A water pump control method and system based on TCU

Abstract

The invention discloses a water pump control method based on TCU, and specifically relates to the technical field of water pump operation control. Through a large amount of data sampling and analysis, a theoretical curve of each water pump is established, the working speed of the water pump and the opening of a water valve are dynamically adjusted through a UDS command, the changes of various working conditions are responded to in real time, the water pump output and the heat dissipation demand are effectively matched, the water valve opening is fixed and the feedback data is monitored while the water pump is running, so as to ensure the accuracy of the ID assignment of each water pump; the instantaneous frequency and energy of the water pump torque signal are analyzed through the Hilbert-Huang transform, the potential hidden dangers of the torque impact in the operation of the water pump are evaluated, the efficiency variation degree of the water pump in different time windows is comprehensively evaluated through the calculation of the sliding window entropy, and the service life of the water pump and related systems is effectively extended through the water pump selection strategy optimized based on the comprehensive analysis result.

Description

Technical Field

[0001] The present invention relates to the technical field of water pump operation control, and more specifically, to a water pump control method and system based on TCU. Background Art

[0002] In modern society, cars have become the main means of transportation. The automotive industry continues to develop and pursues higher safety, reliability, stability and environmental protection. To ensure the stable operation of the powertrain, actuators with motors are widely used, such as hydraulic actuators, shift actuators and brake boosters. In particular, the demand for engine heat dissipation is increasing, and efficient water pumps are required to circulate the coolant. Currently, two heat dissipation methods are used: single pump and multi-pump parallel. Among them, the multi-pump system is uniformly controlled by TCU to adapt to the heat dissipation needs of different working conditions, solving the size, cost and noise problems of the single pump system.

[0003] The existing water pump control system cannot accurately adjust the working status of each water pump to match the needs of different working conditions when multiple water pumps are running in parallel; traditional systems usually adopt a single adjustment strategy, which cannot effectively cope with various load and environmental changes, resulting in low energy efficiency and unstable cooling performance; this imprecise control may cause the water pump to overwork or underwork, increase mechanical wear, reduce equipment life, and increase energy consumption, thereby increasing operating costs and affecting the environmental performance and reliability of the entire vehicle.

[0004] In order to solve the above problems, a technical solution is now provided. Summary of the invention

[0005] In order to overcome the above-mentioned defects of the prior art, an embodiment of the present invention provides a water pump control method and system based on TCU to solve the problems raised in the above-mentioned background technology.

[0006] To achieve the above object, the present invention provides the following technical solutions:

[0007] A water pump control method based on TCU, comprising the following steps:

[0008] S1: Fit the relationship between the phase current of the water pump and the water valve opening through data sampling to establish the theoretical curve of each water pump;

[0009] S2: The controller sends a UDS command to control the water pump to run at a specified speed, gradually adjust the water valve opening, and record the water pump phase current and water valve opening; by comparing the actual curve with the theoretical curve, the water pump is assigned the most matching ID;

[0010] S3: Fix the water valve opening through the controller, run the water pump and monitor the feedback data to determine whether the ID assignment is accurate;

[0011] S4: When the ID assignment is accurate, the instantaneous frequency and energy of the water pump torque signal are analyzed by Hilbert-Huang transform to evaluate the potential hidden dangers of torque shock during water pump operation; the sliding window entropy is used to analyze the water pump efficiency time series to evaluate the degree of variation of the water pump efficiency within the time window;

[0012] S5: Optimize the water pump selection strategy based on a comprehensive analysis of the potential hazards of torque shock during water pump operation and the degree of efficiency variation of the water pump within the time window.

[0013] In a preferred embodiment, S1 specifically includes:

[0014] S101: equip each water pump with an independent current sensor and a water valve position sensor to uniformly collect data during the change of the water valve opening;

[0015] S102: under the guidance of the control system, gradually increase the water valve opening, and automatically record the current water valve opening and the corresponding water pump phase current every time it increases by a certain percentage;

[0016] S103: Use statistical software to perform regression analysis on the collected data of water pump phase current and water valve opening, and fit the theoretical performance curve of each water pump.

[0017] In a preferred embodiment, S2 specifically includes:

[0018] S201: Sending a UDS command through the controller to start and run the water pump at a specified speed;

[0019] S202: The control system gradually adjusts the water valve opening from 0% to 100%, and records the corresponding water pump phase current and water valve opening;

[0020] S203: comparing the collected actual water pump current curve with the previously fitted theoretical performance curve to evaluate the matching degree between the two;

[0021] S204: According to the matching result between the actual curve and the theoretical curve, the most matching ID is allocated to the water pump.

[0022] In a preferred embodiment, S3 specifically includes:

[0023] S301: Fix the water valve opening, eliminate the influence of dynamic adjustment, and verify the rationality of ID;

[0024] S302: running the water pump at a constant speed, collecting phase current and speed data in real time, and verifying whether the actual performance of the water pump matches the theoretical performance;

[0025] S303: Compare the feedback data with the theoretical curve, calculate the error through the Euclidean distance, and determine whether the ID allocation is accurate;

[0026] S304: Confirm the accuracy of the ID through data comparison results. If the match does not match, re-match and allocate the ID.

