Motor dynamic driving control method, device and system based on motor working condition

Abstract

The invention relates to a motor dynamic driving control method, device and system based on motor working conditions. The motor dynamic driving control method based on the motor working condition comprises the following steps: S1, acquiring motor operation data; s2, judging the working condition of the motor according to the operation data of the motor; s3, selecting a corresponding control algorithm according to the working condition of the motor; and S4, through the control algorithm, according to the motor operation data, generating a control signal. The working condition of the motor is actively judged by monitoring the operation data of the motor, then the appropriate control algorithm is adaptively switched according to the current working condition of the motor, and high motor efficiency and good stability can be obtained under any working condition of the motor.

Description

Technical Field

[0001] The present invention relates to the field of motor technology, and in particular to a motor dynamic drive control method, device and system based on motor working conditions. Background Art

[0002] With the development of industrial automation and intelligent manufacturing, permanent magnet synchronous servo motors (PMSM) are widely used in various mechanical equipment due to their high efficiency, precision and reliability. Permanent magnet synchronous servo motors include stators and rotors. The stator consists of an iron core and a coil to generate a rotating magnetic field. The rotor consists of permanent magnets and bearings, and the permanent magnets are used to generate a constant magnetic field.

[0003] According to the principle that like poles repel each other and opposite poles attract each other, the magnetic poles of the stator rotating magnetic field and the rotor constant magnetic field will attract each other. Therefore, by controlling the current in the stator coil, the size and direction of the rotating magnetic field can be controlled, thereby driving the rotor to rotate together. The purpose of the motor drive control method is to generate a control signal to control the current in the stator coil of the permanent magnet synchronous servo motor, and then control the permanent magnet synchronous servo motor to complete the specified task.

[0004] However, existing motor drive control methods are usually based on the ideal operating condition of stable low load as a model. When the motor operating condition changes, they can only passively adapt and cannot actively make adaptive adjustments. The dynamic response capability is insufficient. Not only is the motor efficiency low under special motor conditions, but the stability is also poor under conditions of sudden changes in load. Summary of the invention

[0005] Based on this, an object of the present invention is to provide a motor dynamic drive control method, device and system based on motor operating conditions.

[0006] The present invention provides a motor dynamic drive control method based on motor operating conditions, comprising the steps of: S1, acquiring motor operating data; S2, judging the motor operating conditions according to the motor operating data; S3, selecting a corresponding control algorithm according to the motor operating conditions; S4, generating a control signal according to the motor operating data through the control algorithm.

[0007] The present invention actively determines the motor operating condition by monitoring the motor operation data, and then adaptively switches the appropriate control algorithm according to the current motor operating condition. Compared with the traditional PID control algorithm, higher motor efficiency and better stability can be achieved regardless of the operating condition of low speed and high load, high speed and low load, or sudden load change.

[0008] Further, in step S2, the motor operating conditions include: low speed and high load conditions, high speed and low load conditions and load sudden change conditions; in step S3, the control algorithm corresponding to the low speed and high load conditions is a fuzzy adaptive control algorithm, the control algorithm corresponding to the high speed and low load conditions is a PID control algorithm, and the control algorithm corresponding to the load sudden change conditions is an adaptive PID control algorithm.

[0009] Further, step S2 specifically includes: S21, when the motor operation data meets the high-speed and low-load operating condition, judging that the motor operating condition is a high-speed and low-load operating condition; the high-speed and low-load operating condition is specifically: the motor speed> the set first speed threshold, the motor torque< the set first torque threshold, and the motor stator current< the set first current threshold; S22, when the motor operation data meets the low-speed and high-load operating condition, judging that the motor operating condition is a low-speed and high-load operating condition; the low-speed and high-load operating condition is specifically: the motor speed< the set second speed threshold, the torque> the set second torque threshold, and the motor stator current> the set second current threshold.

