is: ; in, Let be the dynamic virtual impedance of the i-th DG. To fix the virtual resistance of the base, For fixed foundation virtual reactance, For correction amount, To map the correction amount to the gain factor of the actual resistance, To map the correction amount to the actual reactance, The angular frequency of the synchronously rotating coordinate system; The formula for the voltage stabilization scheme is: ; in, This is a voltage amplitude command. This is the system's nominal voltage. To output reactive power locally, Rated reactive power, The droop coefficient is... The d-axis component of the DGi output current. This represents the q-axis component of the DGi output current. For virtual resistance, Virtual reactance, This is a total voltage compensation command.

[0076] The dynamic virtual impedance of the i-th DG consists of a fixed part and a dynamic correction part. To fix the virtual resistance of the base, To fix the virtual reactance of the foundation, the fixed part can be preset based on the rated capacity of the DG and the line parameters, reducing the complexity of dynamic adjustment. For correction amount, To map the correction amount to the gain factor of the actual resistance, To map the correction amount to the actual reactance, The gain coefficient can be configured independently to adapt to the reactive power regulation requirements of different DGs. The angular frequency of the synchronous rotating coordinate system is used. In the dq coordinate system, the reactance voltage drop is expressed as a DC component, which facilitates voltage stability control.

[0077] This is a voltage amplitude command. The system's nominal voltage provides a clear target for voltage control, ensuring that all DG output voltages fluctuate around the nominal value. To output reactive power locally, Rated reactive power, The droop factor is inversely proportional to the rated capacity of the DG, enabling reactive power to be distributed proportionally to the capacity, dynamically adjusting voltage commands, and compensating for reactive power deviations. The d-axis component of the DGi output current. The q-axis component of the DGi output current is given. In the dq coordinate system, active and reactive currents independently affect the voltage amplitude and phase, simplifying the control design. For virtual resistance, Virtual reactance compensates for voltage drop due to line resistance by using the resistive component, and compensates for voltage drop due to reactance by using the reactive component, thus comprehensively improving voltage quality. The total voltage compensation command compensates for grid-level voltage deviations, avoiding over- or under-compensation in certain areas.

[0078] This invention proposes a system for adaptive virtual impedance droop control. Please refer to [link to relevant documentation]. Figure 2 ,include: The reactive power distribution unit 100 is configured to obtain the initial voltage command, equivalent output impedance and reactive power droop coefficient of the distributed power grid topology, and calculate the standardized reactive power of each local node and neighboring node based on the equivalent output impedance and reactive power droop coefficient. The dynamic adjustment unit 200 is configured to adjust the virtual impedance in the distributed power grid topology based on the accelerated consensus algorithm and the standardized reactive power generation virtual impedance of each local node and neighboring node, and to obtain the adjusted dynamic virtual impedance according to the virtual impedance adjustment amount. The feedforward compensation unit 300 is configured to calculate the virtual impedance voltage drop based on the adjusted dynamic virtual impedance feedforward, and to calculate the feedforward compensation voltage reference value based on the initial voltage command and the dynamic virtual impedance voltage drop. The hierarchical coordination unit 400 is configured to perform hierarchical coordinated control of voltage in a distributed power grid topology, and calculate the common compensation amount of the preset virtual leader node and the local compensation amount of each local node and neighbor node to obtain the total voltage compensation command. The control output unit 500 is configured to adjust the feedforward compensation voltage reference value according to the total voltage compensation command to obtain a voltage stabilization scheme, and to use the dynamic virtual impedance as a power distribution scheme.

[0079] For specific embodiments of the present invention, please refer to [link / reference]. Figure 5 , Figure 6 , Figure 7 and Figure 8 It includes an adaptive virtual impedance loop and a secondary voltage compensation module. The core is to dynamically adjust the virtual impedance through a consensus algorithm and introduce a voltage compensation term that normalizes reactive power to achieve coordinated optimization of power distribution and voltage stability.

[0080] Step 1: Establish a droop control model with virtual impedance.

[0081] Virtual impedance is a fundamental compensation mechanism in droop control, with core functions including improving power distribution accuracy, suppressing circulating current, damping oscillations, and achieving current limiting. This mechanism effectively alleviates the inherent power distribution unevenness and stability problems in the parallel operation of distributed power sources by actively reshaping the system impedance characteristics.