[0027] In a preferred embodiment, the instantaneous frequency and energy of the water pump torque signal are analyzed by Hilbert-Huang transform to evaluate the potential hidden dangers of torque shock during water pump operation, specifically:

[0028] Collect the starting torque signal of the water pump in real time and record it as the torque time series ,in Indicates time, A logo representing a water pump;

[0029] Perform empirical mode decomposition on the starting torque signal and decompose the complex signal into several intrinsic mode functions through an iterative method;

[0030] For each intrinsic mode function decomposed Perform Hilbert transform to calculate instantaneous frequency and instantaneous energy;

[0031] By Hilbert transform, calculate the instantaneous complex signal: ;in, is an instantaneous complex signal; is the intrinsic mode function The Hilbert transform of is the instantaneous amplitude; is the instantaneous phase; is an imaginary unit;

[0032] Through the instantaneous frequency and instantaneous amplitude, the torque impact energy distribution of the water pump on different time scales is obtained; the instantaneous energy Defined as: ;

[0033] By accumulating the instantaneous energy of each mode function, the total energy of the torque impact is obtained: ;in, is the total energy of the torque impulse;

[0034] According to the total energy of the torque impact, the evaluation value of the water pump startup hazard is calculated: ;in, It is the water pump startup hazard assessment value. is the length of the evaluation time window.

[0035] In a preferred embodiment, the specific decomposition process of decomposing a complex signal into several intrinsic mode functions is as follows:

[0036] right Calculate the local extreme values ​​and connect them to obtain the upper and lower envelopes;

[0037] The local mean of the signal is calculated through the envelope to obtain a preliminary decomposed signal;

[0038] Repeat the above steps until a stable intrinsic mode function is obtained. and residual .

[0039] In a preferred embodiment, the sliding window entropy is used to analyze the time series of water pump efficiency to evaluate the degree of variation of the water pump efficiency within the time window, specifically:

[0040] Collect input power and output power ;

[0041] Calculate the instantaneous efficiency. The calculation formula for instantaneous efficiency is: ;in, Shown at time point The instantaneous efficiency

[0042] The instantaneous efficiency data collected in real time is regarded as the efficiency time series, and is smoothed by time series analysis method to eliminate short-term fluctuations;

[0043] The entropy value of the efficiency time series is calculated by applying the sliding window entropy; the distribution of efficiency in each time window is estimated by the probability density function, and the formula is as follows: ;in, It means that in the time window The efficiency entropy within represents an interval index in a probability density distribution, represents the total number of divided efficiency value intervals, Indicates that the efficiency value is in the range The probability density within .

[0044] In a preferred embodiment, based on a comprehensive analysis of the potential hazards of torque shock during water pump operation and the degree of variation in the efficiency of the water pump within a time window, the water pump selection strategy is optimized, specifically:

[0045] Set the torque shock safety threshold corresponding to the water pump startup hazard assessment value ;

[0046] Set in time window The maximum allowable value of the efficiency entropy corresponding to the efficiency entropy ;

[0047] when and , then the water pump is determined to be available;

[0048] when or , then the water pump is determined to be unavailable.

[0049] On the other hand, the present invention provides a TCU-based water pump control system, including a data sampling module, an ID assignment module, an ID verification module, a torque analysis module, an efficiency evaluation module, and a selection optimization module;

[0050] Data sampling module: fits the relationship between the phase current of the water pump and the water valve opening through data sampling, and establishes the theoretical curve of each water pump;

[0051] ID assignment module: The controller sends UDS commands to control the water pump to run at a specified speed, gradually adjust the water valve opening, and record the water pump phase current and water valve opening; by comparing the actual curve with the theoretical curve, the water pump is assigned the most matching ID;

[0052] ID verification module: fix the water valve opening through the controller, run the water pump and monitor the feedback data to determine whether the ID assignment is accurate;

[0053] Torque analysis module: When the ID assignment is accurate, the instantaneous frequency and energy of the water pump torque signal are analyzed through Hilbert-Huang transform to evaluate the potential hidden dangers of torque shock during water pump operation;

[0054] Efficiency evaluation module: Apply sliding window entropy to analyze the time series of water pump efficiency and evaluate the degree of variation of water pump efficiency within the time window;

[0055] Selection Optimization Module: Optimizes the pump selection strategy based on a comprehensive analysis of the potential hazards of torque shock during pump operation and the degree of efficiency variation of the pump within the time window.

[0056] The technical effects and advantages of the TCU-based water pump control method and system of the present invention are as follows:

[0057] 1. Through a large amount of data sampling and analysis, a theoretical curve for each water pump is established, which enables the control system to compare the actual working conditions with the theoretical expectations, thereby achieving more precise control; secondly, the working speed of the water pump and the opening of the water valve are dynamically adjusted through UDS commands, which can respond to changes in various working conditions in real time and effectively match the water pump output with the heat dissipation requirements. In addition, the water valve opening is fixed and the feedback data is monitored while the water pump is running, ensuring the accuracy of the ID assignment of each water pump, further optimizing the selection and use efficiency of the water pump.

