Shearing machine direct current motor speed regulation method based on industrial control system

Abstract

The invention relates to the crossing field of mechanical engineering and industrial control systems, and discloses a shearing machine direct current motor speed regulation method based on an industrial control system. According to the method, a transmission-chain-free direct drive framework is constructed, and multi-source state data are collected in real time through a strain type torque sensor, a photoelectric encoder and a temperature and humidity sensor; a target rotating speed is dynamically set by combining process parameters, a speed regulation instruction is generated by adopting a feedforward-feedback composite control strategy, and a full-bridge power circuit is driven through pulse width modulation to realize millisecond-level rotating speed closed-loop regulation. The system integrates online parameter identification and a visual quality feedback correction mechanism, and the shearing uniformity, the energy efficiency and the operation stability are improved.

Description

Technical Field

[0001] This invention belongs to the interdisciplinary field of mechanical engineering and industrial control systems, and specifically relates to a method for speed regulation of DC motors in a shearing machine based on an industrial control system. Background Technology

[0002] With the continuous improvement of industrial automation, shearing machines, as key equipment in the textile, leather, and precision manufacturing fields, face increasingly stringent requirements for processing accuracy and dynamic response performance. Traditional shearing machines generally employ a structure where a DC motor, combined with a mechanical reducer, drives the shearing blades, and speed control is achieved by adjusting the armature voltage. While this meets basic operational requirements to a certain extent, its inherent multi-stage transmission chain introduces additional mechanical losses, backlash errors, and inertial delays, which not only reduce the overall energy efficiency of the system but also weaken its rapid response capability to load disturbances.

[0003] The shearing process places extremely high demands on the real-time performance and stability of the cutter speed, especially when faced with sudden changes in fabric thickness or uneven fiber density, where the load torque may experience sudden and drastic fluctuations. Existing speed control systems based on reduction gears suffer from mechanical buffering, causing the motor output to be unable to be transmitted to the cutter tip in a timely manner, resulting in speed lag and subsequently leading to problems such as uneven shearing, surface damage, or equipment vibration. Traditional open-loop or simple closed-loop current control strategies struggle to accurately perceive the actual operating state of the load side and cannot dynamically adjust the armature voltage based on real-time current feedback, leaving the system lacking adaptive adjustment capabilities in highly dynamic scenarios.

[0004] In existing technologies, although some high-end equipment attempts to introduce servo control systems to improve response performance, these still largely rely on complex encoder feedback and position loop designs, resulting in high costs and structural redundancy. Meanwhile, the presence of the reducer remains a fundamental limitation on system rigidity and response speed. Therefore, while ensuring control accuracy, there is an urgent need for a novel speed control method that eliminates intermediate transmission links, directly couples the motor and load, and deeply integrates current closed-loop feedback to solve the problems of response lag and transmission loss faced by shearing machines in high-precision, high-dynamic application scenarios. Summary of the Invention

[0005] This invention provides a DC motor speed control method for a wool shearing machine based on an industrial control system. It aims to solve the technical problems of traditional speed control systems, such as transmission chain losses and delayed response to sudden load changes, which fail to meet the real-time speed control requirements of high-precision wool shearing. The method constructs a transmission chain-free direct-drive power architecture and combines multi-source state sensing with a feedforward-feedback composite control strategy to achieve millisecond-level dynamic adjustment of the DC motor speed of the wool shearing machine. This ensures a constant shearing linear speed under different wool densities, humidity levels, and thicknesses, thereby improving the consistency of shearing quality and equipment energy efficiency.

[0006] The present invention provides a method for speed control of a DC motor in a shearing machine based on an industrial control system, comprising: Acquire real-time load torque signal of the shearing machine's cutter roller, motor rotor angular velocity signal, ambient temperature and humidity data, and current shearing process parameters; Based on the deviation between the real-time load torque signal and the preset reference load threshold, a feedforward compensation voltage command is generated. The motor rotor angular velocity signal is compared with the target speed setpoint to obtain the speed error signal, which is then input to the proportional-integral-derivative controller to output a feedback adjustment voltage command. The feedforward compensation voltage command and the feedback regulation voltage command are algebraically superimposed to form a composite speed regulation voltage command. The composite speed regulation voltage command is converted into a duty cycle adjustable switching drive signal by the pulse width modulation module and applied to the power drive circuit of the DC motor to adjust the motor armature voltage in real time and realize closed-loop speed control.

[0007] Preferably, the acquisition of the real-time load torque signal of the shearing machine's cutter roller is specifically achieved by a strain gauge torque sensor installed on the cutter roller's main shaft. The output signal of the strain gauge torque sensor is processed by an anti-aliasing low-pass filter and then sent to the analog input channel of the industrial controller.

