An online configuration and dynamic regulation method for low-voltage reactive power compensation system of water conservancy pumping station

Abstract

The application discloses a kind of water conservancy pump station low-voltage reactive power compensation system online configuration and dynamic regulation method, it is related to electrical automation control technical field, to solve the technical problem that traditional method cannot actively respond to water hammer impact and leads to system impedance mutation and resonance risk, and lack of water pump and compensation device collaborative control ability, comprising the following steps: S1: online construction and update pump station hydraulic-electric coupling dynamic model;S2: based on hydraulic-electric coupling dynamic model, for the water pump start-stop of water hammer and electrical disturbance induced in pump station operation and valve regulation operation, predict the system equivalent impedance change path that it will cause, and combine preset impedance safety boundary, plan a safe impedance track.The application constructs model, and based on this model, a smooth and avoid resonance risk area safe impedance track is planned for pump station key operation in advance, realizes the fundamental change from passive response to active defense.

Description

Technical Field

[0001] This invention relates to the field of electrical automation control technology, and more specifically, to a method for online configuration and dynamic control of a low-voltage reactive power compensation system for a water conservancy pumping station. Background Technology

[0002] In the operation of water conservancy pumping stations, low-voltage reactive power compensation systems are crucial for maintaining grid stability and improving energy efficiency. Traditional configuration methods are mostly based on fixed capacity calculations and group switching under steady-state conditions, and their control logic is usually based on feedback control of real-time power factor or voltage level.

[0003] However, a long-overlooked but extremely dangerous special operating condition exists in pumping station operations: hydraulic hammer (i.e., the "water hammer" phenomenon) caused by the start-up and shutdown of pumps and rapid valve movements. This transient hydraulic disturbance is coupled to the electrical side through the pump's variable frequency drive (VFD) system, causing not only a momentary surge of impulsive reactive power and harmonic current, but more seriously, a drastic change in the system's equivalent impedance characteristics at the pumping station's connection point. At this time, if traditional reactive power compensation devices (such as capacitor banks, static var generators (SVG), and active power filters (APF) still respond independently according to their predetermined logic, their output impedance characteristics may form an unfavorable matching relationship with the abruptly changed system impedance at a specific frequency, easily inducing local or global electrical resonance. This resonance can lead to overload damage to the compensation devices and malfunctioning protection systems, or even severe oscillations in the bus voltage, threatening the safe and stable operation of the entire pumping station's electrical system.

[0004] Existing technologies lack methods for modeling and actively intervening in the dynamic coupling process across the hydraulic and electrophysical domains of "water hammer-frequency conversion-compensation." Their control is fragmented and a posteriori, failing to pre-plan and actively shape the evolution path of system impedance during critical transient processes, thus failing to fundamentally avoid resonance risks. Therefore, how to achieve a dynamic control method capable of online sensing of hydraulic disturbances, prediction of electrical coupling risks, and coordinated scheduling of pump operation and compensation devices to actively maintain system impedance stability and safely navigate transient processes has become a core technical problem urgently needing to be solved in this field. In view of this, we propose an online configuration and dynamic control method for low-pressure reactive power compensation systems in hydraulic pumping stations. Summary of the Invention

[0005] The purpose of this invention is to provide an online configuration and dynamic control method for a low-pressure reactive power compensation system in a water conservancy pumping station, so as to solve the technical problems of traditional methods that cannot actively cope with the risk of system impedance change and resonance caused by water hammer impact, and lack the ability to coordinate and control the pump and the compensation device.

[0006] To solve the above-mentioned technical problems, the present invention provides the following technical solution: a method for online configuration and dynamic control of a low-pressure reactive power compensation system for a water conservancy pumping station, comprising the following steps: S1: Online construction and updating of the hydraulic-electric coupling dynamic model of the pumping station; the hydraulic-electric coupling dynamic model at least characterizes the hydraulic impedance characteristics of the pumping station network, the harmonic generation characteristics of the pump frequency conversion drive system, and the output impedance characteristics of the low-voltage reactive power compensation system including the static var generator and the active filter. S2: Based on the aforementioned hydraulic-electric coupling dynamic model, for pump start-up and shutdown and valve adjustment operations that induce hydraulic shock and electrical disturbance during pump station operation, predict the system equivalent impedance change path that will be caused by them, and combine with the preset impedance safety boundary to plan a safe impedance trajectory that smoothly transitions from the current operating state to the target state; the planning of the safe impedance trajectory aims to minimize the system equivalent impedance change rate and avoid the impedance safety boundary throughout the entire process; S3: Based on the safety impedance trajectory, generate a coordinated control parameter sequence for the water pump, valve, and low-pressure reactive power compensation system; the coordinated control parameter sequence includes instructions for coordinating the start-up and shutdown of the water pump or the action sequence of the valve, and instructions for dynamically adjusting the control mode and control parameters of the static var generator and the active filter. S4: While performing pump start / stop or valve adjustment operations, execute the coordinated control parameter sequence to coordinate the output impedance of the low-pressure reactive power compensation system with the dynamic changes in the pump station system impedance, track the safety impedance trajectory, suppress system resonance during hydraulic impact, and achieve dynamic reactive power compensation.

[0007] This invention achieves a fundamental shift from passive response to active defense by constructing a hydraulic-electrical coupled dynamic model and pre-planning a smooth "safe impedance trajectory" that avoids resonance risk zones for critical pump station operations (such as pump group start-up and shutdown). Traditional methods, when dealing with water hammer and other impacts, can only provide delayed remedies based on existing electrical degradation (such as voltage drops and harmonic exceedances), and the control targets of each device are isolated, making it impossible to anticipate and control system-level risks (such as resonance) that may arise from their interactions. This method treats the system impedance change caused by water hammer as a predictable and plannable process. It predicts the impedance change path caused by operations through a coupled model and optimizes the generation of the optimal operation timing and impedance evolution path with the dual objectives of "minimizing the rate of impedance change" and "avoiding resonance zones throughout the entire process." This allows the system to plan the theoretically smoothest and safest crossing route before facing the most severe transient processes, thus avoiding the possibility of actively "entering" the resonance danger zone due to improper operation timing or compensation response mismatch. It elevates the system safety control from "post-accident remediation" to "pre-operation prevention," fundamentally solving the core problem of transient resonance risk.