[0082] based on Figure 5 The dq coordinate system control framework first sets the system's rated angular frequency. Rated voltage reference value (Right now Figure 5 middle , (Base value), according to the formula , Calculate the active power droop factor for each distributed generation (DG). With reactive power droop coefficient This is used to determine the initial droop control equation. .

[0083] Let i be the angular frequency of node i. Let i be the active power. The rated active power of node i, Let i be the voltage at node i. For node i, there is no reactive power. The rated reactive power of node i; exist Figure 5 The figure shows a voltage and current dual-closed-loop control framework based on the dq coordinate system. In this framework, the three-phase currents... First, after a coordinate transformation from abc to dq, it is decomposed into d-axis current. and q-axis current The d-axis and q-axis correspond to the control channels related to active and reactive components, respectively, and each channel contains a virtual resistor. and virtual inductance These components are used to simulate line impedance characteristics to achieve control objectives such as voltage drop compensation. The d-axis and q-axis reference voltages are determined by their respective reference values. , The reference value is obtained by adding and subtracting the voltage value calculated through the virtual impedance circuit. These two reference voltages are then used to determine the final value. and This serves as the input to the voltage and current dual closed-loop control module, which also receives the actual d-axis and q-axis voltages. , By using a dual closed-loop control strategy, corresponding control signals are generated to achieve precise control of system voltage and current, ensuring stable system operation and meeting performance requirements.

[0084] Figure 6 This is the equivalent circuit diagram for adaptive virtual impedance. The equivalent output impedance of the line can then be expressed as... Set the initial virtual impedance to The virtual impedance correction value is . That is the line impedance.

[0085] Figure 6 The left side represents a voltage source, and its voltage is expressed as... This represents the amplitude and phase of the input voltage. Two impedance elements are connected in series; the first impedance element... The basic virtual impedance for the fixed part reflects the basic equivalent impedance characteristics of the distributed power source and can be preset based on the rated parameters of the power source and line characteristics. The second impedance element... This is the adaptive adjustment section, and its value changes dynamically according to the system's operating status and control requirements. Following these two virtual impedances is an actual line impedance. Complex power output from the adaptive virtual impedance section This demonstrates the role of virtual impedance in power distribution and voltage control. The entire equivalent circuit, through a series structure of virtual impedance, simulates the impact of line impedance on voltage and power. Furthermore, the adaptive virtual impedance can be adjusted according to the real-time system conditions to optimize voltage quality and achieve reasonable power distribution. Finally, it is connected to the point of common coupling (PCC), indicating the circuit's connection location and function in a distributed power grid.

[0086] Step 2: Analyze the equivalent output impedance and reactive power droop factor of the distributed generation (DG) line; Reactive power distribution in a microgrid system is achieved through reactive power-voltage droop control. To ensure that reactive power among distributed generation (DG) units is distributed according to their respective rated reactive power ratios, the reactive power droop coefficient of each DG unit needs to be set inversely proportional to its rated reactive power, i.e. (Equation 1). denoted as reactive power droop coefficient (node ​​i). Let i be the rated reactive power of node i, where i is the node.

[0087] Depend on Figure 6 And from the reactive power-voltage droop equation, we can know ( (Equation 2).

[0088] Combining equations (1) and (2), it can be seen that in order to achieve the proportional distribution of reactive power of each DG according to the rated reactive power, the following must be satisfied: In practical applications, it cannot meet the requirements. Reactive power will not be allocated according to the rated reactive power; Let i be the equivalent impedance of node i. because The equivalent impedance of the line can then be adjusted by dynamically adjusting the adaptive virtual impedance.

[0089] Step 3: Calculate the reactive power of each DG (distributed power source, which can be considered an inverter) based on the normalization of the consensus algorithm and the virtual impedance correction value. Each DG unit collects real-time reactive power through a local measurement module. Through formula Complete the reactive power normalization process; To normalize the reactive power of nodes Substitute into the consensus algorithm formula: ; Let be the integral variable, representing a specific point in time within the time interval from the initial time 0 to the current time t. The total number of DG units (of which) For communication weighting coefficients, For elements of the adjacency matrix, (For the set of neighboring nodes of the i-th DG), iteratively calculate the normalized global reactive power value. Until each DG unit They converge to the same value, at which point we have .

[0090] The formula for calculating the virtual impedance correction value is as follows: (Frequency domain integral formula) can be obtained through the formula This achieves a corrected ratio between the equivalent output impedance and the reactive power droop factor, thereby ensuring the rational distribution of reactive power. is the integral proportionality coefficient, and s is the frequency domain integral.