[0058] 2. By analyzing the instantaneous frequency and energy of the water pump torque signal through the Hilbert-Huang transform, it is not only possible to evaluate the potential hidden dangers of torque shock during water pump operation, but also to comprehensively evaluate the degree of efficiency variation of the water pump in different time windows through the calculation of sliding window entropy. This comprehensive analysis method not only improves the operating safety of the water pump, but also enhances the system's adaptability and stability to environmental changes, thereby significantly reducing energy waste caused by inefficiency or insufficient heat dissipation; ultimately, through the optimization of the water pump selection strategy based on the comprehensive analysis results, the service life of the water pump and related systems is effectively extended, and the maintenance cost is reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0059] Figure 1 A schematic diagram of a water pump control method based on TCU of the present invention;

[0060] Figure 2 It is a structural schematic diagram of a TCU-based water pump control system of the present invention. DETAILED DESCRIPTION

[0061] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0062] Example 1

[0063] Figure 1 The present invention provides a water pump control method based on TCU, which comprises the following steps:

[0064] S1: Fit the relationship between the water pump phase current and the water valve opening through data sampling to establish the theoretical curve of each water pump.

[0065] S2: The controller sends a UDS command to control the water pump to run at a specified speed, gradually adjust the water valve opening, and record the water pump phase current and water valve opening; by comparing the actual curve with the theoretical curve, the water pump is assigned the most matching ID.

[0066] S3: Fix the water valve opening through the controller, run the water pump and monitor the feedback data to determine whether the ID assignment is accurate.

[0067] S4: When the ID assignment is accurate, the instantaneous frequency and energy of the water pump torque signal are analyzed by Hilbert-Huang transform to evaluate the potential hidden dangers of torque shock during water pump operation; the sliding window entropy is used to analyze the water pump efficiency time series to evaluate the degree of efficiency variation of the water pump within the time window.

[0068] S5: Optimize the water pump selection strategy based on a comprehensive analysis of the potential hazards of torque shock during water pump operation and the degree of efficiency variation of the water pump within the time window.

[0069] Before establishing the theoretical curve for each water pump, it is important to know that the engine's cooling system includes multiple water pumps of the same model. Each water pump is configured with an independent ID control / feedback message through internal software, such as 0x0A / 0x11, 0x0B / 0x12, 0x0C / 0x13, etc., to facilitate effective allocation and management by the transmission control unit (TCU). During initialization, all water pumps are set to a no-ID state. At this time, the water pumps cannot respond to conventional control commands and can only perform basic control operations through UDS (Unified Diagnostic Service) commands. This design allows for flexible configuration and testing at the initial stage of system startup, ensuring that each water pump maintains a standardized and consistent response state before receiving a specific ID.

[0070] For example, the engine cooling system contains three main pipelines, each equipped with an electronically controlled water valve, and each water valve is equipped with a position sensor that can accurately control the opening of the water valve from 0% to 100%. The opening of the water valve directly affects the opening and closing state of the pipeline: when the water valve opening is 0%, all pipelines are closed and water is not allowed to flow through; when the water valve opening reaches 100%, all pipelines are fully open and water flow is maximized. The opening adjustment of each water valve is carried out by rotating clockwise. For example, when the water valve opening rotates from 0% to 10%, the first pipeline begins to gradually conduct until it is fully conducted at 30%, at which time the corresponding water pump phase current reaches the minimum; the second pipeline conducts between 40% and 60% of the water valve opening; and the third pipeline conducts between 70% and 90%. This setting enables the system to accurately adjust the water flow according to different water valve openings, thereby achieving fine control of water pump performance.

[0071] S1 specifically includes:

[0072] S101: Each water pump is equipped with an independent current sensor and water valve position sensor to ensure uniform data collection when the water valve opening changes from 0% to 100%:

[0073] Each water pump is equipped with a dedicated current sensor and position sensor to monitor the operation of the water pump at different openings in real time. The current sensor is used to measure the instantaneous phase current of the water pump, and the position sensor is used to accurately record the opening angle of the water valve to ensure uniform and accurate data collection within the entire opening range.

[0074] For example, the current sensor is selected based on a high-precision, low-latency electromagnetic induction sensor, with the measurement current range set to 0 to the maximum rated current value and a sampling frequency of 100 Hz, ensuring that the instantaneous current can be collected every 10 ms. The position sensor is a high-precision rotary encoder that can convert the opening of the water valve from 0% to 100% into a corresponding angle signal with a sampling accuracy of 0.1%.

[0075] The collected current value and water valve opening are expressed by the following function: ;in, It is The instantaneous phase current at each sampling point, Indicates The water valve opening angle corresponding to each sampling point (0° to 90°), is the number of the sampling point.

[0076] S102: Under the guidance of the control system, the water valve opening is gradually increased. Every time a certain percentage is increased, the current water valve opening and the corresponding water pump phase current are automatically recorded:

[0077] According to the pre-set strategy, the water valve opening is gradually increased, and the instantaneous current value of the current water pump and the water valve opening are collected at each opening. For example, the sampling point interval is 10ms to ensure the continuity and accuracy of the data. The water valve opening is gradually increased from 0% to 100%, which is divided into 1000 sampling points, that is, data is collected every 0.1% opening.

[0078] The controller uses the PID control algorithm to accurately control the change of the water valve opening. The output of the PID controller is used to adjust the water valve opening. The specific formula is: .

[0079] in:

[0080] is the controller at time The output of the time is used to adjust the water valve opening;

[0081] The error between the current set water valve opening and the actual opening;

[0082] is the proportional gain, a controller parameter used to adjust the current error Adjust the output of the system; its function is to quickly respond to the size of the error. The higher the proportional gain, the faster the system responds, but it may cause system instability.

