Multi-target coordinated intelligent capacitor switching control method and system

Abstract

The invention relates to the field of electric power grids, in particular to a multi-target coordinated intelligent capacitor switching control method and system, and the method comprises the steps: constructing a three-dimensional state space with reactive vacancy, voltage deviation and power factor deviation as coordinate axes, and building a multi-target coordinated control model; according to the multi-target coordination control model, executing a switching action on the capacitor; the switching action execution period always meets the condition of not exceeding the vacant maximum capacity; switching parameters are adjusted according to the switching action condition during the switching action execution period; and according to the change state of the voltage and / or the power factor during the execution period of the switching action, adjusting the operation on the input channel and the input capacitor. According to the invention, multi-target coordination control of the capacitor is realized by considering voltage quality, reactive power balance and a power factor, mechanical oscillation of'switching immediately after switching and switching immediately after switching 'is eliminated, loss is reduced, annual action times of the capacitor are reduced, and power supply reliability and stability of a power distribution network are improved.

Description

Technical Field

[0001] This invention relates to the field of power grids, and in particular to a multi-objective coordinated intelligent capacitor switching control method and system. Background Technology

[0002] Reactive power compensation in low-voltage distribution networks commonly employs local compensation via parallel capacitors. Its control strategies can be broadly categorized into three types. The first type is voltage control, which simply compares the system voltage to set upper and lower limits, switching on when the voltage is below the lower limit and off when it's above the upper limit. This completely disregards reactive power demand, making it prone to overcompensation during sudden reductions in inductive loads or backfeeding from distributed power sources, threatening the safety of electrical equipment. The second type is single-target control based on reactive power or power factor, determining switching solely based on reactive power deficit or power factor deviation. While this can bring the power factor at the metering point to the acceptable range, it affects voltage, causing problems such as flickering lighting and difficulty starting motors. The third type is a "hybrid" approach, mechanically connecting voltage and power factor in series and parallel. While seemingly comprehensive in logic, the lack of clear priorities and anti-jitter mechanisms in actual operation results in capacitor banks operating over a hundred times a day, damaging contacts and shortening capacitor lifespan. Existing single-objective control suffers from drawbacks such as incomplete consideration of multiple objectives, chaotic multi-objective mixed logic, and frequent switching oscillations, resulting in shortened equipment lifespan and high line losses. There is an urgent need for a multi-objective capacitor switching control scheme that can integrate voltage, reactive power, and power factor, and can be easily parameterized on-site. Summary of the Invention

[0003] Considering the shortcomings of existing low-voltage distribution reactive power compensation methods, such as single-objective control leading to inconsistencies, chaotic multi-objective mixed logic, and frequent switching oscillations, resulting in shortened equipment lifespan and high line losses, this invention provides a multi-objective coordinated intelligent capacitor switching control method, comprising the following steps:

[0004] S100: Construct a three-dimensional state space with reactive power deficit, voltage deviation, and power factor deviation as coordinate axes, and establish a multi-objective coordinated control model;

[0005] S200: According to the multi-objective coordinated control model, a switching action is performed on the capacitor; wherein, during the execution of the switching action, the condition of not exceeding the maximum capacity of the deficit is always met;

[0006] S300: During the execution of the throwing and cutting action, adjust the throwing and cutting parameters according to the throwing and cutting action situation;

[0007] S400: Adjust the operation of the input channel and the input capacitor based on the changes in voltage and / or power factor during the execution of the switching operation.

[0008] Preferably, in S100, a three-dimensional state space is constructed with reactive power deficit, voltage deviation, and power factor deviation as coordinate axes, and a multi-objective coordinated control model is established, specifically as follows:

[0009] Based on the topological characteristics of the power grid distribution area, the initial weights of the target parameters are set; wherein, the target parameters include voltage qualification rate, reactive power balance, and power factor compliance rate.

[0010] Several hard constraint boundaries are defined; wherein, the several hard constraint boundaries include voltage safety constraints, reactive power capacity constraints, and equipment operation constraints;

[0011] Establish a voltage-reactive power sensitivity matrix to quantify the marginal contribution of a single capacitor bank to the capacitor and its compensation efficiency for reactive power deficit.

[0012] The multi-objective decision results of reactive power, voltage, and power factor are mapped to several control mode channels, and the switching priority flag bits of the several control mode channels are set.

[0013] Based on the initial weights of the target parameters, the hard constraint boundaries, the voltage-reactive power sensitivity matrix, and the control mode channels, a three-dimensional state space is constructed with reactive power deficit, voltage deviation, and power factor deviation as coordinate axes, and a multi-objective coordinated control model is established.

[0014] Preferably, in S200, according to the multi-objective coordinated control model, the capacitor switching action is performed, specifically as follows:

[0015] Before performing the switching operation on the capacitor, the capacity deficit is determined based on the candidate capacity to be cut or added; based on the capacity deficit, it is determined whether the switching conditions are met.

