Drive method, system and related components for large inertia flexible load drive systems

Abstract

The application discloses a driving method and system of a large-inertia flexible load transmission system and related components, and relates to the field of load transmission systems. In the large-inertia flexible load transmission system, the output end of a motor is connected to a load. The driving method comprises the following steps: obtaining a load torque current; performing low-frequency filtering on the load torque current to obtain a filtered current; obtaining an adjusted current according to the load torque current and the filtered current; inputting the adjusted current into a first PI controller to obtain an adjusted frequency; determining a final given frequency according to the adjusted frequency and a preliminary given frequency; and performing speed loop control on the motor by taking the final given frequency as a motor given frequency. When the final given frequency is used to perform speed loop control on the motor, low-frequency oscillation caused by the characteristics of the flexible load can be inhibited. The method does not require a sensor and does not need to modify parameters specifically, and has the advantages of low cost and high applicability.

Description

Technical Field

[0001] This invention relates to the field of load transmission systems, and in particular to a driving method, system, and related components for a large inertia flexible load transmission system. Background Technology

[0002] High-inertia flexible loads are widely found in various production fields. The high inertia and flexibility of these loads are mainly manifested in low-frequency oscillations, which can not only affect speed control accuracy but also damage machinery and cause industrial accidents. Therefore, it is crucial to develop a simple and feasible vibration suppression method for high-inertia flexible transmission systems.

[0003] In existing technologies, to suppress vibration, a position or velocity sensor is typically installed at the flexible load end to form a dual closed-loop control between the motor end and the load end, thereby suppressing the vibration of the flexible load. However, adding a sensor increases the system cost, and some loads operate in harsh environments where the sensor is affected by the external environment, causing transmission errors in the sensing signal, which in turn exacerbates the vibration of the system and affects its safe operation.

[0004] Due to the limitations of sensors, some researchers have proposed inserting a notch filter between the output of the motor vector control speed loop and the given torque current to achieve smooth driving of flexible loads. Others have proposed calculating the dynamic model of the flexible load, extracting its characteristic parameters, and combining this with a shaper to achieve smooth driving. Both of these methods require modifying the parameters of the notch filter or shaper using the characteristic parameters of the flexible load. Since the characteristic parameters of the load vary depending on the application, these two methods have poor adaptability and are not suitable for practical engineering applications.

[0005] Therefore, how to provide a solution to the above-mentioned technical problems is a problem that needs to be solved by those skilled in the art. Summary of the Invention

[0006] In view of this, the purpose of this invention is to provide a driving method, system, and related components for a large inertia flexible load transmission system with higher applicability. The specific solution is as follows:

[0007] A driving method for a high-inertia flexible load transmission system, wherein the output terminal of a motor in the high-inertia flexible load transmission system is connected to a load, and the driving method includes:

[0008] Obtain the load torque current;

[0009] The load torque current is filtered at a low frequency to obtain the filtered current.

[0010] The regulating current is obtained based on the load torque current and the filtered current;

[0011] The regulating current is input into the first PI controller to obtain the regulating frequency;

[0012] Based on the adjusted frequency and the initial given frequency, determine the final given frequency;

[0013] The final given frequency is used as the motor's given frequency for speed loop control of the motor.

[0014] Preferably, the process of obtaining the regulating current based on the load torque current and the filtered current includes:

[0015] The load torque current is subtracted from the filtered current to obtain the regulating current;

[0016] Accordingly, the process of determining the final given frequency based on the adjusted frequency and the initially given frequency includes:

[0017] The final given frequency is determined by summing the adjusted frequency and the initially given frequency.

[0018] Preferably, the process of performing low-frequency filtering on the load torque current to obtain the filtered current includes:

[0019] The load torque current and the actual frequency of the motor are input into the observer module to obtain the observed current;

[0020] The observed current is subjected to low-frequency filtering to obtain the filtered current.

[0021] Preferably, after using the final given frequency as the motor's given frequency to perform speed loop control on the motor, the method further includes:

[0022] The observed current is used as the feedforward current for the current loop control.

[0023] Accordingly, this application also discloses a drive system for a large inertia flexible load transmission system, wherein the output end of the motor in the large inertia flexible load transmission system is connected to the load, and the drive system includes:

[0024] The acquisition module is used to acquire the load torque current;

[0025] The filtering module is used to perform low-frequency filtering on the load torque current to obtain the filtered current.

