Permanent magnet motor reforming stirring efficient energy-saving control method and system

Abstract

The application relates to the technical field of material stirring, and discloses a high-efficiency energy-saving control method and system for a permanent magnet motor reconstruction stirring device. The method comprises the following steps: S1, setting a control group operation program curve of permanent magnet motor output based on the target density of the material and the characteristics of different stages, controlling the permanent magnet motor to operate according to the control group operation program curve until the density proportion data of different depths of the material all reach the target density; S2, adjusting the rotating speed of the permanent magnet motor at different stages of the control group operation program curve to form a first control curve, and controlling the permanent magnet motor to operate according to the first control curve to stir the material; S3, obtaining the energy consumption of the material stirred by the control group operation program curve and the first control curve, and selecting one with smaller energy consumption as a second control curve; and S4, repeatedly performing steps S2 and S3 until the optimal control curve is obtained. The application can save energy as much as possible under the condition of ensuring uniform stirring.

Description

Technical Field

[0001] This invention relates to the field of material mixing technology, specifically to a method and system for high-efficiency and energy-saving control of mixing using a permanent magnet motor. Background Technology

[0002] Mixing is a widely used industrial device used to uniformly distribute and suspend materials. The principle of mixing inevitably creates an inefficient zone where the linear velocity of the material near the mixing blades' main shaft differs significantly from that at the blade tips. This results in the material near the main shaft being relatively stationary and less fluid, making it difficult for it to achieve the same density as other materials at the same time, leading to uneven mixing.

[0003] There are two existing solutions to this problem: one is to offset the central axis of the stirring head from the central axis of the stirring tank, and the other is to change the stirring path and speed. The first method does not substantially change the stirring of the inefficient zone; it merely enlarges the inefficient zone, changing it from a linear to a planar shape, thus making the density of the inefficient zone approach that of other areas over a larger area. The second method is more complex, requiring corresponding moving and power mechanisms, which increases both cost and energy consumption. Furthermore, the presence of these moving mechanisms significantly impacts the lifespan of the stirring equipment. Summary of the Invention

[0004] To address the aforementioned shortcomings, this invention discloses a method and system for high-efficiency and energy-saving control of stirring by retrofitting a permanent magnet motor, which can save energy consumption to the greatest extent possible while ensuring uniform stirring.

[0005] The first aspect of this invention discloses a method for high-efficiency and energy-saving control of stirring equipment using a permanent magnet motor, the method comprising:

[0006] S1. Based on the target density of the material and the characteristics of different stages, set the control group running program curve of the permanent magnet motor output, control the permanent magnet motor to run according to the control group running program curve, receive the density and specific gravity data of the material at different stages and different depths during the stirring process, and compare the density and specific gravity data with the target density until the density and specific gravity data of the material at different depths all reach the target density.

[0007] S2. Adjust the rotation speed of the permanent magnet motor at different stages of the running program curve of the control group to form a first control curve. Control the permanent magnet motor to run according to the first control curve to stir the material until the density and specific gravity data of the material at different depths all reach the target density.

[0008] S3. Obtain the energy consumption of stirring the material using the control group running program curve and the first control curve, and select the one with the smaller energy consumption as the second control control curve.

[0009] S4. Repeat steps S2 and S3 multiple times until the optimal control curve is obtained.

[0010] As an optional implementation, in the first aspect of the present invention, the different stages, in the order of operation of the permanent magnet motor, are, in sequence, the material static start-up stage, the material movement until uniform distribution stage, and the material uniformly distributed and kept suspended without settling stage; a control group operation program curve for the output of the permanent magnet motor is set based on the target density of the material and the characteristics of different stages, including:

[0011] During the material static start-up phase, the permanent magnet motor outputs low speed and high torque to suspend most of the material.

[0012] During the stage where the material moves until it is evenly distributed, the rotational speed of the permanent magnet motor is gradually increased while maintaining the frequency vibration, so that the material in the low-efficiency stirring zone can achieve a relative motion state through vibration.

[0013] During the stage where the material is evenly distributed and kept suspended without settling, the permanent magnet motor maintains the minimum suspension speed and increases the relative motion of the material by vibrating at preset intervals.

[0014] As an optional implementation, in the first aspect of the present invention, collecting density and specific gravity data of the material at different stages and depths during the stirring process includes:

[0015] Two or more hydrometers are installed in the mixing container used for material mixing, and the hydrometers are distributed along the height direction of the mixing container.

[0016] Set the data collection time points based on the material and viscosity characteristics;

[0017] The density and specific gravity data of the material at different stages and depths during the stirring process are collected using the hydrometer at the collection time point.

