Adaptive control method and system for variable frequency water pump

Abstract

The invention relates to the technical field of variable-frequency water pump control, in particular to a variable-frequency water pump self-adaptive control method and system.The method comprises the steps that motor parameters of a variable-frequency water pump are collected, and whether the motor parameters meet preset starting threshold conditions at the same time or not is judged; under the condition that the starting condition of the motor is met, sensing information of all sensors on the variable frequency water pump is collected; the collected motor parameters and sensing information are preprocessed, filtered and denoised, and key information is extracted; calculating a motor state analysis result based on the processed motor parameters and sensing information, and performing fault diagnosis and prediction to obtain a motor state analysis result; and according to the motor state analysis result, the output voltage, frequency and phase of the frequency converter are dynamically adjusted to optimize the operation efficiency and stability of the water pump. The operation state of the water pump motor is monitored and analyzed in real time, accurate calculation and evaluation are combined, the output parameters of the frequency converter are dynamically adjusted, and efficient and stable operation of the water pump is achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of variable frequency water pump control, and in particular to an adaptive control method and system for a variable frequency water pump. Background Art

[0002] Traditional water pump systems usually adopt a fixed speed operation mode, which cannot flexibly adjust the flow and pressure according to actual needs, resulting in energy waste and equipment wear. With the development of frequency conversion technology, variable frequency water pumps have become an important means to improve the energy efficiency of water pump systems because they can automatically adjust the speed and output power according to the actual load. However, most of the existing variable frequency water pump control systems are based on preset control strategies, lack the ability to accurately perceive the real-time status of the motor and dynamically adjust it, and are difficult to adapt to complex and changing working conditions. Summary of the invention

[0003] One purpose of the present invention is to propose an adaptive control method for a variable frequency water pump, which dynamically adjusts the output parameters of the frequency converter by real-time monitoring and analysis of the operating status of the water pump motor, combined with precise calculation and evaluation, to achieve efficient and stable operation of the water pump and extend the service life of the equipment.

[0004] Another object of the present invention is to propose an adaptive control system for a variable frequency water pump, introduce the detailed calculation content and analysis method in the adaptive control method for a variable frequency water pump as described above, and improve the adaptability and control accuracy of the control system.

[0005] To achieve this object, the present invention adopts the following technical solutions:

[0006] An adaptive control method for a variable frequency water pump comprises the following steps:

[0007] Step S1: collecting motor parameters of the variable frequency water pump, including line resistance, line inductance and back electromotive force;

[0008] Step S2: When the motor startup conditions are met, sensor information of each sensor on the variable frequency water pump is collected, including temperature information, vibration information and noise information;

[0009] Step S3: preprocessing, filtering and denoising the collected motor parameters and sensor information to extract key information;

[0010] Step S4: Based on the processed motor parameters and sensor information, calculate the load rate, evaluate the efficiency, monitor the thermal state, analyze the electrical characteristics and vibration and noise conditions, and perform fault diagnosis and prediction to obtain the motor state analysis results;

[0011] Step S5: According to the motor status analysis result, dynamically adjust the output voltage, frequency and phase of the inverter to optimize the operating efficiency and stability of the water pump.

[0012] Preferably, in step S1, it also includes judging whether the line resistance, line inductance and back electromotive force reach a first threshold, a second threshold and a third threshold to determine whether the motor meets the starting conditions.

[0013] Preferably, the calculation of the load rate in step S4 includes measuring the actual current I of the motor 实际 And with the rated current I 额定 Compare, calculate the load factor λ and quantify the load degree;

[0014] Where λ = I 实际 / I 额定 ;

[0015] The load level is set to:

[0016] When 0≤λ<0.5, the motor is considered to be in a light load state;

[0017] When 0.5≤λ<0.8, the motor is considered to be in a medium load state;

[0018] When 0.8≤λ<1.0, the motor is considered to be in a heavy load state;

[0019] When λ≥1.0, the motor is considered to be in an overload state.