[0010] Further, step S2 also includes: S23, when the motor operation data meets the load mutation operating condition, the motor operating condition is judged to be a load mutation operating condition; the load mutation operating condition is specifically: within a preset detection time period, the motor speed change rate> the set speed change rate threshold, the motor torque change rate> the set torque change rate threshold, the motor load change rate> the set load change rate threshold, the stator current change rate> the set stator current change rate threshold, or the motor efficiency change rate> the set motor efficiency change rate threshold; and / or, within a preset detection time period, the motor load change rate> the set load change rate threshold, and the load change duration> the set change time threshold.

[0011] Furthermore, the method further includes step S5 after step S4: repeating steps S1-S4, continuously monitoring the motor operating condition according to the motor operation data, and switching the corresponding control algorithm according to the motor operating condition.

[0012] Further, step S3 specifically includes: S31, determining whether the motor operating condition has changed; S32, if the motor operating condition has changed, switching the control algorithm to a control algorithm corresponding to the current motor operating condition; S33, if the motor operating condition has not changed, maintaining the current control algorithm unchanged.

[0013] Furthermore, the method also includes the steps of: before switching the control algorithm in step S32, using a data buffer to save the motor operation data; after switching the control algorithm in step S32, using the motor operation data saved in the data buffer as the input condition of the new control algorithm, maintaining the preset buffer time, and then allowing the new control algorithm to generate a control signal according to the current motor operation data.

[0014] Further, step S32 switches the control algorithm to the control algorithm corresponding to the current motor working condition, and step S4 generates a control signal through the control algorithm, specifically: within the preset buffer time, a first control signal is generated by the original control algorithm before switching, and a second control signal is generated by the new control algorithm after switching; the first control signal and the second control signal are weighted and superimposed to obtain the final output control signal; after the preset buffer time ends, a control signal is generated by the new control algorithm after switching; wherein, within the preset buffer time, the calculation formula of the control signal is: S=α1·S1+α2·S2, wherein S represents the final output control signal, S1 represents the first control signal, S2 represents the second control signal, α1 represents the weight corresponding to the first control signal, and α2 represents the weight corresponding to the second control signal; the calculation formula of the weight α1 corresponding to the first control signal is: Wherein T represents the length of the preset buffer time, t represents the current time starting from the instant of switching the control algorithm; the calculation formula of the weight α2 corresponding to the second control signal is: Wherein T represents the length of the preset buffer time, and t represents the current time starting from the instant of switching the control algorithm.

[0015] Based on the same inventive concept, the present invention also provides a motor dynamic drive control device based on motor operating conditions, including: a motor operation data acquisition module, which is used to acquire motor operation data; a motor operating condition judgment module, which is used to judge the motor operating condition according to the motor operation data; a control algorithm switching module, which is used to select a corresponding control algorithm according to the motor operating condition; and a control signal generation module, which generates a control signal according to the motor operation data through the control algorithm.

[0016] Based on the same inventive concept, the present invention also provides a motor dynamic drive system based on motor working conditions, including: a sensor module, a control device and a drive module; the sensor module monitors the motor body to collect motor operation data; the control device executes any of the above-mentioned motor dynamic drive control methods based on motor working conditions to generate a dynamically adjusted control signal according to the motor operation data; the drive module controls the drive current at the input end of the motor body according to the control signal, thereby dynamically controlling the operation of the motor body.

[0017] For better understanding and implementation, the present invention is described in detail below with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a module schematic diagram of the motor dynamic drive system based on the motor working condition of the present invention;

[0019] Figure 2 It is a module schematic diagram of the motor dynamic drive control device based on the motor working condition of the present invention;

[0020] Figure 3 It is a flow chart of the motor dynamic drive control method based on the motor working condition of the present invention. DETAILED DESCRIPTION

[0021] It should be clear that the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the embodiments of the present application.

[0022] The terms used in the embodiments of the present application are only for the purpose of describing specific embodiments, and are not intended to limit the embodiments of the present application. The singular forms of "a", "said" and "the" used in the embodiments of the present application and the appended claims are also intended to include plural forms, unless the context clearly indicates other meanings.

[0023] When the following description refers to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present application. On the contrary, they are merely examples of devices and methods consistent with some aspects of the present application as detailed in the attached claims. In the description of the present application, it should be understood that the terms "first", "second", "third", etc. are only used to distinguish similar objects, and do not have to be used to describe a specific order or sequence, nor can they be understood as indicating or implying relative importance. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to the specific circumstances.