[0091] Step 4: Secondary voltage compensation for inverters in parallel systems; To compensate for the deviation between the output voltage and the rated voltage in droop control, a voltage compensation term is introduced into the droop equation. The expression is as follows: make Therefore, with voltage compensation added, the improved droop control equation is: .

[0092] By adjusting the integral control signal using adaptive virtual impedance, each distributed generation (DG) unit tracks this reference value, achieving precise allocation of reactive power that is strictly proportional to the unit capacity. Ultimately, the output voltage after voltage compensation allows the output voltage of each DG unit to be restored to its rated voltage. .

[0093] A parallel simulation model of two inverters was built in Simulink. A parallel system with asymmetrical line impedance was constructed and simulation tests were conducted. The simulation duration was set to 3 seconds, with a common load applied for 1-2 seconds and the load disconnected after 2 seconds. The system response characteristics (including voltage fluctuations and reactive power distribution effects) are as follows: Figure 7 and Figure 8 As shown.

[0094] exist Figure 7 During the test, when a common load was applied at 1 second, the voltage experienced a slight drop, decreasing from the initial stable value to fluctuating around the new steady-state value. At 2 seconds, the load was removed, and the voltage rapidly rose, exceeding the rated voltage (red reference line), before gradually falling back and stabilizing near the rated voltage. The system demonstrated further improved speed and stability of voltage control during sudden load changes.

[0095] exist Figure 8 In the diagram, after the load is connected, the reactive power output of both inverters Q1 and Q2 increases rapidly to meet the load's reactive power demand. After reaching steady state, the reactive power output of the two inverters is almost exactly equal. When the load is disconnected, the reactive power output of both inverters decreases rapidly, and a balance is maintained during the recovery process. This demonstrates that the two inverters can distribute reactive power evenly under ideal conditions.

[0096] This invention retains the plug-and-play advantage of traditional droop control, which is communication-independent and requires no centralized controller. It achieves global optimization through distributed collaboration, making it suitable for high-penetration renewable energy, weak grids, or islanded operation scenarios. Compared to solutions relying on centralized controllers, this design reduces communication bandwidth requirements and system complexity, while improving system anti-interference capabilities and scalability. Newly added DG units can be directly integrated into the system without requiring a redesign of the control architecture.

[0097] This invention introduces a normalized secondary voltage compensation term for reactive power into the droop control equation to directly compensate for PCC voltage drops, thereby achieving coordinated optimization of power distribution and voltage stability, which differs from existing improvement schemes that only address a single problem.

[0098] This invention employs an adaptive virtual impedance design based on a consensus algorithm. By interacting with neighboring nodes to calculate the normalized average value of global reactive power, the virtual impedance correction is dynamically adjusted, solving the problem of uneven power distribution caused by parameter mismatch and effectively suppressing circulating current. This differs from traditional fixed virtual impedance or single adaptive strategies.

[0099] Based on the same inventive concept, according to another aspect of the present invention, such as Figure 3As shown, an embodiment of the present invention also provides a computer device 30, which includes a processor 310 and a memory 320. The memory 320 stores a computer program 321 that can be run on the processor. When the processor 310 executes the program, it performs the steps of the method described above.

[0100] Based on the same inventive concept, according to another aspect of the present invention, such as Figure 4 As shown, embodiments of the present invention also provide a computer-readable storage medium 40, which stores a computer program 410 that, when executed by a processor, performs the methods described above.

[0101] Embodiments of the present invention may also include a corresponding computer device. The computer device includes a memory, at least one processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes any of the methods described above when executing the program.

[0102] The memory, as a non-volatile computer-readable storage medium, can be used to store non-volatile software programs, non-volatile computer-executable programs, and modules, such as program instructions / modules in the embodiments of this application. The processor executes various functional applications and data processing of the device by running the non-volatile software programs, instructions, and modules stored in the memory, thereby implementing the above-described method.

[0103] The memory may include a program storage area and a data storage area. The program storage area may store the operating system and applications required for at least one function; the data storage area may store data created based on the use of the device. Furthermore, the memory may include high-speed random access memory and non-volatile memory, such as at least one disk storage device, flash memory device, or other non-volatile solid-state storage device. In embodiments, the memory may optionally include memory remotely located relative to the processor, which can be connected to the local module via a network. Examples of such networks include, but are not limited to, the Internet, corporate intranets, local area networks, mobile communication networks, and combinations thereof.