[0083] It is the integral gain, which is used to eliminate long-standing errors. Integral control calculates the accumulated amount of error over time (integral), and affects the past error on the current control, thus ensuring the steady-state accuracy of the system.

[0084] It is the differential gain, which is used to predict the error change trend. By calculating the error change rate over time (differential), the differential control responds to system changes in advance, reduces overshoot, and improves system stability.

[0085] It is the instantaneous error, which represents the difference between the set value (target value) and the actual output value; the core working principle of the PID controller is to make adjustments based on this error.

[0086] At each sampling point, the pump current value recorded Water valve opening Forming data pairs , these data are used for subsequent curve fitting.

[0087] S103: Use statistical software to perform regression analysis on the collected data of water pump phase current and water valve opening, and fit the theoretical performance curve of each water pump:

[0088] The collected Substitute it into the nonlinear regression model and fit the performance curve of the water pump by the least square method. Find the function form that best describes the relationship between the phase current of the water pump and the water valve opening.

[0089] Assume that the theoretical curve of the fitting is in the form of: ;in, is the water valve opening; is the regression coefficient to be determined, and is solved by minimizing the sum of squared errors.

[0090] Regression coefficient Solve it by least square method, the specific process is: ;in, It is the optimization goal in mathematics, which means to minimize the function value under given conditions; is the total number of sampling points.

[0091] Through regression analysis, the specific theoretical performance curve of each pump is determined, and these curve data are stored for subsequent ID assignment.

[0092] S2 specifically includes:

[0093] S201: Send a UDS command through the controller to start and run the water pump at a specified speed to ensure that the water pump works according to the preset conditions:

[0094] The vehicle's transmission control unit (TCU) starts and runs the water pump via a unified diagnostic service (UDS) command. UDS is a standardized automotive diagnostic and control protocol that is widely used in vehicle electronic control unit (ECU) communications. At this point, the water pump aims to reach a preset speed for subsequent data collection and analysis.

[0095] First, the startup of the water pump is initialized and configured. The controller sends specific instructions to the water pump to ensure that it works at the set speed. For example, the water pump is set to run stably at a speed of 1000rpm. During this process, the TCU monitors the working status of the water pump in real time. If any deviation is detected, such as unstable speed or deviation from the target value, the controller will immediately send an adjustment signal to restore the normal operation of the water pump.

[0096] To ensure that the pump speed reaches the set value, the controller inside the system continuously adjusts the operating conditions of the pump through a feedback loop. When the pump speed is detected to deviate from the target value, the controller will adjust it based on the feedback error to make the pump speed match the set value again. This step ensures that the working conditions of the pump are consistent and controllable throughout the test process, avoiding the accuracy of subsequent data collection affected by speed fluctuations.

[0097] S202: The control system gradually adjusts the water valve opening from 0% to 100%, and records the corresponding water pump phase current and water valve opening:

[0098] When the water pump runs at a stable specified speed, the control system begins to gradually adjust the water valve opening, and the water valve opening range gradually increases from 0% (fully closed) to 100% (fully open). After each adjustment, the system automatically collects the corresponding water pump phase current data and water valve opening, and records these data.

[0099] The opening of the water valve increases by a fixed step size each time, for example, by 5% each time, so that the entire opening range is divided into multiple uniform sampling points. For example, when the water valve opening is 0%, all pipelines are closed, and the phase current of the water pump is the lowest at this time; as the water valve is gradually opened, the phase current of the water pump will gradually increase until the water valve is fully opened and reaches the maximum current.

[0100] S203: Compare the collected actual water pump current curve with the previously fitted theoretical performance curve to evaluate the matching degree between the two:

[0101] The actual phase current curve of the water pump will be compared with the theoretical performance curve obtained by data fitting. To this end, the Euclidean distance is used to calculate the difference between the two curves to evaluate the degree of match between the actual curve and the theoretical curve.

[0102] The Euclidean distance is obtained by calculating the difference between the actual current and the theoretical current at each sampling point, squaring the differences and summing them up, and finally taking the square root.

[0103] The larger the Euclidean distance is, the more significant the difference between the actual performance of the pump and the theoretical model is.

[0104] The Euclidean distance is compared with a preset threshold. When the Euclidean distance is less than the preset threshold, it is determined that the two are matched successfully and the next step is allowed.

[0105] The preset threshold of the Euclidean distance is set by professionals in the field based on experiments and actual conditions.

[0106] S204: According to the matching result between the actual curve and the theoretical curve, the most matching ID is assigned to the water pump to facilitate subsequent independent control:

[0107] When the two are determined to match successfully, the controller will assign the most suitable ID to the water pump. Each water pump ID is its unique identifier, which is used to achieve independent control in the multi-pump system later.

[0108] The ID is transmitted to the water pump control unit through the UDS command so that the TCU can identify and control the water pump individually through the ID in subsequent operations. The ID of each water pump will be stored in the TCU database to ensure that each water pump can be independently scheduled and controlled according to different cooling requirements in subsequent operations.

[0109] S3 specifically includes:

[0110] S301: Fixed water valve opening, eliminating the impact of dynamic adjustment, focusing on the performance of the water pump under stable working conditions to verify the rationality of ID:

[0111] After step S2 is completed, the system assigns the best matching ID to each water pump. In order to verify the accuracy of the ID, the system will control the water valve opening to be fixed at a specific position, such as 50%. At this time, the water pump should operate under fixed water flow conditions, and the water valve opening will no longer change.