[0018] As an optional implementation, in the first aspect of the present invention, until the density specific gravity data of the material at different depths all reach the target density, it includes:

[0019] When the absolute value of the difference between the density and specific gravity data collected by all hydrometers in the mixing container and the target density is less than or equal to a preset threshold, it is determined that the density and specific gravity data of the material at different depths have reached the target density.

[0020] As an optional implementation, in a first aspect of the present invention, adjusting the rotational speed of the permanent magnet motor at different stages of the operating program curve of the control group to form a first control curve includes:

[0021] Based on the rotational speed at different stages of the control group's operating program curve, a certain amount of change is added or subtracted to form multiple first control curves;

[0022] Obtain the energy consumption of stirring the material using the control group's running program curve and the first control curve, and select the one with the lower energy consumption as the second control control curve, including:

[0023] By comparing the energy consumption of the control group's operating program curve and each first control curve at each stage, the one with the lowest energy consumption among the control group's operating program curve and multiple first control curves is selected as the second control control curve.

[0024] As an optional implementation, in the first aspect of the present invention, the method further includes:

[0025] The liquid level information of the stirring container is collected. When the liquid level rise in the stirring container reaches a preset value, the permanent magnet motor is controlled to return to the material static start-up stage and restart the stirring operation.

[0026] The second aspect of this invention discloses a high-efficiency and energy-saving control system for retrofitting a stirring machine with a permanent magnet motor, comprising:

[0027] The control unit is used to set the control group running program curve of the permanent magnet motor output based on the target density of the material and the characteristics of different stages, control the permanent magnet motor to run according to the control group running program curve, receive the density and specific gravity data of the material at different stages and different depths during the stirring process, and compare the density and specific gravity data with the target density until the density and specific gravity data of the material at different depths all reach the target density.

[0028] The adjustment unit is used to adjust the rotation speed of the permanent magnet motor at different stages of the running program curve of the control group to form a first control curve, and control the permanent magnet motor to run according to the first control curve to stir the material until the density and specific gravity data of the material at different depths all reach the target density.

[0029] The comparison unit is used to obtain the energy consumption of stirring the material using the control group running program curve and the first control curve, and select the one with the smaller energy consumption as the second control control curve.

[0030] The repeat unit is used to repeatedly adjust and compare the units until the optimal control curve is obtained.

[0031] A third aspect of the present invention discloses a SCADA system, comprising: a memory storing executable program code; a processor coupled to the memory; the processor calling the executable program code stored in the memory to execute a high-efficiency and energy-saving control method for retrofitting a permanent magnet motor for stirring, as disclosed in the first aspect of the present invention.

[0032] The fourth aspect of this invention discloses a computer-readable storage medium storing a computer program, wherein the computer program causes a computer to execute a method for high-efficiency and energy-saving control of stirring by retrofitting a permanent magnet motor, as disclosed in the first aspect of this invention.

[0033] The fifth aspect of this invention discloses a high-efficiency and energy-saving control system for agitation modified with a permanent magnet motor, comprising: a SCADA system, a permanent magnet motor, a controller, and a hydrometer. The SCADA system is electrically connected to the permanent magnet motor via the controller. The hydrometer is installed in a mixing container. Two or more hydrometers are installed in the mixing container used for material mixing, and the hydrometers are distributed along the height direction of the mixing container. The output terminal of the hydrometer is electrically connected to the SCADA system. The SCADA system is used for:

[0034] Based on the target density of the material and the characteristics of different stages, a control group running program curve is set for the output of the permanent magnet motor. The permanent magnet motor is controlled to run according to the control group running program curve. The density and specific gravity data of the material at different stages and depths during the stirring process are collected by the hydrometer. The density and specific gravity data are compared with the target density until the density and specific gravity data of the material at different depths all reach the target density.

[0035] The rotational speed of the permanent magnet motor is adjusted at different stages of the running program curve of the control group to form a first control curve. The permanent magnet motor is controlled to run according to the first control curve to stir the material until the density and specific gravity data of the material at different depths all reach the target density.

[0036] The energy consumption of stirring the material using the control group running program curve and the first control curve is obtained, and the one with the smaller energy consumption is selected as the second control control curve.

[0037] Repeat the above adjustments multiple times until the optimal control curve is obtained.

[0038] As an optional implementation, in the first aspect of the present invention, the system further includes: a liquid level sensor, which is installed on the stirring container and is used to collect the liquid level position of the material and send the liquid level position information to the SCADA system;

[0039] The SCADA system also automatically calculates the current volume and load ratio of the liquid in the tank based on changes in liquid level sensor data and changes in permanent magnet motor current and voltage data, and automatically adjusts the motor speed and operating curve to keep the motor speed at the optimal operating speed and the lowest suspension speed.