[0104] Finally, it should be noted that those skilled in the art will understand that all or part of the processes in the above embodiments can be implemented by a computer program instructing related hardware. The program can be stored in a computer-readable storage medium, and when executed, it can include the processes of the embodiments of the methods described above. The storage medium for the program can be a magnetic disk, optical disk, read-only memory (ROM), or random access memory (RAM), etc. The above computer program embodiments can achieve the same or similar effects as any of the corresponding foregoing method embodiments.

[0105] Those skilled in the art will also understand that the various exemplary logic blocks, modules, circuits, and algorithm steps described in conjunction with the disclosure herein can be implemented as electronic hardware, computer software, or a combination of both. To clearly illustrate this interchangeability between hardware and software, the functionality of various illustrative components, blocks, modules, circuits, and steps has been generally described. Whether this functionality is implemented as software or as hardware depends on the specific application and the design constraints imposed on the system as a whole. Those skilled in the art can implement the functionality in various ways for each specific application, but such implementation decisions should not be construed as departing from the scope of the embodiments disclosed herein.

[0106] The above are exemplary embodiments disclosed in this invention. However, it should be noted that various changes and modifications can be made without departing from the scope of the embodiments of this invention as defined by the claims. The functions, steps, and / or actions of the methods according to the disclosed embodiments described herein do not need to be performed in any particular order. The sequence numbers of the disclosed embodiments of this invention are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments. Furthermore, although the elements disclosed in the embodiments of this invention may be described or claimed individually, they may be understood as multiple unless explicitly limited to a singular number.

[0107] It should be understood that, as used herein, the singular form “a” is intended to include the plural form as well, unless the context clearly supports an exception. It should also be understood that, as used herein, “and / or” refers to any and all possible combinations of one or more of the associated listed items.

[0108] Those skilled in the art should understand that the discussion of any of the above embodiments is merely exemplary and is not intended to imply that the scope of the invention (including the claims) is limited to these examples. Within the framework of the invention, technical features of the above embodiments or different embodiments can be combined, and many other variations of different aspects of the invention exist, which are not provided in the details for the sake of brevity. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the invention should be included within the protection scope of the invention.

Claims

1. A method for adaptive virtual impedance droop control, characterized in that, include: The initial voltage command, equivalent output impedance, and reactive power droop coefficient of the distributed power grid topology are obtained, and the standardized reactive power of each local node and neighboring node is calculated based on the equivalent output impedance and reactive power droop coefficient. Based on the accelerated consensus algorithm and the correction amount of the standardized reactive power generated by each local node and neighbor node, the virtual impedance in the distributed power grid topology is adjusted according to the correction amount of the virtual impedance to obtain the adjusted dynamic virtual impedance. The virtual impedance voltage drop is calculated based on the adjusted dynamic virtual impedance feedforward, and the feedforward compensation voltage reference value is calculated based on the initial voltage command and the dynamic virtual impedance voltage drop. The voltage of the distributed power grid topology is controlled in a hierarchical and coordinated manner. The total voltage compensation command is obtained by calculating the common compensation amount of the preset virtual leader node and the local compensation amount of each local node and neighbor node. The feedforward compensation voltage reference value is adjusted according to the total voltage compensation command to obtain a voltage stabilization scheme, and the dynamic virtual impedance is used as the power distribution scheme.

2. The method for adaptive virtual impedance droop control according to claim 1, characterized in that, The process of calculating the standardized reactive power of each local node and neighboring node based on the equivalent output impedance and reactive power droop factor includes: Configure distributed computing nodes for distributed power grid topologies; Calculate the normalized reactive power of this node and the normalized reactive power of neighboring nodes based on the equivalent output impedance and reactive power droop factor. The standardized reactive power refers to the relative size of the actual output reactive power to its rated reactive power under the current droop coefficient.

3. The method for adaptive virtual impedance droop control according to claim 2, characterized in that, The process of adjusting the virtual impedance in the distributed grid topology based on the correction amount of the virtual impedance generated by the accelerated consensus algorithm and the standardized reactive power of each local node and neighboring nodes, to obtain the adjusted dynamic virtual impedance, includes: The consensus error is calculated by averaging the normalized reactive power of the local node and the normalized reactive power of the neighboring nodes based on the accelerated consensus algorithm. The consistency error is passed through a proportional-integral regulator to generate a correction amount for the virtual impedance; The virtual impedance in the distributed power grid topology is dynamically adjusted based on the correction amount to obtain the adjusted dynamic virtual impedance.