[0008] Preferably, step S1 specifically includes: S101: Real-time collection of hydraulic operation data such as pipeline pressure, valve opening, pump speed and flow rate, as well as bus voltage, current, harmonic components and electrical operation data of the low-voltage reactive power compensation system through the monitoring, control and data acquisition system; S102: Based on hydraulic operation data, the hydraulic impedance frequency characteristics of the pipeline network under the current operating conditions are calculated using a system identification method. ; S103: Based on electrical operation data, and combined with the known topology and control structure of the static var generator and active filter in the low-voltage reactive power compensation system, determine its current output impedance frequency characteristics. ; S104: The hydraulic impedance frequency characteristics The harmonic generation characteristics and the output impedance frequency characteristics are coupled and correlated to form the hydraulic-electric coupling dynamic model; Among them, the hydraulic impedance frequency characteristics Defined at frequency Below, pipeline pressure fluctuations With traffic fluctuations The ratio: .

[0009] Preferably, in step S102, the hydraulic impedance frequency characteristics are calculated using a system identification method, specifically as follows: The dynamic pressure and flow data collected by the monitoring, control and data acquisition system during valve regulation or pump start-up and shutdown are analyzed, or the pressure transfer function of the pipeline network is identified by using frequency domain analysis or time domain fitting algorithms, and its hydraulic impedance frequency characteristics are derived by injecting a preset small pressure or flow disturbance into the pipeline network and collecting response data. Among them, based on the collected input-output data pairs The parameterized transfer function model is fitted using the least squares method. The identification process minimizes the following loss function. : ; In the formula, The parameter vector of the transfer function model to be identified; For at any time Actual measured pressure response value; For parameter-based The model at time Predicted pressure response value; This represents the total number of data points used for identification.

[0010] Preferably, in step S2, when the operation involves the sequential start-up and shutdown of multiple water pumps, the planning of the safety impedance trajectory specifically includes: S201: Obtain the initial plan for the predetermined pump start / stop sequence and time interval; S202: Taking the hydraulic-electric coupling dynamic model as the object, with the goal of minimizing the rate of change of the system's equivalent impedance and keeping it within the impedance safety boundary throughout the entire process, optimize the precise start-up or shutdown time of each pump and the time interval between adjacent operations. S203: The optimized pump operation timing is mapped as a system equivalent impedance trajectory that evolves continuously on the impedance frequency-time plane, which is used as the safety impedance trajectory. The optimization solution process is described as the following constrained optimization problem: ; The constraints are: , ; , ; In the formula, To optimize the objective function value; For optimization Secondary pump operation time vector. ; In frequency and time The equivalent impedance of the system under the following conditions; For frequency The following impedance safety zone; The start and end times of the transition process are considered for optimization. For the frequency range of interest; For the first Next and first The time interval between operations. ; and These are the physical upper and lower limits of the operation time interval.

[0011] Preferably, in step S2, the preset impedance safety boundary is determined in the following way: Based on the aforementioned hydraulic-electric coupling dynamic model, the frequency characteristics of hydraulic impedance are compared and analyzed. The output impedance frequency characteristics of the low-voltage reactive power compensation system By calculating the impedance ratio To identify dangerous frequency regions close to -1; Around the identified danger frequency points Set a safety margin The impedance safety boundary is formed on the impedance frequency plane. Its definition is: ; In the formula, The bandwidth considered around the critical frequency point.

[0012] Preferably, step S3 specifically includes: S301: Discretize the safety impedance trajectory into multiple consecutive impedance state nodes on the time axis; S302: For each impedance state node, the reactive power output reference value of the static var generator in the low-voltage reactive power compensation system is obtained by inversely solving the hydraulic-electric coupling dynamic model to track the impedance state of that node. and the harmonic compensation command reference value for active filters. ; S303: Based on the reactive power output reference value and the harmonic compensation instruction reference value, and combined with the internal control strategy of the static var generator and the active filter, generate the corresponding controller parameter adjustment instruction; S304: Arrange the operation timing instructions of the water pump and valve, as well as the controller parameter adjustment instructions, in chronological order to form the coordinated control parameter sequence.

[0013] Preferably, in step S303, generating the controller parameter adjustment instruction specifically includes: The operating mode of the active filter is dynamically configured according to the evolution stage of the safety impedance trajectory. During periods of drastic change in the system's equivalent impedance, the active filter is configured in a hybrid compensation mode that primarily suppresses impulsive harmonics while secondarily providing dynamic reactive power support. At this time, its output current references... And its current loop controller parameters are adjusted to , In the formula, The dynamic weighting coefficients for reactive power compensation components. ; , For a moment Proportional and integral parameters of the lower current control loop; , These are the rated parameters of the controller; Indicates the gain boost factor. .

[0014] During the phase when the system's equivalent impedance changes steadily, the active filter is configured to balance harmonic compensation and reactive power compensation.

[0015] Preferably, in step S4, tracking the safety impedance trajectory specifically includes: S401: During operation, the actual system electrical quantities are monitored in real time through the monitoring, control and data acquisition system; S402: Based on real-time monitored electrical quantities, estimate the actual system equivalent impedance at the current moment online. ; S403: Equivalent impedance of the actual system The reference impedance state at the corresponding moment in the safety impedance trajectory The comparison is performed, and if the deviation exceeds a preset threshold, an online correction mechanism is triggered. S404: The online correction mechanism fine-tunes the subsequent controller parameter adjustment instructions in the cooperative control parameter sequence in real time according to the deviation, so that the actual system equivalent impedance reconverges to the safe impedance trajectory.

[0016] Preferably, the online correction mechanism is implemented using a model predictive control framework, specifically as follows: The hydraulic-electric coupling dynamic model is used as the prediction model. Based on the predicted equivalent impedance of the actual system within a finite future time window Compared with reference trajectory Minimizing the deviation is the optimization objective, and controller parameter adjustment commands are used. To optimize the variables, a rolling optimization solution is performed; Each control cycle solves the following optimization problem: ; The constraints are: ; ; ; ; In the formula, Indicates the current moment Regarding the future The predicted value of the system impedance at time; For the future The reference impedance trajectory value at time; Indicating a view on the future The predicted value of the control variable is controlled at all times; To control the increment; The control increment to be optimized; and This represents a positive definite matrix weighted by the changes in tracking error and control increment, respectively. To predict the length of the time domain; To control the length of the time domain, ; , and , Physical constraints for control variables and their increments; only the control increments from the first step are considered. Applied to the system.

