Multi-channel cooperative control method with self-disturbance rejection function

Abstract

This invention belongs to the field of multi-channel synchronous control and discloses a multi-channel cooperative control method with self-disturbance rejection (SDR) function. Specifically, it involves sorting the actual speeds of all channels, finding the maximum and minimum speeds to obtain the coupled speeds of the multiple channels, designing a multi-channel cooperative control strategy, and combining robust control design with a robust synchronous controller to design a multi-channel cooperative controller with SDR function. The motor controller uses the SDR-enabled multi-channel cooperative controller to calculate the PWM pulse width modulation signal required for motor speed control and sends it to the motor driver. This invention can effectively avoid the influence of excessively high or low instantaneous speeds of the multiple channels when load disturbances are introduced, enabling each channel in the multi-channel system to track its desired speed while achieving high-precision cooperative control with SDR function.

Description

Technical Field

[0001] This invention belongs to the field of multi-channel synchronous control, specifically relating to a multi-channel cooperative control method with self-disturbance rejection function. Background Technology

[0002] Multi-channel cooperative control is a widespread problem in industrial applications such as textiles, papermaking, and film winding. In multi-channel cooperative control systems, each channel is required to stably track its set position or velocity; simultaneously, the positions or velocities of the multiple channels should exhibit consistency or a certain proportion of cooperative control. However, in actual operation, multi-channel cooperative control systems are subject to changes in equipment parameters and load disturbances. These uncertainties affect the system's cooperative performance and reduce product quality. Therefore, given these uncertainties, designing and developing cooperative control methods with self-disturbance rejection capabilities is of significant research importance for addressing multi-channel cooperative control problems.

[0003] Currently, multi-channel cooperative control systems mainly employ methods such as master-slave control, parallel synchronous control, and ring-coupled synchronous control. However, these methods have some drawbacks. For instance, in parallel synchronous control, when one or more channels experience load disturbances, these disturbances are not fed back to other channels, making it difficult to achieve high cooperative control accuracy.

[0004] The patent (patent number 2022111555751), titled "A Finite-Time Robust Cooperative Control Method for Multi-Axis Systems Based on Disturbance Compensation," designs a cooperative control strategy for a multi-axis system based on external load disturbances and combines it with robust control to design a robust synchronization controller. Specifically, it first analyzes the disturbance-compensated multi-axis system cooperative control strategy to obtain trajectory synchronization error, trajectory disturbance compensation error, trajectory concentration error, and control objective. Then, it establishes a state-space model of the disturbance-compensated multi-axis system and combines the trajectory concentration error from the state-space model to obtain a finite-time robust cooperative controller for the disturbance-compensated multi-axis system. This method has high cooperative control accuracy and fast response speed, but it suffers from limitations due to the large number of parameters involved and the need for real-time monitoring of external load disturbances to compensate for disturbance errors. Therefore, a new approach to designing multi-channel cooperative control methods is needed. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a multi-channel cooperative control method with self-disturbance rejection function, so as to solve the problem of poor synchronization performance of existing multi-channel cooperative control systems, and to achieve high-precision self-disturbance rejection cooperative control while each channel in the multi-channel system tracks its own desired speed.

[0006] To address the aforementioned technical problems, this invention provides a multi-channel cooperative control method with self-interference rejection function. Each channel includes a motor controller, a motor driver, a sensor, and a motor. The specific process of the method is as follows:

[0007] First, the multi-channel cooperative control strategy with active disturbance rejection (ADDR) function is analyzed to obtain the speed feedback error of each channel and the maximum and minimum values ​​of the actual speed. Then, the speed coupling error of each channel is calculated, and the speed compensation error of each channel is calculated through the speed feedback error and speed coupling error. Then, the multi-channel cooperative controller with ADDR function is obtained by combining the speed compensation error of each channel. The motor controller of each channel uses the actual speed feedback from the sensor and the multi-channel cooperative controller with ADDR function to calculate the PWM pulse width modulation signal required for motor speed control and sends it to the motor driver to drive the motor to rotate, thereby realizing multi-channel ADDR cooperative control.

