A circulating water pump drag reduction and pressure increasing device and a motor control system thereof

Abstract

The application discloses a circulating water pump drag-reducing and pressure-increasing device and a motor regulating system thereof, relates to the technical field of fluid machinery and automatic control, and constructs a flow field active control system of sensing, decision-making and execution. A high-frequency pressure sensor array continuously captures pressure pulsation frequency spectrums before and after an inlet flow guide unit. The frequency spectrums are directly mapped with the vortex intensity and flow state instability degree of the impeller inlet. An intelligent decision-making module performs real-time decoupling and analysis on the frequency spectrums, identifies the characteristic frequency and energy intensity of harmful vortexes, synchronously calculates the optimal deflection angle instruction of the flow guide vane, and drives the adjustable flow guide vane to move according to the instruction. An accurate pre-whirl flow with controllable intensity is actively generated in the inlet flow field in the opposite direction of the rotation direction of the impeller, so that the flow lines are greatly smoothed before the fluid enters the impeller, and the fluid can smoothly enter the working area of the impeller at the best attack angle.

Description

Technical Field

[0001] This invention relates to the field of fluid machinery and automatic control technology, specifically to a circulating water pump drag reduction and boosting device and its motor control system. Background Technology

[0002] As the core power equipment of HVAC, industrial cooling, district heating and water supply systems, circulating water pumps account for a significant proportion of the total energy consumption of buildings and industrial operating costs. With the increasing urgency of energy conservation and emission reduction, improving the operating efficiency of water pumps has become a key technical path to reduce the total life cycle cost of the system. Although traditional centrifugal water pumps have been developed for a long time and their hydraulic design and structure have become mature, their efficiency curves usually only reach their peak near the rated operating point. Once they deviate from the design operating point, the efficiency often drops sharply. This results in the water pump working in the inefficient zone for a long time due to the dynamic changes in system load, causing huge energy waste.

[0003] Existing technologies for improving pump efficiency mainly focus on two dimensions: firstly, hydraulic structure optimization, such as installing fixed guide vanes or rectifiers before the impeller inlet to improve inflow conditions; secondly, operational control optimization, commonly employing variable frequency drive (VFD) technology to adjust pump speed to adapt to changes in external load. However, both approaches have inherent limitations. Fixed guide vanes are only effective for design conditions and cannot respond to changes in flow regime; under varying conditions, they may themselves become new sources of flow resistance. Variable frequency control is essentially a passive response based on macroscopic system parameters; its control logic does not address the essence of internal pump flow losses, namely, microscopic flow regime deterioration phenomena such as instability, pre-swirl, and boundary layer separation in the impeller inlet flow. The VFD cannot sense or suppress the generation of these internal vortices, merely adjusting the speed to match external demands, failing to fundamentally reduce drag from the physical level of the flow field.

[0004] In summary, existing technical solutions are limited to static structures or rely on macroscopic feedback, lacking intelligent control systems that make proactive and forward-looking decisions based on real-time information on the microscopic flow state within the pump. Therefore, developing an integrated intelligent collaborative pump system that can connect the internal flow field with external control has become a technical challenge that urgently needs to be solved in this field. Summary of the Invention

[0005] The present application aims at solving the problems in the prior art, and provides a circulating water pump drag reduction and pressure increasing device and a motor control system thereof.

[0006] The present application aims at solving the problems in the prior art, and provides a circulating water pump drag reduction and pressure increasing device and a motor control system thereof.

[0007] The circulating water pump body is used for providing fluid conveying power, and comprises a pump shell, an impeller and a driving motor.

[0008] The fluid dynamics optimization module is integrally arranged in the pump shell flow channel, and comprises an inlet flow guide unit, an internal flow stabilizing unit and an outlet diffuser unit.

[0009] The inlet flow guide unit is arranged upstream of the impeller inlet, and is used for aggregating and guiding the fluid flowing into the pump shell to the impeller.

[0010] The internal flow stabilizing unit is arranged corresponding to the working area of the impeller, and is used for guiding the fluid to form a spiral stable flow state to reduce the frictional resistance of the flow channel.

[0011] The outlet diffuser unit is arranged downstream of the impeller outlet, and is used for converting the fluid kinetic energy into pressure energy.