[0026] The first adjustment module is used to obtain the adjustment current based on the load torque current and the filtered current;

[0027] The second adjustment module is used to input the adjustment current into the first PI controller to obtain the adjustment frequency;

[0028] The third adjustment module is used to determine the final given frequency based on the adjustment frequency and the initial given frequency;

[0029] The control module is used to perform speed loop control on the motor by using the final given frequency as the motor's given frequency.

[0030] Preferably, the first adjustment module is specifically used for:

[0031] The load torque current is subtracted from the filtered current to obtain the regulating current;

[0032] Accordingly, the third adjustment module is specifically used for:

[0033] The final given frequency is determined by summing the adjusted frequency and the initially given frequency.

[0034] Preferably, the filtering module includes:

[0035] The observation unit is used to input the load torque current and the actual frequency of the motor into the observer module to obtain the observed current;

[0036] A filtering unit is used to perform low-frequency filtering on the observed current to obtain the filtered current.

[0037] Preferably, after the control module uses the final given frequency as the motor's given frequency to perform speed loop control on the motor, it is further used to:

[0038] The observed current is used as the feedforward current for the current loop control.

[0039] Accordingly, this application also discloses an electronic device, including:

[0040] Memory, used to store computer programs;

[0041] A processor, configured to execute the computer program to implement the steps of a driving method for a large inertia flexible load transmission system as described in any of the preceding descriptions.

[0042] Accordingly, this application also discloses a readable storage medium storing a computer program, which, when executed by a processor, implements the steps of a driving method for a large inertia flexible load transmission system as described in any of the above claims.

[0043] This application discloses a driving method for a large-inertia flexible load transmission system. In the system, the output terminal of a motor is connected to a load. The driving method includes: acquiring the load torque current; performing low-frequency filtering on the load torque current to obtain a filtered current; obtaining an adjustment current based on the load torque current and the filtered current; inputting the adjustment current into a first PI controller to obtain an adjustment frequency; determining a final set frequency based on the adjustment frequency and a preliminary set frequency; and using the final set frequency as the motor set frequency for speed loop control of the motor. This application obtains an adjustment frequency related to the flexible load characteristics by processing the load torque current containing flexible load characteristics, and determines the final set frequency using the adjustment frequency and the preliminary set frequency. This allows for the suppression of low-frequency oscillations generated by the flexible load characteristics when using the final set frequency for motor speed loop control. This method does not require sensors or specific parameter modifications, offering advantages such as low cost and high applicability. Attached Figure Description

[0044] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0045] Figure 1 This is a flowchart illustrating the steps of a driving method for a large inertia flexible load transmission system according to an embodiment of the present invention.

[0046] Figure 2 This is a block diagram of a motor control interface according to an embodiment of the present invention;

[0047] Figure 3 This is a block diagram of the control interface of another motor in an embodiment of the present invention;

[0048] Figure 4 This is a block diagram of the control interface of an observer in an embodiment of the present invention;

[0049] Figure 5 The image shows the simulation results of the rotational speed without using the driving method of this embodiment;

[0050] Figure 6 The image shows the simulation results of the rotational speed using the driving method of this embodiment.

[0051] Figure 7 This is a structural distribution diagram of the drive system of a large inertia flexible load transmission system according to 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] Currently, methods used to suppress oscillations in flexible transmission systems include adding sensors at the load end, inserting a notch filter after the speed loop output, and designing dynamic models. These methods are costly in terms of components or design, and their effectiveness in practical applications is not ideal.

[0054] This application obtains an adjustment frequency related to the flexible load characteristics by processing the load torque current containing flexible load characteristics, and then determines the final set frequency using the adjustment frequency and the initial set frequency. This allows for the suppression of low-frequency oscillations generated by the flexible load characteristics when using the final set frequency for motor speed loop control. This method requires no sensors or specific parameter modifications, offering advantages such as low cost and high applicability.

[0055] This invention discloses a driving method for a large inertia flexible load transmission system, wherein the output terminal of the motor in the large inertia flexible load transmission system is connected to the load. (See also...) Figure 1 As shown, the driving method includes:

[0056] S1: Obtain the load torque current;

[0057] S2: Perform low-frequency filtering on the load torque current to obtain the filtered current;

[0058] S3: Obtain the regulating current based on the load torque current and the filtered current;

[0059] S4: Input the regulating current into the first PI controller to obtain the regulating frequency;

[0060] S5: Determine the final set frequency based on the adjusted frequency and the initial set frequency;

[0061] S6: Use the final given frequency as the motor's given frequency to perform speed loop control on the motor.