[0020] Preferably, the efficiency evaluation in step S4 is performed by calculating the input power Pin and the output power Pout of the motor, and by comparing the two to obtain the electrical efficiency η1= and the electrical efficiency loss Lossη, and quantify the degree of loss;

[0021] Among them, input power Pin = V × I, I is the motor current, V is the voltage;

[0022] Output power Pout = ρ × g × H × Q / 3600, ρ is the fluid density, g is the acceleration of gravity, Q is the flow rate, and H is the head;

[0023] Electrical efficiency η1 = Pin / Pout × 100%;

[0024] The electrical efficiency loss Lossη is calculated by one or a combination of the following calculations:

[0025] Lossη=(η2-η1) / η2×100%, η2 is the rated electrical efficiency;

[0026] Lossη=(η3-η1) / η3×100%, η3 is the historical average electrical efficiency;

[0027] The loss level is set as:

[0028] When Lossη≤5%, it is considered that the efficiency loss of the motor is in a small state;

[0029] When Lossη>5%, it is considered that the efficiency loss of the motor is in a large state.

[0030] Preferably, monitoring the thermal state in step S4 includes using a temperature sensor and a thermal model of the motor to evaluate whether the operating temperature of the motor is close to or exceeds a maximum allowable operating temperature.

[0031] Preferably, analyzing the electrical characteristics in step S4 includes evaluating the winding state of the motor using changes in line resistance and line inductance, and evaluating the magnetic flux and magnetic field strength of the motor using changes in back electromotive force.

[0032] Preferably, the vibration and noise conditions in step S4 include monitoring the vibration and noise conditions of the motor using vibration and noise sensors to identify potential mechanical failures.

[0033] An adaptive control system for a variable frequency water pump, using the adaptive control method for a variable frequency water pump as described above, comprises:

[0034] The first data acquisition module is used to collect motor parameters of the variable frequency water pump, including line resistance, line inductance and back electromotive force;

[0035] A data judgment module is used to judge whether the motor parameters meet the preset starting threshold conditions at the same time, so as to determine whether the motor meets the starting conditions;

[0036] The second data acquisition module is used to collect sensor information of each sensor on the variable frequency water pump, including temperature information, vibration information and noise information, when the motor startup conditions are met;

[0037] The data processing module is used to pre-process, filter and denoise the collected motor parameters and sensor information to extract key information;

[0038] The data calculation module is used to calculate the load rate, evaluate the efficiency, monitor the thermal status, analyze the electrical characteristics and vibration and noise conditions, and perform fault diagnosis and prediction based on the processed motor parameters and sensor information to obtain the motor status analysis results;

[0039] The control execution module is used to dynamically adjust the output voltage, frequency and phase of the variable frequency water pump according to the motor status analysis results to optimize the operating efficiency and stability of the water pump.

[0040] One of the above technical solutions has the following beneficial effects:

[0041] In summary, the adaptive control method of the variable frequency water pump has the following beneficial effects:

[0042] (1) Improve operating efficiency: By accurately controlling the output parameters of the inverter, the water pump can operate under the optimal working conditions, reducing unnecessary energy loss and improving the overall operating efficiency of the system.

[0043] (2) Enhanced stability: Real-time monitoring and analysis of the operating status of the water pump can promptly detect and deal with potential problems, effectively preventing the occurrence of failures and enhancing the stability and reliability of the system.

[0044] (3) Extending service life: By optimizing operating parameters and fault prediction, equipment damage caused by adverse factors such as overload and overheating can be avoided, thereby extending the service life of the water pump.

[0045] (4) Energy saving and emission reduction: Due to the improved operating efficiency and reduced downtime, this method helps to reduce energy consumption and maintenance costs, which is in line with the concept of green and sustainable development.