[0024] In addition, in the description of this application, unless otherwise specified, "plurality" means two or more. "And / or" describes the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone. The character " / " generally indicates that the associated objects are in an "or" relationship.

[0025] It should be understood that the embodiments of the present application are not limited to the precise structures described above and shown in the drawings, and various modifications and changes can be made without departing from the scope thereof. The scope of the embodiments of the present application is limited only by the appended claims.

[0026] When the motor power is constant, the higher the load of the motor, the lower its speed. In the process of starting and stopping, the preset rated power of the motor generally does not change. Therefore, the motor working conditions can be divided into low-speed and high-load conditions, high-speed and low-load conditions, and sudden load changes according to the speed and load.

[0027] The existing motor drive control method is generally a PID control algorithm, which performs poorly under low-speed and high-load conditions and load mutation conditions. For example, under low-speed and high-load conditions, due to the low speed of the motor, the induced voltage of the motor is small, so the energy loss is large and the overall efficiency of the motor is low. The existing motor drive method is difficult to ensure the working efficiency of the motor under low-speed and high-load conditions, and the energy efficiency is relatively low. Under load mutation conditions, the PID control algorithm cannot adjust the motor speed in time, not only the dynamic response is slow, but also overshoot is prone to occur, affecting production efficiency and equipment stability.

[0028] The present invention actively determines the motor working condition by monitoring the motor operation data, and then adaptively switches the appropriate control algorithm according to the current motor working condition, so that higher motor efficiency can be achieved regardless of the low-speed and high-load working condition, the high-speed and low-load working condition, or the load sudden change working condition. The present invention designs a buffer mechanism for the instability phenomenon at the moment of control algorithm switching, taking into account both motor efficiency and stability.

[0029] See also Figure 1 , Figure 1 It is a module schematic diagram of the motor dynamic drive system based on the motor working condition of the present invention. The motor dynamic drive system based on the motor working condition of the present invention comprises: a sensor module 1, a control device 2 and a drive module 3. The sensor module 1 monitors the motor body to collect motor operation data. The control device 2 is the motor dynamic drive control device based on the motor working condition of the present invention, which generates a dynamically adjusted control signal according to the motor operation data by executing the motor dynamic drive control method based on the motor working condition of the present invention. The drive module 3 controls the drive current at the input end of the motor body according to the control signal, and then dynamically controls the operation of the motor body. Specifically, the drive module 3 can be an inverter, which controls the operation of the motor body by controlling the size and frequency of the drive current at the input end of the motor body.

[0030] See also Figure 2 and Figure 3 , Figure 2is a module schematic diagram of a motor dynamic drive control device based on motor working conditions of the present invention, Figure 3 It is a flow chart of the motor dynamic drive control method based on the motor working condition of the present invention.

[0031] Specifically, the control device 2 includes: an initialization module M0, a motor operation data acquisition module M1, a motor operating condition judgment module M2, a control algorithm switching module M3, a control signal generation module M4 and a circulation module M5.

[0032] The initialization module M0 is used to execute step S0: regard the default working condition as the initial motor working condition, use the control algorithm corresponding to the default working condition as the initial control algorithm, and generate a control signal according to the initial control algorithm. The motor working condition includes a low-speed high-load working condition, a high-speed low-load working condition, and a load mutation working condition. In this embodiment, the default working condition is set to a high-speed low-load working condition, and the corresponding initial control algorithm is a PID control algorithm.

[0033] The motor operation data acquisition module M1 is used to execute step S1: acquiring the motor operation data collected by the sensor module 1. The motor operation data includes: the motor speed, torque, stator current, input terminal voltage and output terminal voltage. In one embodiment, the motor operation data also includes load.

[0034] The motor operating condition determination module M2 is used to execute step S2: determine the motor operating condition according to the motor operation data.