[0112] By fixing the water valve opening, the impact of dynamic adjustment of the water valve on the performance of the water pump can be eliminated, so that only the performance of the water pump under stable working conditions can be focused on.

[0113] The water valve opening is set by the system, for example 50%, which means that when the water pump is working, the water flow through the water pump corresponds to the 50% water valve opening. At this time, the current of the water pump should be stable within a specific range.

[0114] S302: Run the water pump at a constant speed, collect phase current and speed data in real time, and verify whether the actual performance of the water pump matches the theoretical performance:

[0115] The system sends a UDS command to make the pump run at a fixed speed and continuously monitors the feedback data of the pump. The feedback data includes the phase current, speed and operating status of the pump. At this point, the working status of the pump should be consistent with the performance expected by the previous theoretical curve.

[0116] The actual phase current of the water pump is collected in real time through the current sensor, and the current value corresponding to the fixed water valve opening is recorded. Monitor whether the water pump remains within the specified speed range to ensure the performance of the water pump at a constant speed.

[0117] S303: Compare the feedback data with the theoretical curve, calculate the error through the Euclidean distance, and determine whether the ID allocation is accurate:

[0118] The collected feedback data is compared with the theoretical performance curve to verify whether the operating state of the water pump under the fixed water valve opening is consistent with the theoretical state corresponding to the assigned ID. Similar to the real-time data comparison in step S2, the Euclidean distance between the two is calculated to determine whether the assigned ID is accurate.

[0119] If the Euclidean distance is within the set tolerance range, it is determined that the actual performance of the pump matches the theoretical model, indicating that the assigned ID is accurate.

[0120] S304: Confirm the accuracy of the ID through data comparison results. If the match does not match, re-match and assign the ID:

[0121] By comparing the feedback data, the system finally determines whether the ID assignment is accurate. If the error between the feedback data and the theoretical model is within the allowable range, the ID assignment of the pump is confirmed to be correct, and the pump can be independently controlled according to the ID. If the error exceeds the preset threshold, the system will re-match and assign the ID until a suitable ID is found.

[0122] ID verification passed: The system records the pump ID and its corresponding operating data as the basis for subsequent independent control. The accuracy of the ID assignment is verified by comparing the results.

[0123] ID verification failed: If the verification fails, the system triggers the reallocation process and adjusts the ID or repeats the steps of S2 to find the most suitable ID.

[0124] The instantaneous frequency and energy of the water pump torque signal are analyzed by Hilbert-Huang transform to evaluate the potential hidden dangers of torque shock during water pump operation. Specifically:

[0125] The Hilbert-Huang transform is suitable for analyzing nonlinear and non-stationary signals, especially the transient torque shock when the pump starts, and can perform in-depth analysis by decomposing the complex patterns in the signal.

[0126] When the water pump starts, the starting torque signal of the water pump is collected in real time through a high-precision torque sensor and recorded as a torque time series. ,in Indicates time; It represents the identification of the water pump, which is the symbol used to distinguish different water pumps.

[0127] The starting torque signal indicates the torque change of the water pump at the moment of starting. The signal data has obvious nonlinear characteristics, especially under high load or high temperature conditions.

[0128] In order to analyze the different dynamic components in the starting torque signal, the empirical mode decomposition is performed on the starting torque signal. Through an iterative method, the complex signal is decomposed into several intrinsic mode functions (IMFs), each of which represents the signal component at different time scales.

[0129] The specific decomposition process is as follows:

[0130] right Calculate the local extreme values ​​and connect them to obtain the upper and lower envelopes.

[0131] The local mean of the signal is calculated through the envelope to obtain the preliminary decomposition signal.

[0132] Repeat the above steps until a stable intrinsic mode function is obtained. and residual .

[0133] It can be expressed as follows: .

[0134] in, Indicates The intrinsic mode functions, Represents the number of the decomposed intrinsic mode function.

[0135] Indicates the total number of mode functions decomposed.

[0136] is the residual, which represents the part of the signal that has not been decomposed.

[0137] The purpose of empirical mode decomposition is to decompose the complex dynamic characteristics of the original torque signal into different frequency components so that the subsequent analysis can deal with the impact phenomena at different time scales separately.

[0138] For each intrinsic mode function decomposed Hilbert transform is performed to calculate the instantaneous frequency and instantaneous energy. By analyzing these instantaneous characteristics, the impact intensity when the water pump is started can be evaluated.

[0139] By Hilbert transform, calculate the instantaneous complex signal: ;in, is an instantaneous complex signal; is the intrinsic mode function The Hilbert transform of is the instantaneous amplitude; is the instantaneous phase; It is the imaginary unit and is often used to represent the imaginary part in complex mathematics.

[0140] The instantaneous frequency is calculated as: ;in, is the instantaneous frequency.

[0141] Through the instantaneous frequency and instantaneous amplitude, the torque impact energy distribution of the water pump on different time scales can be obtained.

[0142] Instantaneous energy Defined as: .

[0143] By accumulating the instantaneous energy of each mode function, the total energy of the torque impact can be obtained: .

[0144] In order to quantitatively evaluate the degree of hidden dangers when the water pump is started, the hidden danger assessment value of the water pump startup is calculated according to the total energy of the torque impact: ;in, It is the water pump startup hazard assessment value, indicating the average level of impact energy during the water pump startup process; To evaluate the length of the time window, a few seconds after the pump is started are usually selected for evaluation.