[0046] (5) Intelligent management: By integrating advanced sensor technology and data analysis algorithms, intelligent management of water pump operation is achieved, reducing the need for manual intervention and improving management efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] Figure 1 It is a flow chart of an adaptive control method of a variable frequency water pump of the present invention. DETAILED DESCRIPTION

[0048] The technical solution of the present invention is further described below with reference to the accompanying drawings and through specific implementation methods.

[0049] In the description of the present invention, it is to be understood that the terms “center”, “longitudinal”, “lateral”, “length”, “width”, “thickness”, “up”, “down”, “left”, “right”, “vertical”, “horizontal”, “top”, “bottom”, “inside”, “outside”, “axial”, “radial”, “circumferential”, etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0050] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "plurality" means two or more.

[0051] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0052] like Figure 1 As shown, an adaptive control method for a variable frequency water pump comprises the following steps:

[0053] Step S1: collecting motor parameters of the variable frequency water pump, including line resistance, line inductance and back electromotive force;

[0054] Step S2: When the motor startup conditions are met, sensor information of each sensor on the variable frequency water pump is collected, including temperature information, vibration information and noise information;

[0055] Step S3: preprocessing, filtering and denoising the collected motor parameters and sensor information to extract key information;

[0056] Step S4: Based on the processed motor parameters and sensor information, calculate the load rate, evaluate the efficiency, monitor the thermal state, analyze the electrical characteristics and vibration and noise conditions, and perform fault diagnosis and prediction to obtain the motor state analysis results;

[0057] Step S5: According to the motor status analysis result, dynamically adjust the output voltage, frequency and phase of the inverter to optimize the operating efficiency and stability of the water pump.

[0058] The adaptive control method of this variable frequency water pump aims to achieve accurate adjustment of its working parameters by real-time monitoring and analysis of the operating status of the water pump, thereby achieving the purpose of optimizing operating efficiency and stability. Its detailed working principle is as follows:

[0059] Data collection (steps S1 and S2):

[0060] Motor parameter acquisition: Through specialized measuring equipment or sensors integrated in the motor controller, key electrical parameters such as line resistance, line inductance, and back electromotive force of the motor are collected in real time. These parameters directly reflect the electromagnetic state and performance characteristics of the motor.

[0061] Sensor information collection: Temperature sensors, vibration sensors and noise sensors installed at key parts of the water pump are used to collect temperature, vibration and noise information during the operation of the water pump. This information is crucial for evaluating the mechanical status and health of the water pump.

[0062] Data preprocessing (step S3):

[0063] The collected raw data is preprocessed, including filtering to remove noise interference and denoising to improve data quality. Subsequently, data analysis technology is used to extract information that has a key impact on subsequent analysis.

[0064] Status analysis and evaluation (step S4):

[0065] Based on the preprocessed data, the algorithm model is used to calculate the load rate of the water pump and evaluate its operating efficiency. At the same time, the thermal state of the water pump is monitored to prevent damage caused by overheating.

[0066] Analyze electrical characteristics, such as motor current fluctuations, and the frequency spectrum characteristics of vibration and noise, and perform fault diagnosis and prediction in combination with a preset fault mode library. This step aims to detect potential problems early and prevent faults from occurring or expanding.

[0067] Dynamic adjustment and optimization (step S5):

[0068] According to the results of the status analysis, the controller will dynamically adjust the output voltage, frequency and phase of the inverter. This adjustment is based on a deep understanding of the current operating status of the water pump and future demand trends, aiming to make the water pump run at the optimal operating parameters, thereby improving its operating efficiency and stability.

[0069] The dynamic adjustment process is a closed loop, that is, the system will continuously monitor the effect of the adjustment and further optimize the control strategy based on the feedback results to achieve adaptive control.

[0070] It should be noted that the starting threshold condition in step S1 is set based on the design specifications, historical operating data and safety standards of the motor to ensure that the motor starts under the best conditions; and the dynamic adjustment in step S5 is based on the real-time parameter changes during the operation of the motor, and the output parameters of the inverter are optimized in real time.