[0017] An online configuration and dynamic control system, comprising: The model management module is used for online construction and updating of dynamic models of hydraulic-electric coupling in pumping stations; The trajectory planning module plans the safety impedance trajectory based on the hydraulic-electric coupling dynamic model and preset operations; The cooperative sequence generation module generates the cooperative control parameter sequence based on the safety impedance trajectory; The closed-loop execution module is used to coordinate and control the water pump, valves, and the low-pressure reactive power compensation system to execute the coordinated control parameter sequence and achieve trajectory tracking. The model management module, trajectory planning module, collaborative sequence generation module, and closed-loop execution module are integrated into the upper-layer application server or a separate collaborative controller of the supervision, control, and data acquisition system.

[0018] 1. This invention achieves a fundamental shift from passive response to active defense by constructing a hydraulic-electrical coupled dynamic model and, based on this model, pre-planning a smooth "safe impedance trajectory" that avoids resonance risk zones for critical pump station operations (such as pump group start-up and shutdown). Traditional methods, when dealing with water hammer and other impacts, can only provide delayed remedies based on existing electrical degradation (such as voltage drops and harmonic exceedances), and the control targets of each device are isolated, making it impossible to anticipate and control the system-level risks (such as resonance) that may be caused by their interactions. This method treats the system impedance change caused by water hammer as a predictable and plannable process. It predicts the impedance change path caused by operations through a coupled model and optimizes the generation of the optimal operation timing and impedance evolution path with the dual objectives of "minimizing the rate of impedance change" and "avoiding resonance zones throughout the entire process." This allows the system to plan the theoretically smoothest and safest crossing route before facing the most severe transient processes, thus avoiding the possibility of actively "entering" the resonance danger zone due to improper operation timing or compensation response mismatch. It elevates the system safety control from "post-accident remediation" to "pre-operation prevention," fundamentally solving the core problem of transient resonance risk.

[0019] 2. This invention also generates a coordinated control parameter sequence across pumps, valves, and various reactive power compensation devices based on the aforementioned safe impedance trajectory. This achieves dynamic, integrated, and precise control of multiple actuators in the "water-mechanical-electrical" system, solving the problem of how to accurately track and execute the planned trajectory. Safe trajectory planning alone is insufficient to guarantee the safety of the actual system; the key lies in how to ensure the impedance of the actual system dynamically and accurately follows the planned trajectory. This invention decomposes the macroscopic impedance trajectory target into microscopic, time-sequentially corresponding specific equipment control commands through reverse solving of the coupling model. These commands include the precise start and stop times of the pumps, the valve operating rhythm, and the dynamic adjustment sequence of the control modes and parameters of the SVG and APF. Specifically, for the APF, a strategy is proposed to dynamically switch its operating mode and controller parameters based on the severity of impedance changes, prioritizing harmonic suppression speed and capability during peak impedance phases. This deep collaborative control mechanism ensures that, during dynamic processes, the output characteristics of the compensation device can match the expected changes in system impedance in real time and accurately, forming a closed loop of "hydraulic operation causing disturbances, electrical compensation synchronously canceling them out and guiding the impedance to evolve along a predetermined path." This allows the theoretical safety trajectory to be faithfully executed in complex real physical systems, thereby consolidating and realizing proactive safety defense capabilities.

[0020] 3. This invention also endows the system with strong robustness and self-learning evolution capabilities in the face of model uncertainty, equipment aging, and unknown disturbances by introducing an online correction mechanism based on model predictive control and a historical strategy library learning function. Although model-based planning and collaborative control constitute the main framework, real-world systems always suffer from model errors, component characteristic drift, and unmodeled disturbances. Therefore, during the tracking execution phase, this invention monitors impedance deviation in real time and triggers an online correction mechanism. This mechanism uses a model predictive control framework for rolling optimization and feedback correction, enabling real-time fine-tuning of subsequent control commands and dynamically pulling the system state back on track, significantly enhancing its anti-interference capability. Simultaneously, by establishing a historical event strategy library, the system can accumulate optimal control experience under different operating scenarios, enabling the reuse and optimization of experience, allowing the control strategy to continuously improve itself over time. These two layers of design work together to ensure that the active defense and collaborative control system is not a fragile "open-loop" preset, but a highly adaptable and reliable closed-loop system with complete intelligence of "perception-decision-execution-learning". This ensures accurate dynamic tracking performance in long-term complex operating environments and further improves the overall system's intelligence level and long-term operational reliability. Attached Figure Description

[0021] Figure 1 This is a flowchart illustrating the overall method of the present invention; Figure 2 This is a detailed flowchart of step S1 in this invention; Figure 3 This is a detailed flowchart of step S2 in the present invention; Figure 4 This is a detailed flowchart of step S3 in this invention; Figure 5 This is a schematic diagram of the system architecture of the present invention. Detailed Implementation

[0022] Example 1: As Figures 1 to 4 As shown, the present invention relates to an online configuration and dynamic control method for a low-pressure reactive power compensation system in a water conservancy pumping station, comprising the following steps: S1: Online construction and updating of the hydraulic-electric coupling dynamic model of the pumping station; the model at least characterizes the hydraulic impedance characteristics of the pumping station network, the harmonic generation characteristics of the pump frequency conversion drive system, and the output impedance characteristics of the low-voltage reactive power compensation system including the static var generator and the active filter. In an embodiment of the present invention, the online construction and updating of the hydraulic-electric coupling dynamic model of the pumping station in step S1 specifically includes: S101: Real-time collection of hydraulic operation data such as pipeline pressure, valve opening, pump speed and flow rate, as well as bus voltage, current, harmonic components and electrical operation data of the low-voltage reactive power compensation system through the monitoring, control and data acquisition system; S102: Based on the hydraulic operation data, the hydraulic impedance frequency characteristics of the pipeline network under the current operating conditions are calculated using a system identification method. In an embodiment of the present invention, the calculation of hydraulic impedance frequency characteristics using a system identification method in step S102 specifically includes: The dynamic pressure and flow data collected by the monitoring, control and data acquisition system during valve regulation or pump start-up and shutdown are analyzed, or the pressure transfer function of the pipeline network is identified by using frequency domain analysis or time domain fitting algorithms, and its hydraulic impedance frequency characteristics are derived.