[0040] The SCADA system is also used to control the permanent magnet motor to return to the material static start-up stage and restart the stirring operation when it detects an increase in the current of the permanent magnet motor or a rise in the liquid level, until the material is evenly distributed.

[0041] The sixth aspect of this invention discloses a computer program product that, when run on a computer, causes the computer to execute a high-efficiency and energy-saving control method for retrofitting a permanent magnet motor for stirring, as disclosed in the first aspect of this invention.

[0042] The seventh aspect of this invention discloses an application publishing platform for publishing computer program products. When the computer program product is run on a computer, the computer executes a method for high-efficiency and energy-saving control of stirring by retrofitting a permanent magnet motor, as disclosed in the first aspect of this invention.

[0043] Compared with the prior art, the embodiments of the present invention have the following beneficial effects:

[0044] This invention employs a permanent magnet motor that outputs high torque at low speed during the initial static material startup phase, suspending most of the material. As the material moves and becomes evenly distributed, the motor's speed is gradually increased while maintaining frequency vibration, bringing the material in the inefficient mixing zone into relative motion through vibration. During the stage where the material is evenly distributed and suspended without settling, the permanent magnet motor maintains the minimum suspension speed, and frequency vibration at preset intervals increases the relative motion of the material, achieving uniform mixing. Furthermore, by repeatedly adjusting the control curve to achieve the optimal control curve for subsequent mixing operations with the same material, energy consumption can be significantly reduced. Attached Figure Description

[0045] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0046] Figure 1 This is a schematic flowchart of a method for controlling the high efficiency and energy saving of a stirring machine by retrofitting a permanent magnet motor, as disclosed in an embodiment of the present invention.

[0047] Figure 2This is a schematic diagram of the structure of the stirring device disclosed in the embodiment of the present invention;

[0048] Figure 3 This is a schematic diagram of the optimal control curve disclosed in the embodiments of the present invention;

[0049] Figure 4 This is a schematic diagram of the structure of a high-efficiency and energy-saving control device for retrofitting a stirring machine using a permanent magnet motor, as disclosed in an embodiment of the present invention.

[0050] Figure 5 This is a schematic diagram of a high-efficiency and energy-saving control system for retrofitting a stirring machine using a permanent magnet motor, as disclosed in an embodiment of the present invention.

[0051] Figure 6 This is a schematic diagram of the structure of a SCADA system disclosed in an embodiment of the present invention. Detailed Implementation

[0052] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0053] It should be noted that the terms "first," "second," "third," "fourth," etc., in the specification and claims of this invention are used to distinguish different objects, not to describe a specific order. The terms "comprising" and "having," and any variations thereof, in the embodiments of this invention are intended to cover non-exclusive inclusion. Exemplarily, a process, method, system, product, or device that includes a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to these processes, methods, products, or devices.

[0054] This invention discloses a method and system for high-efficiency and energy-saving control of stirring by retrofitting a permanent magnet motor. During the initial static start-up phase, the permanent magnet motor outputs high torque at low speed to suspend most of the material. As the material moves and becomes evenly distributed, the motor's speed is gradually increased while maintaining frequency vibration, allowing the material in the inefficient stirring zone to achieve relative motion through vibration. During the stage where the material is evenly distributed and suspended without settling, the permanent magnet motor maintains the minimum suspension speed, and frequency vibration is performed at preset intervals to increase the relative motion of the material, achieving uniform stirring. Based on this, the control curve is adjusted multiple times to optimize the subsequent stirring operation of the same material, thereby significantly reducing energy consumption. The following is a detailed description with reference to the accompanying drawings.

[0055] Example 1

[0056] Please see Figure 1 , Figure 1 This is a flowchart illustrating a method for high-efficiency and energy-saving control of a stirring system using a permanent magnet motor, as disclosed in an embodiment of the present invention. The method described in this embodiment is executed by a SCADA system, which can receive core data from the permanent magnet motor, such as motor current and voltage, as well as density, specific gravity, and liquid level information collected by a hydrometer and liquid level sensor. Furthermore, it can control the speed and torque of the permanent magnet motor to achieve uniform stirring of materials. Based on this, multiple control curves for the permanent magnet motor are obtained by repeatedly adjusting the motor parameters, and the optimal control curve is selected to control the permanent magnet motor, thereby reducing energy consumption. Figure 1 As shown, the method for modifying a permanent magnet motor for efficient and energy-saving control of a stirring mixer includes the following steps:

[0057] S110, based on the target density of the material and the characteristics of different stages, a control group running program curve is set for the output of the permanent magnet motor. The permanent magnet motor is controlled to run according to the control group running program curve to stir the material. The density and specific gravity data of the material at different stages and different depths during the stirring process are received, and the density and specific gravity data are compared with the target density until the density and specific gravity data of the material at different depths all reach the target density.