[0012] Further, the inlet flow guide unit is a group of adjustable flow guide vanes, and the adjustable flow guide vanes are configured to be synchronously adjusted in mounting angle, so as to actively generate a pre-rotation flow opposite to the rotation direction of the impeller, for canceling the harmful vortex at the impeller inlet and optimizing the inlet flow attack angle.

[0013] Further, the internal flow stabilizing unit is a micro vortex generator group attached to the inner wall of the pump shell and the surface of the impeller flow channel, and the arrangement mode of the micro vortex generator group is adapted to the pre-rotation flow line direction generated by the adjustable flow guide vanes, for stabilizing the boundary layer and inhibiting flow separation.

[0014] Further, the outlet diffuser unit is an asymmetric diffuser, whose cross-sectional expansion rate varies along the circumference, and its asymmetry matches the intensity distribution of the spiral stable flow state, to maximize the kinetic energy recovery efficiency and reduce the vortex loss.

[0015] In another aspect, a motor control system for a circulating water pump drag reduction and pressure increasing device, the system comprises:

[0016] a flow field sensing module for collecting dynamic pressure signals of the fluid near the fluid dynamics optimization module in real time;

[0017] an intelligent decision-making module connected to the flow field sensing module, configured to perform real-time spectral analysis on the received dynamic pressure signals, and extract characteristic parameters representing the degree of flow field instability, based on the pre-stored optimal mapping relationship, and according to the characteristic parameters, synchronously calculate two control outputs (α * ,n * ), wherein the α * is the target angle of the guide vane for optimizing the flow field, and the n * is the target speed of the motor for matching the system demand;

[0018] a cooperative execution module connected to the output end of the intelligent decision-making module, including a first execution sub-module and a second execution sub-module, for receiving the target angle of the guide vane and the target speed of the motor, and driving the guide vane and the motor of the circulating water pump drag reduction and pressure increasing device to operate at the specified angle and speed.

[0019] Further, the flow field sensing module includes two high-frequency dynamic pressure sensor groups, wherein:

[0020] the first sensor group is arranged at the upstream inlet of the inlet guide unit, for collecting the original pressure fluctuation signal P in (t) of the incoming flow;

[0021] the second sensor group is arranged between the internal flow stabilizing unit and the impeller, for collecting the optimized flow field pressure signal P opt (t);

[0022] the intelligent decision-making module accurately evaluates the flow field optimization effect and instability degree by comparing and analyzing the spectral feature differences between P in (t) and P opt (t), i.e., performing fast Fourier transform on the original pressure fluctuation signal P in (t) and the flow field pressure signal P opt (t) respectively, to obtain the frequency domain energy distribution and wherein, Ein (f) and E opt (f) are the original pressure fluctuation signals P in (t) and the optimized flow field pressure signals P opt (t) at frequency f, T is the sampling time period, j is the imaginary unit, f is the frequency variable, a characteristic frequency interval [f1, f2] is set, which corresponds to the dominant frequency of the impeller inlet vortex and flow separation, and a flow field instability degree index ΔE is defined as: where f max is the upper limit of the analysis frequency, ΔE is a normalized measure of the energy change in the characteristic frequency interval, and the larger the value, the more significant the flow field optimization effect or the more serious the incoming flow instability.

[0023] Further, the optimal mapping relationship pre-stored in the intelligent decision module is a multivariate coupling function model, which is used to couple the corresponding relationship between the flow field characteristic parameters, the guide vane angle and the motor speed. The expression form of the multivariate coupling function model is: * , n * ) = F(ΔE, Q d ), where α * is the optimal guide vane target angle solved, which is used to adjust the inlet guide vane blade angle to optimize the flow field, n * is the optimal motor target speed solved, which is used to drive the driving motor of the circulating water pump, Q d is the system demand flow instruction including the target flow and the target pressure, ΔE is the flow field instability degree index, and the function F is obtained by training based on the machine learning algorithm of historical data, taking the mean square error MSE as the loss function. The where N is the number of training samples,

[0024] and are the i-th group of guide vane angles and motor speeds predicted by the model respectively, and are the i-th group of guide vane angles and motor speeds actually measured respectively, and MSE makes the function F output the control instruction combination (α d , n total ) that makes the total efficiency η * of the circulating water pump system highest under the given ΔE and Q * .

[0025] Further, the first execution submodule output end is connected with the adjustable guide vane in the inlet guide unit, for receiving the optimal guide vane target angle α * instruction and driving the adjustable guide vane to move to the specified angle.