[0035] Wherein, step S2 comprises:

[0036] S21, when the motor operation data meets the high-speed and low-load working condition, the motor working condition is judged to be a high-speed and low-load working condition. The high-speed and low-load working condition is specifically: the motor speed> the set first speed threshold, the motor torque< the set first torque threshold, and the motor stator current< the set first current threshold. In this embodiment, the first speed threshold is set to 2000rpm; the first torque threshold is set to 20% of the rated torque, and the first current threshold is set to 30% of the rated current.

[0037] S22, when the motor operation data meets the low-speed and high-load working condition, the motor working condition is judged to be a low-speed and high-load working condition. The low-speed and high-load working condition is specifically: the motor speed < the set second speed threshold, the torque > the set second torque threshold, and the motor stator current > the set second current threshold. In this embodiment, the second speed threshold is set to 1000rpm; the second torque threshold is set to 80% of the rated torque; and the second current threshold is set to 90% of the rated current.

[0038] S23, when the motor operation data meets the load mutation condition, determining that the motor operation condition is a load mutation condition.

[0039] In the embodiment where the motor operation data does not include the load, the load mutation operating condition is specifically: within the preset detection time period, the motor speed change rate> the set speed change rate threshold, the motor torque change rate> the set torque change rate threshold, the motor load change rate> the set load change rate threshold, the stator current change rate> the set stator current change rate threshold, or the motor efficiency change rate> the set motor efficiency change rate threshold. In this embodiment, the torque change rate threshold is set to 30% / 5ms of the rated torque.

[0040] The output power and input power of the motor can be calculated through the stator current, input voltage and output voltage. Since the motor efficiency is equal to the ratio of the motor output power to the input power, the motor efficiency can be obtained by calculating the motor output power and input power.

[0041] In an embodiment where the motor operation data includes load, the load mutation operating condition is specifically: within a preset detection time period, the motor load change rate> the set load change rate threshold, and the load change duration> the set change time threshold. In one embodiment, the load change rate threshold is set to 50% / 1s, and the change time threshold is set to 100ms.

[0042] S24, when the motor operation data does not satisfy any of the above operating conditions, it is determined that the motor operating condition has not changed, that is, it is determined that the motor operating condition is the motor operating condition at the last moment.

[0043] The control algorithm switching module M3 is used to execute step S3: select a corresponding control algorithm according to the motor working condition. Step S3 specifically includes: S31, judging whether the motor working condition has changed. S32, if the motor working condition has changed, switching the control algorithm to the control algorithm corresponding to the current motor working condition. S33, if the motor working condition has not changed, maintaining the current control algorithm unchanged.

[0044] In this embodiment, the control algorithm corresponding to the low speed and high load condition is a fuzzy adaptive control algorithm, the control algorithm corresponding to the high speed and low load condition is a PID control algorithm, and the control algorithm corresponding to the load sudden change condition is an adaptive PID control algorithm.

[0045] The control signal generating module M4 is used to execute step S4: generating a control signal according to the motor operation data through the control algorithm.

[0046] The loop module M5 is used to execute step S5: repeatedly call the motor operation data acquisition module M1, the motor operating condition judgment module M2, the control algorithm switching module M3 and the control signal generation module M4, repeatedly execute steps S1-S4, continuously monitor the motor operating condition according to the motor operation data, and switch the corresponding control algorithm according to the motor operating condition.

[0047] Furthermore, the inventors discovered that the problem of control signal overshoot or oscillation may occur at the moment of switching the control algorithm in step S32. This may be due to the different initial conditions of different control algorithms, and the input parameters cannot be continuously transmitted when switching the control algorithm; or the hardware computing power of the control device is limited, resulting in a decrease in the response speed at the moment of switching the algorithm. To this end, the control method of the present invention also includes the steps of: before switching the control algorithm in step S32, using a data buffer to save the motor operation data; after switching the control algorithm in step S32, using the motor operation data saved in the data buffer as the input condition of the new control algorithm, maintaining the preset buffer time, and then allowing the new control algorithm to generate a control signal according to the current motor operation data.