[0062] Step S3, based on the load torque current and the filtered current, involves obtaining the adjustment current, including:

[0063] The load torque current is subtracted from the filtered current to obtain the regulating current;

[0064] Accordingly, step S5, which determines the final given frequency based on the adjusted frequency and the initial given frequency, includes:

[0065] The final given frequency is determined by summing the adjusted frequency and the initial given frequency.

[0066] Understandably, in a high-inertia flexible load drive system, the motor's output terminal is connected to the high-inertia flexible load, so the motor's current can reflect the load's characteristics. Typically, the motor's real-time current i... sa i sb and i sc Perform coordinate transformation to obtain the real-time q-axis current i q and d-axis real-time current i d The real-time q-axis current i q This is the load torque current in this embodiment.

[0067] See Figure 2 The block diagram shown illustrates that conventional dual-loop control of a motor includes an outer speed loop and an inner current loop. In this embodiment, the driving method is represented by the dashed box, where the load torque current is specifically the q-axis real-time current i. q , the load torque current i q The input is fed into a low-frequency filter to obtain the filtered current i. q_flt The specific filtering relationship is as follows: Where ω c The filter bandwidth of the low-frequency filter is calculated by subtracting the load torque current from the filtered current to obtain the regulating current. This regulating current is then input to the first PI controller for PI regulation, yielding the regulating frequency f**. The specific relationship is as follows: Where K p and K i These are the two adjustment coefficients of the first PI controller; the adjustment frequency f** and the initial set frequency f* are added together, and the sum is taken as the final set frequency f. final Then the final given frequency f final As the given frequency input to the motor, the speed loop control further participates in the subsequent motor control.

[0068] The specific speed loop control includes: the final set frequency f final Subtracting the actual frequency f of the motor, the difference is input to the second PI controller to obtain the q-axis regulating current i. q ** Simultaneously set the d-axis adjustable current i d ** The current i is 0, and the current is adjusted by the q-axis. q ** and d-axis adjustment current i d ** Perform speed loop control;

[0069] Speed ​​loop control includes: q-axis current adjustment iq ** and d-axis adjustment current i d ** Relative to the real-time q-axis current i q and d-axis real-time current i d Subtracting the two values ​​yields two differences, which are then input into two third PI controllers for PI regulation, resulting in the q-axis regulating voltage u. q ** and d-axis adjustable voltage u d ** Then, adjust the q-axis voltage u based on the real-time potential angle θ. q ** and d-axis adjustable voltage u d ** Converted to regulating current u * and adjusting the potential angle θ v Based on the two, SVPWM conversion is performed to obtain the corresponding switching control signal input to the three-phase PWM inverter circuit.

[0070] Understandably, the output of the three-phase PWM inverter circuit drives the PMSM (Permanent Magnet Synchronous Motor), and the motor output is connected to the load. This application utilizes the load torque current to regulate the final set frequency f input to the motor speed loop. final This achieves oscillation suppression in a large-inertia flexible load transmission system.

[0071] This application discloses a driving method for a large-inertia flexible load transmission system. In the system, the output terminal of a motor is connected to a load. The driving method includes: acquiring the load torque current; performing low-frequency filtering on the load torque current to obtain a filtered current; obtaining an adjustment current based on the load torque current and the filtered current; inputting the adjustment current into a first PI controller to obtain an adjustment frequency; determining a final set frequency based on the adjustment frequency and a preliminary set frequency; and using the final set frequency as the motor set frequency for speed loop control of the motor. This application obtains an adjustment frequency related to the flexible load characteristics by processing the load torque current containing flexible load characteristics, and determines the final set frequency using the adjustment frequency and the preliminary set frequency. This allows for the suppression of low-frequency oscillations generated by the flexible load characteristics when using the final set frequency for motor speed loop control. This method does not require sensors or specific parameter modifications, offering advantages such as low cost and high applicability.