[0026] Further, the second execution sub-module output end is electrically connected with the driving motor of the circulating water pump drag reduction and pressure increasing device, and since the optimal motor target rotating speed n * The instructions control the driving motor of the circulating water pump drag reduction and pressure increasing device to rotate to a specified rotating speed by changing the frequency of the output power supply.

[0027] Compared with the prior art, the circulating water pump drag reduction and pressure increasing device and the motor regulation system have the following beneficial effects:

[0028] Firstly, the application constructs a flow field active control system with sensing, decision-making and execution, the high-frequency pressure sensor array continuously captures the pressure fluctuation spectrum before and after the inlet flow guide unit, the spectrum features have a direct mapping relationship with the vortex intensity and flow instability degree of the impeller inlet, the intelligent decision-making module performs real-time decoupling and analysis on the spectrum, identifies the characteristic frequency and energy intensity of harmful vortex, and synchronously calculates the optimal deflection angle instruction of the adjustable flow guide vane, the instruction drives the adjustable flow guide vane to act, and an accurate pre-whirl flow with controllable intensity in the opposite direction of the impeller rotation is actively generated in the inlet flow field, so that the adverse pre-whirl and vortex induced by the suction effect of the impeller rotation on the incoming flow are offset from the nature of fluid dynamics, and the flow lines are greatly smoothed before the fluid enters the impeller, so that the fluid can smoothly enter the impeller working area at the best attack angle.

[0029] Secondly, the double-variable collaborative regulation strategy realizes the linkage of the flow field physical parameters and the motor electrical parameters, the optimal mapping model in the intelligent decision-making module takes the flow field instability degree index and the external demand flow as joint inputs, and parallelly calculates the only optimal combination of the flow guide vane angle and the motor rotating speed, and this mechanism ensures that the flow state in the water pump is actively maintained in the high-efficiency interval under any working condition, and the energy input of the motor accurately corresponds to the optimized flow field load, so that the optimization of fluid mechanics and the optimal solution of electrical control are accurately matched and dynamically balanced at each decision-making moment.

[0030] Other advantages, objects, and features of the application will be apparent to those skilled in the art from the following specification and drawings, and it is intended to cover any alternatives, modifications, or equivalents included within the scope of the following claims. BRIEF DESCRIPTION OF DRAWINGS

[0031] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or the prior art description. Obviously, the drawings in the following description are only some embodiments of the present application, and those skilled in the art can also obtain other drawings according to these drawings without any creative effort.

[0032] Figure 1 A flow chart of a motor control system of a circulating water pump drag reduction and pressure increasing device;

[0033] Figure 2 An execution logic diagram of a circulating water pump drag reduction and pressure increasing device;

[0034] Figure 3 An execution logic diagram of a motor control system of a circulating water pump drag reduction and pressure increasing device. DETAILED DESCRIPTION

[0035] In order to further illustrate the technical means and effects adopted by the present application to achieve the predetermined object of the present application, the specific embodiments, structures, features and effects according to the present application will be described in detail below in combination with the drawings and preferred embodiments.

[0036] Embodiment one

[0037] This embodiment describes in detail the working principle of a circulating water pump drag reduction and pressure increasing device and its motor control system. The device provides fluid conveying power through the circulating water pump main body, optimizes the flow field in the pump relying on the fluid dynamics optimization module, and realizes the collaborative control of the flow field and the motor in combination with the motor control system.

[0038] The circulating water pump drag reduction and pressure increasing device comprises a circulating water pump main body and a fluid dynamics optimization module. The circulating water pump main body provides sufficient power for fluid conveying and is mainly composed of a pump shell, an impeller and a driving motor. The pump shell is used to ensure that the fluid can smoothly enter the impeller and smoothly flow out after the impeller works. The impeller is used to realize the energy conversion of the fluid. The impeller is driven to rotate by the driving motor. The driving motor and the impeller are connected through a shaft coupling. When the driving motor starts, the mechanical energy output by the motor is transmitted to the impeller through the shaft coupling, so that the impeller rotates at high speed. When the impeller rotates, the blades of the impeller generate force on the fluid, converting mechanical energy into kinetic energy and pressure energy of the fluid, thereby pushing the fluid to flow in the flow passage inside the pump shell, realizing the conveying of the fluid.