[0071] To further explain, in step S1, it also includes judging whether the line resistance, line inductance, and back electromotive force reach a first threshold, a second threshold, and a third threshold to determine whether the motor meets the starting conditions.

[0072] This adaptive control method of variable frequency water pump ensures safe and efficient starting and stable operation of the motor by comprehensively evaluating multiple electrical parameters before the motor starts and during operation. Its working principle is as follows:

[0073] Insulation resistance detection: Before starting the motor, use a megohmmeter or other tool to detect the insulation resistance of the motor winding. This value reflects the electrical isolation capability between the motor winding and the ground (or housing), and is the basis for ensuring the safe operation of the motor. Only when the insulation resistance value reaches or exceeds the preset first threshold value, the motor is considered to meet one of the starting conditions.

[0074] Inductance characteristic analysis: Although the inductance value is not a threshold parameter directly used for starting judgment, its characteristics have been fully considered in motor design. During motor operation, the presence of inductance will affect the rate of change of current, and thus affect the starting performance and dynamic response of the motor. Therefore, during the motor design stage, a suitable second threshold value will be selected according to performance requirements, and its changes will be monitored through the control system during actual operation to ensure the stability of motor performance.

[0075] Back EMF monitoring: Back EMF is a natural phenomenon during the operation of the motor, and its magnitude is related to the motor's speed and magnetic field changes. In the early stage of starting, the back EMF is small, which is conducive to the generation of starting current and starting torque. As the speed increases, the back EMF gradually increases and reaches a dynamic balance with the applied voltage. The control system monitors the changes in the back EMF, indirectly evaluates the operating status of the motor with a suitable third threshold, and takes corresponding protective measures to prevent potential damage.

[0076] Comprehensive evaluation and start-up control: After confirming that the insulation resistance meets the start-up conditions, the control system will comprehensively evaluate other electrical parameters of the motor (such as inductance characteristics and back electromotive force, etc.) to decide whether to start the motor. If all conditions meet the preset requirements, the control system will issue a start command and adjust the output voltage, frequency and phase through the inverter to optimize the starting performance of the motor.

[0077] Further explanation, the calculation of the load rate in step S4 includes measuring the actual current I of the motor 实际 And with the rated current I 额定 Compare, calculate the load factor λ and quantify the load degree;

[0078] Where λ = I 实际 / I 额定 ;

[0079] The load level is set to:

[0080] When 0≤λ<0.5, the motor is considered to be in a light load state;

[0081] When 0.5≤λ<0.8, the motor is considered to be in a medium load state;

[0082] When 0.8≤λ<1.0, the motor is considered to be in a heavy load state;

[0083] When λ≥1.0, the motor is considered to be in an overload state.

[0084] According to the value of the load rate λ, the load degree of the motor can be divided into different levels or intervals. Specifically, when it is detected that the motor load is in a heavy load state or an overload state, the output frequency of the inverter can be reduced, and the speed and output power of the water pump can be reduced.

[0085] It should be noted that these quantitative standards of load levels can be adjusted according to the needs of actual applications.

[0086] Further explanation, the evaluation efficiency in step S4 is obtained by calculating the input power Pin and the output power Pout of the motor, and comparing the two to obtain the electrical efficiency η1= and the electrical efficiency loss Lossη, and quantify the degree of loss;

[0087] Among them, input power Pin = V × I, I is the motor current, V is the voltage;

[0088] Output power Pout = ρ × g × H × Q / 3600, ρ is the fluid density, g is the acceleration of gravity, Q is the flow rate, and H is the head;

[0089] Electrical efficiency η1 = Pin / Pout × 100%;

[0090] The electrical efficiency loss Lossη is calculated by one or a combination of the following calculations:

[0091] Lossη=(η2-η1) / η2×100%, η2 is the rated electrical efficiency;

[0092] Lossη=(η3-η1) / η3×100%, η3 is the historical average electrical efficiency;

[0093] The loss level is set as:

[0094] When Lossη≤5%, it is considered that the efficiency loss of the motor is in a small state;

[0095] When Lossη>5%, it is considered that the efficiency loss of the motor is in a large state.