[0016] If the switching conditions are met, then the capacitor is switched on or off according to the multi-objective coordinated control model.

[0017] If the switching conditions are not met, the switching action will not be performed on the capacitor.

[0018] Preferably, in S300, during the execution of the throwing and cutting action, the throwing and cutting parameters are adjusted according to the throwing and cutting action situation, specifically as follows:

[0019] During the execution of the throwing action, the number of throwing actions has been obtained, and it is determined whether the number of throwing actions exceeds a preset threshold.

[0020] If the preset number of times threshold is exceeded, the voltage hysteresis and power factor hysteresis will be amplified; if the preset number of times threshold is not exceeded, the voltage hysteresis and power factor hysteresis will not be changed.

[0021] Preferably, in S400, the operation on the input channel and the input capacitor is adjusted according to the changes in voltage and / or power factor during the execution of the switching operation, specifically as follows:

[0022] Acquire data on the changes in charge and / or power factor during the switching action, and determine whether the charge and / or power factor exceed a preset threshold and show an increasing trend based on the data.

[0023] If so, the input channel is locked first; if the increasing trend does not reverse in the next cycle, the input and output capacitors are actively and gradually disconnected.

[0024] If not, then the current throwing and cutting action will remain unchanged.

[0025] On the other hand, the present invention provides a multi-objective coordinated intelligent capacitor switching control system, the system comprising the following modules:

[0026] The model building module is used to construct a three-dimensional state space with reactive power deficit, voltage deviation, and power factor deviation as coordinate axes, and to establish a multi-objective coordinated control model.

[0027] The switching action execution module is used to perform switching actions on the capacitor according to the multi-objective coordinated control model; wherein, during the execution of the switching action, the condition of not exceeding the maximum capacity of the deficit is always met;

[0028] The throwing and cutting parameter adjustment module is used to adjust the throwing and cutting parameters according to the throwing and cutting action during the execution of the throwing and cutting action;

[0029] The graded blocking operation module is used to adjust the operation of the input channel and the input capacitor according to the changes in voltage and / or power factor during the execution of the switching action.

[0030] Preferably, the model building module is used to construct a three-dimensional state space with reactive power deficit, voltage deviation, and power factor deviation as coordinate axes, and to establish a multi-objective coordinated control model, specifically:

[0031] Based on the topological characteristics of the power grid distribution area, the initial weights of the target parameters are set; wherein, the target parameters include voltage qualification rate, reactive power balance, and power factor compliance rate.

[0032] Several hard constraint boundaries are defined; wherein, the several hard constraint boundaries include voltage safety constraints, reactive power capacity constraints, and equipment operation constraints;

[0033] Establish a voltage-reactive power sensitivity matrix to quantify the marginal contribution of a single capacitor bank to the capacitor and its compensation efficiency for reactive power deficit.

[0034] The multi-objective decision results of reactive power, voltage, and power factor are mapped to several control mode channels, and the switching priority flag bits of the several control mode channels are set.

[0035] Based on the initial weights of the target parameters, the hard constraint boundaries, the voltage-reactive power sensitivity matrix, and the control mode channels, a three-dimensional state space is constructed with reactive power deficit, voltage deviation, and power factor deviation as coordinate axes, and a multi-objective coordinated control model is established.

[0036] Preferably, the switching action execution module is used to perform switching actions on the capacitor according to the multi-objective coordinated control model, specifically as follows:

[0037] Before performing the switching operation on the capacitor, the capacity deficit is determined based on the candidate capacity to be cut or added; based on the capacity deficit, it is determined whether the switching conditions are met.

[0038] If the switching conditions are met, then the capacitor is switched on or off according to the multi-objective coordinated control model.

[0039] If the switching conditions are not met, the switching action will not be performed on the capacitor.

[0040] Preferably, the throwing and cutting parameter adjustment module is used to adjust the throwing and cutting parameters according to the throwing and cutting action during the execution of the throwing and cutting action, specifically as follows:

[0041] During the execution of the throwing action, the number of throwing actions has been obtained, and it is determined whether the number of throwing actions exceeds a preset threshold.

[0042] If the preset number of times threshold is exceeded, the voltage hysteresis and power factor hysteresis will be amplified; if the preset number of times threshold is not exceeded, the voltage hysteresis and power factor hysteresis will not be changed.

[0043] Preferably, the graded interlocking operation module is used to adjust the operation on the input channel and the input capacitor according to the changes in voltage and / or power factor during the execution of the switching action, specifically:

[0044] Acquire data on the changes in charge and / or power factor during the switching action, and determine whether the charge and / or power factor exceed a preset threshold and show an increasing trend based on the data.

[0045] If so, the input channel is locked first; if the increasing trend does not reverse in the next cycle, the input and output capacitors are actively and gradually disconnected.

[0046] If not, then the current throwing and cutting action will remain unchanged.

