Motor speed controller and design method, motor control method, equipment and medium

Abstract

The present invention relates to a motor speed controller and design method, a motor control method, a device and a medium, the method comprising: rewriting the motor mechanical equation into a motor model in the form of a total disturbance differential equation, considering the motor angle dynamics and based on the total disturbance assumption of the constant slope ramp characteristic, deriving the differential equation group of the motor control system; expanding the integral of the motor mechanical angle into an additional state quantity, designing a corresponding high-order generalized proportional integral observer according to the differential equation group of the motor control system; designing a linear anti-disturbance controller according to the speed and total disturbance value observed by the high-order generalized proportional integral observer, so as to perform motor speed anti-disturbance control. Compared with the prior art, the present invention can realize the observation of ramp disturbance without static error and can well suppress its disturbance to the speed. Since the proposed anti-disturbance control algorithm has only a lower limit on the moment of inertia mismatch, it has the advantage of high robustness.

Description

Technical Field

[0001] The present invention relates to the field of motor control, and in particular to a motor speed controller and a design method, a motor control method, a device and a medium. Background Art

[0002] In recent years, with the development of industrial technology and the demand for higher precision in motor control, higher requirements have been placed on the performance of motor controllers: an ideal speed controller should have optimal speed reference tracking, external disturbance rejection, measurement noise rejection, and strong parameter robustness. Speed ​​control is usually nonlinear and time-varying due to model parameter uncertainty and external disturbances, including cogging torque, friction torque, and unknown load torque.

[0003] In terms of system robustness, in order to meet these performance requirements of industrial drive systems, electrical engineers use two methods: one method is to use online parameter identification to estimate the corresponding parameters in the motor mechanical equation; the other method is to use a robust controller instead of a traditional proportional-integral controller to achieve better performance. Researchers have tried various robust controllers to cope with parameter uncertainty without reducing the accuracy and rapidity of speed control. It is usually divided into passive and active anti-disturbance control. Since the active anti-disturbance controller can suppress interference without compromising system performance, it has won the favor of more engineers and researchers.

[0004] Active disturbance rejection controllers usually require the design of disturbance observers to suppress system disturbances by accurately observing the disturbances and feeding them forward to the controller output. However, the parameters of these observers are difficult to adjust because they need to obtain the motor's moment of inertia that changes with load, and a large mismatch in the moment of inertia parameters will cause system instability. The above shows that the traditional active disturbance rejection controller design is still difficult to meet the requirements for speed loop robustness. Summary of the invention

[0005] The purpose of the present invention is to overcome the defects of the above-mentioned prior art and provide a more robust motor speed controller and design method, motor control method, device and medium.

[0006] The purpose of the present invention can be achieved by the following technical solutions:

[0007] According to a first aspect of the present invention, a method for designing a motor speed controller is provided, the method comprising:

[0008] The motor mechanical equations are rewritten into a motor model in the form of a total disturbance differential equation, and the motor angle dynamics are considered. Based on the total disturbance assumption of the constant slope ramp characteristic, the differential equations of the motor control system are derived;

[0009] The integral of the motor mechanical angle is expanded into an additional state quantity, and the corresponding high-order generalized proportional integral observer is designed according to the differential equations of the motor control system;

[0010] According to the speed and total disturbance value observed by the high-order generalized proportional-integral observer, a linear active disturbance rejection controller is designed to perform active disturbance rejection control of the motor speed.

[0011] Preferably, the motor model of rewriting the motor mechanical equation into a total perturbation differential equation includes:

[0012] The mechanical equation of the motor is expressed as:

[0013]

[0014] Where: m is the motor mechanical angular velocity; ω m The first derivative of; B is the viscous damping coefficient; T e is the electromagnetic torque actually acting on the motor; T L is the load disturbance torque; J is the moment of inertia of the system;

[0015] The motor model expression in the form of the total disturbance differential equation after rewriting is:

[0016]

[0017] in: J is the electromagnetic torque command output by the motor speed controller; n The parameters set for the controller, and is defined as a regular disturbance, is defined as the total disturbance of the system.