[0145] A higher water pump startup hazard assessment value means a greater impact at startup and a greater potential hazard of torque shock during water pump operation, which may cause premature aging or wear of the water pump and related mechanical structures, thereby having a negative impact on system reliability.

[0146] The torque impact at water pump startup is analyzed in detail through Hilbert-Huang transform, different frequency components are decomposed and the instantaneous frequency and instantaneous energy are calculated. Finally, the water pump startup hazard assessment value is calculated through the total energy to quantify the potential risks in the water pump startup process. This can not only accurately capture the nonlinear starting characteristics of the water pump, but also provide an effective monitoring and evaluation method for the safety of system operation.

[0147] The sliding window entropy is used to analyze the pump efficiency time series and evaluate the efficiency variation of the pump within the time window. Specifically:

[0148] Collect input power : Indicates the time A measure of the energy consumed by a pump, usually expressed in kilowatts (kW). Input power is the total energy the pump draws from the grid or other energy system.

[0149] Collect output power :Indicates that the water pump is at the same time A measure of the amount of energy converted into fluid power. This reflects the efficiency with which the pump is actually doing work and is usually also expressed in kilowatts (kW).

[0150] A combination of electrical sensors and flow meters are used to accurately measure electrical input and fluid output. These sensors require regular calibration to ensure data accuracy.

[0151] Calculate the instantaneous efficiency. The calculation formula for instantaneous efficiency is: ;in, Shown at time point The instantaneous efficiency is a direct indicator of the energy conversion efficiency of the water pump. The closer the instantaneous efficiency value is to 1, the higher the energy conversion efficiency.

[0152] The instantaneous efficiency data collected in real time is regarded as an efficiency time series, and is smoothed by time series analysis methods to eliminate short-term fluctuations and highlight the overall trend of efficiency changes. For example, the moving average or exponential smoothing method is used to process the data.

[0153] Through the smoothed time series, the system can more clearly capture the changing trend of efficiency during long-term operation and avoid the impact of short-term fluctuations on subsequent entropy calculations.

[0154] In order to quantify the efficiency fluctuation of the water pump in different time windows, the sliding window entropy is applied to calculate the entropy value of the efficiency time series.

[0155] The calculation of entropy is based on information entropy theory, and the distribution of efficiency in each time window is estimated through the probability density function (PDF). The formula is as follows: ;in, It means that in the time window The efficiency entropy within the time window measures the uncertainty of the pump efficiency fluctuation within the time window; Represents an interval index in the probability density distribution, which is the index of the discretized efficiency value and is used to divide different intervals in the probability distribution; Represents the total number of efficiency value intervals divided. The probability density distribution of the entire efficiency data is divided into intervals; Indicates that the efficiency value is in the range The probability density within the interval indicates the probability of efficiency occurring within the interval, which is the probability of the entire time window The probability value of appearing within a certain efficiency range.

[0156] In the time window The higher the efficiency entropy within the time window, the more unstable the change of the pump efficiency within the time window, and the greater the variation of the pump efficiency; The lower the efficiency entropy is, the more stable the pump efficiency is and the smaller the variation of the pump efficiency is.

[0157] Based on the comprehensive analysis of the potential hidden dangers of torque shock during water pump operation and the degree of variation in the efficiency of the water pump within the time window, the water pump selection strategy is optimized, specifically:

[0158] According to the allowable range of system design, set the torque shock safety threshold corresponding to the water pump startup hazard assessment value .if , it means that the water pump may have major hidden dangers and it is not recommended to continue using it.

[0159] Set in time window The maximum allowable value of the efficiency entropy corresponding to the efficiency entropy .if , it means that the efficiency of the pump fluctuates greatly and is not suitable for operation under the current working conditions.

[0160] The pump startup hazard assessment value and the time window The efficiency entropy in the pump is compared with the respective thresholds, and the two factors are combined to optimize the pump selection:

[0161] when and , the water pump is judged to be available, indicating that the water pump is in good operating condition and suitable for continued use.

[0162] when or , then the water pump is judged to be unavailable, the water pump may have hidden dangers or large efficiency fluctuations, and other water pumps should be selected first.

[0163] Based on the above comparison results, the water pump that meets the torque impact and efficiency stability requirements is automatically selected, the selection strategy is updated and the operating parameters are adjusted.

[0164] For the water pumps determined to be available, they are preferentially selected as the operating water pumps in the current working condition.

[0165] For pumps that are determined to be unavailable, they are listed as equipment to be repaired or as spare equipment, and the operating strategies of other pumps are adjusted according to the operating conditions.

[0166] By combining the torque shock hazard when the pump is started with the degree of efficiency fluctuation during its operation and comprehensively analyzing these two factors, the pump selection strategy can be optimized to ensure that the system always selects pumps with small hazards and stable efficiency. This method effectively avoids the continued operation of pumps with large hazards or unstable efficiency, thereby reducing the possibility of failure and extending the service life of the equipment. The system can automatically determine whether the pump is suitable for the current working conditions, reduce manual intervention, improve overall operating efficiency and reliability, and ensure efficient operation and maintenance of the system.

[0167] Example 2

[0168] The difference between Example 2 of the present invention and Example 1 is that this example introduces a water pump control system based on TCU.