[0023] Among them, based on the collected input-output data pairs A parameterized transfer function model is fitted using the least squares method. Its frequency domain expression is This ensures that the model output and the measured data are optimally matched in the least-squares sense. The hydraulic impedance... The identification process minimizes the following loss function, which can be derived from the transfer function and pipeline characteristics. : ; In the formula: The loss function (scalar) identified for the parameters; The parameter vector of the transfer function model to be identified; For at any time The actual measured pressure response value (scalar); For parameter-based The model at time Predicted pressure response value (scalar); This represents the total number of data points used for identification.

[0024] Operational logic: This formula describes the core process of system identification—minimizing the sum of squared errors (loss function) between the model's predicted output and the actual measured data. To find the optimal model parameters. Essentially, it aims to make the mathematical model "fit" the dynamic behavior of the actual system as closely as possible, thereby obtaining a reliable transfer function. and the resulting hydraulic resistance This data-driven approach automatically adapts to system characteristic drift caused by factors such as pipe scaling, valve performance changes, and pump performance degradation, enabling online self-learning and self-updating of hydraulic impedance characteristics. This overcomes the problem of gradual distortion in traditional fixed models, ensuring the long-term accuracy of coupled dynamic models and providing a continuously reliable foundation for safe control.

[0025] S103: Based on the electrical operation data, and combined with the known topology and control structure of the static var generator and active filter in the low-voltage reactive power compensation system, determine its current output impedance frequency characteristics. S104: The hydraulic impedance frequency characteristics, the harmonic generation characteristics, and the output impedance frequency characteristics are coupled and correlated to form the hydraulic-electric coupling dynamic model.

[0026] Among them, the hydraulic impedance frequency characteristics Defined at frequency Below, pipeline pressure fluctuations With traffic fluctuations The ratio, in its complex form, represents the relationship between amplitude and phase: ; In the formula: For the pipeline network at frequency Hydraulic resistance (complex number) under the current. For frequency The pipeline pressure fluctuation component (complex number). For frequency The complex component of the pipeline flow fluctuation. Operational Logic: This formula defines the hydraulic impedance of the pipe network at a specific frequency *f*, i.e., the resistance characteristic of the pipe network to alternating flow disturbances, characterized by the complex ratio of pressure fluctuations to flow fluctuations. Its amplitude represents the magnitude of the resistance, and the phase represents the lag or lead relationship between pressure and flow fluctuations. This is the fundamental physical relationship for constructing the hydraulic-electric coupling model. By identifying this relationship online, the system can perceive the dynamic characteristics of the pipe network itself in real time, rather than relying on fixed, offline hydraulic calculation parameters. This provides accurate hydraulic-side input for subsequent accurate prediction of electrical disturbances caused by water hammer, enabling the entire control strategy to be based on real physical dynamics, significantly improving the model's ability to characterize actual working conditions and the targeted nature of control.

[0027] S2: Based on the hydraulic-electric coupling dynamic model, for the pump start-up and shutdown and valve adjustment operations that induce hydraulic shock and electrical disturbance during pump station operation, predict the system equivalent impedance change path that will be caused by them, and combine with the preset impedance safety boundary to plan a safe impedance trajectory that smoothly transitions from the current operating state to the target state. In an embodiment of the present invention, the pump start-up and shutdown and valve adjustment operations for water pumps that induce hydraulic shock and electrical disturbances during pump station operation described in step S2 specifically include: starting or stopping a single high-power water pump, sequential starting and stopping of multiple water pumps, and rapid closing or opening of valves.

[0028] In an embodiment of the present invention, when the operation is a sequential start-up and shutdown operation of multiple water pumps, step S2, which involves planning a safe impedance trajectory for a smooth transition from the current operating state to the target state, specifically includes: S201: Obtain the initial plan for the predetermined pump start / stop sequence and time interval; S202: Taking the hydraulic-electric coupling dynamic model as the object, with the goal of minimizing the rate of change of the system's equivalent impedance and keeping it within the impedance safety boundary throughout the entire process, optimize the precise start-up or shutdown time of each pump and the time interval between adjacent operations. S203: The optimized pump operation timing is mapped as a system equivalent impedance trajectory that evolves continuously on the impedance frequency-time plane, which is used as the safety impedance trajectory.

[0029] The optimization solution process is described as a constrained optimization problem with an objective function. Aimed at minimizing the system's equivalent impedance throughout the transition period The rate of change, and satisfying the impedance safety boundary constraints. : ; The constraints are: , ; , ; In the formula: To optimize the objective function value, the value represents the degree of drastic change in total impedance (scalar). For optimization Secondary pump operation time vector. ; In frequency and time The system equivalent impedance (complex number) under the following conditions. For frequency Impedance safety forbidden zones (complex set); The start and end times of the transition process are considered for optimization. For the frequency range of interest; For the first Next and first The time interval between operations. ; and These are the physical upper and lower limits allowed for the operation time interval; Operational logic: This formula constructs a multi-objective constrained optimization problem. Its core is to satisfy the impedance safety boundary (…). Given the physical constraints of time intervals, find the optimal sequence of operation times. This makes the system's equivalent impedance during the entire transition period... Over time The goal is to minimize the rate of change (measured by the square of the integral). The goal is to find the smoothest impedance transition trajectory. By solving this optimization problem, the planning of the operating timing can be transformed from an experience-based engineering problem into a quantifiable and solvable mathematical problem. The output safe impedance trajectory mathematically guarantees the theoretically optimal smoothness of the transition process, fundamentally avoiding the risk of actively "entering" the resonance danger zone due to improper operating timing, and realizing a leap from "experience-based avoidance" to "theoretical navigation".

[0030] In an embodiment of the present invention, the preset impedance safety boundary mentioned in step S2 is determined in the following manner: By comparing and analyzing the frequency characteristics of the hydraulic impedance in the hydraulic-electric coupling dynamic model with the frequency characteristics of the output impedance of the low-voltage reactive power compensation system, dangerous frequency regions where parallel or series resonance may occur can be identified. A safety margin is set around the dangerous frequency region, and an impedance safety boundary is formed on the impedance frequency plane that prohibits the equivalent impedance trajectory of the system from crossing it.