[0047] Compared with the prior art, the present invention has the following beneficial effects:

[0048] The multi-objective coordinated intelligent capacitor switching control method and system of this invention constructs a three-dimensional state space with reactive power deficit, voltage deviation, and power factor deviation as coordinate axes to establish a multi-objective coordinated control model. Based on the multi-objective coordinated control model, capacitor switching actions are performed. During the switching action, the condition of not exceeding the maximum capacity of the deficit is always met. Switching parameters are adjusted according to the switching action situation. The operation on the connected channels and already switched capacitors is adjusted according to the changes in voltage and / or power factor during the switching action. By taking into account voltage quality, reactive power balance, and power factor, multi-objective coordinated control of capacitors is achieved, eliminating the mechanical oscillation of "switching immediately after switching, and switching back on immediately after switching," reducing losses, decreasing the annual number of capacitor operations, and improving the reliability and stability of the power distribution network.

[0049] The multi-objective coordinated intelligent capacitor switching control method and system of the present invention have the following beneficial effects:

[0050] First, switching oscillations are significantly reduced. Through three-dimensional state space modeling and expectation verification strategies, the number of daily switching operations of capacitors is reduced from 60-80 times to 20-30 times, eliminating the mechanical oscillations of "switching immediately after switching and reversing immediately after switching".

[0051] Secondly, the operating accuracy has been greatly improved, with the power factor fluctuation range reduced from ±0.08 to ±0.03, and the steady-state value locked in the range of 0.95-0.98, taking into account both voltage quality and reactive power balance;

[0052] Third, reliability is improved, line loss is reduced by 5%, capacitor switch contact life is doubled, equipment maintenance-free period is extended, and operation and maintenance costs are significantly reduced.

[0053] Fourth, it is highly adaptable, supports simple on-site parameterization settings, can adapt to the load characteristics of different distribution network areas, and is compatible with distributed power source access scenarios. Attached Figure Description

[0054] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments 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 drawings can be obtained based on these drawings without creative effort. Wherein:

[0055] Figure 1 This is a flowchart of a multi-objective coordinated intelligent capacitor switching control method provided by the present invention.

[0056] Figure 2 It is the circuit system corresponding to the intelligent capacitor switching control method.

[0057] Figure 3 This is the voltage regulation process of the intelligent capacitor switching control method.

[0058] Figure 4 It is the reactive power regulation process of the intelligent capacitor switching control method.

[0059] Figure 5 It is the power factor adjustment process of the intelligent capacitor switching control method.

[0060] Figure 6 This is a structural diagram of a multi-objective coordinated intelligent capacitor switching control system provided by the present invention. Detailed Implementation

[0061] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, the specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are only for explaining the present invention and not for limiting the present invention. Furthermore, it should be noted that, for ease of description, only the parts related to the present invention are shown in the accompanying drawings, not all structures. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without inventive effort are within the scope of protection of the present invention.

[0062] The terms "comprising" and "having," and any variations thereof, used in this invention are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or apparatus that includes a series of steps or units is not limited to the steps or units listed, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to such process, method, product, or apparatus.

[0063] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of the invention. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0064] Please see Figure 1 As shown, this invention provides a multi-objective coordinated intelligent capacitor switching control method, which includes the following steps:

[0065] S100: Construct a three-dimensional state space with reactive power deficit, voltage deviation, and power factor deviation as coordinate axes, and establish a multi-objective coordinated control model.

[0066] Furthermore, in S100, a three-dimensional state space is constructed with reactive power deficit, voltage deviation, and power factor deviation as coordinate axes, and a multi-objective coordinated control model is established, specifically as follows:

[0067] Based on the topological characteristics of the power grid distribution area, the initial weights of the target parameters are set; among them, the target parameters include voltage qualification rate, reactive power balance, and power factor compliance rate.

[0068] Several hard constraint boundaries are defined; among them, the hard constraint boundaries include voltage safety constraints, reactive power capacity constraints, and equipment operation constraints.

[0069] Establish a voltage-reactive power sensitivity matrix to quantify the marginal contribution of a single capacitor bank to the capacitor and its compensation efficiency for reactive power deficit.

[0070] The multi-objective decision results of reactive power, voltage, and power factor are mapped to several control mode channels, and the switching priority flag bits of several control mode channels are set.

[0071] Based on the initial weights of the target parameters, several hard constraint boundaries, voltage-reactive power sensitivity matrix, and several control mode channels, a three-dimensional state space with reactive power deficit, voltage deviation, and power factor deviation as coordinate axes is constructed, and a multi-objective coordinated control model is established. Among them, reactive power deficit can be calculated by real-time collected grid parameters, voltage deviation is the difference between the actual grid voltage and the rated voltage, and power factor deviation is the difference between the actual power factor and the target power factor.