[0008] As an improvement to the multi-channel cooperative control method with self-disturbance rejection function of the present invention:

[0009] The analysis of the multi-channel cooperative control strategy with self-disturbance rejection function is as follows:

[0010] 1) Set the given rotational speed x for each channel d (t) and actual rotational speed x i The difference between (t) is taken as the speed feedback error θ of each channel. i (t);

[0011] Where, x i (t) represents the actual rotational speed of the i-th channel; θ i (t) represents the speed feedback error of the i-th channel;

[0012] 2) Sort and compare the actual rotational speeds of all channels in a loop as follows:

[0013]

[0014] Where, x i+1 (t) represents the actual rotational speed of the (i+1)th channel;

[0015] 3) Assuming there are N (N≥4) channels, obtain the maximum value of the actual rotational speed x of each channel according to equation (1). ma (t)=max{x1(t),…,x N (t)} and the minimum value of the actual rotational speed of each channel x mi (t)=min{x1(t),…,x N (t)}.

[0016] As a further improvement to the multi-channel cooperative control method with self-disturbance rejection function of the present invention:

[0017] The rotational speed coupling error of each channel is:

[0018]

[0019] Where, ρ i (t) represents the rotational speed coupling error of the i-th channel.

[0020] As a further improvement to the multi-channel cooperative control method with self-disturbance rejection function of the present invention:

[0021] The calculation of the speed compensation error is as follows:

[0022]

[0023] As a further improvement to the multi-channel cooperative control method with self-disturbance rejection function of the present invention:

[0024] The process of establishing the multi-channel cooperative controller with self-interference rejection function is as follows:

[0025] 1) The mathematical model for the i-th channel with external load disturbance is:

[0026]

[0027] Where, x i (t) represents the actual rotational speed of the i-th channel, a i i is the electromagnetic torque coefficient. q,i (t) represents the q-axis stator current, p i J is the number of pole pairs of the motor. i Let d be the moment of inertia. i (t) represents the external load torque, |d i (t)|<χ, where χ is a positive constant;

[0028] 2) The design of a multi-channel cooperative controller with self-interference rejection function is as follows:

[0029] Differentiating equation (3) gives:

[0030]

[0031] Among them, U i It is a multi-channel robust cooperative controller with self-disruption function;

[0032] Selecting variables Then when At that time, a multi-channel robust cooperative controller with self-disruption function is:

[0033]

[0034] Among them, h i It is a positive number.

[0035] The beneficial effects of this invention are mainly reflected in:

[0036] 1. The multi-channel cooperative control method with self-disturbance rejection function proposed in this invention can effectively avoid the impact of excessively large or low instantaneous speeds of multiple channels when load disturbances are introduced, thus reducing the performance of the system's cooperative control. Furthermore, to further reduce the impact of system uncertainties, this invention employs robust control combined with the designed multi-channel cooperative control strategy to design a robust synchronous controller, enabling each channel in the multi-channel system to track its desired speed while achieving high-precision cooperative control of the multi-channel system with self-disturbance rejection function.

[0037] 2. Compared with the prior art, the present invention does not require real-time monitoring of external load disturbances. It only needs to sort the actual speeds of all channels, find the maximum and minimum speeds, and obtain the coupled speeds of the multiple channels to design a multi-channel collaborative control strategy. The present invention has the advantages of mature means and convenient and fast monitoring of actual speeds. Attached Figure Description

[0038] The specific embodiments of the present invention will be further described in detail below with reference to the accompanying drawings.

[0039] Figure 1 This is a flowchart illustrating a multi-channel cooperative control method with self-disturbance rejection function according to the present invention.

[0040] Figure 2 The graph shows the speed synchronization error curve of the parallel cooperative control method using a multi-channel system in the experiment.

[0041] Figure 3 The speed synchronization error curve is shown for the cooperative control method based on disturbance compensation used in the experiment.

[0042] Figure 4 The speed synchronization error curve is shown for the multi-channel cooperative control method with self-disturbance rejection function of the present invention used in the experiment. Detailed Implementation

[0043] The present invention will be further described below with reference to specific embodiments, but the scope of protection of the present invention is not limited thereto:

[0044] Example 1: A multi-channel cooperative control method with self-disturbance rejection capability. The method sorts the actual rotational speeds of all channels, finds the maximum and minimum speeds to obtain the coupled rotational speeds of the multiple channels, and designs a multi-channel cooperative control strategy. Combined with robust control, a robust synchronous controller is designed to complete the design of the multi-channel cooperative control method with self-disturbance rejection capability. The specific process is as follows: Figure 1 As shown, it includes the following steps:

[0045] Step S101: Analysis of a multi-channel cooperative control method with active disturbance rejection capability, including:

[0046] 1) The given rotational speed x of the multi-channel... d (t) and actual rotational speed x i The difference between (t) and (t) is taken as the multi-channel speed feedback error θ. i (t);

[0047] Where, x i (t) represents the actual rotational speed of the i-th channel, θ i (t) represents the speed feedback error of the i-th channel.