[0031] The critical frequency region is determined by analyzing the Nyquist curve of the system's open-loop transfer function or by calculating the impedance ratio. To identify this, a ratio close to -1 indicates a risk of resonance. ; In the formula: In frequency The ratio of the hydraulic impedance to the output impedance of the compensation system (complex number).

[0032] For low-voltage reactive power compensation systems at frequency The equivalent output impedance (complex number) is given below.

[0033] Wherein, the impedance safety boundary It can be defined as a dangerous frequency point Centered on, with a certain safety margin Restricted Area: ; In the formula: In frequency Nearby impedance safety restricted areas (complex set); For the identified dangerous (resonant) frequency points; The set safety margin factor (scalar, ); The bandwidth considered around the critical frequency point; Operational logic: First formula The system's impedance ratio is defined for determining resonance risk. According to impedance stability theory, when this ratio approaches -1, the system is at risk of resonance (oscillation divergence). The second formula defines the range around the danger frequency point. impedance safety boundary It is a plane in which... Centered on, with For the radius (considering safety margin) A circular region, in and around this frequency band Internally, system impedance is prohibited. Enter. Through quantitative analysis. And dynamically set This transforms the abstract "resonance risk" into a clear and calculable "no-go zone" on the impedance complex plane. This provides clear mathematical constraints for planning the safety trajectory and enables the online control system to perform real-time, quantitative assessment and early warning of resonance risk, rather than relying solely on passive protection based on the consequences of faults such as overcurrent and overvoltage, thus greatly enhancing the system's proactive safety defense capabilities.

[0034] S3: Based on the safety impedance trajectory, generate a coordinated control parameter sequence for the water pump, valve, and low-pressure reactive power compensation system; the coordinated control parameter sequence includes instructions for coordinating the start-up and shutdown of the water pump or the action sequence of the valve, and instructions for dynamically adjusting the control mode and control parameters of the static var generator and the active filter. In an embodiment of the present invention, the step S3 of generating the coordinated control parameter sequence of the water pump, valve, and low-pressure reactive power compensation system specifically includes: S301: Discretize the safety impedance trajectory into multiple consecutive impedance state nodes on the time axis; S302: For each impedance state node, the reactive power output reference value of the static var generator in the low-voltage reactive power compensation system and the harmonic compensation command reference value of the active filter are obtained by inverse solution based on the hydraulic-electric coupling dynamic model to track the impedance state of the node. S303: Based on the reactive power output reference value and the harmonic compensation instruction reference value, and combined with the internal control strategies of the static var generator and the active filter, generate corresponding controller parameter adjustment instructions. The controller parameters include at least one or a combination of proportional-integral controller parameters and virtual impedance parameters. In an embodiment of the present invention, generating the corresponding controller parameter adjustment instruction in step S303 specifically includes: The operating mode of the active filter is dynamically configured according to the evolution stage of the safety impedance trajectory. During the stage of drastic changes in the system's equivalent impedance, the active filter is configured as a hybrid compensation mode that primarily suppresses impulsive harmonics and secondarily provides dynamic reactive power support. During the phase when the system's equivalent impedance changes steadily, the active filter is configured to balance harmonic compensation and reactive power compensation.

[0035] Among them, the output current reference of the active filter Harmonic compensation components With reactive power compensation component Synthesis. Its internal controller's proportional-integral parameters. , The settings are dynamically adjusted based on the operating mode. In hybrid compensation mode, a higher harmonic current tracking bandwidth factor is set. Its current reference and controller parameters follow: , ; , ; In the formula: For the active filter at time The total output current reference value; This is a reference value for harmonic current compensation. This is the reference value for fundamental frequency reactive current compensation. The dynamic weighting coefficient for reactive power compensation components is between 0 and 1; , For a moment Proportional and integral parameters of the lower current control loop; , These are the rated (basic) parameters of the controller; This represents the gain boost factor set during the impulsive harmonic suppression stage to improve harmonic tracking speed. ); Operational Logic: These formulas describe the specific control law of the active filter in hybrid compensation mode. Total Reference Current Harmonic components and after weighting coefficients Adjusted reactive component Synthesis. During the impact phase (where harmonics need to be suppressed rapidly), by reducing... Reduce reactive power output load while increasing controller gain. (make , (Increased proportionally) to improve the tracking speed and accuracy of harmonic currents. This is achieved by introducing dynamic weights. and gain coefficient This system achieves adaptive and coordinated switching between the active filter's operating mode and the controller parameters. During the most vulnerable impact phase of the system, harmonic suppression is prioritized and strengthened while reactive power support is also considered; during the stable phase, equalization compensation is restored. This dynamic resource allocation strategy enables a single device to intelligently undertake different compensation tasks at different stages, improving device utilization efficiency and the transient performance of the overall system.

[0036] S304: Arrange the operation timing instructions of the water pump and valve, as well as the controller parameter adjustment instructions, in chronological order to form the coordinated control parameter sequence.

[0037] The reverse solution process described in step S302 involves obtaining the desired system equivalent impedance. The reference command for the compensation device is derived. This process is based on a coupling model, and the harmonic current reference of the active filter is obtained by solving the following relationship. and the fundamental reactive current reference of the static var generator : ; In the formula: For at any time The desired system equivalent impedance (complex number, representing a point on the safety trajectory); This represents the mapping function defined by the hydraulic-electric coupling dynamic model, from the output of the compensation device to the equivalent impedance of the system, which implicitly includes the hydraulic impedance of the pipe network. Equivalent output impedance of compensation device The parallel, series, and other connection relationships are described. The specific form of the mapping function depends on the specific electrical wiring and topology of the pump station. For at any time The active filter needs to output a harmonic current compensation reference command; For at any time The static var generator needs to output a fundamental reactive current reference command. Operational logic: This formula describes the expected system equivalent impedance. Output commands required for inverse solving compensation device and The inverse mapping process. Function This represents the forward relationship defined by the coupled dynamic model constructed in step S1 (i.e., calculating the system impedance given a compensation command). The inverse solution is the solution of the inverse problem of this equation to obtain the precise control commands needed to track the desired impedance trajectory. This inverse solution process is the key bridge connecting "planning" and "execution." It ensures that the control commands calculated for tracking the ideal safety trajectory are accurate and feasible at the physical model level. This achieves a closed-loop decomposition from the macroscopic impedance trajectory target to the microscopic device control commands, giving the generation of the entire cooperative control sequence a solid model foundation and guaranteeing that the theoretical plan can be accurately executed.