[0072] This invention discloses a specific driving method for a large inertia flexible load transmission system. Compared with the previous embodiment, this embodiment further explains and optimizes the technical solution. Specifically:

[0073] The process of performing low-frequency filtering on the load torque current to obtain the filtered current includes:

[0074] The load torque current and the actual frequency of the motor are input into the observer module to obtain the observed current;

[0075] The observed current is subjected to low-frequency filtering to obtain the filtered current.

[0076] Furthermore, after performing speed loop control on the motor using the final given frequency, the method further includes:

[0077] The observed current is used as the feedforward current for the current loop control.

[0078] See Figure 3 The control structure block diagram shows that the observer module can observe the load torque of the permanent magnet synchronous motor in real time and use the observed load torque as the feedforward of the current loop control algorithm, which effectively improves the dynamic performance of the permanent magnet synchronous motor and enhances the anti-interference capability of the system.

[0079] Specifically, the observer module performs the following actions:

[0080] The load torque current i q With torque coefficient K t Multiply to obtain the motor output torque T. e Multiplying the actual frequency f by 2π gives the rotor's mechanical angular velocity ω. m Then the motor output torque T e and rotor mechanical angular velocity ω m Input the observer to obtain the observed load torque. Further based on The observed current can then be obtained. Reusing the observed current Set the feedforward parameters for speed loop control and current loop control.

[0081] Understandably, according to the principles of electrical machinery, the equation of motion for an electric motor is:

[0082] J(dω m / dt)+B m ω m +T L =T e ;

[0083] In the formula: ω m T is the rotor's mechanical angular velocity. e T is the output torque of the motor. L Where J is the load torque, and B is the moment of inertia. m is the viscous damping coefficient.

[0084] From the above equation, its dynamic equation is obtained as follows:

[0085]

[0086] In the formula C = [1 0], u = T e y=ω m .

[0087] The dynamic equation can be further written as:

[0088]

[0089] Therefore, a simple dimension-reduced observer can be constructed, as shown in the following expression:

[0090]

[0091] In the formula: Let K be the state variable being estimated; K = [k1 k2] T The state feedback gain matrix;

[0092] Furthermore, we can obtain:

[0093]

[0094] In the formula The characteristic equation for observation error is:

[0095] det[sI-(A-KC)]=s 2 +(k1+B m / J)s-k2 / J=0;

[0096] Choose an appropriate K such that (A-KC) has stable and suitable eigenvalues. Based on the specified desired poles α and β, the desired characteristic polynomial of the observer is:

[0097] s 2 -(α+β)s-αβ=0;

[0098] From the characteristic equation and the expected characteristic polynomial, we can obtain:

[0099]

[0100] Assume B m If α = 0 and α = β, then the above equation can be rewritten as:

[0101]

[0102] The dimension reduction observer can be rewritten as:

[0103]

[0104] This dimension reduction observer can be used as the observer module in this embodiment; its internal structure is described in [reference needed]. Figure 4 The structural block diagram shown.

[0105] Furthermore, simulations were performed on large-inertia flexible load transmission systems for comparison. Figure 5 and Figure 6 ,in Figure 5 The simulation results are for the rotational speed when the driving method of this embodiment is not used. Figure 6 The simulation results of the rotational speed when using the driving method of this embodiment clearly show that this embodiment has a good suppression effect on flexible load characteristics and low-frequency vibration.

[0106] Accordingly, this application also discloses a drive system for a large inertia flexible load transmission system, wherein the output end of the motor in the large inertia flexible load transmission system is connected to the load, see [link to relevant documentation]. Figure 7 As shown, the drive system includes:

[0107] Module 1 is used to acquire the load torque current;

[0108] Filter module 2 is used to perform low-frequency filtering on the load torque current to obtain the filtered current;

[0109] The first adjustment module 3 is used to obtain the adjustment current based on the load torque current and the filtered current;

[0110] The second adjustment module 4 is used to input the adjustment current into the first PI controller to obtain the adjustment frequency;

[0111] The third adjustment module 5 is used to determine the final given frequency based on the adjustment frequency and the initial given frequency;

[0112] Control module 6 is used to perform speed loop control on the motor by using the final given frequency as the motor's given frequency.

[0113] This application embodiment obtains an adjustment frequency related to the flexible load characteristics by processing the load torque current containing flexible load characteristics, and determines the final set frequency using the adjustment frequency and the initial set frequency. This allows for the suppression of low-frequency oscillations generated by the flexible load characteristics when using the final set frequency for motor speed loop control. This drive system requires no sensors and no specific parameter modifications, offering advantages such as low cost and high applicability.