[0048] Further, step S32 switches the control algorithm to the control algorithm corresponding to the current motor operating condition, and step S4 generates a control signal through the control algorithm, specifically: within a preset buffer time, a first control signal is generated by the original control algorithm before switching, and a second control signal is generated by the new control algorithm after switching; the first control signal and the second control signal are weightedly superimposed to obtain a final output control signal; after the preset buffer time ends, a control signal is generated by the new control algorithm after switching.

[0049] Among them, within the preset buffer time, the calculation formula of the control signal is: S = α1·S1+α2·S2, where S represents the final output control signal, S1 represents the first control signal, S2 represents the second control signal, α1 represents the weight corresponding to the first control signal, and α2 represents the weight corresponding to the second control signal. The weight α1 corresponding to the first control signal and the weight α2 corresponding to the second control signal satisfy the following relationship: α1+α2=1, and α1 decreases with time, and α2 increases with time. In this embodiment, the calculation formula of the weight α1 corresponding to the first control signal is: Where T represents the length of the preset buffer time, and t represents the current time starting from the instant of switching the control algorithm. The calculation formula of the weight α2 corresponding to the second control signal is: Wherein T represents the length of the preset buffer time, and t represents the current time starting from the instant of switching the control algorithm.

[0050] Furthermore, in order to ensure that the control device has sufficient computing performance, the control device 2 is a high-performance DSP or FPGA with parallel processing capabilities.

[0051] The technical effect of the present invention is explained below in combination with experimental data. This experiment uses a permanent magnet synchronous servo motor with a rated power of 5kW and a rated speed of 3000rpm as the motor body to be controlled, and a simple PID control algorithm is used as the traditional scheme control group. This experiment uses the traditional scheme and the motor dynamic drive control method of the present invention to control the motor body, and measures the motor performance by detecting the motor efficiency of the motor body. The experimental conditions and experimental results are shown in the following table:

[0052] Table 1: Constant load conditions

[0053] Working conditions Speed ​​(rpm) Loading capacity (%) Motor efficiency of the present invention (%) Traditional solution motor efficiency (%) Low speed and high load conditions 500 80 83.2 72.9 High speed and low load conditions 2500 5 89.6 83.8

[0054] Table 2: Load mutation conditions

[0055]

[0056] The load (%) in the table refers to the percentage of the load relative to the rated maximum load; the motor efficiency (%) refers to the ratio of the motor's output power to its input power. It can be seen from the above experimental data that the motor dynamic drive control method of the present invention can achieve higher motor efficiency than the traditional PID control algorithm, regardless of whether it is under low-speed and high-load conditions, high-speed and low-load conditions, or load mutation conditions. Furthermore. The present invention also designs a buffer mechanism for the unstable phenomenon at the moment of switching the control algorithm, taking into account both motor efficiency and stability.

[0057] The above-mentioned embodiments only express several implementation methods of the present invention, and the description is relatively specific and detailed, but it cannot be understood as limiting the scope of the invention patent. It should be pointed out that for ordinary technicians in this field, several modifications and improvements can be made without departing from the concept of the present invention, and the present invention is also intended to include these modifications and modifications.

Claims

1. A motor dynamic drive control method based on motor working conditions, characterized in that: Includes steps: S1, obtain motor operation data; S2, judging the motor operating condition according to the motor operating data; S3, selecting a corresponding control algorithm according to the motor operating condition; S4, generating a control signal according to the motor operation data through the control algorithm.

2. The motor dynamic drive control method based on motor working conditions according to claim 1, characterized in that: In step S2, the motor operating conditions include: low speed and high load operating conditions, high speed and low load operating conditions, and load sudden change operating conditions; In step S3, the control algorithm corresponding to the low-speed and high-load working condition is a fuzzy adaptive control algorithm, the control algorithm corresponding to the high-speed and low-load working condition is a PID control algorithm, and the control algorithm corresponding to the load sudden change working condition is an adaptive PID control algorithm.