[0058] Mixing is a widely used industrial device that distributes materials evenly and keeps them in a suspended state; it is also called a mixer or mixing equipment.

[0059] Please refer to Figure 2 As shown, the stirring device may include a motor 210, a stirring mechanism 220, a stirring container 230, and a transmission mechanism 240. In this invention, the motor 210 is used to drive the stirring mechanism 220 to rotate in the stirring container. The motor 210 is a permanent magnet motor. The stirring mechanism 220 includes a main shaft and blades mounted on the lower side of the main shaft. The transmission mechanism 240 is used to transmit the rotation of the motor 210 to the stirring mechanism 220, and can be implemented by a belt or chain, etc.

[0060] The stirring speed has a significant impact on the efficiency, quality, and energy consumption of the entire stirring process. Different materials require different suspension speeds due to their varying viscosity, density, and resistance.

[0061] The torque and rotational speed required for the same material to achieve uniform distribution vary from the start of mixing to the initial stage. At the beginning of mixing, the material is not yet uniformly distributed, has high viscosity, and poor flowability, requiring a large torque and a low rotational speed. To suspend most of the material, the rotational speed should be gradually increased until over 98% of the material is suspended and mixed. After uniform distribution, only a minimum suspension rotational speed needs to be maintained. Adjusting to a higher speed will increase energy consumption. Furthermore, when the material is uniformly distributed, the friction between different components decreases. If the rotational speed is too high, the centrifugal force is large, and the inertial forces of different particle sizes within the material differ. When the rotational speed is too high, the inertial force exceeds the friction between the blades, causing different components to be thrown away from the blades at different speeds, resulting in material segregation and a decrease in the mixing degree. Exceeding a certain value may even cause excessive segregation and stratification. Conversely, too low a rotational speed will not suspend all the material, leading to sedimentation. Therefore, the mixing motor has a dynamic speed adjustment process that can meet the needs of mixing production while maintaining low energy consumption and high efficiency.

[0062] The principle of stirring inevitably leads to an inefficient zone. The linear velocity of the material near the main shaft of the stirring blades and at the blade tips differs greatly, causing the material near the main shaft to be in a relatively static and less fluid state. At this time, the variation of the motor speed will break the inertial velocity of the material flow, making the relative motion between adjacent particles more obvious, thereby improving the stirring efficiency and shortening the time process from uneven to uniform material distribution.

[0063] Based on this, the entire stirring process can be divided into three working stages:

[0064] Phase 1: Material Static Start-up Phase. In this phase, the permanent magnet motor starts at a low speed with high torque output, which allows most of the material to be suspended.

[0065] The second stage: material movement until uniform distribution. In this stage, the speed of the permanent magnet motor gradually increases and maintains frequency vibration, which brings the material in the low-efficiency stirring zone into a state of relative motion through vibration, thereby accelerating the fusion and distribution process;

[0066] The third stage: maintaining uniform material distribution and preventing settling. In this stage, the permanent magnet motor maintains the minimum suspension speed, and frequency vibration is performed periodically to increase the relative motion of the material and prevent it from settling.

[0067] With this control method, the materials being stirred can move in a more complex relative motion than ordinary stirring methods. There are both stable large-scale circulation movements and relatively countercurrent small-scale circulation movements, which ensures the number of cycles and enhances the stirring effect, promotes full contact and strong collision between the components of the materials, and thus the materials are evenly mixed throughout the entire stirring space.

[0068] Based on this, the control group running program curve Q0 of the permanent magnet motor output can be set according to the target density of the material and the characteristics of different stages. In the material static start-up stage, the starting speed of the control group running program curve Q0 can be set to 500 r / min. Of course, in other embodiments, it can also be set to other values. The torque can be set to the maximum torque of the permanent magnet motor or a corresponding proportion of the maximum torque, such as 80%.

[0069] During the material movement and uniform distribution stage, the rotational speed of the permanent magnet motor can be adjusted according to a predetermined speed increment, such as increasing the speed by 5-50 revolutions per minute. In this stage, the blades also maintain a certain frequency of vibration to bring the material in the inefficient mixing zone into a state of relative motion, thereby accelerating the fusion and distribution process.

[0070] The specific control group running procedure curve Q0 can be set based on experience, or multiple different control group running procedure curves Q0 can be set based on commonly used materials or the target density achieved by the materials. The target control group running procedure curve is determined by setting the correlation between the material or target density and the control group running procedure curve Q0.