[0072] Please see Figure 2 The circuit system corresponding to the intelligent capacitor switching control method mainly includes a data acquisition unit, an MCU, a drive execution unit, a communication interface, and a human-machine interaction unit. The data acquisition unit is connected to the power grid side and includes temperature, current, and voltage sensors to collect the operating temperature of the equipment on the power grid side, the power grid current, and the power grid voltage, respectively. The data acquisition unit communicates with the MCU through an ADC channel.

[0073] The MCU can be, but is not limited to, an STM32G070RB microcontroller, equipped with an ARM Cortex-MO+ 32-bit RISC processor, a maximum operating frequency of 64MHz, 128Kb Flash memory and 16kB SRAM, and supports 2 I2C interfaces, 3 USART interfaces, and 2 SPI interfaces, responsible for data processing, logic judgment, and control command output. The drive execution unit can be, but is not limited to, a BL8023 zero-crossing detection / magnetic latching relay driver chip, receiving digital output commands from the MCU to achieve precise relay switching control. The human-machine interface unit can connect to a DC868C2E LCD display via an I2C interface and connect to 3 buttons and DIP switches via GPIO interfaces for on-site parameter setting and equipment operating status display; it can also display parameters such as current power factor, voltage, and switching count on the LCD display. The communication interface uses an Ethernet MAC interface and an RJ45 interface to achieve serial and network communication, responding to master station commands; the communication interface feeds back the equipment operating status and switching records to the master station and receives remote control commands from the master station. In addition, the above circuit system also includes a reset circuit, an 8MHz external crystal oscillator, and a JW501878L33 power driver module (not shown in the figure), with a power supply voltage range of 1.8V-3.6V to ensure stable operation of the MCU.

[0074] The multi-objective coordinated control model is a hierarchical decision-making system based on the three-dimensional coupling relationship of "voltage-reactive power-power factor". Its construction process follows a progressive path of "objective hierarchicalization-constraint delimitation-strategy arbitration-execution optimization". According to the requirements of the distribution network area, scenario adaptation is achieved through modular combination and priority configuration. The construction process of the multi-objective coordinated control model is divided into the following five stages:

[0075] Target weight initialization phase: Based on the topological characteristics and power supply quality of the distribution network area, initial weights are set for the three core targets: voltage qualification rate, reactive power balance, and power factor compliance rate. For example, when low voltage problems are prominent at the end of the line, the voltage target weight is adjusted to above 0.5; when industrial users are subject to strict assessments, the power factor target weight is adjusted to above 0.6; the total weights are normalized to 1, forming a dynamically adjustable target function vector.

[0076] Constraint modeling stage: Determine three types of hard constraint boundaries—voltage constraints (e.g., 198V-235V), reactive capacity constraints (e.g., single capacitor capacity and total compensation limit), and equipment action constraints (e.g., daily action limit and action interval time). The above constraints constitute an insurmountable "action forbidden zone," and any switching command must first pass through all the above constraint verification layers for screening.

[0077] Decoupling stage: Establish voltage-reactive power sensitivity matrix to quantify the marginal contribution of a single capacitor bank to node voltage and its compensation efficiency for reactive power deficit; obtain sensitivity coefficients under different load conditions through Jacobian matrix approximation or historical data regression to provide quantitative basis for strategy arbitration.

[0078] In the anti-shake and lockout rule embedding stage: an "expected verification" mechanism is designed to simulate the state changes after switching before the command is issued; if the simulation results show that the target swing will exceed the hysteresis band (e.g., voltage hysteresis of 5V, power factor hysteresis of 0.05), or reach the lockout threshold (e.g., voltage exceeding the limit, harmonic exceeding the standard), the command is directly intercepted and marked as "anti-shake lockout".

[0079] Mode mapping and channel switching stage: The abstract multi-objective decision results are mapped to specific control mode channels; in the hybrid mode, the "power factor priority" or "voltage priority" logic branch is automatically selected by switching priority flag bits; in the single-objective mode, interference from other dimensions is shielded to simplify the decision path.

[0080] By establishing a multi-objective coordinated control model through the above process, multi-dimensional capacitor switching control can be performed on three objectives: voltage, reactive power, and power factor, thereby improving the reliability and accuracy of switching control.

[0081] The multi-objective coordinated control model does not exist in isolation, but rather forms a "framework-instance" subordinate relationship with the above five stages through pattern parameterization:

[0082] The voltage regulation mode is a simplified single-objective instance of the model. In this mode, the policy arbitration mechanism blocks reactive power and power factor inputs and only retains the voltage over-limit judgment. The objective weight vector degenerates into [voltage weight = 1, reactive power weight = 0, power factor weight = 0]. During the debouncing and blocking rule embedding stage, only voltage hysteresis is monitored, and other dimensions of debouncing logic are dormant. The above mode is suitable for pure voltage governance scenarios and has the lowest computational overhead.

