Power distribution network cluster voltage control method and system based on variable weight consistency

Abstract

The invention discloses a power distribution network cluster voltage control method based on variable weight consistency, and discloses a system with the power distribution network cluster voltage control method based on variable weight consistency and a medium. According to the power distribution network cluster voltage control method based on the variable weight consistency, sufficient power support can still be provided when the voltage fluctuation is relatively large or is close to an overvoltage / undervoltage limit through a mode of improving weight setting in an algorithm and adding a dominant node standard voltage deviation item; the node cluster voltage of the power distribution network is quickly converged to a standard range.

Description

Technical Field

[0001] The present invention relates to the technical field of dynamic uncertainty measurement, and particularly to a distribution network cluster voltage control method and system based on variable-weight consistency. Background Art

[0002] With the transformation of the energy structure and the wide application of renewable energy, the power system is changing from the traditional large-scale centralized mode to a network containing a large number of distributed power sources. Especially at the distribution network level, the rapid development of new loads such as distributed generation, energy storage devices, and electric vehicles has brought new challenges and opportunities to the voltage control of the distribution network. The voltage control devices in the distribution network (such as reactive power compensation devices, etc.) are usually designed for the traditional power flow direction. The access of distributed power sources has broken the law of the traditional power flow, resulting in changes in the working mode and coordination mechanism of the voltage control devices. New control strategies, optimization algorithms, etc. are needed to adapt to the new power flow and ensure the effectiveness and stability of voltage control.

[0003] In the prior art, although there is already distributed voltage control based on the consensus algorithm to achieve the global optimal voltage distribution through multi-node cooperation in the new distribution network, it has advantages such as real-time performance, robustness, and easy scalability. Through the information interaction of adjacent nodes, it can quickly respond to voltage fluctuations without relying on a centralized controller, reduce reactive power loss, and improve the voltage stability and adaptability of the system. At the same time, the consensus algorithm reduces the need for long-distance communication, making the control system more efficient, flexible, and reliable when a large number of distributed power sources are connected.

[0004] However, the application of the existing consensus algorithm in the distributed voltage control of the distribution network has certain limitations. For example, the variable setting is difficult to adapt to the complex actual operating environment, and the design of the interaction rules between nodes is relatively idealized, making it difficult to fully cope with the dynamic changes in the actual scenario. These problems may lead to the algorithm being difficult to converge or producing suboptimal control effects in practical applications. Therefore, it is necessary to further improve in terms of parameter optimization, adaptability of the interaction mechanism, and robustness to enhance its effectiveness and practicality in the new distribution network. Summary of the Invention

[0005] The present invention aims to solve at least one of the technical problems existing in the prior art. For this purpose, the present invention proposes a distribution network cluster voltage control method based on variable-weight consistency. By improving the weight setting in the algorithm and adding the standard voltage deviation term of the dominant node, it can still provide sufficient power support when the voltage fluctuation is large or close to the overvoltage / undervoltage limit, and realize the rapid convergence of the distribution network node cluster voltage to the standard range.

[0006] The present invention also proposes a system having the above-mentioned distribution network cluster voltage control method based on variable-weight consistency.

[0007] A method for voltage control of a distribution network cluster based on variable-weight consistency according to an embodiment of the first aspect of the present invention is characterized by including the following steps:

[0008] Select an adjustment cluster, calculate the remaining adjustment capacity of each node in the adjustment cluster, and determine the adjustment capacity limit of each node according to the remaining adjustment capacity of each node;

[0009] Detect the actual voltage of each node in the adjustment cluster, and determine whether there are voltage-limit-exceeding nodes according to the actual voltage of each node;

[0010] If there are voltage-limit-exceeding nodes, calculate the voltage-limit-exceeding degree of each node;

[0011] Dynamically calculate the consistency parameter of each node according to the absolute value of the voltage-limit-exceeding degree of each node and the direction flag quantity;

[0012] Through information interaction between nodes, update the consistency parameter of each node, and generate a reactive power output command value for each node based on the updated consistency parameter of each node and the adjustment capacity limit of each node;

[0013] Control the voltage and power of each node based on the reactive power output command value to adjust the voltage of each node until the voltages of all nodes converge to the normal range or the number of times of calculating the voltage-limit-exceeding degree reaches a preset maximum number of calculations.

[0014] The method for voltage control of a distribution network cluster based on variable-weight consistency according to an embodiment of the present invention has at least the following beneficial effects: The method for voltage control of a distribution network cluster based on variable-weight consistency provided by the present invention can still provide sufficient power support when the voltage fluctuates greatly or is close to the overvoltage / undervoltage limit by improving the weight setting in the algorithm and adding the standard voltage deviation term of the leading node, realizing the rapid convergence of the voltages of the distribution network node clusters to the standard range, being able to meet the requirements of different application scenarios, and increasing the practicability.

[0015] According to some embodiments of the present invention, the nodes in the adjustment cluster include leading nodes, and the selection process of the leading nodes needs to meet at least one of the following conditions:

[0016] The number of adjacent nodes of the leading node exceeds a preset threshold;

[0017] The remaining adjustment capacity of the leading node is greater than the average adjustment capacity of other nodes in the adjustment cluster except the leading node;

[0018] The adjustment sensitivity of the leading node is higher than the average sensitivity of other nodes in the adjustment cluster except the leading node.