[0008] Preferably, the motor rotor angular velocity signal is acquired by an incremental photoelectric encoder, which obtains a pulse signal after a 4x frequency multiplication through an orthogonal decoding circuit, and calculates the instantaneous angular velocity using a time interval measurement method.

[0009] Preferably, the ambient temperature and humidity data are acquired by a digital temperature and humidity sensor located within the shearing work area.

[0010] Preferably, the current shearing process parameters include wool type identification, target shearing length, feed speed setting value, and blade sharpness level, which are input to the industrial controller through a human-machine interface or a host computer system interface and stored in non-volatile memory for dynamically adjusting the target speed setting value.

[0011] Preferably, the preset benchmark load threshold is dynamically determined based on the current shearing process parameters, and the calculation formula is as follows: ; The baseline load threshold, For the target shear length, For the feed rate, This is the blade sharpness attenuation coefficient. , , These are the process weighting coefficients obtained through offline calibration.

[0012] Preferably, the process of generating the feedforward compensation voltage command includes: inputting the difference between the real-time load torque signal and the reference load threshold to the feedforward gain module, wherein the gain coefficient of the feedforward gain module is... Determined by the following formula: ; For the armature resistance of a DC motor, The torque constant of the motor. To improve the mechanical efficiency of the integrated motor and cutter roller structure. Updated in real time via an online resistance identification algorithm. and The parameters are calibrated and fixed in the controller parameter library when the equipment leaves the factory.

[0013] Preferably, the parameter tuning of the proportional-integral-derivative controller adopts an adaptive law. The proportional gain, integral time constant and derivative time constant are dynamically switched according to the current speed range, divided into three ranges: low speed range, medium speed range and high speed range. The parameters of each range are configured independently, and a smooth transition algorithm is used during the switching process to avoid abrupt changes in the control quantity.

[0014] Preferably, before each shearing operation begins, an online motor parameter identification program is executed, including the identification of armature resistance, back electromotive force constant, and moment of inertia. The identification process is carried out under no-load conditions. By applying a step voltage excitation and recording the current and speed response curves, the system transfer function parameters are fitted using the least squares method. The identification results are used to update the feedforward gain module and the controller parameter library.

[0015] Preferably, the method further includes a shearing quality feedback correction mechanism: a visual inspection device is set at the shearing exit to collect images of the wool surface after shearing in real time, and the surface roughness index is extracted by the image processing algorithm. If the surface roughness index exceeds the preset tolerance zone three times in a row, the target rotation speed setting value is automatically adjusted until the surface roughness returns to the qualified range.

[0016] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. By eliminating the intermediate transmission links such as traditional belts and gears, and adopting an integrated direct drive structure of motor and cutter roller, the energy loss and mechanical backlash of the transmission chain are completely eliminated, thereby improving the system rigidity and response speed; 2. A feedforward compensation mechanism based on real-time load torque is introduced to effectively offset the speed disturbance caused by sudden load changes and shorten the speed recovery time. 3. By combining adaptive proportional-integral-derivative feedback control with the target speed setting linked to process parameters, the shearing machine can maintain the optimal shearing linear speed under different working conditions. 4. Integrating online parameter identification and visual quality feedback correction forms a closed-loop optimization system of "perception-decision-execution-verification", improving shearing uniformity, equipment energy efficiency and long-term operational stability, and meeting the requirements of high-end textile processing. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the overall technical solution architecture of the present invention; Figure 2 This is a schematic diagram of the core principle framework of the feedforward-feedback composite control strategy in this invention; Figure 3 This is a flowchart illustrating the logical flow of multi-source state perception and dynamic setting of target rotation speed in this invention. Figure 4 This is a flowchart illustrating the logical flow of online motor parameter identification and adaptive controller tuning in this invention. Figure 5 This is a schematic diagram of the multi-level interaction relationship and data flow of visual feedback correction and closed-loop optimization of shearing quality in this invention. Detailed Implementation

[0018] refer to Figures 1 to 5 This invention provides a DC motor speed control method for a wool shearing machine based on an industrial control system. It aims to solve the technical problems of traditional speed control systems, such as transmission chain losses and delayed response to sudden load changes, which fail to meet the real-time speed control requirements of high-precision wool shearing. The method constructs a transmission chain-free direct-drive power architecture and combines multi-source state sensing with a feedforward-feedback composite control strategy to achieve millisecond-level dynamic adjustment of the DC motor speed of the wool shearing machine. This ensures a constant shearing linear speed under different wool densities, humidity levels, and thicknesses, thereby improving the consistency of shearing quality and equipment energy efficiency.