[0114] In some specific embodiments, the first adjustment module 3 is specifically used for:

[0115] The load torque current is subtracted from the filtered current to obtain the regulating current;

[0116] Accordingly, the third adjustment module 5 is specifically used for:

[0117] The final given frequency is determined by summing the adjusted frequency and the initially given frequency.

[0118] In some specific embodiments, the filtering module 2 includes:

[0119] The observation unit is used to input the load torque current and the actual frequency of the motor into the observer module to obtain the observed current;

[0120] A filtering unit is used to perform low-frequency filtering on the observed current to obtain the filtered current.

[0121] In some specific embodiments, after the control module 6 uses the final given frequency as the motor's given frequency to perform speed loop control on the motor, it is further used to:

[0122] The observed current is used as the feedforward current for the current loop control.

[0123] Accordingly, this application also discloses an electronic device, including:

[0124] Memory, used to store computer programs;

[0125] A processor, configured to execute the computer program to implement the steps of a driving method for a large inertia flexible load transmission system as described in any of the preceding descriptions.

[0126] Accordingly, this application also discloses a readable storage medium storing a computer program, which, when executed by a processor, implements the steps of a driving method for a large inertia flexible load transmission system as described in any of the above claims.

[0127] For a detailed description of the driving method of the large inertia flexible load transmission system, please refer to the relevant content in the above embodiments, which will not be repeated here.

[0128] In this embodiment, the electronic device and the readable storage medium have the same technical effects as the driving method of a large inertia flexible load transmission system described in the previous embodiment, and will not be repeated here.

[0129] Finally, it should be noted that in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0130] The above provides a detailed description of the driving method, system, and related components of a large inertia flexible load transmission system provided by 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 driving method for a large inertia flexible load transmission system, wherein the output terminal of a motor in the large inertia flexible load transmission system is connected to a load, characterized in that... The driving method includes: Obtain the load torque current; The load torque current is filtered at a low frequency to obtain the filtered current. The regulating current is obtained based on the difference between the load torque current and the filtered current; The regulating current is input into the first PI controller to obtain the regulating frequency; The final given frequency is determined based on the sum of the adjusted frequency and the initially given frequency; The final given frequency is used as the motor's given frequency for speed loop control of the motor.

2. The driving method according to claim 1, characterized in that, The process of performing low-frequency filtering on the load torque current to obtain the filtered current includes: The load torque current and the actual frequency of the motor are input into the observer module to obtain the observed current; The observed current is subjected to low-frequency filtering to obtain the filtered current.

3. The driving method according to claim 2, characterized in that, After using the final given frequency as the motor's given frequency to perform speed loop control on the motor, the method further includes: The observed current is used as the feedforward current for current loop control.

4. A drive system for a large inertia flexible load transmission system, wherein the output end of the motor in the large inertia flexible load transmission system is connected to the load, characterized in that, The drive system includes: The acquisition module is used to acquire the load torque current; The filtering module is used to perform low-frequency filtering on the load torque current to obtain the filtered current. The first adjustment module is used to obtain the adjustment current based on the difference between the load torque current and the filtered current; The second adjustment module is used to input the adjustment current into the first PI controller to obtain the adjustment frequency; The third adjustment module is used to determine the final given frequency based on the sum of the adjustment frequency and the initial given frequency; The control module is used to perform speed loop control on the motor by using the final given frequency as the motor's given frequency.

5. The drive system according to claim 4, characterized in that, The filtering module includes: The observation unit is used to input the load torque current and the actual frequency of the motor into the observer module to obtain the observed current; A filtering unit is used to perform low-frequency filtering on the observed current to obtain the filtered current.

6. The drive system according to claim 5, characterized in that, After the control module uses the final given frequency as the motor's given frequency to perform speed loop control on the motor, it is also used for: The observed current is used as the feedforward current for current loop control.

7. An electronic device, characterized in that, include: Memory, used to store computer programs; A processor, configured to execute the computer program to implement the steps of the driving method for a large inertia flexible load transmission system as described in any one of claims 1 to 3.

8. A readable storage medium, characterized in that, The readable storage medium stores a computer program that, when executed by a processor, implements the steps of a driving method for a large inertia flexible load transmission system as described in any one of claims 1 to 3.

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