4. The method for adaptive virtual impedance droop control according to claim 1, characterized in that, The process of calculating the virtual impedance voltage drop based on the dynamic virtual impedance, and calculating the feedforward compensation voltage reference value based on the initial voltage command and the virtual impedance voltage drop, includes: In a synchronous rotating coordinate system, the virtual impedance voltage drop is obtained by feedforward calculation using the sum of the output current of the distributed power grid topology and the dynamic virtual impedance. The initial voltage command minus the virtual impedance voltage drop yields the feedforward compensation voltage reference value.

5. The method for adaptive virtual impedance droop control according to claim 1, characterized in that, The process of performing hierarchical coordinated control of voltage in a distributed power grid topology, and calculating the common compensation amount of the preset virtual leader node and the local compensation amounts of each local node and neighbor node to obtain the total voltage compensation command, includes: Hierarchical and coordinated voltage control for distributed power grid topologies; Setting up a virtual leader node brings the bus voltage at the common connection point of the distributed power grid topology back to the rated value, calculates the distributed consistency correction amount, and uses it as the common compensation amount. The local voltage information of each local node and its neighboring nodes is converged to an optimal common small offset, which is used as the local compensation amount. The common compensation amount and the local compensation amount are merged into a total voltage compensation command.

6. The method for adaptive virtual impedance droop control according to claim 1, characterized in that, The voltage stabilization scheme includes correcting the initial voltage command according to the total voltage compensation command to obtain the final voltage amplitude command sent to the inner loop controller; The power allocation scheme includes a dynamic virtual impedance where the ratio of the equivalent output impedance of the distributed grid topology to its respective reactive power droop coefficient tends to converge, and the dynamic virtual impedance serves as the impedance matching condition for reactive power allocation.

7. The method for adaptive virtual impedance droop control according to claim 1, characterized in that, The formula for the dynamic virtual impedance is: ； in, Let be the dynamic virtual impedance of the i-th DG. To fix the virtual resistance of the base, For fixed foundation virtual reactance, For correction amount, To map the correction amount to the gain factor of the actual resistance, To map the correction amount to the actual reactance, The angular frequency of the synchronously rotating coordinate system; The formula for the voltage stabilization scheme is: ； in, This is a voltage amplitude command. This is the system's nominal voltage. To output reactive power locally, Rated reactive power, The droop coefficient is... The d-axis component of the DGi output current. This represents the q-axis component of the DGi output current. For virtual resistance, Virtual reactance, This is a total voltage compensation command.

8. A system for adaptive virtual impedance droop control, characterized in that, include: The reactive power distribution unit is configured to obtain the initial voltage command, equivalent output impedance and reactive power droop coefficient of the distributed power grid topology, and calculate the standardized reactive power of each local node and neighboring node based on the equivalent output impedance and reactive power droop coefficient. The dynamic adjustment unit is configured to adjust the virtual impedance in the distributed power grid topology based on the accelerated consensus algorithm and the standardized reactive power generation virtual impedance of each local node and neighboring node, and to obtain the adjusted dynamic virtual impedance according to the virtual impedance adjustment amount. The feedforward compensation unit is configured to calculate the virtual impedance voltage drop based on the adjusted dynamic virtual impedance feedforward, and to calculate the feedforward compensation voltage reference value based on the initial voltage command and the dynamic virtual impedance voltage drop. The hierarchical coordination unit is configured to perform hierarchical coordinated control of voltage in a distributed power grid topology, and calculates the common compensation amount of the preset virtual leader node and the local compensation amount of each local node and neighbor node to obtain the total voltage compensation command. The control output unit is configured to adjust the feedforward compensation voltage reference value according to the total voltage compensation command to obtain a voltage stabilization scheme, and to use the dynamic virtual impedance as a power distribution scheme.

9. A computer device, comprising: At least one processor; And a memory storing a computer program executable on the processor, characterized in that, when the processor executes the program, it performs the steps of the method for adaptive virtual impedance droop control as described in any one of claims 1 to 7.

10. A computer-readable storage medium storing a computer program, characterized in that, When the computer program is executed by the processor, it performs the steps of the method for adaptive virtual impedance droop control as described in any one of claims 1 to 7.

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