[0019] According to some embodiments of the present invention, in the step of dynamically calculating the consistency parameter of each node according to the absolute value of the voltage over-limit of each node and the direction flag quantity, the consistency parameter λ i,t The dynamic calculation rule is:

[0020] When the absolute value of the voltage over-limit is greater than the first threshold, the consistency parameter is calculated according to the formula λ i,1 = α × deviU i,1 Calculate;

[0021] When the absolute value of the voltage over-limit is less than or equal to the first threshold, the consistency parameter is calculated according to the formula λ i,1 = β × signdeviU i,1 Calculate;

[0022] Among them, λ i,t represents the consistency parameter, t represents the t-th calculation; α and β are preset consistency parameter adjustment weight coefficients; deviU i,1 is the voltage over-limit of node I; signdeviU i,t is the over-limit direction flag quantity.

[0023] According to some embodiments of the present invention, in non-primary calculations, if the over-limit direction of the current time is the same as the over-limit direction of the previous time of the current time and the absolute value of the voltage over-limit is less than the second threshold, the consistency parameter inherits the calculation result of the previous time; if the over-limit direction of the current time is opposite to the over-limit direction of the previous time of the current time, the consistency parameter is calculated according to the product of 50% of the absolute value of the voltage over-limit of the previous time of the current time and the direction flag quantity of the current time.

[0024] According to some embodiments of the present invention, in the step of updating the consistency parameter of each node through information interaction between nodes, and generating the reactive power output command value of each node based on the updated consistency parameter of each node and the adjustment capacity limit of each node, and controlling the voltage and power of each node based on the reactive power output command value, the weight η i,j of the information interaction between nodes is dynamically allocated according to the communication relationship identifier, and the calculation formula is:

[0025]

[0026] Among them, e i,l is the communication relationship identifier between node i and node l. If communication can be achieved between node i and node l, then e i,l = 1. If communication cannot be achieved, then e i,l = 0. If communication is possible, it is 1, otherwise it is 0.

[0027] According to some embodiments of the present invention, in the step of updating the consistency parameters of each node through information interaction between nodes, adjusting each node in the cluster includes a leading node and non-leading nodes. The interaction calculation of the leading node adds a standard voltage deviation term. The consistency parameter update formula of the leading node is:

[0028]

[0029] where t is the number of times of calculating the consistency parameter after the cluster voltage exceeds the limit, ε is the deviation adjustment weight, and gapU i,t is the standard voltage deviation value, and the standard voltage deviation value is the difference between the actual voltage of the leading node at time t + 1 and the standard voltage, that is, gapU i,t = U i,t - 1.

[0030] According to some embodiments of the present invention, the step of adjusting the voltage of each node until the voltages of all nodes converge to the normal range or the number of times of calculating the voltage over-limit degree reaches the preset maximum number of calculations includes:

[0031] When the per-unit values of the voltages of all nodes are within the non-overlimit range, it indicates whether the voltage converges to the normal range and reaches the maximum number of calculations, including: when the number of adjustment times reaches the preset maximum number of calculations t max , it indicates that the maximum number of calculations is reached.

[0032] According to some embodiments of the present invention, in the step of generating the reactive power output command value of each node based on the updated consistency parameters of each node and the adjustment capacity limit of each node, the calculation rule of the reactive power output command value Q refi,t+1 is:

[0033] Q refi,t+1 = λ i,t+1 × Q ima

[0034] where Q imax is the maximum reactive power adjustment capacity of node i.

[0035] According to the second aspect of the embodiments of the present invention, a distribution network cluster voltage control system based on variable-weight consistency is characterized by including:

[0036] A node selection module, which can select an adjustment cluster and select a leading node from each node of the adjustment cluster, calculate the remaining adjustment capacity of each node in the adjustment cluster, and determine the adjustment capacity limit of each node according to the remaining adjustment capacity of each node;

[0037] A node voltage over-limit judgment module, which can detect the actual voltage of each node in the adjustment cluster and judge whether there is a voltage over-limit node according to the actual voltage of each node;

[0038] A voltage over - limit calculation module, which can calculate the voltage over - limit degree of each node when there are voltage over - limit nodes;

[0039] A consistency parameter calculation module, which can dynamically calculate the consistency parameter of each node according to the absolute value of the voltage over - limit degree of each node and the direction flag quantity;

[0040] A parameter update module, which can update the consistency parameter of each node through information interaction between nodes, and generate a reactive power output command value for each node based on the updated consistency parameter of each node and the remaining regulation capacity of each node;

[0041] A power control module, which can control the voltage and power of each node based on the reactive power output command value;

[0042] A result judgment module, which can adjust the voltage of each node until the voltages of all nodes converge to the normal range or the number of times of calculating the voltage over - limit degree reaches the preset maximum calculation times.

[0043] According to some embodiments of the present invention, the selection conditions of the leading node in the node selection module include at least one of the following:

[0044] The number of adjacent nodes of the leading node exceeds a preset threshold;

[0045] The remaining regulation capacity of the leading node is greater than the average regulation capacity of other nodes in the regulation cluster except the leading node;

[0046] The regulation sensitivity of the leading node is higher than the average sensitivity of other nodes in the regulation cluster except the leading node.

[0047] According to some embodiments of the present invention, in the consistency parameter calculation module, the dynamic calculation rule of the consistency parameter λ i,t is as follows:

[0048] When the absolute value of the voltage over - limit degree is greater than the first threshold, the consistency parameter is calculated according to the formula λ i,1 =α×deviU i,1 ;

[0049] When the absolute value of the voltage over - limit degree is less than or equal to the first threshold, the consistency parameter is calculated according to the formula λ i,1 =β×signdeviU i,1 ;

[0050] where λ i,t represents the consistency parameter, t represents the t - th calculation, here t = 1; α and β are preset consistency parameter adjustment weight coefficients; deviU i,1 is the voltage over - limit degree of node i; signdeviU i,tIs the over-limit direction flag quantity.