[0018] Preferably, the motor angle dynamics are considered, based on the total disturbance assumption of the constant slope ramp characteristic, to derive a differential equation group of the motor control system, which is expressed as:

[0019]

[0020] Where: θ m is the mechanical angle of the motor; k is the derivative of the total disturbance with respect to time, that is, the slope of the ramp-type disturbance.

[0021] Preferably, the step S3 is specifically:

[0022] Expand the integral of the motor mechanical angle to an additional state quantity ψ m ,satisfy The superscript ^ indicates an estimated value, and the superscript ~ indicates an estimated difference;

[0023] According to the differential equations of the motor control system, the corresponding high-order generalized proportional integral observer is designed, and the expression is:

[0024]

[0025] Where: l0~l3 are the error feedback gains of the observer; ω m is the motor mechanical angular velocity; It is the electromagnetic torque command output by the motor speed controller.

[0026] Preferably, the linear active disturbance rejection controller expression is:

[0027]

[0028] Where: K p is the proportional coefficient of the speed controller; is the reference value of the motor mechanical angular velocity; It is the estimated value of the motor mechanical angular velocity output by the high-order generalized proportional-integral observer; is the total disturbance estimate of the system output by the high-order generalized proportional-integral observer.

[0029] Preferably, the method further comprises determining a control parameter selection range according to a system stability condition, and the specific process is as follows:

[0030] Considering load disturbance d n and the angle measurement noise θ n , the transfer function of the speed closed loop is derived from equations (4) and (5):

[0031]

[0032] Where: k b =b n / b, s is the Laplace transform symbol; P4 = s 4 +l0s 3 +l1s 2 +2l2s+l3 is defined as the characteristic equation of the observer, G3=P4+(K p G1-G2)s 2 , a=sG3(k b -1)+(s+K p )P4 is defined as the closed-loop characteristic equation of the system;

[0033] Simplifying the closed-loop characteristic equation, we get:

[0034] a=k b s 5 +k b a4s 4 +k b a3s3 +(k2+k b a2)s 2 +a1s+a0 (7)

[0035] Where: a4=K p +l0,a3=K p l0+l1,a2=l2+K p l1, a1=l3+2K p l2,a0=K p l3;

[0036] The stability condition is derived using Routh criterion:

[0037]

[0038] set up So we have:

[0039]

[0040] According to the designed value of formula (9), a3a4-a2>0 in formula (8);

[0041] At the same time, the equation of the second stability condition in equation (8) is an upward-opening parabola. According to the zero point existence theorem, it must have a zero point in the interval (-∞,0] and [0,+∞). When k b When the value is greater than this positive zero, the second stability condition holds;

[0042] That is, when k b When it is greater than a certain set value, the two stability conditions in equation (8) must be satisfied. n When the setting value is less than a certain value, the proposed ADRC method can keep the speed control system stable.

[0043] According to a second aspect of the present invention, a motor speed controller is provided. The speed controller is a linear active disturbance rejection controller designed by any one of the above methods.

[0044] According to a third aspect of the present invention, there is provided a motor control method, the method comprising:

[0045] The collected mechanical angular velocity ω of the permanent magnet synchronous motor m Converted to motor mechanical angle θ m After that, it is input into the above-mentioned motor speed anti-disturbance controller to output the electromagnetic torque command

[0046] The output electromagnetic torque command Acts on the permanent magnet synchronous motor control model and outputs the estimated dq axis current

[0047] The real-time acquired three-phase current coordinates of the permanent magnet synchronous motor are converted into dq axis current i dq ;

[0048] The estimated dq axis current and the dq axis current i dq Input to the current loop controller, output dq axis voltage estimation value Output dq axis voltage estimation value Coordinates are converted to The PWM wave is then input to the space vector pulse width modulator, and the inverter switch is controlled by the modulated output PWM wave to form a three-phase current output of the permanent magnet synchronous motor.