[0096] Specifically, calculating the input power and output power of the motor and comparing the two to obtain the electrical efficiency and its loss is an important means of evaluating the motor performance. This process not only helps to understand the energy utilization efficiency of the motor, but also provides data support for subsequent maintenance and optimization.

[0097] To further explain, monitoring the thermal state in step S4 includes using a temperature sensor and a thermal model of the motor to evaluate whether the operating temperature of the motor is close to or exceeds a maximum allowable operating temperature.

[0098] Specifically, when it is detected that the operating temperature of the motor exceeds the maximum allowable operating temperature, the operating temperature of the motor can be reduced by increasing heat dissipation measures or reducing the load.

[0099] To further explain, the analyzing electrical characteristics in step S4 includes evaluating the winding state of the motor using changes in line resistance and line inductance, and evaluating the magnetic flux and magnetic field strength of the motor using changes in back electromotive force.

[0100] In the analysis of electrical characteristics in step S3, it is crucial to deeply evaluate the winding status of the motor as well as the magnetic flux and magnetic field strength. The following is a detailed expansion of these two aspects:

[0101] 1. Winding condition assessment

[0102] Using the change in line resistance:

[0103] Measurement and recording: First, when the motor is stopped and fully cooled, use a high-precision multimeter or a special resistance tester to measure the resistance value (R1, R2, R3) of each phase winding of the motor. These values ​​should be compared with the motor's technical specifications or previous measurement records.

[0104] Analyze changes: Changes in resistance values ​​may indicate faults in the windings, such as open circuits, short circuits, or poor contacts. For example, if the resistance value of a phase increases significantly, it may mean that there is an open circuit or a high-resistance connection in the winding of that phase; if the resistance value decreases, it may indicate a short circuit in the winding or a parallel path.

[0105] Temperature correction: Considering the characteristic that resistance value changes with temperature, when comparing resistance values, the consistency of measurement conditions (such as temperature) should be ensured, or necessary temperature correction should be performed.

[0106] Using the change in line inductance:

[0107] Inductance measurement: Use an inductance meter or a network analyzer to measure the inductance of each phase winding of the motor (L1, L2, L3). The inductance value reflects the structure and magnetic coupling of the winding.

[0108] Change analysis: Changes in inductance may indicate changes in winding structure, such as turn-to-turn shorts, winding deformation, or air gap changes in the magnetic circuit. Turn-to-turn shorts will cause the inductance value to decrease because the shorted turns reduce the number of effective turns and change the flux path.

[0109] Phase-to-phase comparison: Comparing the consistency of the inductance values ​​of each phase is also an effective way to evaluate the condition of the winding. Significant inconsistency may indicate an unbalanced or faulty winding.

[0110] 2. Magnetic flux and magnetic field strength evaluation

[0111] Using an estimate of back EMF:

[0112] Definition of back electromotive force: Back electromotive force (EMF) is the electromotive force generated in the winding by the change of magnetic field when the motor rotates. It is proportional to the speed and magnetic flux of the motor.

[0113] Estimation method: When the motor is running at no load or light load, the value of the back electromotive force can be estimated by measuring the phase voltage and phase current of the motor. Usually, when the motor is running stably and the current is small, the phase voltage is approximately equal to the back electromotive force (ignoring the resistance voltage drop).

[0114] Magnetic flux evaluation: The estimated value of back EMF can be used to evaluate the magnetic flux of the motor. According to Faraday's law of electromagnetic induction, the back EMF is proportional to the rate of change of the magnetic flux. Therefore, by comparing the back EMF values ​​at different speeds or loads, the change trend of the magnetic flux can be inferred.