[0051] According to some embodiments of the present invention, in non-primary calculations, if the over-limit direction of the current time is the same as the over-limit direction of the previous time of the current time and the absolute value of the voltage over-limit degree is less than the second threshold, the consistency parameter inherits the calculation result of the previous time; if the over-limit direction of the current time is opposite to the over-limit direction of the previous time of the current time, the consistency parameter is calculated according to the product of 50% of the absolute value of the voltage over-limit degree of the previous time of the current time and the direction flag quantity of the current time.

[0052] According to some embodiments of the present invention, the weight η of the information interaction between nodes in the parameter update module i,j Is dynamically allocated according to the communication relationship identifier, and the calculation formula is:

[0053]

[0054] Wherein, e i,l Is the communication relationship identifier between node u and node l. If communication can be achieved between node i and node l, then e i,l = 1. If communication cannot be achieved, then e i,l = 0. If communication is possible, it is 1, otherwise it is 0.

[0055] According to some embodiments of the present invention, in the parameter update module, each node in the cluster includes a leading node and a non-leading node. The interactive calculation of the leading node adds a standard voltage deviation term, and the consistency parameter update formula of the leading node is:

[0056]

[0057] Wherein, t is the number of times of consistency parameter calculation after the cluster voltage exceeds the limit, ε is the deviation adjustment weight, and gapU i,t Is the standard voltage deviation value, and the standard voltage deviation value is the difference between the actual voltage of the leading node at time t + 1 and the standard voltage, that is, gapU i,t = U i,t -1.

[0058] According to some embodiments of the present invention, the convergence conditions in the result judgment module include:

[0059] When the per-unit values of the voltages of all nodes are within the non-over-limit range, it represents whether the voltage converges to the normal range.

[0060] Reaching the maximum number of calculations, including: when the number of adjustment times reaches the preset maximum number of calculations t max , it represents reaching the maximum number of calculations.

[0061] According to some embodiments of the present invention, in the power control module, the reactive power output command value Qrefi,t+1 The calculation rule is as follows:

[0062] Q re fi ,t+1 = λ i,t+1 ×Q ima

[0063] where Q ima is the maximum reactive power regulation capacity of node i.

[0064] According to a computer-readable storage medium of an embodiment of the third aspect of the present invention, the medium stores computer-executable instructions for executing the above-mentioned distribution network cluster voltage control method based on variable weight consistency.

[0065] The additional aspects and advantages of the present invention will be partially given in the following description, partially become obvious from the following description, or be understood through the practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0066] The above and / or additional aspects and advantages of the present invention will become obvious and easy to understand from the description of the embodiments in conjunction with the following drawings, wherein:

[0067] Figure 1 is a schematic diagram of the steps of the distribution network cluster voltage control method based on variable weight consistency according to an embodiment of the present invention;

[0068] Figure 2 is a flow chart of the consistency parameter setting in the distribution network cluster voltage control method based on variable weight consistency provided by an embodiment of the present invention;

[0069] Figure 3 is a flow chart of the distributed information interaction calculation in the distribution network cluster voltage control method based on variable weight consistency provided by an embodiment of the present invention;

[0070] Figure 4 is a schematic diagram of the cluster voltage change when the distribution network cluster voltage control method based on variable weight consistency provided by an embodiment of the present invention is applied to the modified IEEE14 node distribution system instance;

[0071] Figure 5 is a schematic diagram of the cluster voltage change when Strategy 1 of the distribution network cluster voltage control method based on variable weight consistency provided by an embodiment of the present invention is applied to the modified IEEE14 node distribution system instance;

[0072] Figure 6 is a schematic diagram of the cluster voltage change when the comparison strategy 2 of the distribution network cluster voltage control method based on variable weight consistency provided by an embodiment of the present invention is applied to the modified IEEE14 node distribution system instance

[0073] Figure 7 This is the structural block diagram of the distribution network cluster voltage control system based on variable weight consistency provided by the embodiments of the present invention. Specific embodiments

[0074] The embodiments of the present invention will be described in detail below. Examples of the embodiments are shown in the accompanying drawings, where the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention and should not be construed as a limitation of the present invention.

[0075] In the description of the present invention, it should be understood that the orientation descriptions, such as up, down, front, back, left, right, etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation of the present invention.

[0076] In the description of the present invention, the meaning of several is one or more, the meaning of multiple is more than two, and understandings such as greater than, less than, exceeding, etc. do not include the present number, and understandings such as above, below, within, etc. include the present number. If there is a description of first and second, it is only for the purpose of distinguishing technical features and should not be construed as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features or implicitly indicating the sequence relationship of the indicated technical features.

[0077] In the description of the present invention, unless otherwise clearly defined, words such as setting, installing, connecting, etc. should be understood in a broad sense, and those skilled in the art can reasonably determine the specific meanings of the above words in the present invention in combination with the specific content of the technical solution.

[0078] Embodiment 1

[0079] In order to address the deficiencies in the existing distribution network voltage control technology, the embodiments of the present application provide a distribution network cluster voltage control method based on variable weight consistency. By improving the weight setting in the algorithm and adding the standard voltage deviation term of the dominant node, sufficient power support can still be provided when the voltage fluctuates greatly or approaches the overvoltage / undervoltage limit, and the voltage of the distribution network node cluster can be quickly converged to the standard range.