[0039] The fluid dynamics optimization module is integrally arranged in the flow passage of the pump shell, as shown in Figure 2 The fluid dynamics optimization module comprises an inlet flow guide unit, an internal flow stabilizing unit and an outlet pressure recovery unit. By optimizing the flow field distribution in the pump, the frictional resistance of the flow passage is reduced, and the energy conversion efficiency of the fluid is improved. The inlet flow guide unit is arranged upstream of the impeller inlet and adopts a structure of a group of adjustable flow guide vanes. The installation angle of the adjustable flow guide vanes can be synchronously adjusted. According to the real-time changes of the flow field in the pump, the blade angle is actively adjusted to generate a pre-rotation flow opposite to the rotation direction of the impeller. Specifically, during the operation, when the fluid is about to enter the impeller inlet, the inlet flow guide unit starts to work. The adjustable flow guide vanes are driven by the subsequent collaborative execution module and adjust the target angle of the flow guide vanes according to the calculation of the intelligent decision module.*The installation angle is adjusted, the blade angle is changed, the fluid flowing in forms a specific pre-rotation flow state before entering the impeller, the direction of the pre-rotation flow is opposite to the rotation direction of the impeller, the harmful vortex generated by the rotation of the impeller at the inlet of the impeller can be effectively offset, the harmful vortex can cause the fluid to flow turbulently at the inlet of the impeller, increase the flow resistance of the fluid, reduce the working efficiency of the impeller on the fluid, and can also cause vibration and noise of the impeller, and the pre-rotation flow generated by the inlet guide unit can optimize the attack angle of the fluid entering the impeller, so that the fluid enters the flow passage between the impeller blades at a more stable and reasonable angle, reduces the impact loss between the fluid and the blades, and lays a good foundation for the subsequent high-efficiency working of the impeller; the internal flow stabilizing unit is arranged corresponding to the working area of the impeller, adopts the structure form of the micro vortex generator group attached to the inner wall of the pump shell and the surface of the impeller flow passage, and is based on the boundary layer theory in fluid mechanics. When the fluid flows in the pump shell flow passage and the impeller flow passage, a boundary layer is formed in the area close to the wall surface. With the flow of the fluid, the boundary layer gradually thickens, and flow separation is prone to occur. Flow separation can generate a large amount of vortex flow in the flow passage, which consumes the energy of the fluid and increases the flow resistance, seriously affecting the operating efficiency of the water pump. The internal flow stabilizing unit can generate a series of small vortex flows in the boundary layer. These small vortex flows can enhance the momentum exchange of the fluid in the boundary layer, introduce the fluid with high kinetic energy outside the boundary layer into the boundary layer, supplement the energy of the fluid in the boundary layer, thereby delaying the thickening speed of the boundary layer and inhibiting the occurrence of flow separation. At the same time, these small vortex flows can also disturb the main flow field to some extent, so that the fluid flowing in the flow passage is more uniform and stable, forming a spiral stable flow state, further reducing the friction resistance of the flow passage and improving the flow efficiency of the fluid in the flow passage; the outlet diffuser unit is arranged downstream of the impeller outlet and adopts the structure form of an asymmetric diffuser. The flow passage cross-sectional expansion rate of the asymmetric diffuser changes along the circumference, and the asymmetry thereof matches the strength distribution of the spiral stable flow state formed by the internal flow stabilizing unit. This matching design is to realize the efficient conversion of fluid kinetic energy into pressure energy and reduce vortex loss. After the fluid passes through the impeller and does work, it obtains a large kinetic energy and flows out of the impeller outlet at a high speed. At this time, the kinetic energy of the fluid accounts for a large proportion, and the pressure energy is relatively small, which cannot meet the requirements of the subsequent pipeline conveying. The outlet diffuser unit uses the expansion of the flow passage cross section of the diffuser to gradually reduce the speed of the fluid during flow. When the fluid flows through the gradually expanding pipeline of the flow passage cross section, the speed of the fluid will decrease accordingly, and the pressure will increase accordingly, so as to realize the conversion of kinetic energy into pressure energy. Since the outlet diffuser unit adopts an asymmetric design and the asymmetry thereof matches the strength distribution of the spiral stable flow state, the speed and pressure of the fluid at each circumferential position in the diffuser can change more uniformly, avoiding vortex loss caused by uneven flow field distribution, maximizing the kinetic energy recovery efficiency, and ensuring that the fluid flows out of the pump shell at a required pressure and speed and enters the subsequent pipeline system for conveying.