[0115] Magnetic field strength assessment: Although direct measurement of magnetic field strength usually requires the use of specialized magnetic field measurement equipment, it can be indirectly assessed through back-EMF and known motor parameters such as number of winding turns, number of pole pairs, etc. The magnetic field strength is related to the magnetic flux and magnetic circuit structure, and the magnetic flux can be estimated through back-EMF.

[0116] In summary, electrical characteristics analysis provides a powerful means to evaluate the winding state and magnetic flux and magnetic field strength of the motor by monitoring the changes in line resistance and line inductance and estimating the value of back electromotive force. These analyses help to timely detect potential motor failures or performance degradation problems and take corresponding maintenance or repair measures.

[0117] To further explain, the vibration and noise conditions in step S4 include monitoring the vibration and noise conditions of the motor using vibration and noise sensors to identify potential mechanical failures.

[0118] Specifically, vibration sensors are installed at key parts of the motor, such as the bearing seat, housing or shaft, to capture the vibration signals of the motor. These sensors can be accelerometers, velocity sensors or displacement sensors. Noise sensors are installed at locations that can accurately reflect the noise level of the motor, usually close to the motor but not interfered by other noise sources. Based on the values ​​collected by the vibration sensor and the noise sensor, according to the known JB-T7565.1-2004 standard, the vibration and noise levels of the motor are ensured to meet the regulations.

[0119] An adaptive control system for a variable frequency water pump, using the adaptive control method for a variable frequency water pump as described above, comprises:

[0120] The first data acquisition module is used to collect motor parameters of the variable frequency water pump, including line resistance, line inductance and back electromotive force;

[0121] A data judgment module is used to judge whether the motor parameters meet the preset starting threshold conditions at the same time, so as to determine whether the motor meets the starting conditions;

[0122] The second data acquisition module is used to collect sensor information of each sensor on the variable frequency water pump, including temperature information, vibration information and noise information, when the motor startup conditions are met;

[0123] The data processing module is used to pre-process, filter and denoise the collected motor parameters and sensor information to extract key information;

[0124] The data calculation module is used to calculate the load rate, evaluate the efficiency, monitor the thermal state, analyze the electrical characteristics and vibration and noise conditions based on the processed motor parameters and sensor information, and perform fault diagnosis and prediction to obtain the motor status analysis results; for example, when it is detected that the motor load is too heavy, the control execution module can reduce the output frequency of the inverter and reduce the speed and output power of the water pump; when it is detected that the motor temperature is too high, the temperature can be reduced by increasing heat dissipation measures or reducing the load.

[0125] The control execution module is used to dynamically adjust the output voltage, frequency and phase of the variable frequency water pump according to the motor status analysis results to optimize the operating efficiency and stability of the water pump. The control system forms a closed-loop control through continuous monitoring and adjustment to ensure that the water pump always operates in the optimal state. At the same time, the control system can also record historical data for subsequent performance analysis and optimization improvements.

[0126] The technical principle of the present invention is described above in conjunction with specific embodiments. These descriptions are only for explaining the principle of the present invention and cannot be interpreted as limiting the scope of protection of the present invention in any way. Based on the explanations herein, those skilled in the art can associate other specific embodiments of the present invention without creative work, and these equivalent variations or substitutions are all included in the scope defined by the claims of this application.

Claims

1. An adaptive control method for a variable frequency water pump, characterized in that: The following steps are involved: Step S1: collecting motor parameters of the variable frequency water pump, including line resistance, line inductance and back electromotive force; Step S2: When the motor startup conditions are met, sensor information of each sensor on the variable frequency water pump is collected, including temperature information, vibration information and noise information; Step S3: preprocessing, filtering and denoising the collected motor parameters and sensor information to extract key information; Step S4: Based on the processed motor parameters and sensor information, calculate the load rate, evaluate the efficiency, monitor the thermal state, analyze the electrical characteristics and vibration and noise conditions, and perform fault diagnosis and prediction to obtain the motor state analysis results; Step S5: According to the motor status analysis result, dynamically adjust the output voltage, frequency and phase of the inverter to optimize the operating efficiency and stability of the water pump.