[0080] This method at least includes the following steps:

[0081] Step S1: Select the adjustment cluster and select the dominant node from each node of the subordinate adjustment cluster, calculate the remaining adjustment capacity of each node in the adjustment cluster, and determine the adjustment capacity limit of each node according to the remaining adjustment capacity of each node.

[0082] According to factors such as the adjustment requirements and the actual electrical distance of the distribution network, select some nodes as the adjustment cluster to avoid too many nodes participating in the adjustment, which may affect the adjustment efficiency; select the nodes with more adjacent nodes, larger adjustment capacity, and higher adjustment sensitivity as the leading nodes to accelerate the voltage convergence speed.

[0083] Considering that it is difficult to achieve voltage control by active power reduction in the actual distribution network, therefore, the present invention uses reactive power adjustment as a means to eliminate voltage over-limit. Calculate the remaining adjustment capacity of the selected adjustment cluster. Taking node i as an example, considering the power factor limit and active power reduction limit, the maximum reactive power adjustment capacity of the node ±Q can be obtained max (assuming that reactive power can be adjusted bidirectionally), and record the current reactive power output of the node as Q i .

[0084] Step S2: Detect the actual voltage of each node in the adjustment cluster, and judge whether there are voltage over-limit nodes according to the actual voltage of each node.

[0085] Detect the actual voltage of each node in the adjustment cluster, calculate the per-unit value according to the reference voltage of the distribution network, and record it as U i ; Judge whether it is over-limit (if the per-unit value of the node voltage exceeds 1.05 p.u. or is lower than 0.95 p.u., it is regarded as voltage over-limit). If at least one node voltage in the cluster is over-limit, execute step 3; if the voltages of all nodes in the cluster are not over-limit, then continue to execute step 2.

[0086] Step S3: If there are voltage over-limit nodes, calculate the voltage over-limit degree of each node.

[0087] Define the voltage over-limit degree deviU of the node. The voltage over-limit degree of each node is calculated according to the following formula:

[0088]

[0089] Step S4: Dynamically calculate the consistency parameters of each node according to the absolute value of the voltage over-limit degree of each node and the direction flag quantity. Specifically, it includes:

[0090] Step 4.1 Define the number of times of calculating the consistency parameter after the cluster voltage is over-limit as t. Taking node i as an example, this calculation is based on the node voltage over-limit degree deviU of node i at the t-th time i,t , define the absolute voltage over-limit degree absdeviU i,t , and calculate according to the following formula: absdeviU i,t = |deviU i,t |.

[0091] Step 4.2 Define the over-limit direction flag quantity signdeviU of node voltage i at the t-th timei，t , calculated according to the following formula:

[0092]

[0093] Step 4.3 Determine whether this calculation is the first calculation after over - limit. If so, set t = 1 and define the consistency parameter λ according to the following rules i,1 :

[0094]

[0095] where α and β are the adjustment weights of the consistency parameter, and the present invention will give suggested values in specific embodiments.

[0096] Step 4.4 Define the absolute value of the consistency parameter absλ = |λ|. If this calculation of the consistency parameter is not the first calculation after over - limit, update the calculation times t and define the consistency parameter λ according to the following rules i，t :

[0097]

[0098] Step S5. Through information interaction between nodes, update the consistency parameters of each node, and generate the reactive power output command values of each node based on the updated consistency parameters of each node and the remaining adjustment capacity of each node.

[0099] Step 5.1 The present invention sets that the communication lines between communicable nodes can all achieve two - way communication. Taking node i in the cluster as an example, if the number of its cluster nodes is defined as n, the interaction variable between it and node l in the cluster is set as:

[0100]

[0101] where e i,l is the communication relationship identifier between node i and node l. If communication can be achieved between node i and node l, then e i,l = 1; if communication cannot be achieved, then e i,l = 0; in particular, set e i,i = 1. is the sum of the communication relationship identifiers between node i and all nodes in the cluster (including node i).

[0102] Step 5.2 If node i is the set leading node, perform interaction calculations and update the consistency parameter according to the following rules:

[0103]

[0104] where ε is the voltage deviation adjustment weight, and the present invention will give suggested values in specific embodiments. gapU i,tis the standard voltage deviation value. To accelerate the voltage control speed, this voltage deviation value is set as the difference between the voltage of the dominant node at this moment and the standard voltage, that is, gapU i,t = U i,t - 1

[0105] Step 5.3 If node i is not the set dominant node, the standard voltage deviation is not considered in the calculation, and the interaction calculation is performed according to the following rules to update the consistency parameter:

[0106]

[0107] Step 5.4 Calculate the reactive power command value Q of this node according to the updated consistency parameter refi,t+1 , and the calculation rule is as follows:

[0108] Q refi,t+1 = λ i,t+1 × Q imax (6)

[0109] Step S6. Control the voltage and power of each node based on the reactive power output command value

[0110] Specifically, it includes:

[0111] Step 6.1 If the reactive power command value Q re,t+1 exceeds the upper limit value +Q of the reactive power regulation of node i imax , or is lower than the lower limit value -Q imax , then node i outputs reactive power according to the power limit value ±Q imax for voltage control

[0112] Step 6.2 If the reactive power command value Q refi,t+1 is between the reactive power regulation limit values ±Q of node i imax , then node i outputs reactive power according to the command value Q refi,t+1 for voltage control

[0113] Step S7. Adjust the voltage of each node until the voltages of all nodes converge to the normal range or the number of times of calculating the voltage over-limit reaches the preset maximum number of calculations. Specifically, it includes

[0114] Step 7.1 Set the maximum number of calculations t max , if the number of calculations t > t max , then end the voltage regulation process; if t < t max , then continue to execute Step 7.2

[0115] Step 7.1 Execute Step 2 to perform cluster voltage detection. If the voltages of all nodes in the cluster do not exceed the limit, then end the regulation process; if there are over-limit nodes in the cluster, then continue to execute Steps 3 to 6

[0116] Example Two

[0117] Another embodiment of this application provides a multi-node voltage control method for a distribution system, which is illustrated by a modified IEEE 14-node distribution system.