[0083] The reactive power regulation mode is an example of open-loop compensation. The strategy arbitration mechanism uses the absolute value of reactive power deficit as the sole criterion, without considering the refined requirements of power factor assessment. The constraint condition of the capacitor optimization engine is simplified to "minimum single-step compensation error". It no longer evaluates whether the power factor after compensation falls exactly within the assessment range. The above mode is suitable for occasions with many harmonic sources, quickly balancing reactive power but not finely optimizing the power factor.

[0084] The power factor adjustment mode is an example of closed-loop optimization. Unlike the reactive power adjustment mode, the above mode calculates the precise reactive power deficit by converting the "average of the upper and lower limits of the target power factor," requiring that the compensated power factor must fall within the range. The strategy arbitration mechanism introduces an "range satisfaction" assessment. Even if the reactive power is not absolutely balanced, the action stops as long as the power factor meets the target, reflecting the "performance-oriented" characteristic.

[0085] The hybrid mode, primarily based on power factor, is a dual-objective weighted instance and a core application form. In this mode, the strategy arbitration mechanism employs a "master-slave logic": power factor output serves as the primary criterion, and voltage output as the secondary criterion. Specifically, the strategy arbitration mechanism first performs demand calculations along the power factor dimension, generating a set of candidate actions. Then, it performs voltage safety checks on this set of candidate actions. If a candidate action leads to voltage exceeding limits, "demand pruning" is initiated, probing from smallest to largest capacity until the largest capacitor causing the voltage problem is not found. During the debouncing and latching rule embedding phase, power factor hysteresis and voltage hysteresis are monitored simultaneously. If either dimension falls within the hysteresis band, instruction interception is triggered. This mode fully reuses all modules of the model, achieving logic optimization only through priority flag configuration.

[0086] The voltage-centric hybrid mode is a dual-objective inverse weighted example, logically mirroring the power factor-first mode: the strategy arbitration mechanism first satisfies the voltage regulation requirement, generating a set of candidate actions; then it verifies whether the candidate actions will cause the power factor to seriously exceed the limit (e.g., below 0.85 or above 0.95). If a risk exists, the "capacity reduction" strategy is activated, selecting the second largest capacitor or initiating a collaborative compensation request from adjacent transformer areas. The anti-jitter and blocking rules emphasize voltage hysteresis, relaxing power factor requirements when the voltage approaches the limit, reflecting the practical principle of "ensuring voltage while considering power factor".

[0087] S200: Based on the multi-objective coordinated control model, the capacitor switching action is performed; wherein, during the execution of the switching action, the condition of not exceeding the maximum capacity of the deficit is always met.

[0088] Furthermore, in S200, based on the multi-objective coordinated control model, the capacitor switching action is performed, specifically as follows:

[0089] Before performing the switching operation on the capacitor, the capacity shortage is determined based on the candidate capacitors to be cut or added; based on the capacity shortage, it is determined whether the switching conditions are met.

[0090] If the switching conditions are met, the capacitor switching action is performed according to the multi-objective coordinated control model;

[0091] If the switching conditions are not met, the switching action will not be performed on the capacitor.

[0092] The switching action performed on the capacitor is mainly achieved through the following process:

[0093] Voltage monitoring and prediction: Real-time collection of voltage at distribution transformer outlets and key nodes of the line, combined with load prediction algorithms to predict the voltage trend in the next 3-5 minutes. Its role is to provide advance prediction for switching decisions, avoid excessively high voltage after compensation leading to excessively high no-load at night. In the voltage-based hybrid mode, the output directly determines the start threshold of strategy arbitration.

[0094] Dynamic calculation of reactive power deficit: Based on real-time active power and target power factor upper and lower limits, the "reactive power deficit" and "over-compensation margin" are dynamically calculated. The compensation demand value is refreshed every second, and the results are output to the capacitor optimization algorithm. Its function is to ensure that the reactive power compensation error gradually converges after each group of capacitors is put into operation, avoiding the oscillation problem of the traditional nine-zone diagram.

[0095] Power factor assessment: Calculate the instantaneous power factor and record the weighted average value within a 15-minute sliding window to meet the power bureau's assessment requirements; when in a hybrid mode with power factor as the main factor, the assessment result takes precedence over the assessment result corresponding to the voltage, but its output will include a voltage influence coefficient to prevent overcompensation from causing voltage over-limit.

[0096] Optimized capacitor capacity: After receiving reactive power deficit or voltage compensation requirements, integer planning is performed under the principle of "not exceeding the maximum capacity of the deficit". Its function is reflected in: prioritizing the switching of large capacity capacitors can quickly approach the target value and reduce the number of switching operations; when disconnecting, large capacity capacitors are also disconnected first to avoid repeated adjustments caused by "cutting small and leaving large". The above process is the core link of the switching operation.