[0040] The motor control system is suitable for the above-mentioned circulating water pump drag reduction and pressure increasing device, mainly composed of a flow field sensing module, an intelligent decision module and a collaborative execution module, through real-time sensing of the flow field state in the pump, intelligent decision of the optimal control parameters, and driving of the related components to execute the control actions, realizing the collaborative matching of the flow field optimization and the motor operation, and ensuring that the circulating water pump is always in an efficient operation state.

[0041] The flow field sensing module is used for real-time acquisition of dynamic pressure signals of fluid near the fluid dynamics optimization module, mainly including two high-frequency dynamic pressure sensor groups, wherein the first sensor group is arranged at the upstream inlet of the inlet flow guide unit, and the installation position is selected to be able to acquire the original pressure fluctuation signal P in (t) of the incoming flow without optimization by the inlet flow guide unit, the first sensor group continuously acquires the pressure fluctuation signal of the incoming flow at a fixed sampling frequency through high-frequency data acquisition technology, and converts the acquired analog signal into a digital signal and transmits it to the intelligent decision module; the second sensor group is arranged between the internal flow stabilizing unit and the impeller, and this position can acquire the flow field pressure signal P opt (t) after preliminary optimization by the inlet flow guide unit and the internal flow stabilizing unit, the second sensor group also acquires the pressure signal in a high-frequency sampling manner, and transmits the digital signal to the intelligent decision module, by arranging two sensor groups to acquire the pressure signals before and after optimization respectively, the original data support is provided for the intelligent decision module to analyze the flow field optimization effect and instability degree.

[0042] The signal input end of the intelligent decision module is connected with the flow field sensing module, real-time spectrum analysis is performed on the received dynamic pressure signal, the flow field instability degree characteristic parameter is extracted, and the optimal control output (α * ,n * ) is calculated based on the pre-stored optimal mapping relationship, specifically: the intelligent decision module first performs real-time spectrum analysis on the received original pressure fluctuation signal P in (t) and the optimized flow field pressure signal P opt (t), the purpose of spectrum analysis is to convert the pressure signal in the time domain to the frequency domain, so as to identify the characteristic frequency of harmful vortex and flow separation in the flow field, thereby evaluating the optimization effect and instability degree of the flow field, the fast Fourier transform algorithm is adopted to process P in (t) and P opt (t) respectively, the fast Fourier transform can decompose the time domain signal into the superposition of different frequency components, and the mathematical expression is as follows:

[0043] For the original pressure fluctuation signal Pin(t), after fast Fourier transform, the energy distribution E in (f) of Pin(t) in the frequency domain is obtained, and the expression is:

[0044] For the optimized flow field pressure signal P opt (t), after fast Fourier transform, the energy distribution E opt (f) in the frequency domain is obtained, and the expression is:

[0045] Wherein, T is the sampling time period, j is the imaginary unit, f is the frequency variable, E in (f) and E opt (f) respectively represent the energy distribution of the original pressure fluctuation signal and the optimized flow field pressure signal at frequency f, and through fast Fourier transform, the complex pressure fluctuation signal in the time domain can be converted into the energy value corresponding to different frequencies in the frequency domain, thereby directly reflecting the energy distribution of different frequency components in the flow field;

[0046] After obtaining E in (f) and E opt (f), the intelligent decision module sets the characteristic frequency interval [f1, f2] corresponding to the dominant frequency of the impeller inlet vortex and flow separation, and in this frequency interval, the energy change of the flow field can most directly reflect the instability degree and optimization effect of the flow field, and defines the flow field instability degree index ΔE for quantitatively evaluating the instability degree of the flow field, and the expression is: Wherein, f max is the upper limit of the analysis frequency, and the setting of the upper limit needs to ensure that all possible frequency components in the flow field can be covered, avoiding missing important flow field information due to too low upper limit of frequency, ΔE is the normalized measure of energy change in the characteristic frequency interval, and the greater the value is, the more energy reduction of the optimized flow field compared with the original flow field in the characteristic frequency interval, that is, the more significant the flow field optimization effect is; on the contrary, if ΔE is small, it indicates that the flow field optimization effect is poor, or the incoming flow instability is serious, and the control parameters need to be further adjusted. Specifically, in the embodiment, the intelligent decision module compares ΔE with the pre-stored mapping table: if ΔE>ΔE th1 (ΔE th1 is the high instability threshold, and ΔE th1 =0.6), it indicates that the harmful vortex and flow separation phenomenon in the current flow field is serious, and the inlet guide vane angle needs to be adjusted to optimize the flow field; if ΔE th2 ≤ΔE≤ΔE th1 (ΔE th2 is the low instability threshold, and ΔE th2 =0.3), it indicates that the flow field is in a moderate instability state, and the guide vane angle and motor speed need to be adjusted simultaneously; if ΔE<ΔE th2 , it indicates that the current flow field optimization effect is good, and only Q dFine-tune the motor speed to match the load requirements.