[0071] In a preferred embodiment of the invention, during the experiment, multiple hydrometers can be installed in the stirring container, preferably evenly distributed along the height of the container. The stirring effect is determined by monitoring the density and specific gravity data collected by these hydrometers. In subsequent routine stirring processes, the optimal control curve determined during the experiment can be used directly without the need to install hydrometers.

[0072] Different materials and viscosity characteristics can be used to divide the working phase into different time intervals. For example, in the stirring process of a certain material, the static start-up phase may last for 1 minute, while in the stirring process of another material, the static start-up phase may last for 2 minutes. Therefore, corresponding data collection time points can be set according to the material and viscosity characteristics, and density and specific gravity data collected by multiple hydrometers installed above can be received at these collection points.

[0073] Assuming the target density of the material is ρ0, if the material reaches ρ0 when sampled at different depths (or the deviation from the target density ρ0 is less than a preset threshold), it means that the material has been mixed evenly.

[0074] S120. Adjust the rotational speed of the permanent magnet motor at different stages of the operating program curve of the control group to form a first control curve. Control the permanent magnet motor to run according to the first control curve to stir the material until the density and specific gravity data of the material at different depths all reach the target density.

[0075] The method for adjusting the speed of the permanent magnet motor at different stages of the control group's operating program curve is to increase or decrease a certain amount of change based on the speed at different stages of the control group's operating program curve, thereby forming multiple first control curves.

[0076] This certain amount of change can be set as needed, for example, it can be a change of 5r-50r per minute. For example, increasing the speed of the control group's operating program curve in the first stage by 10r / min, decreasing the speed of the control group's operating program curve in the second stage by 10r / min, and decreasing the speed of the control group's operating program curve in the third stage by 10r / min will yield the first first control curve. Alternatively, decreasing the speed of the control group's operating program curve in the first stage by 10r / min, increasing the speed of the control group's operating program curve in the second stage by 10r / min, and increasing the speed of the control group's operating program curve in the third stage by 10r / min will yield the second first control curve. In this way, multiple first control curves can be obtained.

[0077] Using a method similar to step S110, the permanent magnet motor is controlled to run according to these first control curves until the density and specific gravity data of the material at different depths all reach the target density.

[0078] S130. Obtain the energy consumption of stirring the material using the control group running program curve and the first control curve, and select the one with the smaller energy consumption as the second control control curve.

[0079] By comparing the energy consumption of the first control curve and the control group operating procedure curve at each stage of the stirring process, the control group operating procedure curve or the first control curve with the lowest energy consumption is selected as the second control control curve.

[0080] S140. Repeat steps S120 and S130 multiple times until the optimal control curve is obtained.

[0081] In some other embodiments, the second control control curve can be used as the final optimal control curve.

[0082] In a preferred embodiment of the present invention, the second control control curve can also be used as a reference curve. Following step S120, the parameters (rotation speed) at each stage are adjusted (increased or decreased by a certain amount) based on this curve. Then, the stirring process is run again, and following step S130, the curve with the lowest energy consumption is selected as the third control control curve. This third control control curve is then used as a reference curve, and the above operation is repeated multiple times, for example, 5 times, until the curve with the lowest energy consumption is finally obtained as the final optimal control curve. Figure 3This diagram illustrates the optimal control curve for a certain material, determined through multiple iterations.

[0083] As an optional implementation, a liquid level sensor can be installed on the mixing container, and the collected liquid level information data can be transmitted to a SCADA system. The SCADA system can automatically calculate the current liquid volume and load ratio in the container based on changes in the liquid level sensor data and motor current and voltage data, and automatically adjust the motor speed and operating curve to maintain the motor speed at the optimal operating speed and minimum suspension speed. In a preferred embodiment of the invention, when an increase in motor current or a rise in the liquid level in the mixing container is detected, the SCADA system centrally calculates and adjusts the curve, restarting the curve operation program from the material static start-up stage until the material is evenly distributed.

[0084] In a preferred embodiment of the present invention, a customized stirring operation curve is used, which starts with low speed and high torque, gradually accelerates, and then runs at low speed with vibration and cyclic stirring. The power consumption of the operation program is compared through statistical models and mathematical calculations to obtain the optimal solution of the operation curve, that is, to determine the optimal control curve. This minimizes energy consumption while ensuring the stirring effect.

[0085] Furthermore, the permanent magnet motor in this embodiment of the invention can achieve high-frequency variable speed oscillation operation, thereby eliminating the defects of the inefficient stirring zone.