[0097] Strategy arbitration and priority determination: When the control needs of voltage, reactive power, and power factor conflict (for example, the voltage is too low and needs to be activated, but the power factor has exceeded the upper limit), arbitration is carried out according to the preset priority flag (for example, the flag is "0", indicating that the power factor takes priority; the flag is "1", indicating that the voltage takes priority) or the mixed weight formula (for example, the comprehensive score = 0.6 * power factor score + 0.4 * voltage score), and a unique action command is output.

[0098] Action timing and delay control: Manage the "action delay" parameter to ensure that the system state is stable after capacitor switching before entering the next round of calculation. Its function is to filter out transient disturbances and prevent misjudgments caused by sudden load changes. New instructions are blocked during the delay period, but emergency blocking conditions are continuously monitored.

[0099] Triggering interlocking and protection mechanisms: Fault detection independent of control logic, continuously monitoring abnormal signals such as harmonic distortion rate, capacitor temperature, and switch failure; once the limit is exceeded, a forced interlocking signal is immediately sent to the strategy arbitration mechanism, which unconditionally terminates the current process and executes a "full cut" or "hold" command to ensure safety.

[0100] Before performing the switching operation on the capacitor, a pre-emptive check is performed to ensure that the candidate capacity is traversed in descending order starting from the maximum available capacity, thus ensuring the accuracy of the switching operation.

[0101] Please see Figures 3 to 5 These correspond to voltage regulation, reactive power regulation, and power factor regulation processes, respectively. During the switching operations, different modes of switching operations are implemented based on the actual ambient voltage, actual ambient reactive power, and actual ambient power factor to ensure the safety and stability of the power grid operation to the greatest extent.

[0102] S300: Adjusts the throwing and cutting parameters according to the throwing and cutting action during the execution of the throwing and cutting action.

[0103] Furthermore, in S300, during the execution of the switching action, the switching parameters are adjusted according to the switching action situation, specifically as follows:

[0104] During the execution of the throwing action, the number of throwing actions is obtained, and it is determined whether the number of throwing actions exceeds a preset threshold.

[0105] If the preset number of times threshold is exceeded, the voltage hysteresis and power factor hysteresis will be amplified; if the preset number of times threshold is not exceeded, the voltage hysteresis and power factor hysteresis will not be changed.

[0106] In actual operation, the number of switching actions is recorded. If the number of switching actions exceeds 30, the voltage hysteresis and power factor hysteresis are automatically amplified to 1.5 times their initial values. If the number of switching actions does not exceed 30, the voltage hysteresis and power factor hysteresis remain unchanged. This method achieves forced reduction of sensitivity and reduces mechanical wear.

[0107] S400: Adjusts the operation of the input channel and the input capacitor based on the changes in voltage and / or power factor during the switching operation.

[0108] Furthermore, in S400, the operation on the switched-in channel and the switched-in capacitor is adjusted according to the changes in voltage and / or power factor during the switching operation, specifically as follows:

[0109] Acquire data on changes in charge and / or power factor during the switching action, and determine whether the charge and / or power factor exceed a preset threshold and show an increasing trend based on the data.

[0110] If so, the input channel will be locked first; if the increasing trend does not reverse in the next cycle, the already input and output capacitors will be actively and gradually disconnected.

[0111] If not, then the current throwing and cutting action will remain unchanged.

[0112] In actual operation, when it is determined that the charge exceeds the preset voltage threshold (e.g., 1.15UN) and / or the power factor exceeds the preset power factor threshold (e.g., 0.98) and the charge and / or power factor show an increasing trend, the input channel is first locked; if the increasing trend does not reverse in the next cycle, the input capacitors are actively and gradually disconnected, thereby avoiding the instantaneous undercompensation caused by "all disconnected once locked".

[0113] The multi-objective coordinated intelligent capacitor switching control method of this invention was applied to a low-voltage distribution network area. The original reactive power compensation device in this area was switched on and off approximately 70 times per day, with a power factor fluctuation range of ±0.07 and a line loss rate of 8%. After adopting the method of this invention, the daily capacitor switching frequency was reduced to 25 times, the power factor stabilized at 0.96-0.98 with a fluctuation range of ±0.02, the line loss rate decreased to 7.6%, the wear of capacitor switch contacts was significantly reduced, and the operational stability of the equipment was greatly improved.

[0114] Please see Figure 6 As shown, the present invention provides a multi-objective coordinated intelligent capacitor switching control system, which includes the following modules:

[0115] The model building module is used to construct a three-dimensional state space with reactive power deficit, voltage deviation, and power factor deviation as coordinate axes, and to establish a multi-objective coordinated control model.

[0116] The switching action execution module is used to perform switching actions on the capacitor according to the multi-objective coordinated control model; wherein, during the execution of the switching action, the condition of not exceeding the maximum capacity of the deficit is always met;

[0117] The throwing and cutting parameter adjustment module is used to adjust the throwing and cutting parameters according to the throwing and cutting action during the execution of the throwing and cutting action;

[0118] The graded interlocking operation module is used to adjust the operation of the input channel and the input capacitor based on the changes in voltage and / or power factor during the execution of the switching action.