[0047] The optimal mapping relationship pre-stored in the intelligent decision module is a multi-variable coupling function model, which is used to couple the corresponding relationship among the flow field characteristic parameter (flow field instability index ΔE), guide vane angle (α), and motor speed (n). The multi-variable coupling function model is obtained by machine learning algorithm based on a large number of historical data. In the training process, first, the flow field instability index ΔE, system demand flow instruction Q d (including target flow, target pressure), and the actually measured optimal guide vane angle α true and optimal motor speed n true and other data under different working conditions are collected to form a training sample set. Then, the mean square error MSE is used as the loss function to train the multi-variable coupling function model, and the model parameters are constantly adjusted to minimize the error between the predicted value of the model and the actually measured value. The expression of the mean square error MSE is as follows: Wherein, N is the number of training samples, and are the i-th group of guide vane angle and motor speed predicted by the model, and are the i-th group of guide vane angle and motor speed actually measured, by minimizing the MSE, the multi-variable coupling function model can output the control instruction combination (α d , n total ) that makes the total efficiency η * of the circulating water pump system highest under the given ΔE and Q * .

[0048] The control input end of the cooperative execution module is connected to the output end of the intelligent decision module, including a first execution submodule and a second execution submodule, which functions to receive the guide vane target angle α and motor target speed n output by the intelligent decision module, and drive the adjustable guide vane and the driving motor of the circulating water pump to operate to the specified angle and speed. The output end of the first execution submodule is connected to the adjustable guide vane in the inlet guide unit. When the first execution submodule receives the optimal guide vane target angle α *After the instruction, the instruction is parsed to determine the angle range and direction that the adjustable guide vane needs to adjust. The first execution submodule integrates a driving mechanism (such as a servo motor, a speed reducer, etc.) and a position feedback device. After receiving the control instruction, the driving mechanism drives the adjustable guide vane to rotate around its rotating shaft according to the instruction. During the rotation of the vane, the position feedback device collects the actual position information of the vane in real time and feeds the information back to the control unit of the first execution submodule. The control unit compares the actual position information with the target angle α and adjusts the output of the driving mechanism according to the deviation value to form a closed-loop control, ensuring that the adjustable guide vane can accurately and smoothly move to the specified angle α. After the adjustable guide vane is adjusted to the target angle, it can generate the expected pre-swirl flow opposite to the rotating direction of the impeller, optimizing the inflow angle of the fluid and laying a foundation for subsequent flow field optimization. At the same time, the position feedback device continuously monitors the position of the vane. Once the vane position deviates due to external interference or other factors, the first execution submodule will adjust the driving mechanism in time to make the vane return to the target angle, ensuring the stable operation of the inlet guide unit. The output end of the second execution submodule is electrically connected with the driving motor of the circulating water pump drag reduction and pressure increasing device. When the second execution submodule receives the optimal motor target speed n * After receiving the instruction, the instruction is processed to convert the speed instruction into a corresponding motor control signal. The second execution submodule uses variable frequency speed regulation technology to control the speed of the driving motor. By changing the frequency of the output power supply, the synchronous speed of the motor is adjusted, thereby realizing the adjustment of the motor speed.