2. The adaptive control method of a variable frequency water pump according to claim 1, characterized in that: In step S1, it also includes judging whether the line resistance, line inductance, and back electromotive force reach a first threshold, a second threshold, and a third threshold to determine whether the motor meets the starting conditions.

3. The adaptive control method of a variable frequency water pump according to claim 1, characterized in that: The calculation of the load factor in step S4 includes measuring the actual current I of the motor 实际 And with the rated current I 额定 Compare, calculate the load factor λ and quantify the load degree; Among them, λ=I 实际 / I 额定 ; The load level is set to: When 0≤λ<0.5, the motor is considered to be in a light load state; When 0.5≤λ<0.8, the motor is considered to be in a medium load state; When 0.8≤λ<1.0, the motor is considered to be in a heavy load state; When λ≥1.0, the motor is considered to be in an overload state.

4. The adaptive control method of a variable frequency water pump according to claim 1, characterized in that: The efficiency evaluation in step S4 is performed by calculating the input power Pin and the output power Pout of the motor, and by comparing the two to obtain the electrical efficiency η1= and the electrical efficiency loss Lossη, and quantify the degree of loss; Among them, input power Pin = V × I, I is the motor current, V is the voltage; Output power Pout = ρ × g × H × Q / 3600, ρ is the fluid density, g is the acceleration of gravity, Q is the flow rate, and H is the head; Electrical efficiency η1 = Pin / Pout × 100%; The electrical efficiency loss Lossη is calculated by one or a combination of the following calculations: Lossη=(η2-η1) / η2×100%, η2 is the rated electrical efficiency; Lossη=(η3-η1) / η3×100%, η3 is the historical average electrical efficiency; The loss level is set as: When Lossη≤5%, it is considered that the efficiency loss of the motor is in a small state; When Lossη>5%, it is considered that the efficiency loss of the motor is in a large state.

5. The adaptive control method of a variable frequency water pump according to claim 1, characterized in that: Monitoring the thermal state in step S4 includes using a temperature sensor and a thermal model of the motor to assess whether the operating temperature of the motor is close to or exceeds a maximum allowable operating temperature.

6. The adaptive control method of a variable frequency water pump according to claim 1, characterized in that: The analysis of electrical characteristics in step S4 includes evaluating the winding state of the motor using changes in line resistance and line inductance, and evaluating the magnetic flux and magnetic field strength of the motor using changes in back electromotive force.

7. The adaptive control method of a variable frequency water pump according to claim 1, characterized in that: The vibration and noise conditions in step S4 include monitoring the vibration and noise conditions of the motor using vibration and noise sensors to identify potential mechanical failures.

8. An adaptive control system for a variable frequency water pump, characterized in that: An adaptive control method for a variable frequency water pump according to any one of claims 1 to 7 is adopted, comprising: The first data acquisition module is used to collect motor parameters of the variable frequency water pump, including line resistance, line inductance and back electromotive force; The second data acquisition module is used to collect sensor information of each sensor on the variable frequency water pump, including temperature information, vibration information and noise information, when the motor startup conditions are met; The data processing module is used to pre-process, filter and denoise the collected motor parameters and sensor information to extract key information; The data calculation module is used to calculate the load rate, evaluate the efficiency, monitor the thermal status, analyze the electrical characteristics and vibration and noise conditions, and perform fault diagnosis and prediction based on the processed motor parameters and sensor information to obtain the motor status analysis results; The control execution module is used to dynamically adjust the output voltage, frequency and phase of the variable frequency water pump according to the motor status analysis results to optimize the operating efficiency and stability of the water pump.

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