[0049] According to a fourth aspect of the present invention, there is provided an electronic device, comprising a memory and a processor, wherein a computer program is stored in the memory, and when the processor executes the program, any one of the methods described above is implemented.

[0050] According to a fifth aspect of the present invention, there is provided a computer-readable storage medium having a computer program stored thereon, wherein the program implements any one of the methods described above when executed by a processor.

[0051] Compared with the prior art, the present invention has the following beneficial effects:

[0052] 1) The present invention introduces additional state variables to design a high-order generalized proportional-integral disturbance observer, which can achieve zero-static-error observation of ramp disturbances and effectively suppress their disturbances to the rotation speed.

[0053] 2) The motor speed anti-disturbance controller designed in the present invention has only a lower limit on the moment of inertia mismatch, and has the advantages of high robustness and strong parameter robustness. In application scenarios where the moment of inertia is unknown or changes, when the control parameter is greater than a certain value, the designed speed controller can completely resist the adverse effects caused by the moment of inertia mismatch of the immune system.

[0054] 3) Selecting a suitable motor speed is crucial to energy efficiency. Too high or too low a speed may lead to energy waste. The speed self-anti-disturbance controller designed in the present invention can achieve precise speed control and suppress the influence of disturbances on the speed, thereby improving energy utilization and achieving the purpose of energy saving. BRIEF DESCRIPTION OF THE DRAWINGS

[0055] Figure 1 It is a flow chart of a motor speed auto-disturbance rejection control method with strong parameter robustness of the present invention;

[0056] Figure 2It is a structural block diagram of the high-order generalized proportional-integral observer of the present invention;

[0057] Figure 3 It is a structural block diagram of the motor speed control system of the present invention;

[0058] Figure 4 It is the closed-loop root locus diagram of the speed control system. DETAILED DESCRIPTION

[0059] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0060] Example

[0061] like Figure 1 As shown, this embodiment provides a motor speed controller design method, the method comprising:

[0062] S1. Rewrite the motor mechanical equation into a motor model in the form of a total disturbance differential equation. Consider the motor angle dynamics and derive the differential equations of the motor control system based on the total disturbance assumption of the constant slope ramp characteristic, including:

[0063] The mechanical equation of the motor is expressed as:

[0064]

[0065] Where: m is the motor mechanical angular velocity; ω m The first derivative of; B is the viscous damping coefficient; T e is the electromagnetic torque actually acting on the motor; T L is the load disturbance torque; J is the moment of inertia of the system;

[0066] The motor model expression in the form of the total disturbance differential equation after rewriting is:

[0067]

[0068] in: J is the electromagnetic torque command output by the motor speed controller; n The parameters set for the controller, and is defined as a regular disturbance, is defined as the total disturbance of the system;

[0069] Considering the motor angle dynamics, based on the total disturbance assumption of the constant slope ramp characteristic, the differential equations of the motor control system are derived, which are expressed as:

[0070]

[0071] Where: θ m is the motor mechanical angle; k is the derivative of the total disturbance with respect to time, that is, the slope of the ramp type disturbance. It should be noted that the constant value disturbance is only a special case of the present invention.

[0072] S2. Expand the integral of the motor mechanical angle into an additional state quantity, and design the corresponding high-order generalized proportional integral observer according to the differential equations of the motor control system, specifically:

[0073] Expand the integral of the motor mechanical angle to an additional state quantity ψ m ,satisfy The superscript ^ indicates an estimated value, and the superscript ~ indicates an estimated difference;

[0074] According to the differential equations of the motor control system, the corresponding high-order generalized proportional integral observer is designed, and the expression is:

[0075]

[0076] Where: l0~l3 are the error feedback gains of the observer; ω m is the motor mechanical angular velocity; is the electromagnetic torque command output by the motor speed controller; the structural block diagram of the high-order generalized proportional integral observer is as follows Figure 2 shown.