[0038] In an embodiment of the present invention, step S3 further includes: S305: Based on historical hydraulic impact event data, establish a strategy library containing different operation types, intensities, and corresponding optimal coordinated control parameter sequences; S306: Match the type and intensity of the operation to be executed with the strategy library. If the match is successful, directly call the historical best cooperative control parameter sequence as the basis and make corrections based on the slight differences in the current system state. If the match is unsuccessful, execute steps S301 to S304 to generate a new cooperative control parameter sequence and store the new sequence and its effect data in the strategy library.

[0039] S4: While performing the pump start / stop or valve adjustment operation, execute the coordinated control parameter sequence to coordinate the output impedance of the low-pressure reactive power compensation system with the dynamic change of the pump station system impedance, track the safety impedance trajectory, suppress system resonance during hydraulic impact and achieve dynamic reactive power compensation.

[0040] In an embodiment of the present invention, step S4, which involves tracking the safety impedance trajectory, specifically includes: S401: During the pump start-up / stop or valve adjustment operation, the actual system electrical quantities are monitored in real time by the monitoring, control and data acquisition system. S402: Based on the real-time monitored electrical quantities, estimate the actual system equivalent impedance at the current moment online; In step S402, the equivalent impedance of the actual system is estimated online. Using recursive least squares or similar online parameter estimation algorithms, based on real-time measured bus voltage... With total current The perturbation components are processed.

[0041] S403: Compare the actual system equivalent impedance with the reference impedance state at the corresponding moment in the safety impedance trajectory. If the deviation exceeds a preset threshold, trigger the online correction mechanism. In an embodiment of the present invention, the online correction mechanism is implemented using a model predictive control framework, specifically as follows: Using the aforementioned hydraulic-electric coupling dynamic model as the prediction model, with the goal of minimizing the deviation between the actual system's equivalent impedance and the reference impedance trajectory within a future finite time window, and with the controller parameter adjustment command as the optimization variable, rolling optimization is performed, and the latest control command obtained from the solution is applied in real time.

[0042] Let's assume at the current time The prediction time domain is Control time domain is This rolling optimization problem is solved once in each control cycle, and its nth... The optimization problem of the step is expressed as: ; The constraints are: ; ; ; ; Among them, only the control increment of the first step is included. Applied to the system.

[0043] In the formula: Indicates the current moment Regarding the future The predicted value of the system impedance at time; For the future The reference impedance trajectory value at time; For control variables (i.e., controller parameters); Indicating a view on the future The predicted values ​​of control variables (such as controller parameters) at any given time; To control the increment; The control increment to be optimized; A discretized dynamic prediction model for hydraulic-electric coupling; and This represents a positive definite matrix weighted by the changes in tracking error and control increment, respectively. To predict the length of the time domain; To control the length of the time domain ( ); , and , Physical constraints for controlling variables and their increments; Operational Logic: This formula describes a standard Model Predictive Control (MPC) rolling optimization problem. At each current time step... The algorithm is based on the model Predicting the future Step system impedance And by optimizing the future Step control increment (i.e., the adjustment of controller parameters) to make the predicted trajectory as close as possible to the reference trajectory. It also penalizes excessively large control changes. After optimization, only the first step of the control increment is implemented. The system then re-measures, predicts, and optimizes at the next moment, forming a closed loop of "rolling optimization and feedback correction." The core advantage of using the MPC framework to handle the trajectory tracking problem lies in the combination of feedforward and feedback in rolling optimization. It utilizes the model for forward prediction, making control decisions in advance to cope with foreseeable dynamics; simultaneously, each step performs feedback correction based on the latest actual measurements to overcome model mismatch and unknown disturbances. This mechanism enables the system to dynamically and robustly pull back to a safe trajectory even when there are deviations between actual water hammer impacts and model predictions, significantly enhancing the robustness and reliability of the entire solution in complex real-world environments.

[0044] S404: The online correction mechanism fine-tunes the subsequent controller parameter adjustment instructions in the cooperative control parameter sequence in real time according to the deviation, so that the actual system equivalent impedance reconverges to the safe impedance trajectory.

[0045] Example 2: Figure 5 As shown: An online configuration and dynamic control system, comprising: The model management module is used to build and update the hydraulic-electric coupling dynamic model of the pumping station online. The trajectory planning module is used to plan the safety impedance trajectory based on the model and preset operations; A cooperative sequence generation module is used to generate the cooperative control parameter sequence based on the safety impedance trajectory; The closed-loop execution module is used to coordinate and control the water pump, valves, and the low-pressure reactive power compensation system to execute the coordinated control parameter sequence and achieve trajectory tracking. The model management module, trajectory planning module, collaborative sequence generation module, and closed-loop execution module are integrated into the upper-layer application server or a separate collaborative controller of the supervision, control, and data acquisition system.

[0046] In another embodiment of the present invention, the closed-loop execution module includes: The instruction distribution unit is used to send the pump and valve operation instructions in the coordinated control parameter sequence to the corresponding pump control system and valve actuator through the monitoring control and data acquisition system. The parameter configuration unit is used to directly send the controller parameter adjustment instructions in the coordinated control parameter sequence to the local controller of the static var generator and the active filter through the industrial communication network. The status monitoring and feedback unit is used to collect the system status in real time through the supervision, control and data acquisition system and provide it to the online correction mechanism.

[0047] As another embodiment of the present invention, the system further includes a digital twin simulation module, which is connected to the model management module and is used to provide a high-precision virtual simulation environment when the trajectory planning module and the cooperative sequence generation module are performing offline testing or training, so as to verify the system response under different operation and cooperative control strategies and optimize the hydraulic-electric coupling dynamic model and control parameters.

[0048] Example 3: The invention was applied and verified in a large irrigation pumping station. This pumping station is equipped with four centrifugal pumps, each with a rated power of 560kW, all driven by variable frequency drives (VFDs). A static var generator (SVG) with a capacity of ±300kVar and an active power filter (APF) with a capacity of 150A are installed on the low-voltage bus side. This example uses the sequential startup of pump number 4 and pump number 3 (with a planned interval of 30 seconds) as a typical water hammer induced condition, comparing the system response under the method of this invention with that under a traditional fixed-sequence startup method.