3. The motor dynamic drive control method based on motor working condition according to claim 2 is characterized in that: Step S2 specifically includes: S21, when the motor operation data meets the high-speed and low-load working condition, determining that the motor working condition is a high-speed and low-load working condition; the high-speed and low-load working condition is specifically: the motor speed> the set first speed threshold, the motor torque< the set first torque threshold, and the motor stator current< the set first current threshold; S22, when the motor operation data meets the low-speed and high-load operating condition, the motor operating condition is judged to be a low-speed and high-load operating condition; the low-speed and high-load operating condition is specifically: the motor speed < the set second speed threshold, the torque > the set second torque threshold, and the motor stator current > the set second current threshold.

4. The motor dynamic drive control method based on motor working conditions according to claim 3 is characterized in that: Step S2 further includes: S23, when the motor operation data meets the load mutation condition, determining that the motor operation condition is a load mutation condition; The load mutation operating condition is specifically: Within a preset detection time period, the rate of change of the motor speed is greater than a set speed change rate threshold, the rate of change of the motor torque is greater than a set torque change rate threshold, the rate of change of the motor load is greater than a set load change rate threshold, the rate of change of the stator current is greater than a set stator current change rate threshold, or the rate of change of the motor efficiency is greater than a set motor efficiency change rate threshold; and / or, During a preset detection time period, the motor load change rate is greater than a set load change rate threshold, and the load change duration is greater than a set change time threshold.

5. The motor dynamic drive control method based on motor working conditions according to claim 1, characterized in that: The method further includes a step S5 after the step S4: repeating the steps S1-S4, continuously monitoring the motor operating condition according to the motor operating data, and switching the corresponding control algorithm according to the motor operating condition.

6. The motor dynamic drive control method based on motor working conditions according to claim 5 is characterized in that: Step S3 specifically includes: S31, determining whether the motor operating condition has changed; S32, if the motor operating condition has changed, switching the control algorithm to the control algorithm corresponding to the current motor operating condition; S33, if the motor operating condition has not changed, maintaining the current control algorithm unchanged.

7. The motor dynamic drive control method based on motor working conditions according to claim 6 is characterized in that: The method also includes the following steps: before switching the control algorithm in step S32, using a data buffer to save the motor operation data; after switching the control algorithm in step S32, using the motor operation data saved in the data buffer as the input condition of the new control algorithm, maintaining the preset buffer time, and then allowing the new control algorithm to generate a control signal according to the current motor operation data.

8. The motor dynamic drive control method based on motor working conditions according to claim 6, characterized in that: Step S32 switches the control algorithm to the control algorithm corresponding to the current motor working condition, and step S4 generates a control signal through the control algorithm, specifically: within a preset buffer time, a first control signal is generated through the original control algorithm before switching, and a second control signal is generated through the new control algorithm after switching; the first control signal and the second control signal are weightedly superimposed to obtain a final output control signal; after the preset buffer time ends, a control signal is generated through the new control algorithm after switching; Wherein, within the preset buffer time, the calculation formula of the control signal is: S=α1·S1+α2·S2, where S represents the final output control signal, S1 represents the first control signal, S2 represents the second control signal, α1 represents the weight corresponding to the first control signal, and α2 represents the weight corresponding to the second control signal; The calculation formula of the weight α1 corresponding to the first control signal is: Wherein T represents the length of the preset buffer time, t represents the current time starting from the instant of switching the control algorithm; the calculation formula of the weight α2 corresponding to the second control signal is: Wherein T represents the length of the preset buffer time, and t represents the current time starting from the instant of switching the control algorithm.

9. A motor dynamic drive control device based on motor working conditions, characterized in that: include: A motor operation data acquisition module, which is used to acquire motor operation data; A motor operating condition judgment module, which is used to judge the motor operating condition according to the motor operation data; A control algorithm switching module, which is used to select a corresponding control algorithm according to the motor working condition; A control signal generating module generates a control signal according to the motor operation data through the control algorithm.

10. A motor dynamic drive system based on motor working conditions, characterized in that: include: Sensor module, control device and drive module; The sensor module monitors the motor body to collect motor operation data; The control device executes the motor dynamic drive control method based on the motor working condition according to any one of claims 1 to 8 to generate a dynamically adjusted control signal according to the motor operation data; The driving module controls the driving current at the input end of the motor body according to the control signal, thereby dynamically controlling the operation of the motor body.

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