[0077] The mechanical angular velocity of the motor observed by a high-order generalized proportional-integral observer Closed-loop feedback is performed, and the observed disturbance is Feedforward to the output of the linear active disturbance rejection controller to compensate for the impact of the disturbance. At this time, the expression of the linear active disturbance rejection controller is:

[0078]

[0079] Where: K p is the proportional coefficient of the speed controller; is the reference value of the motor mechanical angular velocity; It is the estimated value of the motor mechanical angular velocity output by the high-order generalized proportional-integral observer; is the total disturbance estimate of the system output by the high-order generalized proportional-integral observer.

[0080] S3. According to the speed and total disturbance value observed by the high-order generalized proportional-integral observer, a linear anti-disturbance control controller is designed to perform motor speed anti-disturbance control.

[0081] S4. Determine the range of control parameter selection according to the system stability conditions. The specific process is as follows:

[0082] Considering load disturbance d n and the angle measurement noise θ n , the transfer function of the speed closed loop can be derived from equations (4) and (5):

[0083]

[0084] Where: k b =b n / b, s is the Laplace transform symbol; P4 = s 4 +l0s 3 +l1s 2 +2l2s+l3 is defined as the characteristic equation of the observer, G3=P4+(K p G1-G2)s 2 , a=sG3(k b -1)+(s+K p )P4 is defined as the closed-loop characteristic equation of the system;

[0085] The stability condition of the linear system is: the poles of the closed-loop system are all in the left half plane of the s domain. Since the closed-loop characteristic equation of the system is a fifth-order equation, the stability condition of the system can be derived according to the Routh criterion. Simplifying the closed-loop characteristic equation, we get:

[0086] a=k b s 5 +k b a4s 4 +k b a3s 3 +(k2+k b a2)s 2 +a1s+a0 (7)

[0087] Where: a4=K p +l0,a3=K p l0+l1,a2=l2+K p l1, a1=l3+2K p l2,a0=K p l3;

[0088] The stability condition is derived using Routh criterion:

[0089]

[0090] set up So we have:

[0091]

[0092] According to the designed value of formula (9), a3a4-a2>0 in formula (8);

[0093] At the same time, the equation of the second stability condition in equation (8) is an upward-opening parabola. According to the zero point existence theorem, it must have a zero point in the interval (-∞,0] and [0,+∞). When k b When the value is greater than this positive zero, the second stability condition holds;

[0094] That is, when k b When it is greater than a certain set value, the two stability conditions in equation (8) must be satisfied. n When the setting value is less than a certain value, the proposed ADRC method can keep the speed control system stable.

[0095] To further verify the rigor of the proof, Figure 4 Shown in k b The root locus diagram of the speed closed-loop system with parameters is shown in the figure. It can be seen from the figure that when k b When is greater than a certain value, the poles of the closed-loop system are all in the left half plane of the s-domain, so the system must be stable.

[0096] This embodiment also provides a motor speed controller, which is a linear active disturbance rejection controller designed by the above method.

[0097] This embodiment also provides a motor control method, such as Figure 3 As shown, the method includes:

[0098] The collected mechanical angular velocity ω of the permanent magnet synchronous motor m Converted to motor mechanical angle θ m After that, it is input to the motor speed anti-disturbance controller mentioned above, and the electromagnetic torque command is output.

[0099] The output electromagnetic torque command Acts on the permanent magnet synchronous motor control model and outputs the dq axis current command value

[0100] The real-time acquired three-phase current coordinates of the permanent magnet synchronous motor are converted into dq axis current i dq ;

[0101] The estimated dq axis current and the dq axis current i dq Input to the current loop controller and output dq axis voltage command value Output dq axis voltage command value Coordinates are converted to The PWM wave is then input to the space vector pulse width modulator, and the inverter switch is controlled by the modulated output PWM wave to form a three-phase current output of the permanent magnet synchronous motor.