[0119] Furthermore, the model building module is used to construct a three-dimensional state space with reactive power deficit, voltage deviation, and power factor deviation as coordinate axes, and to establish a multi-objective coordinated control model, specifically:

[0120] Based on the topological characteristics of the power grid distribution area, the initial weights of the target parameters are set; among them, the target parameters include voltage qualification rate, reactive power balance, and power factor compliance rate.

[0121] Several hard constraint boundaries are defined; among them, the hard constraint boundaries include voltage safety constraints, reactive power capacity constraints, and equipment operation constraints.

[0122] Establish a voltage-reactive power sensitivity matrix to quantify the marginal contribution of a single capacitor bank to the capacitor and its compensation efficiency for reactive power deficit.

[0123] The multi-objective decision results of reactive power, voltage, and power factor are mapped to several control mode channels, and the switching priority flag bits of several control mode channels are set.

[0124] Based on the initial weights of the target parameters, several hard constraint boundaries, voltage-reactive power sensitivity matrix, and several control mode channels, a three-dimensional state space with reactive power deficit, voltage deviation, and power factor deviation as coordinate axes is constructed, and a multi-objective coordinated control model is established.

[0125] Furthermore, the switching action execution module is used to perform switching actions on the capacitor according to the multi-objective coordinated control model, specifically as follows:

[0126] Before performing the switching operation on the capacitor, the capacity shortage is determined based on the candidate capacitors to be cut or added; based on the capacity shortage, it is determined whether the switching conditions are met.

[0127] If the switching conditions are met, the capacitor switching action is performed according to the multi-objective coordinated control model;

[0128] If the switching conditions are not met, the switching action will not be performed on the capacitor.

[0129] Furthermore, the switching parameter adjustment module is used to adjust the switching parameters according to the switching action during the execution of the switching action, specifically as follows:

[0130] During the execution of the throwing action, the number of throwing actions is obtained, and it is determined whether the number of throwing actions exceeds a preset threshold.

[0131] If the preset number of times threshold is exceeded, the voltage hysteresis and power factor hysteresis will be amplified; if the preset number of times threshold is not exceeded, the voltage hysteresis and power factor hysteresis will not be changed.

[0132] Furthermore, the graded interlocking operation module is used to adjust the operation on the input channel and the input capacitor based on the changes in voltage and / or power factor during the switching operation, specifically:

[0133] Acquire data on changes in charge and / or power factor during the switching action, and determine whether the charge and / or power factor exceed a preset threshold and show an increasing trend based on the data.

[0134] If so, the input channel will be locked first; if the increasing trend does not reverse in the next cycle, the already input and output capacitors will be actively and gradually disconnected.

[0135] If not, then the current throwing and cutting action will remain unchanged.

[0136] The operation and effect of the multi-objective coordinated intelligent capacitor switching control system of the present invention are consistent with the above-described multi-objective coordinated intelligent capacitor switching control method, and the multi-objective coordinated intelligent capacitor switching control system will not be described again here.

[0137] Through the above description of the embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of a necessary general-purpose hardware platform, or by a combination of hardware and software. Based on this understanding, the above technical solutions, in essence or the part that contributes to the prior art, can be embodied in the form of a computer product. The present invention can take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0138] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Other embodiments may also be used. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A multi-objective coordinated intelligent capacitor switching control method, characterized in that, The method comprises the following steps: S100: constructing a three-dimensional state space with reactive power shortage, voltage deviation, and power factor deviation as coordinate axes, and establishing a multi-objective coordinated control model; S200: performing switching actions on the capacitors according to the multi-objective coordinated control model; wherein the switching actions are always performed under the condition that the maximum capacity of the shortage is not exceeded during the execution of the switching actions; S300: adjusting the switching parameters during the execution of the switching actions according to the switching action conditions; S400: adjusting the operation of the input channels and the already switched capacitors according to the change state of the voltage and / or power factor during the execution of the switching actions.

2. The method of claim 1, wherein, in S100, a three-dimensional state space with reactive power shortage, voltage deviation, and power factor deviation as coordinate axes is constructed, and a multi-objective coordinated control model is established, specifically: According to the topological characteristics of the power distribution network of the power grid, the initial weights of the target parameters are set; wherein the target parameters include voltage qualification rate, reactive power balance degree, and power factor compliance rate; A plurality of hard constraint boundaries are determined; wherein the plurality of hard constraint boundaries include voltage safety constraints, reactive power capacity constraints, and device action constraints; A voltage-reactive power sensitivity matrix is established to quantify the marginal contribution of a single group of capacitor inputs to the capacitors and the compensation efficiency of the reactive power shortage; The multi-objective decision results for reactive power, voltage, and power factor are mapped to a plurality of control mode channels, and the switching priority flag bits of the plurality of control mode channels are set; According to the initial weights of the target parameters, the plurality of hard constraint boundaries, the voltage-reactive power sensitivity matrix, and the plurality of control mode channels, a three-dimensional state space with reactive power shortage, voltage deviation, and power factor deviation as coordinate axes is constructed, and a multi-objective coordinated control model is established.