[0169] Figure 2 A structural schematic diagram of a TCU-based water pump control system of the present invention is given, a TCU-based water pump control system includes a data sampling module, an ID assignment module, an ID verification module, a torque analysis module, an efficiency evaluation module and a selection optimization module.

[0170] Data sampling module: fits the relationship between the water pump phase current and the water valve opening through data sampling, and establishes the theoretical curve of each water pump.

[0171] ID assignment module: The controller sends UDS commands to control the water pump to run at a specified speed, gradually adjust the water valve opening, and record the water pump phase current and water valve opening; by comparing the actual curve with the theoretical curve, the water pump is assigned the most matching ID.

[0172] ID Verification Module: Fix the water valve opening through the controller, run the water pump and monitor the feedback data to determine whether the ID assignment is accurate.

[0173] Torque analysis module: When the ID assignment is accurate, the instantaneous frequency and energy of the water pump torque signal are analyzed through the Hilbert-Huang transform to evaluate the potential hidden dangers of torque shock during water pump operation.

[0174] Efficiency evaluation module: Apply sliding window entropy to analyze the pump efficiency time series and evaluate the efficiency variation of the pump within the time window.

[0175] Selection Optimization Module: Optimize the pump selection strategy based on a comprehensive analysis of the potential hazards of torque shock during pump operation and the degree of efficiency variation of the pump within the time window.

[0176] The above formulas are all dimensionless and numerical calculations. The formula is a formula for the most recent real situation obtained by collecting a large amount of data and performing software simulation. The preset parameters and thresholds in the formula are set by technicians in this field according to actual conditions.

[0177] The above embodiments may be implemented in whole or in part by software, hardware, firmware or any other combination thereof. When implemented by software, the above embodiments may be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions or computer programs. When the computer instructions or computer programs are loaded or executed on a computer, the process or function described in the embodiment of the present application is generated in whole or in part. The computer may be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions may be stored in a computer-readable storage medium, or may be transmitted from one computer-readable storage medium to another computer-readable storage medium. For example, the computer instructions may be transmitted from one website, computer, server or data center to another website, computer, server or data center by wired (e.g., infrared, wireless, microwave, etc.) means. The computer-readable storage medium may be any available medium that a computer can access or a data storage device such as a server or data center that contains one or more available media sets. The available medium may be a magnetic medium (e.g., a floppy disk, a hard disk, a tape), an optical medium (e.g., a DVD), or a semiconductor medium. The semiconductor medium may be a solid-state hard disk.

[0178] Those of ordinary skill in the art will appreciate that the modules and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of this application.

[0179] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working processes of the systems, devices and modules described above can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0180] In the several embodiments provided in the present application, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. For example, the device embodiments described above are only schematic. For example, the division of the modules is only a logical function division. There may be other division methods in actual implementation, such as multiple modules or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or modules, which can be electrical, mechanical or other forms.

[0181] The modules described as separate components may or may not be physically separated, and the components shown as modules may or may not be physical modules, and may be located in one place or distributed on multiple network modules. Some or all of the modules may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0182] In addition, each functional module in each embodiment of the present application may be integrated into one processing module, or each module may exist physically separately, or two or more modules may be integrated into one module.

[0183] If the functions are implemented in the form of software function modules and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application can be essentially or partly embodied in the form of a software product that contributes to the prior art. The computer software product is stored in a storage medium, including several instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the methods described in the various embodiments of the present application. The aforementioned storage media include: U disk, mobile hard disk, read-only memory (ROM), random access memory (RAM), disk or optical disk, and other media that can store program codes.

[0184] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art who is familiar with the present technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

[0185] Finally: The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A water pump control method based on TCU, characterized in that: The steps include: S1: Fit the relationship between the phase current of the water pump and the water valve opening through data sampling to establish the theoretical curve of each water pump; S2: The controller sends a UDS command to control the water pump to run at a specified speed, gradually adjust the water valve opening, and record the water pump phase current and water valve opening; by comparing the actual curve with the theoretical curve, the water pump is assigned the most matching ID; S3: Fix the water valve opening through the controller, run the water pump and monitor the feedback data to determine whether the ID assignment is accurate; S4: When the ID assignment is accurate, the instantaneous frequency and energy of the water pump torque signal are analyzed by Hilbert-Huang transform to evaluate the potential hidden dangers of torque shock during water pump operation; the sliding window entropy is used to analyze the water pump efficiency time series to evaluate the degree of variation of the water pump efficiency within the time window; S5: Optimize the pump selection strategy based on the comprehensive analysis of the potential hidden dangers of torque shock during pump operation and the degree of efficiency variation of the pump within the time window; TCU stands for Transmission Control Unit; The water valve is an electronically controlled valve in the engine cooling system. The opening is adjusted by a position sensor. The opening affects the relationship between the phase current of the corresponding water pump and the pipeline flow rate. UDS stands for Unified Diagnostic Service, which is a standardized automotive diagnostic and control protocol; Based on the comprehensive analysis of the potential hidden dangers of torque shock during water pump operation and the degree of variation in the efficiency of the water pump within the time window, the water pump selection strategy is optimized, specifically: Set the torque shock safety threshold corresponding to the water pump startup hazard assessment value ; Set in time window The maximum allowable value of the efficiency entropy corresponding to the efficiency entropy ; when and , then the water pump is determined to be available; when , then the water pump is determined to be unavailable.