[0102] The electronic device of the present invention includes a central processing unit (CPU), which can perform various appropriate actions and processes according to computer program instructions stored in a read-only memory (ROM) or loaded from a storage unit into a random access memory (RAM). In the RAM, various programs and data required for device operation can also be stored. The CPU, ROM and RAM are connected to each other via a bus. An input / output (I / O) interface is also connected to the bus.

[0103] Multiple components in the device are connected to the I / O interface, including: input units, such as keyboards, mice, etc.; output units, such as various types of displays, speakers, etc.; storage units, such as disks, optical disks, etc.; and communication units, such as network cards, modems, wireless communication transceivers, etc. The communication unit allows the device to exchange information / data with other devices through computer networks such as the Internet and / or various telecommunication networks.

[0104] The processing unit performs the various methods and processes described above, such as methods S1 to S4. For example, in some embodiments, methods S1 to S4 may be implemented as a computer software program, which is tangibly contained in a machine-readable medium, such as a storage unit. In some embodiments, part or all of the computer program may be loaded and / or installed on the device via a ROM and / or a communication unit. When the computer program is loaded into the RAM and executed by the CPU, one or more steps of methods S1 to S4 described above may be performed. Alternatively, in other embodiments, the CPU may be configured to execute methods S1 to S4 in any other appropriate manner (e.g., by means of firmware).

[0105] The functions described above herein may be performed at least in part by one or more hardware logic components. For example, without limitation, exemplary types of hardware logic components that may be used include: field programmable gate arrays (FPGAs), application specific integrated circuits (ASICs), application specific standard products (ASSPs), systems on chip systems (SOCs), load programmable logic devices (CPLDs), and the like.

[0106] The program code for implementing the method of the present invention can be written in any combination of one or more programming languages. These program codes can be provided to a processor or controller of a general-purpose computer, a special-purpose computer or other programmable data processing device, so that the program code, when executed by the processor or controller, enables the functions / operations specified in the flow chart and / or block diagram to be implemented. The program code can be executed entirely on the machine, partially on the machine, partially on the machine as a stand-alone software package and partially on a remote machine, or entirely on a remote machine or server.

[0107] In the context of the present invention, a machine-readable medium may be a tangible medium that may contain or store a program for use by or in conjunction with an instruction execution system, device, or equipment. A machine-readable medium may be a machine-readable signal medium or a machine-readable storage medium. A machine-readable medium may include, but is not limited to, electronic, magnetic, optical, electromagnetic, infrared, or semiconductor systems, devices, or equipment, or any suitable combination of the foregoing. A more specific example of a machine-readable storage medium may include an electrical connection based on one or more lines, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.

[0108] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can easily think of various equivalent modifications or replacements within the technical scope disclosed by the present invention, and these modifications or replacements should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention shall be based on the protection scope of the claims.