[0019] As one embodiment of the present invention, the speed control method for a DC motor of a shearing machine based on an industrial control system includes the following steps: acquiring the real-time load torque signal of the shearing machine's cutting roller, the motor rotor angular velocity signal, ambient temperature and humidity data, and current shearing process parameters; generating a feedforward compensation voltage command based on the deviation between the real-time load torque signal and a preset reference load threshold; comparing the motor rotor angular velocity signal with a target speed setpoint to obtain a speed error signal, and inputting it to a proportional-integral-derivative controller to output a feedback adjustment voltage command; algebraically superimposing the feedforward compensation voltage command and the feedback adjustment voltage command to form a composite speed control voltage command; converting the composite speed control voltage command into a duty cycle adjustable switching drive signal via a pulse width modulation module, and applying it to the power drive circuit of the DC motor to adjust the motor armature voltage in real time and achieve closed-loop speed control.

[0020] In the above method, the specific execution process of acquiring the real-time load torque signal of the shearing machine's cutter roller, the motor rotor angular velocity signal, ambient temperature and humidity data, and the current shearing process parameters is as follows. First, the real-time load torque signal is acquired by a strain gauge torque sensor installed on the cutter roller's main shaft. This strain gauge torque sensor is directly integrated into the rotating main shaft of the integrated structure of the cutter roller and the DC motor rotor. Its measurement range covers 0 to 500 Nm, and the sampling frequency is not less than 2 kHz, ensuring accurate capture of instantaneous torque fluctuations caused by wool fiber entanglement, density changes, or blade wear during the shearing process. The analog voltage signal output by the sensor is processed by an anti-aliasing low-pass filter with a cutoff frequency of 1 kHz to suppress high-frequency electromagnetic interference and mechanical vibration noise. It is then sent to the 16-bit high-precision analog input channel of the industrial controller to complete analog-to-digital conversion and store it in the real-time data buffer.

[0021] The motor rotor angular velocity signal is acquired by an incremental photoelectric encoder. This incremental photoelectric encoder is directly mounted on the output shaft of the DC motor and rigidly connected coaxially to the cutter roller, with a resolution of 5,000 lines per revolution. The two orthogonal square wave signals output by the encoder, phases A and B, are connected to a dedicated quadrature decoding circuit. After being frequency multiplied by 4, the effective resolution is increased to 20,000 pulses per revolution. The time interval measurement unit inside the industrial controller performs high-precision timing of the time interval between the rising edges of adjacent pulses with a period of 500 microseconds, using a formula... Calculate instantaneous angular velocity , This represents the pulse count value per unit time. For the measurement period, This is the internal clock frequency. The update period for the motor rotor angular velocity calculation is no more than 1 millisecond, ensuring that the speed feedback signal has sufficient dynamic response capability.

[0022] Ambient temperature and humidity data are acquired by a digital temperature and humidity sensor located within the shearing work area. This sensor is mounted on a bracket 50 mm in front of the shear roller, directly exposed to the airflow path through which the wool being processed passes. The temperature measurement range is -10°C to 60°C, with an accuracy of ±0.5°C; the humidity measurement range is 10% to 95% relative humidity, with an accuracy of ±3% relative humidity. The sensor communicates with the industrial controller via a single-bus protocol, with a data update cycle of 500 milliseconds. The acquired temperature and humidity data is used to correct the physical property model of the wool fibers, indirectly affecting the dynamic adjustment logic of the target rotation speed setpoint.

[0023] The current shearing process parameters include wool type identification, target shearing length, feed speed setting, and blade sharpness level. These parameters are input to the industrial controller via an Ethernet interface through the human-machine interface panel or a host computer system. Wool type identification uses a predefined coding system, such as codes 1, 2, and 3 for fine wool, semi-fine wool, and coarse wool, respectively; the target shearing length is in millimeters, ranging from 0.5 to 5 millimeters; the feed speed setting is in meters per minute, ranging from 10 to 60; the blade sharpness level is initially set to level one and automatically downgrades over time. All process parameters are written into the industrial controller's built-in non-volatile memory and loaded into the running memory each time a job is started, serving as the basis for subsequent dynamic setting of the target speed.