[0086] This invention integrates a SCADA system and a sensor system (hydrometer and level sensor), achieving closed-loop feedback control. Real-time motor control is essential for this energy-saving effect. The SCADA and sensor systems monitor the material's motion and core motor data. The material distribution can be determined from the vibration of the blades and the amplitude and rise / fall of the motor current. Specifically, the liquid in the mixing container is a fluid load, characterized by its resistance to sudden changes. Therefore, during the initial static start-up phase, both the motor current amplitude and blade vibration are large, with the current rapidly increasing. As the material becomes more uniformly distributed, the current amplitude decreases, and the current value also drops. When the distribution is completely uniform, the current stabilizes as the motor begins to agitate at a relatively stable speed, resulting in a smaller current value. Therefore, by comparing the current amplitude and value with those during the stable period, the current distribution within the mixing container can be determined.

[0087] As an example, using Huakong Motor's self-developed Y132-5.5kw-960 RPM square wave permanent magnet motor to stir ceramics in an underground pool according to the above method can reduce energy consumption by 35%, achieving a good energy-saving effect.

[0088] Example 2

[0089] Please see Figure 4 , Figure 4 This is a schematic diagram of the structure of a high-efficiency and energy-saving control device for retrofitting a stirring machine using a permanent magnet motor, as disclosed in an embodiment of the present invention. Figure 4 As shown, the permanent magnet motor-modified stirring high-efficiency and energy-saving control device may include:

[0090] The control unit 310 is used to set the control group running program curve of the permanent magnet motor output based on the target density of the material and the characteristics of different stages, control the permanent magnet motor to run according to the control group running program curve, receive the density and specific gravity data of the material at different stages and different depths during the stirring process, and compare the density and specific gravity data with the target density until the density and specific gravity data of the material at different depths all reach the target density.

[0091] The adjustment unit 320 is used to adjust the rotation speed of the permanent magnet motor at different stages of the running program curve of the control group to form a first control curve, and control the permanent magnet motor to run according to the first control curve to stir the material until the density and specific gravity data of the material at different depths all reach the target density.

[0092] The comparison unit 330 is used to obtain the energy consumption of stirring the material using the control group running program curve and the first control curve, and select the one with the smaller energy consumption as the second control control curve.

[0093] The repeat unit 340 is used to repeatedly adjust and compare the unit until the optimal control curve is obtained.

[0094] Example 3

[0095] Please see Figure 5 , Figure 5 This is a schematic diagram of a high-efficiency and energy-saving control system for retrofitting a stirring machine using a permanent magnet motor, as disclosed in an embodiment of the present invention. Figure 5 As shown, the high-efficiency and energy-saving control system for retrofitting a mixing vessel using a permanent magnet motor may include: a SCADA system 410, a permanent magnet motor 420, a controller 430, and a hydrometer 440. The SCADA system is electrically connected to the permanent magnet motor via the controller. The hydrometer is installed in the mixing container. Two or more hydrometers are installed in the mixing container used for material mixing, and the hydrometers are distributed along the height of the mixing container. The output of each hydrometer is electrically connected to the SCADA system. The SCADA system is used for:

[0096] Based on the target density of the material and the characteristics of different stages, a control group running program curve is set for the output of the permanent magnet motor. The permanent magnet motor is controlled to run according to the control group running program curve. The density and specific gravity data of the material at different stages and depths during the stirring process are collected by the hydrometer. The density and specific gravity data are compared with the target density until the density and specific gravity data of the material at different depths all reach the target density.

[0097] The rotational speed of the permanent magnet motor is adjusted at different stages of the running program curve of the control group to form a first control curve. The permanent magnet motor is controlled to run according to the first control curve to stir the material until the density and specific gravity data of the material at different depths all reach the target density.

[0098] The energy consumption of stirring the material using the control group running program curve and the first control curve is obtained, and the one with the smaller energy consumption is selected as the second control control curve.

[0099] Repeat the above adjustments multiple times until the optimal control curve is obtained.

[0100] Preferably, the system may further include a liquid level sensor 450, which is installed on the stirring container to collect the liquid level position of the material and send the liquid level position information to the SCADA system. The SCADA system also automatically calculates the current volume and load ratio of the liquid in the tank based on the changes in the liquid level sensor data and the changes in the current and voltage data of the permanent magnet motor, and automatically adjusts the motor speed and operating curve to keep the motor speed at the optimal operating speed and the minimum suspension speed. The SCADA system is also used to control the permanent magnet motor to return to the first stage and restart the stirring operation when it detects an increase in the current of the permanent magnet motor or a rise in the liquid level, until the material is evenly distributed.

[0101] Example 5

[0102] Please see Figure 6 , Figure 6 This is a schematic diagram of the structure of a SCADA system disclosed in an embodiment of the present invention.