[0049] In summary, the present application realizes the efficient and stable operation of the circulating water pump through the cooperation of the fluid dynamics optimization module and the motor control system. In the fluid dynamics optimization module, the inlet guide unit aggregates and guides the fluid flowing into the pump casing to the impeller, reducing the energy loss caused by fluid impact. The internal flow stabilizing unit guides the fluid to form a spiral stable flow state, making the flow of the fluid in the pump casing more orderly and reducing the frictional resistance between the fluid and the flow passage. The outlet diffuser unit efficiently converts the kinetic energy of the fluid into pressure energy, improving the pressure increasing effect of the water pump. At the same time, the motor control system controls the driving motor speed based on the pump inlet pressure, outlet flow rate and driving motor speed data collected by the sensor group in real time. The controller accurately adjusts the driving motor speed through the frequency converter based on the preset delivery parameters, so that the water pump can quickly adapt to different working conditions. This coordinated design of control ensures that the circulating water pump can maintain a high-efficiency and stable working state under various operating conditions.

[0050] Example Two

[0051] As shown in Figure 1 Based on example one, this embodiment details the specific steps of the motor control system of the circulating water pump drag reduction and pressure increasing device in reducing the drag and increasing the pressure of the circulating water pump, which are as follows:

[0052] (1) System startup and initialization

[0053] Start the circulation pump drive motor, initialize the fluid dynamics optimization module (inlet guide vane unit, internal steady flow unit, outlet diffuser unit);

[0054] Activate the flow field sensing module, and start data collection by the high-frequency dynamic pressure sensor group;

[0055] (2) Real-time flow field data acquisition

[0056] The first sensor group (located upstream of the inlet guide vane unit) collects the original pressure fluctuation signal of the incoming flow;

[0057] The second sensor group (located between the internal steady flow unit and the impeller) collects the optimized flow field pressure signal;

[0058] (3) Flow field instability analysis and decision-making

[0059] The intelligent decision-making module compares the frequency spectrum characteristics of the two groups of pressure signals:

[0060] Perform Fast Fourier Transform (FFT) on the original signal and the optimized signal respectively, and extract the frequency domain energy distribution;

[0061] Calculate the flow field instability index (quantify the severity of vortex and flow separation) in the characteristic frequency range;

[0062] Combine the system demand flow instruction (target flow / pressure), and through the pre-trained multivariate coupling function model, simultaneously solve:

[0063] Optimal guide vane target angle (used to adjust the inlet guide vane);

[0064] Optimal motor target speed (used to adjust the drive motor);

[0065] (4) Collaborative execution of control instructions

[0066] First execution submodule: rotate the adjustable guide vane of the inlet guide vane unit to the target angle to generate reverse pre-rotation flow automatically;

[0067] Second execution submodule: adjust the drive motor power frequency through the frequency converter to make the motor speed reach the target value;

[0068] (5) Dynamic optimization and feedback loop

[0069] Real-time monitoring of the adjusted flow field pressure signal, recalculation of the flow field instability index;

[0070] If the flow field instability does not meet the expectations or the system demand changes, repeat steps (2)-(4) for dynamic adjustment;

[0071] Save run data to a history database.

[0072] The above merely describes preferred embodiments of the present application, and is not intended to limit the present application in any form. Although the present application has been disclosed with preferred embodiments as above, it is not intended to limit the present application. Any person skilled in the art can make some changes or modifications to the above disclosed technical content to obtain equivalent embodiments with equivalent changes, without departing from the technical solution of the present application. Any modification, change, and equivalent modification of the above embodiments, which does not depart from the technical solution of the present application, and which is based on the technical essence of the present application, still belongs to the scope of the technical solution of the present application.