[0048] 2) Sort and compare the actual rotational speeds of all channels in a loop as follows:

[0049]

[0050] Where, x i+1 (t) represents the actual rotational speed of the (i+1)th channel.

[0051] 3) Assuming there are N (N≥4) channels, obtain the maximum value of the actual rotational speed x of each channel according to equation (1). ma (t)=max{x1(t),…,x N (t)} and the minimum value of the actual rotational speed of each channel x mi (t)=min{x1(t),…,x N (t)}. In multi-channel coordinated control, when load disturbances are introduced, it is found that the real-time monitored speed is momentarily too large or too small, and it is necessary to find the maximum and minimum values.

[0052] Step S102: Based on the cooperative control method in step S101, obtain the coupled rotational speeds of the multiple channels and calculate the rotational speed coupling error of each channel, specifically:

[0053]

[0054] Where, ρ i(t) represents the speed coupling error of the i-th channel. The calculation of Equation (2) avoids the need to add the influence of excessively large or small instantaneous speed of multiple channels when the load disturbance is too large or too small due to the external load disturbance compensation method of the real-time monitoring system, which is conducive to improving the collaborative control performance of multiple channels.

[0055] Step S103: Calculate the speed compensation error of each channel based on the speed feedback error and speed coupling error of each channel, specifically as follows:

[0056]

[0057] Step S104: Design a robust synchronous controller by combining the speed compensation error of each channel to complete the design of a multi-channel cooperative controller with self-disruption function:

[0058] 1) The mathematical model for the i-th channel with external load disturbance is:

[0059]

[0060] Where, x i (t) represents the actual rotational speed of the i-th channel, a i i is the electromagnetic torque coefficient. q,i (t) represents the q-axis stator current, p i J is the number of pole pairs of the motor. i Let d be the moment of inertia. i (t) represents the external load torque, |d i (t)|<χ, where χ is a positive constant.

[0061] 2) The design of a multi-channel cooperative controller with self-interference rejection function is as follows:

[0062] Differentiating equation (3) gives:

[0063]

[0064] Among them, U i It is a multi-channel robust cooperative controller with self-disruption function.

[0065] Selecting variables Then when At that time, the designed multi-channel robust cooperative controller with self-disturbance rejection function is as follows:

[0066]

[0067] Among them, h i It is a positive number.

[0068] Step S105: Multi-channel cooperative control with self-disturbance rejection function when there are uncertainties in the multi-channel system.

[0069] This paper introduces a multi-channel cooperative control method with self-disruption capability, applied to a multi-channel cooperative control system composed of multiple motors. The existing motors collect sensor information, control commands, and multi-channel coupling information through a controller, process these, and then transmit the control signal to the motor driver to drive the motor rotation. The controller, motor driver, and sensors used are typically powered by voltage conversion; the controller outputs a PWM wave; the sensors mainly include encoders, Hall voltage and current sensors, etc.; the motor driver outputs three-phase AC to directly drive the motor rotation. The motor body, controller, motor driver, and sensors are mature products and readily available commercially. For example, a servo motor body and motor driver from Yaskawa Electric Corporation (model SGDV-7R6A21A), a TMSC320F2812 DSP controller from TI, an E40S6-5000 encoder, and an AHBC-LTA series Hall current sensor are used, etc.

[0070] The controller (TMSC320F2812 DSP) uses the real speed feedback from the sensor and the multi-channel robust cooperative controller with self-disruption function designed in step S104 to calculate and process the PWM pulse width modulation signal required for motor speed control. The PWM signal is then sent to the motor driver to drive and control the motor speed, thereby realizing the cooperative control of the multi-channel system.

[0071] Experiment 1:

[0072] The multi-channel cooperative control method with self-disturbance rejection function described in Example 1 was used to conduct simulation experiments to verify a multi-channel cooperative control system composed of 6 motors. In the experiment, the rotational inertia of the 6 motors were set slightly differently (as shown in Table 1) to reflect the changes in equipment parameters in the system. The desired speed of the 6-motor system was 1000 r / min. Furthermore, when 0.1 ≤ t ≤ 0.2 s, different external load disturbances were added to the multi-channel system based on the cooperative control method of this invention, as shown in Table 2. To verify the effectiveness of the cooperative control method of this invention, the invention compared it with "Pan Liang. Research on Multi-Motor Synchronous Control Method Based on Fuzzy Control [D]. Donghua University, 2016" (referred to as the Parallel Cooperative Control Method of Multi-Channel System) and Patent No. 2022111555751 "A Finite-Time Robust Cooperative Control Method for Multi-Axis System Based on Disturbance Compensation" (referred to as the Cooperative Control Method Based on Disturbance Compensation). The simulation results include the speed synchronization error curves of the 6 channels. The simulation experimental results are as follows: Figures 2 to 4 As shown.