[0103] like Figure 6 As shown, the SCADA system may include: a memory 510 storing executable program code; and a processor 520 coupled to the memory 510; wherein the processor 520 calls the executable program code stored in the memory 510 to execute some or all of the steps in the method for high-efficiency and energy-saving control of a permanent magnet motor-modified stirring system disclosed in Embodiment 1.

[0104] This invention discloses a computer-readable storage medium storing a computer program that enables a computer to execute some or all of the steps in the method for high-efficiency and energy-saving control of stirring by retrofitting a permanent magnet motor, as disclosed in Embodiment 1.

[0105] This invention also discloses a computer program product, wherein when the computer program product is run on a computer, the computer executes some or all of the steps in the method for high-efficiency and energy-saving control of permanent magnet motor-modified stirring disclosed in Embodiment 1.

[0106] This invention also discloses an application publishing platform, which is used to publish computer program products. When the computer program products are run on a computer, the computer executes some or all of the steps in the method for high-efficiency and energy-saving control of permanent magnet motor-modified stirring disclosed in Embodiment 1.

[0107] In various embodiments of the present invention, it should be understood that the sequence number of each process does not necessarily imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present invention.

[0108] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; they can be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment, depending on actual needs.

[0109] Furthermore, the functional units in the various embodiments of the present invention can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0110] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-accessible memory. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a memory and includes several requests to cause a computer device (which can be a personal computer, server, or network device, specifically a processor in the computer device) to execute some or all of the steps of the methods described in the various embodiments of the present invention.

[0111] In the embodiments provided by this invention, it should be understood that "B corresponding to A" means that B is associated with A, and B can be determined based on A. However, it should also be understood that determining B based on A does not mean determining B solely based on A; B can also be determined based on A and / or other information.

[0112] Those skilled in the art will understand that some or all of the steps in the various methods of the embodiments described can be implemented by a program instructing related hardware. This program can be stored in a computer-readable storage medium, including read-only memory (ROM), random access memory (RAM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), one-time programmable read-only memory (OTPROM), electrically-erasable programmable read-only memory (EEPROM), compact disc read-only memory (CD-ROM) or other optical disc storage, disk storage, magnetic tape storage, or any other computer-readable medium capable of carrying or storing data.

[0113] The above provides a detailed description of a method and system for high-efficiency and energy-saving control of permanent magnet motor-modified stirring, as disclosed in the embodiments of the present invention. Specific examples have been used to illustrate the principles and implementation methods of the present invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of the present invention. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of the present invention. Therefore, the content of this specification should not be construed as a limitation of the present invention.

Claims

1. A method for high-efficiency and energy-saving control of stirring by retrofitting a permanent magnet motor, characterized in that, include: S1. Based on the target density of the material and the characteristics of different stages, set the control group running program curve of the permanent magnet motor output, control the permanent magnet motor to run according to the control group running program curve, receive the density and specific gravity data of the material at different stages and different depths during the stirring process, and compare the density and specific gravity data with the target density until the density and specific gravity data of the material at different depths all reach the target density. S2. Adjust the rotation speed of the permanent magnet motor at different stages of the running program curve of the control group to form a first control curve. Control the permanent magnet motor to run according to the first control curve to stir the material until the density and specific gravity data of the material at different depths all reach the target density. S3. Obtain the energy consumption of stirring the material using the control group running program curve and the first control curve, and select the one with the smaller energy consumption as the second control control curve. S4. Repeat steps S2 and S3 multiple times until the optimal control curve is obtained; The different stages, arranged in the order of the permanent magnet motor's operation, are: the material static start-up stage, the material movement until uniform distribution stage, and the material uniformly distributed and suspended without settling stage. A control group operating program curve for the permanent magnet motor output is set based on the target density of the material and the characteristics of each stage, including: During the material static start-up phase, the permanent magnet motor outputs low speed and high torque to suspend most of the material. During the stage where the material moves until it is evenly distributed, the rotational speed of the permanent magnet motor is gradually increased while maintaining the frequency vibration, so that the material in the low-efficiency stirring zone can achieve a relative motion state through vibration. During the stage where the material is evenly distributed and kept suspended without settling, the permanent magnet motor maintains the minimum suspension speed, and then vibrates at preset intervals to increase the relative motion of the material.

2. The method for high-efficiency and energy-saving control of stirring by retrofitting a permanent magnet motor according to claim 1, characterized in that, The density and specific gravity data of the material at different stages and depths during the mixing process are collected, including: Two or more hydrometers are installed in the mixing container used for material mixing, and the hydrometers are distributed along the height direction of the mixing container. Set the data collection time points based on the material and viscosity characteristics; The density and specific gravity data of the material at different stages and depths during the stirring process are collected using the hydrometer at the collection time point.