Claims

1. A motor speed controller design method, characterized in that: The method comprises: The motor mechanical equation is rewritten into a motor model in the form of a total disturbance differential equation. Considering the motor angle dynamics, based on the total disturbance assumption of the constant slope ramp characteristic, the differential equation group of the motor control system is derived, which is: The motor model that rewrites the motor mechanical equation into the form of a total disturbance differential equation includes: The mechanical equation of the motor is expressed as: Where: m is the motor mechanical angular velocity; ω m The first derivative of; B is the viscous damping coefficient; T e is the electromagnetic torque actually acting on the motor; T L is the load disturbance torque; J is the moment of inertia of the system; The motor model expression in the form of the total disturbance differential equation after rewriting is: in: J is the electromagnetic torque command output by the motor speed controller; n is the parameter set for the controller, and b n =1 / J n ; b = 1 / J; is defined as a regular disturbance, is defined as the total disturbance of the system; The integral of the motor mechanical angle is expanded into an additional state quantity, and the corresponding high-order generalized proportional integral observer is designed according to the differential equations of the motor control system, specifically: Considering the motor angle dynamics, based on the total disturbance assumption of the constant slope ramp characteristic, the differential equations of the motor control system are derived, and the expression is: Where: θ m is the motor mechanical angle; k is the derivative of the total disturbance with respect to time, that is, the slope of the ramp-type disturbance; Expand the integral of the motor mechanical angle to an additional state quantity ψ m ,satisfy The superscript ^ indicates an estimated value, and the superscript ~ indicates an estimated difference; According to the differential equations of the motor control system, the corresponding high-order generalized proportional integral observer is designed, and the expression is: Where: l0~l3 are the error feedback gains of the observer; ω m is the motor mechanical angular velocity; It is the electromagnetic torque command output by the motor speed controller; According to the speed and total disturbance value observed by the high-order generalized proportional integral observer, a linear active disturbance rejection controller is designed to perform motor speed active disturbance rejection control; the linear active disturbance rejection controller expression is: Where: K p is the proportional coefficient of the speed controller; is the reference value of the motor mechanical angular velocity; It is the estimated value of the motor mechanical angular velocity output by the high-order generalized proportional-integral observer; is the total disturbance estimate of the system output by the high-order generalized proportional-integral observer.

2. A motor speed controller design method according to claim 1, characterized in that: The method further includes determining a control parameter selection range according to a system stability condition, and the specific process is as follows: Considering load disturbance d n and the angle measurement noise θ n , the transfer function of the speed closed loop is derived from equations (4) and (5): Where: k b =b n / b, s is the Laplace transform symbol; P4 = s 4 +l0s 3 +l1s 2 +2l2s+l3 is defined as the characteristic equation of the observer, G3=P4+(K p G1-G2)s 2 , a=sG3(k b -1)+(s+K p )P4 is defined as the closed-loop characteristic equation of the system; Simplifying the closed-loop characteristic equation, we get: a=k b s 5 +k b a4s 4 +k b a3s 3 +(k2+k b a2)s 2 +a1s+a0 (7) where: a4 = K p + l0, a3 = K p l0 + l1, a2 = l2 + K p l1, a1 = l3 + 2K p l2, a0 = K p l3; The stability condition is derived using Routh criterion: set up So we have: According to the designed value of formula (9), a3a4-a2>0 in formula (8); At the same time, the equation of the second stability condition in equation (8) is an upward-opening parabola. According to the zero point existence theorem, it must have a zero point in the interval (-∞,0] and [0,+∞). When k b When the value is greater than this positive zero, the second stability condition holds; That is, when k b When it is greater than a certain set value, the two stability conditions in formula (8) must be satisfied; therefore, when J n When the setting value is less than a certain value, the proposed ADRC method can keep the speed control system stable.

3. A motor speed controller, characterized in that: The speed controller is a linear active disturbance rejection controller designed by the method described in any one of claims 1 to 2.

4. A motor control method, characterized in that: The method includes: The collected mechanical angular velocity ω of the permanent magnet synchronous motor m Converted to motor mechanical angle θ m After that, it is input to the motor speed anti-disturbance controller according to claim 3, and the electromagnetic torque instruction is output. The output electromagnetic torque command Acts on the permanent magnet synchronous motor control model and outputs the estimated dq axis current The real-time acquired three-phase current coordinates of the permanent magnet synchronous motor are converted into dq axis current i dq ; The estimated dq axis current and the dq axis current i dq Input to the current loop controller, output dq axis voltage estimation value Output dq axis voltage estimation value Coordinates are converted to The PWM wave is then input to the space vector pulse width modulator, and the inverter switch is controlled by the modulated output PWM wave to form a three-phase current output of the permanent magnet synchronous motor.

5. An electronic device comprising a memory and a processor, wherein a computer program is stored in the memory, wherein: When the processor executes the program, the method according to any one of claims 1 to 2 is implemented.

6. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the program is executed by a processor, the method according to any one of claims 1 to 2 is implemented.

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