[0118] Set the power reference value to 100 MWA. The branch impedances are shown in Table 1, the node loads and initial voltages are shown in Table 2, and the generator output data connected are as Figure 3 shown.

[0119] Table 1 Branch Connections and Their Impedances

[0120]

[0121] Table 2 Node Loads and Initial Voltages

[0122]

[0123] Table 3 Generator Output Data

[0124]

[0125] Select nodes 11 - 14 as the regulation group, and set node 14 as the leading node. At a certain moment, the active load of node 11 increases, and the active loads of nodes 12, 13, and 14 decrease. The load change situation and the node voltages after the change are shown in Table 4 (in the table, an increase in active load is positive, and a decrease in active load is negative).

[0126] Table 4 Load and Voltage Change Situations of Nodes 11 - 14

[0127]

[0128] Set the maximum available reactive power regulation capacity of each node from nodes 11 - 14 to 10% of the total capacity. The adjustable capacity and the connection situation of the communication lines between nodes are shown in Table 5.

[0129] Table 5 Adjustable Capacities of Nodes 11 - 14 and Communication Lines between Nodes

[0130]

[0131] The program is compiled using Matlab software to verify the voltage control effect of the present invention. The voltage regulation is carried out by using the distribution network cluster voltage control method based on variable-weight consistency proposed by the present invention. First, enter step 2 for voltage detection. As can be seen from Table 4, there are voltage over-limit nodes in the cluster. Enter step 3 to calculate the voltage over-limit degree, and the voltage over-limit degrees of nodes 11 - 14 are obtained as: -0.0659, -0.0229, -0.0363, -0.0559 (reserved to 4 decimal places).

[0132] After obtaining the voltage over-limit degree, enter step 4 to calculate the consistency parameter. In this embodiment, the adjustment weight of the consistency parameter is set according to the following rules: α = 20, β = 0.5; Since this calculation is the initial calculation after over-limit, according to step 4.3, the initial values of the consistency parameters of nodes 11 - 14 are: -1.3187, -0.4582, -0.7255, -1.1184 (reserved to 4 decimal places).

[0133] Enter step 5. According to the calculation in step 5.1, the interaction variables between nodes are shown in Table 6.

[0134] Table 6 Interaction variables between nodes of the selected adjustment group

[0135]

[0136] In this embodiment, the voltage deviation adjustment weight ε = 0.5 is set. After the calculations in steps 5.2 to 5.4, the reactive power command values of nodes 11 - 14 are respectively: -1.5824, -0.5919, -1.5347, -2.9246 (unit: MVar, reserved to 4 decimal places).

[0137] Enter step 6 to judge whether the reactive power command value exceeds the limit, and adjust the reactive power output according to the adjustment rules in steps 6.1 and 6.2. The reactive power output values of nodes 11 - 14 are respectively: -1.2000, -0.5919, -1.5347, -2.9246 (unit: MVar, reserved to 4 decimal places).

[0138] Enter step 7.1, and set the maximum number of calculations t max = 200. At this time, t = 1, which satisfies t < t max , execute step 7.2 to perform cluster voltage detection. At this time, the per-unit values of the voltages of nodes 11 - 14 are respectively: 0.8971, 0.9410, 0.9290, 0.9115 (reserved to 4 decimal places). There are still over-limit nodes in the cluster, and continue to execute steps 3 - 6.

[0139] After 21 times of regulation, the voltages of all nodes in the cluster converge to the normal range (between 0.95 p.u. and 1.05 p.u.). The variation of the node voltages during the regulation process is as shown in Figure 4 shown. At the end of the regulation process, the per-unit values of the voltages of nodes 11 - 14 are: 0.9504, 0.9904, 0.9827, 0.9728 (reserved to 4 decimal places).

[0140] Example 3

[0141] Based on a part of Example 1, a variable-weight consensus-based distribution network cluster voltage control method is proposed for comparison with the existing fixed-weight consensus algorithm voltage regulation strategy.

[0142] Comparison strategy 1: The fixed-weight consensus algorithm voltage control strategy without setting the standard voltage deviation term of the dominant node. Its consensus parameter is set according to the following rule: λ i,t = α × deviU i,t , where the values and calculation methods of α and deviU i,t are the same as those of the present invention, and the value of λ i,t does not distinguish whether it is the first calculation after over-limit. This strategy does not select a dominant node and does not add the standard voltage deviation term. Its node interaction rule is set according to the following rule:

[0143] The settings of each parameter in the formula are the same as those of the present invention.

[0144] The variation of the node voltages when applying comparison strategy 1 for voltage regulation is as shown in Figure 5 shown. It can be seen that after 200 times of regulation, the node voltages of strategy 1 still do not converge to the normal range, exceeding the maximum calculation times t max = 200 set in Part 7, and the regulation is unsuccessful.