3. The method of claim 1, wherein, in S200, switching actions are performed on the capacitors according to the multi-objective coordinated control model, specifically: Before performing switching actions on the capacitors, the capacity shortage is determined according to the candidate capacity to be switched off or input; and whether the switching condition is met is determined according to the capacity shortage; If the switching condition is met, switching actions are performed on the capacitors according to the multi-objective coordinated control model; If the switching condition is not met, no switching actions are performed on the capacitors.

4. The method of claim 1, wherein, in S300, the switching parameters are adjusted during the execution of the switching actions according to the switching action conditions, specifically: During the execution of the switching actions, the number of switching actions performed is obtained, and whether the number of switching actions performed exceeds a preset number threshold is determined; If the preset number threshold is exceeded, the voltage return deviation and the power factor return deviation are enlarged; if the preset number threshold is not exceeded, the voltage return deviation and the power factor return deviation are not changed.

5. The method of claim 1, wherein, in S400, the operation of the input channels and the already switched capacitors is adjusted according to the change state of the voltage and / or power factor during the execution of the switching actions, specifically: ​ ​ ​ ​ acquiring variation data of the charge and / or power factor during the switching action execution, and determining whether the charge and / or power factor exceeds a preset threshold and presents an increasing trend according to the variation data; if yes, locking the input channel first; if the increasing trend does not reverse in the next period, actively cutting off the switched capacitor step by step; if no, keeping the current switching action execution state unchanged.

6. A multi-objective coordinated intelligent capacitor switching control system, characterized in that, The system comprises the following modules: a model establishing module, configured to construct a three-dimensional state space with reactive power shortage, voltage deviation and power factor deviation as coordinate axes, and establish a multi-objective coordinated control model; a switching action execution module, configured to execute switching action on the capacitor according to the multi-objective coordinated control model; wherein the switching action execution always satisfies the condition of not exceeding the maximum capacity of the shortage; a switching parameter adjusting module, configured to adjust the switching parameter according to the switching action during the switching action execution; a hierarchical locking operation module, configured to adjust the operation on the input channel and the switched capacitor according to the variation state of the voltage and / or power factor during the switching action execution.

7. The system according to claim 6, wherein the model establishing module is configured to construct a three-dimensional state space with reactive power shortage, voltage deviation and power factor deviation as coordinate axes, and establish a multi-objective coordinated control model, specifically: setting initial weights of target parameters according to the topological characteristics of the power distribution network in the power grid; wherein the target parameters include voltage qualification rate, reactive power balance degree and power factor compliance rate; determining a plurality of hard constraint boundaries; wherein the plurality of hard constraint boundaries include voltage safety constraint, reactive power capacity constraint and device action constraint; establishing a voltage-reactive power sensitivity matrix to quantify the marginal contribution of a single capacitor input to the capacitor and the compensation efficiency of the reactive power shortage; mapping the multi-objective decision results on the reactive power, voltage and power factor into a plurality of control mode channels, and setting switching priority flag bits of the plurality of control mode channels; constructing a three-dimensional state space with reactive power shortage, voltage deviation and power factor deviation as coordinate axes, and establishing a multi-objective coordinated control model according to the initial weights of the target parameters, the plurality of hard constraint boundaries, the voltage-reactive power sensitivity matrix and the plurality of control mode channels.

8. The system according to claim 6, wherein the switching action execution module is configured to execute switching action on the capacitor according to the multi-objective coordinated control model, specifically: determining a capacity shortage according to the cut-off or input candidate capacity before executing switching action on the capacitor, and determining whether the switching condition is met according to the capacity shortage; if the switching condition is met, executing switching action on the capacitor according to the multi-objective coordinated control model; if the switching condition is not met, not executing switching action on the capacitor.

9. The system according to claim 6, wherein the switching parameter adjusting module is configured to adjust the switching parameter according to the switching action during the switching action execution, specifically: acquiring the number of switched actions during the switching action execution, and determining whether the number of switched actions exceeds a preset number threshold. If the preset number threshold is exceeded, the voltage and power factor hysteresis are amplified; if the preset number threshold is not exceeded, the voltage and power factor hysteresis are not changed.

10. The system of claim 6, wherein, The hierarchical blocking operation module is configured to adjust the operation of the input channel and the switched-in capacitor according to the change state of the voltage and / or power factor during the switching action execution, in particular: obtain change data of the voltage and / or power factor during the switching action execution, and determine whether the voltage and / or power factor exceeds a preset threshold and presents an increasing trend according to the change data; if yes, first block the input channel; if the increasing trend has not been reversed in the next cycle, actively cut off the switched-in capacitor step by step; if no, keep the current switching action execution state unchanged.

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