3. The method for high-efficiency and energy-saving control of stirring by retrofitting a permanent magnet motor according to claim 2, characterized in that, Until the density and specific gravity data of the material at different depths all reach the target density, including: When the absolute value of the difference between the density and specific gravity data collected by all hydrometers in the mixing container and the target density is less than or equal to a preset threshold, it is determined that the density and specific gravity data of the material at different depths have all reached the target density.

4. The method for high-efficiency and energy-saving control of stirring by retrofitting a permanent magnet motor according to claim 1, characterized in that, Adjusting the speed of the permanent magnet motor at different stages of the operating program curve of the control group to form the first control curve includes: Based on the rotational speed at different stages of the control group's operating program curve, a certain amount of change is added or subtracted to form multiple first control curves; Obtain the energy consumption of stirring the material using the control group's running program curve and the first control curve, and select the one with the lower energy consumption as the second control control curve, including: By comparing the energy consumption of the control group's operating program curve and each first control curve at each stage, the one with the lowest energy consumption among the control group's operating program curve and multiple first control curves is selected as the second control control curve.

5. The method for high-efficiency and energy-saving control of permanent magnet motor retrofitting of stirring according to any one of claims 1-4, characterized in that, The method further includes: The liquid level information of the stirring container is collected. When the liquid level rise in the stirring container reaches a preset value, the permanent magnet motor is controlled to return to the material static start-up stage and restart the stirring operation.

6. A SCADA system, characterized in that, include: Memory containing executable program code; A processor coupled to the memory; The processor calls the executable program code stored in the memory to execute the method for high-efficiency and energy-saving control of stirring by retrofitting a permanent magnet motor as described in any one of claims 1 to 5.

7. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program, wherein the computer program causes a computer to execute the method for high-efficiency and energy-saving control of stirring by retrofitting a permanent magnet motor as described in any one of claims 1 to 5.

8. A high-efficiency and energy-saving control system for retrofitting a stirring machine with a permanent magnet motor, characterized in that, It includes: The system comprises a SCADA system, a permanent magnet motor, a controller, and a hydrometer. The SCADA system is electrically connected to the permanent magnet motor via the controller. The hydrometer is installed in a mixing container; two or more hydrometers are installed in the mixing container used for material mixing. The hydrometers are distributed along the height of the mixing container. The output terminals of the hydrometers are electrically connected to the SCADA system. The SCADA system is used for: Based on the target density of the material and the characteristics of different stages, a control group running program curve is set for the output of the permanent magnet motor. The permanent magnet motor is controlled to run according to the control group running program curve. The density and specific gravity data of the material at different stages and depths during the stirring process are collected by the hydrometer. The density and specific gravity data are compared with the target density until the density and specific gravity data of the material at different depths all reach the target density. The rotational speed of the permanent magnet motor is adjusted at different stages of the running program curve of the control group to form a first control curve. The permanent magnet motor is controlled to run according to the first control curve to stir the material until the density and specific gravity data of the material at different depths all reach the target density. The energy consumption of stirring the material using the control group running program curve and the first control curve is obtained, and the one with the smaller energy consumption is selected as the second control control curve. Repeat the above adjustments multiple times until the optimal control curve is obtained; The different stages, arranged in the order of the permanent magnet motor's operation, are: the material static start-up stage, the material movement until uniform distribution stage, and the material uniformly distributed and suspended without settling stage. A control group operating program curve for the permanent magnet motor output is set based on the target density of the material and the characteristics of each stage, including: During the material static start-up phase, the permanent magnet motor outputs low speed and high torque to suspend most of the material. During the stage where the material moves until it is evenly distributed, the rotational speed of the permanent magnet motor is gradually increased while maintaining the frequency vibration, so that the material in the low-efficiency stirring zone can achieve a relative motion state through vibration. During the stage where the material is evenly distributed and kept suspended without settling, the permanent magnet motor maintains the minimum suspension speed, and then vibrates at preset intervals to increase the relative motion of the material.

9. The high-efficiency and energy-saving control system for retrofitting a stirring machine using a permanent magnet motor according to claim 8, characterized in that, The system also includes: a liquid level sensor, which is installed on the stirring container and is used to collect the liquid level position of the material and send the liquid level position information to the SCADA system; The SCADA system also automatically calculates the current volume and load ratio of the liquid in the stirring container based on changes in liquid level sensor data and changes in permanent magnet motor current and voltage data, and automatically adjusts the motor speed and operating curve to keep the motor speed at the optimal operating speed and the lowest suspension speed. The SCADA system is also used to control the permanent magnet motor to return to the material static start-up stage and restart the stirring operation when it detects an increase in the current of the permanent magnet motor or a rise in the liquid level, until the material is evenly distributed.

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