[0145] Comparison strategy 2: The fixed-weight consensus algorithm voltage control strategy with the standard voltage deviation term of the dominant node set. Its consensus parameter setting rule is the same as that of comparison strategy 1; this strategy selects a dominant node (the same as the dominant node selected in the specific embodiment of the present invention in Part 7), adds the standard voltage deviation term, that is, its node interaction rule is the same as that of the present invention.

[0146] The variation of the node voltages when applying comparison strategy 2 for voltage regulation is as shown in Figure 6 shown. It can be seen from the figure that after 42 times of regulation, the voltage converges to the normal range. Compared with the regulation strategy proposed by the present invention, the calculation speed is slower and the regulation efficiency is lower.

[0147] By comparing with strategy 1 and strategy 2, the beneficial effects of the present invention are as follows:

[0148] 1. The present invention realizes the dynamic tracking and progressive convergence of the dominant node voltage to the target standard voltage value by introducing the dominant node voltage deviation term. It effectively enhances the voltage fluctuation response ability, makes the voltage control process faster and more accurately convergent, and ensures that the system maintains good voltage stability under various load and disturbance conditions.

[0149] 2. The present invention proposes a setting method based on variable-weight consistency parameters. This method dynamically adjusts the setting of consistency parameters according to the voltage deviation value, and can still provide sufficient power support especially when the voltage fluctuation is large or close to the over-voltage / under-voltage limit, significantly accelerating the voltage convergence speed, minimizing the potential risks caused by voltage instability or slow control response, and improving the operation efficiency and reliability of the distribution network.

[0150] Embodiment Four

[0151] Another embodiment of the present application provides a distribution network cluster voltage control system based on variable-weight consistency, as Figure 7 shown. This system 70 includes:

[0152] A node selection module 701, capable of selecting an adjustment cluster and a dominant node, and calculating the remaining adjustment capacity of the nodes;

[0153] A node voltage over-limit judgment module 702, capable of detecting the actual voltage of each node in the adjustment cluster and judging whether there is a voltage over-limit node;

[0154] A voltage over-limit degree calculation module 703, capable of calculating the voltage over-limit degree of each node if there is a voltage over-limit node;

[0155] A consistency parameter calculation module 704, capable of dynamically calculating consistency parameters according to the absolute value of the voltage over-limit degree and the direction flag quantity;

[0156] A parameter update module 705, capable of updating the consistency parameters through information interaction and distributed calculation among nodes, and generating a reactive power output command value based on the consistency parameters;

[0157] A power control module 706, capable of outputting reactive power according to the reactive power command value and the node adjustment capacity limit;

[0158] A result judgment module 707, capable of judging whether the voltage converges to the normal range or reaches the maximum calculation times, and deciding whether to end the adjustment process.

[0159] Further, the selection conditions of the dominant node in the node selection module 701 include at least one of the following:

[0160] The number of adjacent nodes exceeds a preset threshold;

[0161] The regulation capacity is greater than the average regulation capacity of other nodes in the cluster;

[0162] The regulation sensitivity is higher than the average sensitivity of other nodes in the cluster.

[0163] Furthermore, in the consistency parameter calculation module 704, the dynamic calculation rule of the consistency parameter λ i,t is as follows:

[0164] When the absolute value of the voltage over-limit is greater than the first threshold, the consistency parameter is calculated according to the formula λ i,1 = α × deviU i,1 ;

[0165] When the absolute value of the voltage over-limit is less than or equal to the first threshold, the consistency parameter is calculated according to the formula λ i,1 = β × signdeviU i,1 ;

[0166] Among them, λ i,t represents the consistency parameter, t represents the t-th calculation, and here it takes 1; α and β are preset consistency parameter adjustment weight coefficients; deviU i,1 is the voltage over-limit of node i; signdeviU i,t is the over-limit direction flag.

[0167] Furthermore, in non-first calculations, if the current over-limit direction is the same as the previous one and the absolute value of the voltage over-limit is less than the second threshold, the consistency parameter inherits the previous calculation result; if the over-limit directions are opposite, the consistency parameter is calculated as the product of 50% of the previous absolute value and the current direction flag.

[0168] Furthermore, in the parameter update module 705, the interactive calculation of the leading node adds a standard voltage deviation term, and its update formula is:

[0169]

[0170] Among them, ε is the deviation adjustment weight, gapU i,t is the standard voltage deviation value, and the voltage deviation value is the difference between the voltage of the leading node at this moment and the standard voltage, that is, gapU i,t = U i,t - 1.

[0171] Furthermore, the weight η i,j of the information interaction between nodes in the parameter update module 705 is dynamically allocated according to the communication relationship identifier, and the calculation formula is:

[0172]

[0173] Among them, e i,lIt is the communication relationship identifier between node i and node l. If communication can be achieved between node i and node l, then e i,l = 1. If communication cannot be achieved, then e i,l = 0. It is 1 if communication is possible, otherwise it is 0.

[0174] Furthermore, the convergence conditions in the result judgment module 707 include:

[0175] The per-unit values of the voltages of all nodes are within the non-overlimit range;

[0176] The number of adjustment times reaches the preset maximum calculation times t max .

[0177] Furthermore, in the power control module 706, the calculation rule of the reactive power output command value Q refi,t+1 is as follows:

[0178] Q refi,t+1 = λ i,t+1 ×Q imax (9)

[0179] where Q imax is the maximum reactive power adjustment capacity of node i.