[0073] Table 1 shows the rotational inertia of the six motors, set to different values.

[0074] parameter Channel 1 Second Channel Channel 3 Channel 4 Channel 5 Channel 6 <![CDATA[J(kg·m 2 )]]> 0.008 0.0078 0.0076 0.0073 0.0082 0.0084

[0075] Table 2. External load disturbances acting on the multi-channel coordinated control system

[0076]

[0077] Depend on Figures 2-4 The comparison results show that the speed synchronization error based on the present invention is significantly smaller than that of the parallel cooperative control method of the multi-channel system, but the difference between the speed synchronization error and that of the cooperative control method based on disturbance compensation is very small. At the same time, the speed synchronization error of the multi-channel system based on the cooperative method of the present invention remains within a small range under continuous disturbance. This indicates that the multi-channel system constructed based on the multi-channel cooperative control method with self-disturbance rejection function described in the present invention has high cooperative control accuracy and strong robustness.

[0078] Finally, it should be noted that the above examples are merely some specific embodiments of the present invention. Obviously, the present invention is not limited to the above embodiments and many variations are possible. All variations that can be directly derived or conceived by those skilled in the art from the disclosure of the present invention should be considered within the scope of protection of the present invention.

Claims

1. A multi-channel cooperative control method with self-disruption function, wherein each channel includes a motor controller, a motor driver, a sensor, and a motor, characterized in that: The process includes the following: First, the multi-channel cooperative control strategy with active disturbance rejection (ADDR) function is analyzed to obtain the speed feedback error of each channel and the maximum and minimum values ​​of the actual speed. Then, the speed coupling error of each channel is calculated, and the speed compensation error of each channel is calculated through the speed feedback error and speed coupling error. Then, the multi-channel cooperative controller with ADDR function is obtained by combining the speed compensation error of each channel. The motor controller of each channel uses the actual speed feedback from the sensor and the multi-channel cooperative controller with ADDR function to obtain the PWM pulse width modulation signal required for motor speed control and sends it to the motor driver to drive the motor to rotate, thereby realizing multi-channel ADDR cooperative control. The design of a multi-channel cooperative controller with self-interference rejection function is as follows: Differentiating equation (3) gives: Among them, U i It is a multi-channel robust cooperative controller with self-disruption function; Selecting variables Then when At that time, a multi-channel robust cooperative controller with self-disruption function is: Where, η i It is a positive number.

2. The multi-channel cooperative control method with self-disturbance rejection function according to claim 1, characterized in that: The analysis of the multi-channel cooperative control strategy with self-disturbance rejection function is as follows: 1) Set the given rotational speed x for each channel d (t) and actual rotational speed x i The difference between (t) is taken as the speed feedback error θ of each channel. i (t); Where, x i (t) represents the actual rotational speed of the i-th channel; θ i (t) represents the speed feedback error of the i-th channel; 2) Sort and compare the actual rotational speeds of all channels in a loop as follows: Where, x i+1 (t) represents the actual rotational speed of the (i+1)th channel; 3) Assuming there are N channels, N≥4, obtain the maximum value of the actual rotational speed x of each channel according to equation (1). ma (t)=max{x1(t),…,x N (t)} and the minimum value of the actual rotational speed of each channel x mi (t)=min{x1(t),…,x N (t)}.

3. The multi-channel cooperative control method with self-disturbance rejection function according to claim 2, characterized in that: The rotational speed coupling error of each channel is: Where, ρ i (t) represents the rotational speed coupling error of the i-th channel.

4. The multi-channel cooperative control method with self-disturbance rejection function according to claim 3, characterized in that: The calculation of the speed compensation error is as follows:

5. A multi-channel cooperative control method with self-disturbance rejection function according to claim 4, characterized in that... The process of establishing a multi-channel cooperative controller with self-interference rejection function is as follows: The mathematical model for the i-th channel with external load disturbance is: Where, x i (t) represents the actual rotational speed of the i-th channel, a i i is the electromagnetic torque coefficient. q,i (t) represents the q-axis stator current, p i J is the number of pole pairs of the motor. i Let d be the moment of inertia. i (t) represents the external load torque, |d i (t)|<χ, where χ is a positive constant.

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