[0049] The SCADA system was used to acquire basic pipeline parameters and historical operating data. Before the test, the system actively performed a small-amplitude valve disturbance test, collecting pressure and flow response data. The least squares method was used to identify the hydraulic impedance characteristics of the current pipeline network in the 0.1-100Hz frequency band. Simultaneously, based on the nameplate parameters and control architecture of the SVG and APF, their output impedance models are determined. Coupling analysis revealed a potential impedance resonance risk point near 23.5 Hz.

[0050] II. Safety Impedance Trajectory Planning and Cooperative Sequence Generation: For the operation of "pump 4 starts → wait Δt → pump 3 starts", the system of this invention performs trajectory planning. Traditional operating condition: A fixed 30-second start interval is used. Optimized operating condition of this invention: The optimization objective is to achieve the smoothest change in the system's equivalent impedance while avoiding the impedance forbidden zone near 23.5Hz throughout the process. The optimization result is: after pump 4 starts, pump 3 starts after a delay of 42.7 seconds, and the corresponding SVG reactive power output curve and APF control parameters (mode, ...) are generated. , Adjust the sequence.

[0051] III. Comparison and Analysis of Experimental Results Table 1 Comparison of Key Operating Parameters

[0052] Table 2 Comparison of main spectrum analysis (0.5 seconds after the second pump starts)

[0053] The experimental data examples demonstrate that, compared to traditional fixed-sequence control methods, the hydraulic-electric coupling dynamic modeling, safety impedance trajectory planning, and multi-device collaborative control method described in this invention can: Effective suppression of resonance: By planning a safe trajectory and dynamically adjusting the compensation device, the harmonic amplification factor at dangerous frequency points is suppressed from 3.2 times to 1.1 times, fundamentally avoiding resonance accidents.

[0054] Significantly improves transient stability: Reduces the most severe voltage drop from 15.8% to 8.2%, shortens recovery time by more than half, and greatly improves the robustness of the pump station power grid under impact.

[0055] Optimized harmonic mitigation effect: Under the dynamic and coordinated control of APF, the content of major characteristic harmonics is reduced by more than 50%, and the power quality is significantly improved.

[0056] Achieving intelligent collaboration: The effectiveness of the complete closed loop from hydraulic operation prediction and electrical risk assessment to collaborative control of actuators was verified, providing a reliable technical solution for the safe, efficient and intelligent operation of pumping stations.

[0057] The embodiments disclosed in this invention are preferred embodiments, but are not limited thereto. Those skilled in the art can easily understand the spirit of this invention based on the above embodiments and make different extensions and variations, but as long as they do not depart from the spirit of this invention, they are all within the protection scope of this invention.

Claims

1. A method for online configuration and dynamic control of a low-pressure reactive power compensation system for a water conservancy pumping station, characterized in that, Includes the following steps: S1: Online construction and updating of the hydraulic-electric coupling dynamic model of the pumping station; the hydraulic-electric coupling dynamic model at least characterizes the hydraulic impedance characteristics of the pumping station network, the harmonic generation characteristics of the pump frequency conversion drive system, and the output impedance characteristics of the low-voltage reactive power compensation system including the static var generator and the active filter. S2: Based on the aforementioned hydraulic-electric coupling dynamic model, for pump start-up and shutdown and valve adjustment operations that induce hydraulic shock and electrical disturbance during pump station operation, predict the system equivalent impedance change path that will be caused by them, and combine with the preset impedance safety boundary to plan a safe impedance trajectory that smoothly transitions from the current operating state to the target state; the planning of the safe impedance trajectory aims to minimize the system equivalent impedance change rate and avoid the impedance safety boundary throughout the entire process; S3: Based on the safety impedance trajectory, generate a coordinated control parameter sequence for the water pump, valve, and low-pressure reactive power compensation system; the coordinated control parameter sequence includes instructions for coordinating the start-up and shutdown of the water pump or the action sequence of the valve, and instructions for dynamically adjusting the control mode and control parameters of the static var generator and the active filter. S4: While performing pump start / stop or valve adjustment operations, execute the coordinated control parameter sequence to coordinate the output impedance of the low-pressure reactive power compensation system with the dynamic changes in the pump station system impedance, track the safety impedance trajectory, suppress system resonance during hydraulic impact, and achieve dynamic reactive power compensation.

2. The method for online configuration and dynamic control of a low-pressure reactive power compensation system for a water conservancy pumping station according to claim 1, characterized in that, Step S1 specifically includes: S101: Real-time collection of hydraulic operation data such as pipeline pressure, valve opening, pump speed and flow rate, as well as bus voltage, current, harmonic components and electrical operation data of the low-voltage reactive power compensation system through the monitoring, control and data acquisition system; S102: Based on hydraulic operation data, the hydraulic impedance frequency characteristics of the pipeline network under the current operating conditions are calculated using a system identification method. ; S103: Based on electrical operation data, and combined with the known topology and control structure of the static var generator and active filter in the low-voltage reactive power compensation system, determine its current output impedance frequency characteristics. ; S104: The hydraulic impedance frequency characteristics The harmonic generation characteristics and the output impedance frequency characteristics are coupled and correlated to form the hydraulic-electric coupling dynamic model; Among them, the hydraulic impedance frequency characteristics Defined at frequency Below, pipeline pressure fluctuations With traffic fluctuations The ratio: .

3. The method for online configuration and dynamic control of a low-pressure reactive power compensation system for a water conservancy pumping station according to claim 2, characterized in that, In step S102, the hydraulic impedance frequency characteristics are calculated using a system identification method, specifically as follows: The dynamic pressure and flow data collected by the monitoring, control and data acquisition system during valve regulation or pump start-up and shutdown are analyzed, or the pressure transfer function of the pipeline network is identified by using frequency domain analysis or time domain fitting algorithms, and its hydraulic impedance frequency characteristics are derived by injecting a preset small pressure or flow disturbance into the pipeline network and collecting response data. Among them, based on the collected input-output data pairs The parameterized transfer function model is fitted using the least squares method. The identification process minimizes the following loss function. : ； In the formula, The parameter vector of the transfer function model to be identified; For at any time Actual measured pressure response value; For parameter-based The model at time Predicted pressure response value; This represents the total number of data points used for identification.