[0180] An embodiment of another aspect of the present application provides a computer-readable storage medium, which stores computer-executable instructions for executing the above-mentioned Figure 1 shown distribution network cluster voltage control method based on variable weight consistency.

[0181] The device embodiments described above are only illustrative. The units described as separate components may or may not be physically separated, that is, they may be located in one place, or they may be distributed to multiple network units. Some or all of the modules can be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0182] Those of ordinary skill in the art will appreciate that all or some of the steps and systems disclosed above can be implemented as software, firmware, hardware, and appropriate combinations thereof. Some or all of the physical components can be implemented as software executed by a processor, such as a central processing unit, a digital signal processor, or a microprocessor, or as hardware, or as an integrated circuit, such as an application specific integrated circuit. Such software can be distributed on a computer-readable medium, which can include a computer storage medium (or non-transitory medium) and a communication medium (or transitory medium). As is well known to those of ordinary skill in the art, the term computer storage medium includes volatile and non-volatile, removable and non-removable media implemented in any method or technology for storing information, such as computer-readable instructions, data structures, program modules, or other data. Computer storage media includes, but is not limited to, RAM, ROM, EEPROM, flash memory or other memory technologies, CD-ROM, digital versatile disks (DVD) or other optical disk storage, magnetic cassettes, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other medium that can be used to store the desired information and that can be accessed by a computer. In addition, it is well known to those of ordinary skill in the art that communication media typically contain computer-readable instructions, data structures, program modules, or other data in a modulated data signal such as a carrier wave or other transmission mechanism, and can include any information delivery media.

[0183] The above is a specific description of the preferred embodiments of the present application, but the present application is not limited to the above embodiments. Those skilled in the art can make various equivalent deformations or substitutions without departing from the spirit of the present application, and these equivalent deformations or substitutions are all included in the scope defined by the claims of the present application.

Claims

1. A distribution network cluster voltage control method based on variable-weight consistency, characterized in that, It includes the following steps: Select an adjustment cluster, calculate the remaining adjustment capacity of each node in the adjustment cluster, and determine the adjustment capacity limit of each node according to the remaining adjustment capacity of each node; Detect the actual voltage of each node in the adjustment cluster, and determine whether there is a voltage over-limit node according to the actual voltage of each node; If there is a voltage over-limit node, calculate the voltage over-limit degree of each node; Dynamically calculate the consistency parameter of each node according to the absolute value of the voltage over-limit degree of each node and the direction flag; Through information interaction between nodes, update the consistency parameter of each node, and generate the reactive power output command value of each node based on the updated consistency parameter of each node and the adjustment capacity limit of each node; Control the voltage and power of each node based on the reactive power output command value to adjust the voltage of each node until the voltage of all nodes converges to the normal range or the number of times of calculating the voltage over-limit degree reaches the preset maximum calculation times.

2. The method according to claim 1, wherein The nodes in the adjustment cluster include a leading node, and the selection process of the leading node needs to meet at least one of the following conditions: The number of adjacent nodes of the leading node exceeds the preset threshold; The remaining adjustment capacity of the leading node is greater than the average adjustment capacity of other nodes in the adjustment cluster except the leading node; The adjustment sensitivity of the leading node is higher than the average sensitivity of other nodes in the adjustment cluster except the leading node.

3. The method according to claim 1, wherein In the step of dynamically calculating the consistency parameter of each node according to the absolute value of the voltage over-limit of each node and the direction flag quantity, the consistency parameter λ i,t The dynamic calculation rule is as follows: When the absolute value of the voltage exceeding the limit is greater than the first threshold, the consistency parameter is calculated according to the formula λ i,1 = α × deviU i,1 ; When the absolute value of the voltage exceeding the limit is less than or equal to the first threshold, the consistency parameter is calculated according to the formula λ i,1 = β × signdeviU i,1 is calculated; Among them, λ i,t represents the consistency parameter, t represents the t-th calculation; α and β are preset weight coefficients for adjusting the consistency parameter; deviU i,1 is the voltage over-limit of node i; signdeviU i,t is the over-limit direction flag.

4. The method according to claim 3, wherein In non-first calculation, if the over-limit direction of the current time is the same as that of the previous time and the absolute value of the voltage over-limit degree is less than the second threshold, the consistency parameter inherits the calculation result of the previous time; if the over-limit direction of the current time is opposite to that of the previous time, the consistency parameter is calculated according to the product of 50% of the absolute value of the voltage over-limit degree of the previous time and the direction flag of the current time.

5. The method according to claim 2, wherein The weight η of the information interaction between nodes in the step of updating the consistency parameters of each node through information interaction between nodes and generating the reactive power output command value of each node based on the updated consistency parameters of each node and the adjustment capacity limit of each node i,j is dynamically allocated according to the communication relationship identifier, and the calculation formula is: Among them, e i,l is the communication relationship identifier between node i and node l. If communication can be achieved between node i and node l, then e i,l = 1. If communication cannot be achieved, then e i,l = 0, which is 1 if communication is possible, otherwise 0.

6. The method according to claim 2, wherein In the step of updating the consistency parameter of each node through information interaction between nodes, each node in the adjustment cluster includes a leading node and a non-leading node. The standard voltage deviation term is added to the interactive calculation of the leading node, and the consistency parameter update formula of the leading node is: Among them, t is the number of times of calculating the consistency parameter after the cluster voltage exceeds the limit, ε is the deviation adjustment weight, and gapU i,t is the standard voltage deviation value, and the standard voltage deviation value is the difference between the actual voltage of the dominant node at the (t + 1)-th moment and the standard voltage, that is, gapU i,t = U i,t - 1.