[0024] After acquiring the aforementioned multi-source data, the process proceeds to the generation stage of the feedforward compensation voltage command. This generation stage applies a compensation voltage in advance to counteract load disturbances based on the deviation between the real-time load torque and a preset reference load threshold. The preset reference load threshold is not a fixed value but is dynamically determined based on the current shearing process parameters. Its calculation follows the formula below: ; The baseline load threshold, For the target shear length, For the feed rate, This is the blade sharpness attenuation coefficient. , , These are the process weighting coefficients obtained through offline calibration. Characterizes the inverse proportional effect of shear length on load, with a value ranging from 80 to 120; It reflects the linear contribution of the feed rate to the load, with a value ranging from 0.3 to 0.6; The value ranges from 5 to 15, reflecting the additional effect of blade dulling on the load. The blade sharpness attenuation coefficient initially has a value of 1, which decreases linearly with the cumulative shearing area. When the cumulative shearing area reaches 100,000 square meters, the attenuation coefficient drops to 0.6. The cumulative shearing area is obtained in real time by summing the product of the feed rate and the operation time, and is stored in non-volatile memory, which is not lost when power is off.

[0025] The real-time load torque signal is algebraically subtracted from the aforementioned dynamic reference load threshold to obtain the load deviation. This load deviation is input to the feedforward gain module to generate a feedforward compensation voltage command. (Feedforward gain coefficient) The determination is based on the electromechanical coupling relationship of the DC motor, and its expression is: ; For the armature resistance of a DC motor, The torque constant of the motor. The mechanical efficiency of the integrated motor and cutter roller structure. and The equipment is calibrated using a standard test bench at the factory and the parameters are fixed in the controller parameter library and cannot be changed. The system then updates in real time using an online resistance identification algorithm to compensate for resistance drift caused by temperature rise. The online identification process is performed under no-load conditions before each operation begins, by applying a step voltage of known amplitude and recording the steady-state value of the armature current. ,but . This represents a step voltage. The online resistance identification results are used for real-time correction. This ensures the accuracy of feedforward compensation.

[0026] The generation of feedback regulation voltage commands is carried out simultaneously. Motor rotor angular velocity signal. With the target speed set value By comparison, the speed error signal is obtained. The speed error signal is input to the proportional-integral-derivative (PID) controller. The PID controller's parameters are tuned using an adaptive law, dynamically switching control parameters according to the current speed range. The speed range is divided into three segments: a low-speed range of 0 to 800 rpm, a medium-speed range of 800 to 1500 rpm, and a high-speed range of 1500 to 2500 rpm. Each range has independently configured proportional gain, integral time constant, and derivative time constant. For example, in the low-speed range, the proportional gain is smaller to avoid starting shock, and the integral time constant is longer to suppress integral saturation; in the high-speed range, the proportional gain is increased to improve disturbance rejection capability, and the derivative time constant is introduced to suppress high-frequency oscillations. During range switching, the controller uses a linear interpolation smooth transition algorithm, gradually adjusting parameters within 100 milliseconds of crossing the boundary to avoid abrupt changes in the control quantity and ensure system stability.

[0027] The output of the proportional-integral-derivative controller is the feedback regulation voltage command. The feedback adjustment voltage command is the same as the aforementioned feedforward compensation voltage command. The summation is performed in the algebraic superposition unit to form the composite speed regulation voltage command. The feedback regulation voltage represents the optimal armature voltage setting value after comprehensively considering load disturbance feedforward compensation and speed error feedback correction.

[0028] Composite speed control voltage command The signal is then input to the pulse width modulation (PWM) module. This PWM module uses an asymmetric regular sampling method to generate the switching drive signal. The carrier frequency is fixed at 20 kHz to balance switching losses and current ripple. Within each carrier cycle, A high-level active pulse signal is generated by comparing the signal with a triangular carrier wave. To prevent simultaneous conduction of the upper and lower bridge arms in the full-bridge circuit, causing a shoot-through short circuit, the pulse width modulation module inserts a two-microsecond dead time between the high and low-side drive signals. This dead time is implemented through a hardware delay circuit to ensure reliable isolation even under extreme operating conditions. The generated four complementary pulse signals with dead time are then optocoupled and isolated before being sent to the gate drive unit of the power drive circuit.

[0029] The power drive circuit adopts a full-bridge topology, comprising four insulated-gate bipolar transistors (IGBTs), forming the upper and lower bridge arms respectively. Each transistor is equipped with an independent gate drive isolation power supply, ensuring electrical isolation and fast switching capability of the drive signals. Each transistor integrates an overcurrent detection comparator, which monitors the collector current in real time. When the current exceeds 150% of the rated value, the comparator immediately outputs a high-level fault signal. Furthermore, each transistor package embeds a temperature sensor to monitor the junction temperature; when the junction temperature exceeds 125 degrees Celsius, a fault signal is also triggered. Upon detection of any fault signal, the hardware protection circuit immediately blocks all gate drive signals and sends an interrupt request to the industrial controller. The controller then enters a safe shutdown state, records the fault code, and stops operation.