2. The water pump control method based on TCU according to claim 1, characterized in that S1 specifically comprises: S101: equip each water pump with an independent current sensor and a water valve position sensor to uniformly collect data during the change of the water valve opening; S102: under the guidance of the control system, gradually increase the water valve opening, and automatically record the current water valve opening and the corresponding water pump phase current every time it increases by a certain percentage; S103: Use statistical software to perform regression analysis on the collected data of water pump phase current and water valve opening, and fit the theoretical performance curve of each water pump.

3. A water pump control method based on TCU according to claim 2, characterized in that: S2 specifically includes: S201: Sending a UDS command through the controller to start and run the water pump at a specified speed; S202: The control system gradually adjusts the water valve opening from 0% to 100%, and records the corresponding water pump phase current and water valve opening; S203: comparing the collected actual water pump current curve with the previously fitted theoretical performance curve to evaluate the matching degree between the two; S204: According to the matching result between the actual curve and the theoretical curve, the most matching ID is allocated to the water pump.

4. A TCU-based water pump control method according to claim 3, characterized in that: S3 specifically includes: S301: Fix the water valve opening, eliminate the influence of dynamic adjustment, and verify the rationality of ID; S302: running the water pump at a constant speed, collecting phase current and speed data in real time, and verifying whether the actual performance of the water pump matches the theoretical performance; S303: Compare the feedback data with the theoretical curve, calculate the error through the Euclidean distance, and determine whether the ID allocation is accurate; S304: Confirm the accuracy of the ID through data comparison results. If the match does not match, re-match and allocate the ID.

5. A TCU-based water pump control method according to claim 4, characterized in that: The instantaneous frequency and energy of the water pump torque signal are analyzed by Hilbert-Huang transform to evaluate the potential hidden dangers of torque shock during water pump operation. Specifically: Collect the starting torque signal of the water pump in real time and record it as the torque time series , which indicates time, A logo representing a water pump; Perform empirical mode decomposition on the starting torque signal and decompose the complex signal into several intrinsic mode functions through an iterative method; For each intrinsic mode function decomposed Perform Hilbert transform to calculate instantaneous frequency and instantaneous energy; By Hilbert transform, calculate the instantaneous complex signal: ;in, is an instantaneous complex signal; is the intrinsic mode function The Hilbert transform of is the instantaneous amplitude; is the instantaneous phase; is an imaginary unit; Through the instantaneous frequency and instantaneous amplitude, the torque impact energy distribution of the water pump on different time scales is obtained; the instantaneous energy Defined as: ; By accumulating the instantaneous energy of each mode function, the total energy of the torque impact is obtained: ;in, is the total energy of the torque impulse; According to the total energy of the torque impact, the evaluation value of the water pump startup hazard is calculated: ;in, It is the water pump startup hazard assessment value. is the length of the evaluation time window.

6. A water pump control method based on TCU according to claim 5, characterized in that: The specific decomposition process of decomposing a complex signal into several intrinsic mode functions is as follows: right Calculate the local extreme values ​​and connect them to obtain the upper and lower envelopes; The local mean of the signal is calculated through the envelope to obtain a preliminary decomposed signal; Repeat the above steps until a stable intrinsic mode function is obtained. and residual .

7. A water pump control method based on TCU according to claim 6, characterized in that: The sliding window entropy is used to analyze the pump efficiency time series and evaluate the efficiency variation of the pump within the time window. Specifically: Collect input power and output power ; Calculate the instantaneous efficiency. The calculation formula for instantaneous efficiency is: ;in, Shown at time point The instantaneous efficiency The instantaneous efficiency data collected in real time is regarded as the efficiency time series, and is smoothed by time series analysis method to eliminate short-term fluctuations; The entropy value of the efficiency time series is calculated by applying the sliding window entropy; the distribution of efficiency in each time window is estimated by the probability density function, and the formula is as follows: ;in, It means that in the time window The efficiency entropy within represents an interval index in a probability density distribution, shows the total number of efficiency value intervals divided, Indicates that the efficiency value is in the range The probability density within .

8. A water pump control system based on TCU, used to implement a water pump control method based on TCU according to any one of claims 1 to 7, characterized in that: It includes data sampling module, ID assignment module, ID verification module, torque analysis module, efficiency evaluation module and selection optimization module; Data sampling module: fits the relationship between the phase current of the water pump and the water valve opening through data sampling, and establishes the theoretical curve of each water pump; ID assignment module: The controller sends UDS commands to control the water pump to run at a specified speed, gradually adjust the water valve opening, and record the water pump phase current and water valve opening; By comparing the actual curve with the theoretical curve, the pump is assigned the most matching ID; ID verification module: fix the water valve opening through the controller, run the water pump and monitor the feedback data to determine whether the ID assignment is accurate; Torque analysis module: When the ID assignment is accurate, the instantaneous frequency and energy of the water pump torque signal are analyzed through Hilbert-Huang transform to evaluate the potential hidden dangers of torque shock during water pump operation; Efficiency evaluation module: Apply sliding window entropy to analyze the time series of water pump efficiency and evaluate the degree of variation of water pump efficiency within the time window; Selection Optimization Module: Optimizes the pump selection strategy based on a comprehensive analysis of the potential hazards of torque shock during pump operation and the degree of efficiency variation of the pump within the time window.

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