4. The method for online configuration and dynamic control of a low-pressure reactive power compensation system for a water conservancy pumping station according to claim 3, characterized in that, In step S2, when the operation involves the sequential start-up and shutdown of multiple water pumps, the planned safety impedance trajectory specifically includes: S201: Obtain the initial plan for the predetermined pump start / stop sequence and time interval; S202: Taking the hydraulic-electric coupling dynamic model as the object, with the goal of minimizing the rate of change of the system's equivalent impedance and keeping it within the impedance safety boundary throughout the entire process, optimize the precise start-up or shutdown time of each pump and the time interval between adjacent operations. S203: The optimized pump operation timing is mapped as a system equivalent impedance trajectory that evolves continuously on the impedance frequency-time plane, which is used as the safety impedance trajectory. The optimization solution process is described as the following constrained optimization problem: ； The constraints are: , ; ， ； In the formula, To optimize the objective function value; For optimization Secondary pump operation time vector. ; In frequency and time The equivalent impedance of the system under the following conditions; For frequency The following impedance safety zone; The start and end times of the transition process are considered for optimization. For the frequency range of interest; For the first Next and first The time interval between operations. ; and These are the physical upper and lower limits of the operation time interval.

5. The method for online configuration and dynamic control of a low-pressure reactive power compensation system for a water conservancy pumping station according to claim 4, characterized in that, In step S2, the preset impedance safety boundary is determined in the following way: Based on the aforementioned hydraulic-electric coupling dynamic model, the frequency characteristics of hydraulic impedance are compared and analyzed. The output impedance frequency characteristics of the low-voltage reactive power compensation system By calculating the impedance ratio To identify dangerous frequency regions close to -1; Around the identified danger frequency points Set a safety margin The impedance safety boundary is formed on the impedance frequency plane. Its definition is: ； In the formula, The bandwidth considered around the critical frequency point.

6. The method for online configuration and dynamic control of a low-pressure reactive power compensation system for a water conservancy pumping station according to claim 1, characterized in that, Step S3 specifically includes: S301: Discretize the safety impedance trajectory into multiple consecutive impedance state nodes on the time axis; S302: For each impedance state node, the reactive power output reference value of the static var generator in the low-voltage reactive power compensation system is obtained by inversely solving the hydraulic-electric coupling dynamic model to track the impedance state of that node. and the harmonic compensation command reference value for active filters. ; S303: Based on the reactive power output reference value and the harmonic compensation instruction reference value, and combined with the internal control strategy of the static var generator and the active filter, generate the corresponding controller parameter adjustment instruction; S304: Arrange the operation timing instructions of the water pump and valve, as well as the controller parameter adjustment instructions, in chronological order to form the coordinated control parameter sequence.

7. The method for online configuration and dynamic control of a low-pressure reactive power compensation system for a water conservancy pumping station according to claim 6, characterized in that, In step S303, generating the controller parameter adjustment instruction specifically includes: The operating mode of the active filter is dynamically configured according to the evolution stage of the safety impedance trajectory. During periods of drastic change in the system's equivalent impedance, the active filter is configured in a hybrid compensation mode that primarily suppresses impulsive harmonics while secondarily providing dynamic reactive power support. At this time, its output current references... And its current loop controller parameters are adjusted to , In the formula, The dynamic weighting coefficients for reactive power compensation components. ; , For a moment Proportional and integral parameters of the lower current control loop; , These are the rated parameters of the controller; Indicates the gain boost factor. ; During the phase when the system's equivalent impedance changes steadily, the active filter is configured to balance harmonic compensation and reactive power compensation.

8. The method for online configuration and dynamic control of a low-pressure reactive power compensation system for a water conservancy pumping station according to claim 1, characterized in that, In step S4, tracking the safety impedance trajectory specifically includes: S401: During operation, the actual system electrical quantities are monitored in real time through the monitoring, control and data acquisition system; S402: Based on real-time monitored electrical quantities, estimate the actual system equivalent impedance at the current moment online. ; S403: The equivalent impedance of the actual system... The reference impedance state at the corresponding moment in the safety impedance trajectory The comparison is performed, and if the deviation exceeds a preset threshold, an online correction mechanism is triggered. S404: The online correction mechanism fine-tunes the subsequent controller parameter adjustment instructions in the cooperative control parameter sequence in real time according to the deviation, so that the actual system equivalent impedance reconverges to the safe impedance trajectory.

9. The method for online configuration and dynamic control of a low-pressure reactive power compensation system for a water conservancy pumping station according to claim 8, characterized in that, The online correction mechanism is implemented using a model predictive control framework, specifically as follows: The hydraulic-electric coupling dynamic model is used as the prediction model. Based on the predicted equivalent impedance of the actual system within a finite future time window Compared with reference trajectory Minimizing the deviation is the optimization objective, and controller parameter adjustment commands are used. To optimize the variables, a rolling optimization solution is performed; Each control cycle solves the following optimization problem: ； The constraints are: ; ； ； ； In the formula, Indicates the current moment Regarding the future The predicted value of the system impedance at time; For the future The reference impedance trajectory value at time; Indicating a view on the future The predicted value of the control variable is controlled at all times; To control the increment; The control increment to be optimized; and This represents a positive definite matrix weighted by the changes in tracking error and control increment, respectively. To predict the length of the time domain; To control the length of the time domain, ; , and , Physical constraints for control variables and their increments; only the control increments from the first step are considered. Applied to the system.

10. An online configuration and dynamic control system, used to implement the online configuration and dynamic control method for a low-pressure reactive power compensation system of a water conservancy pumping station as described in any one of claims 1-9, characterized in that, include: The model management module is used for online construction and updating of dynamic models of hydraulic-electric coupling in pumping stations; The trajectory planning module plans the safety impedance trajectory based on the hydraulic-electric coupling dynamic model and preset operations; The cooperative sequence generation module generates the cooperative control parameter sequence based on the safety impedance trajectory; The closed-loop execution module is used to coordinate and control the water pump, valves, and the low-pressure reactive power compensation system to execute the coordinated control parameter sequence and achieve trajectory tracking. The model management module, trajectory planning module, collaborative sequence generation module, and closed-loop execution module are integrated into the upper-layer application server or a separate collaborative controller of the supervision, control, and data acquisition system.

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