Claims

1. A motor control system for a circulating water pump drag reduction and booster device, characterized in that, The circulating water pump drag reduction and pressurization device includes: a circulating water pump body and a fluid dynamics optimization module; the motor control system includes: a flow field sensing module, an intelligent decision-making module, and a collaborative execution module. The circulating water pump body is used to provide fluid transport power, including a pump casing, an impeller and a drive motor. The impeller is driven by the drive motor and is configured in the flow channel inside the pump casing. The fluid dynamics optimization module is integrated within the pump casing flow channel and includes an inlet flow guiding unit, an internal flow stabilizing unit, and an outlet diffuser unit. The inlet guide unit is located upstream of the impeller inlet and is used to aggregate and guide the fluid flowing into the pump casing to the impeller. The inlet guide unit is a set of adjustable guide vanes. The adjustable guide vanes are configured to have an installation angle that can be adjusted synchronously to actively generate a pre-swirling flow opposite to the impeller rotation direction, which is used to counteract the harmful vortex at the impeller inlet and optimize the inlet angle of attack. The internal flow stabilization unit is set in the working area of ​​the impeller and is used to guide the fluid to form a spiral stable flow state in order to reduce the frictional resistance of the flow channel. The outlet diffuser unit is located downstream of the impeller outlet and is used to convert fluid kinetic energy into pressure energy. The flow field sensing module is used to collect dynamic pressure signals of the fluid near the fluid dynamics optimization module in real time. The flow field sensing module includes two sets of high-frequency dynamic pressure sensors, wherein: The first sensor group is located at the upstream inlet of the inlet guide unit to collect the raw pressure pulsation signal of the incoming flow. ; The second sensor group is located between the internal flow stabilization unit and the impeller, and is used to collect the optimized flow field pressure signal. ; The intelligent decision-making module performs comparative analysis. and The differences in spectral characteristics are used to accurately evaluate the flow field optimization effect and the degree of instability, i.e., the original pressure pulsation signal. and flow field pressure signal Perform Fast Fourier Transform on each part to obtain the frequency domain energy distribution. and ,in, and These are the original pressure pulsation signals. and optimized flow field pressure signal In frequency Energy distribution at that location The sampling time period The imaginary unit, Define the characteristic frequency range for the frequency variable. This interval corresponds to the dominant frequency of impeller inlet vortex and flow separation, defining the flow field instability index. for: ,in, To analyze the upper limit of frequency, It is a normalized measure of energy variation within the characteristic frequency range; The intelligent decision-making module, whose signal input terminal is connected to the flow field sensing module, is configured to perform real-time spectrum analysis on the received dynamic pressure signal, extract feature parameters characterizing the degree of flow field instability, and simultaneously calculate two control output quantities based on a pre-stored optimal mapping relationship and the feature parameters. , wherein The target angle of the guide vanes used to optimize the flow field, the The target motor speed is used to match the system requirements. The pre-stored optimal mapping relationship is a multivariable coupling function model, which is used to couple the correspondence between flow field characteristic parameters, guide vane angle, and motor speed. The collaborative execution module, whose control input is connected to the output of the intelligent decision-making module, includes a first execution submodule and a second execution submodule, for receiving the target angle of the guide vane and the target speed of the motor, and driving the guide vane and the motor of the circulating water pump drag reduction and boosting device to run to the specified angle and speed.

2. The motor control system of the circulating water pump drag reduction and booster device according to claim 1, characterized in that, The internal flow stabilization unit is a group of micro-vortex generators attached to the inner wall of the pump casing and the surface of the impeller flow channel. Their arrangement is adapted to the streamline direction of the pre-swirling flow generated by the adjustable guide vanes, and is used to stabilize the boundary layer and suppress flow separation.

3. The motor control system of the circulating water pump drag reduction and booster device according to claim 1, characterized in that, The outlet diffuser unit is an asymmetric diffuser, whose flow cross-sectional expansion rate varies circumferentially, and its asymmetry matches the intensity distribution of the spiral stable flow state to maximize kinetic energy recovery efficiency and reduce eddy current losses.

4. The motor control system of the circulating water pump drag reduction and booster device according to claim 1, characterized in that, The multivariable coupling function model is expressed as follows: ,in, To determine the optimal target angle of the guide vanes, the inlet guide vane angle is adjusted to optimize the flow field. To determine the optimal target speed of the motor used to drive the circulating water pump, The system's required flow command includes the target flow and target load. The function is an index of flow field instability. The algorithm is trained using a machine learning method based on historical data, with mean squared error (MSE) as the loss function. ,in, The number of training samples. and The predicted numbers are respectively the first two. The angle of the guide vanes and the motor speed, and The actual measured number The angle of the guide vanes and the motor speed, Make the function In the given and The output reduces the overall efficiency of the circulating water pump system. The highest combination of control commands .

5. The motor control system of the circulating water pump drag reduction and booster device according to claim 1, characterized in that, The output of the first execution submodule is connected to the adjustable guide vane in the inlet guide unit, and is used to receive the optimal guide vane target angle. The command drives the adjustable guide vanes to move to a specified angle.

6. The motor control system of the circulating water pump drag reduction and booster device according to claim 1, characterized in that, The output of the second execution submodule is electrically connected to the drive motor of the circulating water pump drag reduction and boosting device, because it receives the optimal target motor speed. The instruction controls the drive motor of the circulating water pump drag reduction and booster device to run at a specified speed by changing the frequency of the output power supply.

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