7. The method according to claim 1, characterized in that, The step of adjusting the voltage of each node until the voltage of all nodes converges to the normal range or the number of times of calculating the voltage over-limit degree reaches the preset maximum calculation times includes: When the per-unit value of the voltage of all nodes is within the non-over-limit range, it indicates whether the voltage converges to the normal range; The number of times of calculating the voltage over-limit reaches the preset maximum number of calculations. Reaching the maximum number of calculations includes: when the number of adjustment times reaches the preset maximum number of calculations t max , indicating that the maximum number of calculations has been reached.

8. The method according to claim 1, wherein In the step of generating the reactive power output command value for each node based on the updated consistency parameters of each node and the regulation capacity limit of each node, the reactive power output command value Q refi,t+1 is calculated according to the following rule: Q refi,t+1 = λ i,t+1 × Q ima Among them, Q imax is the maximum reactive power regulation capacity of node i.

9. A distribution network cluster voltage control system based on variable weight consistency, characterized in that It includes: A node selection module, which can select an adjustment cluster, calculate the remaining adjustment capacity of each node in the adjustment cluster, and determine the adjustment capacity limit of each node according to the remaining adjustment capacity of each node; A node voltage over-limit judgment module, which can detect the actual voltage of each node in the adjustment cluster and determine whether there is a voltage over-limit node according to the actual voltage of each node; A voltage over-limit degree calculation module, which can calculate the voltage over-limit degree of each node when there is a voltage over-limit node; A consistency parameter calculation module, which can dynamically calculate the consistency parameter of each node according to the absolute value of the voltage over-limit degree of each node and the direction flag; A parameter update module, which can update the consistency parameters of each node through information interaction between nodes, and generate reactive power output command values for each node based on the updated consistency parameters of each node and the adjustment capacity limits of each node; A power control module, which can control the voltage and power of each node based on the reactive power output command value; A result judgment module, which can adjust the voltage of each node until the voltages of all nodes converge to the normal range or the number of times of calculating the voltage over-limit degree reaches a preset maximum calculation times.

10. The system according to claim 9, wherein The nodes in the adjustment cluster include a leading node, and the selection conditions for the leading node in the node selection module include at least one of the following: The number of adjacent nodes of the leading node exceeds a preset threshold; The remaining adjustment capacity of the leading node is greater than the average adjustment capacity of other nodes in the adjustment cluster except the leading node; The adjustment sensitivity of the leading node is higher than the average sensitivity of other nodes in the adjustment cluster except the leading node.

11. The system according to claim 9, characterized in that, In the consistency parameter calculation module, the dynamic calculation rule of the consistency parameter λ i,t is as follows: When the absolute value of the voltage exceeding the limit is greater than the first threshold, the consistency parameter is calculated according to the formula λ i,1 = α × deviU i,1 ; When the absolute value of the voltage exceeding the limit is less than or equal to the first threshold, the consistency parameter is calculated according to the formula λ i,1 = β × signdeviU i,1 ; Among them, λ i,t represents the consistency parameter, t represents the t-th calculation, and here t takes 1; α and β are preset weight coefficients for adjusting the consistency parameter; deviU i,1 is the voltage over-limit of node i; signdeviU i,t is the over-limit direction flag.

12. The system according to claim 11, wherein In non-first calculation, if the over-limit direction of the current time is the same as that of the previous time and the absolute value of the voltage over-limit degree is less than the second threshold, the consistency parameter inherits the calculation result of the previous time; if the over-limit direction of the current time is opposite to that of the previous time, the consistency parameter is calculated according to the product of 50% of the absolute value of the voltage over-limit degree of the previous time of the current time and the direction flag quantity of the current time.

13. The system according to claim 9, characterized in that The weight η of information interaction between nodes in the parameter update module i,j Is dynamically allocated according to the communication relationship identifier, and the calculation formula is: Among them, e i,l is the communication relationship identifier between node i and node l. If communication can be achieved between node i and node l, then e i,l = 1. If communication cannot be achieved, then e i,l = 0, that is, 1 if communication is possible, otherwise 0.

14. The system according to claim 10, wherein In the parameter update module, each node in the adjustment cluster includes a leading node and a non-leading node. The standard voltage deviation term is added to the interactive calculation of the leading node, and the update formula of the consistency parameter of the leading node is: Among them, t is the number of times of calculating the consistency parameter after the cluster voltage exceeds the limit, ε is the deviation adjustment weight, and gapU i,t is the standard voltage deviation value, and the standard voltage deviation value is the difference between the actual voltage of the leading node at the (t + 1)-th moment and the standard voltage, that is, gapU i,t = U i,t - 1.

15. The system according to claim 9, characterized in that, The convergence conditions in the result judgment module include: When the per-unit values of the voltages of all nodes are within the non-over-limit range, it indicates whether the voltage converges to the normal range. Reaching the maximum number of calculations, including: when the number of adjustment times reaches the preset maximum number of calculations t max , indicating that the maximum number of calculations has been reached.

16. The system according to claim 9, wherein In the power control module, the reactive power output command value Q refi,t+1 is calculated according to the following rule: Q refi,t+1 = λ i,t+1 × Q imax Among them, Q ima is the maximum reactive power regulation capacity of node i.

17. A computer-readable storage medium, characterized in that, It stores a computer program, and when the program is executed by a processor, it implements the distribution network cluster voltage control method based on variable-weight consistency as described in any one of claims 1-8.

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