[0030] Before each shearing operation begins, the system automatically executes an online motor parameter identification program. This program runs under no-load conditions on the cutter roller, applying a step voltage excitation with an amplitude of 30% of the rated voltage for 500 milliseconds. During this period, the transient response curves of armature current and rotor angular velocity are acquired at high speed. The acquired data is then fitted using the least squares method to identify the armature resistance. back electromotive force constant and moment of inertia . It is calculated from the steady-state current; Determined by the relationship between steady-state rotational speed and applied voltage; This is obtained by fitting the time constant of the speed increase curve. The identification results are used to update the feedforward gain module. The parameters are adjusted, and the derivative gain term of the proportional-integral-derivative controller is simultaneously corrected to match the dynamic characteristics of the current mechanical system.

[0031] The industrial controller itself is an embedded control unit based on a real-time operating system, with a core processor consisting of a 300 MHz ARM Cortex-R52 core. The system task scheduling cycle is 500 microseconds, comprising four tasks: a data acquisition task responsible for reading raw data from various sensors and preprocessing it; a control algorithm calculation task executing feedforward-feedback composite control logic, including parameter querying, deviation calculation, controller operation, and pulse width modulation instruction generation; a communication task handling data exchange with the human-machine interface and the host computer; and a fault diagnosis task monitoring the status of power devices and system malfunctions. Each task is strictly scheduled according to priority, with the control algorithm calculation task having the highest priority, ensuring timely completion within each scheduling cycle and guaranteeing the determinism and timeliness of the control loop.

[0032] The method also includes a shearing quality feedback correction mechanism. A high-resolution industrial camera is installed above the shearing exit conveyor belt, forming a visual inspection device. This device acquires images of the sheared wool surface at a rate of ten frames per second. After grayscale conversion, filtering, and edge enhancement, the surface roughness index is calculated, defined as the weighted average of the local variance of the image. If the surface roughness index exceeds the preset tolerance band three times consecutively (e.g., the upper limit of the tolerance band is 15, and the lower limit is 5), the shearing quality is deemed unqualified. At this time, the control system automatically fine-tunes the target rotation speed setting value, with an adjustment step of ±5 revolutions per minute. If the roughness is too high, it indicates insufficient shearing force, and the rotation speed needs to be reduced to increase the shearing energy per unit area; if the roughness is too low but accompanied by fiber tension, the rotation speed may be too high and needs to be appropriately increased. Monitoring continues after adjustment until the surface roughness returns to the qualified range, forming a closed-loop optimization system of "perception-decision-execution-verification".

[0033] In summary, this embodiment eliminates intermediate transmission links such as belts and gears, and adopts an integrated direct-drive structure for the motor and cutter roller, completely eliminating energy loss and mechanical backlash in the transmission chain, significantly improving system rigidity and dynamic response speed. The introduction of a feedforward compensation mechanism based on real-time load torque effectively counteracts speed disturbances caused by sudden load changes, shortening speed recovery time. Combined with adaptive proportional-integral-derivative feedback control and target speed setting linked to process parameters, the shearing machine can maintain optimal shearing linear speed under different wool types, humidity levels, and thicknesses. Integrating online parameter identification and visual quality feedback correction, a complete closed-loop optimization system is constructed, significantly improving shearing uniformity, equipment energy efficiency, and long-term operational stability, meeting the stringent requirements of high-precision, high-reliability shearing operations in high-end textile processing.

[0034] 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 process, method, article, or apparatus.

[0035] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A method for speed regulation of a DC motor in a shearing machine based on an industrial control system, characterized in that, include: Acquire real-time load torque signal of the shearing machine's cutter roller, motor rotor angular velocity signal, ambient temperature and humidity data, and current shearing process parameters; Based on the deviation between the real-time load torque signal and the preset reference load threshold, a feedforward compensation voltage command is generated. The motor rotor angular velocity signal is compared with the target speed setpoint to obtain the speed error signal, which is then input to the proportional-integral-derivative controller to output a feedback adjustment voltage command. The feedforward compensation voltage command and the feedback regulation voltage command are algebraically superimposed to form a composite speed regulation voltage command. The composite speed regulation voltage command is converted into a duty cycle adjustable switching drive signal by the pulse width modulation module and applied to the power drive circuit of the DC motor to adjust the motor armature voltage in real time and realize closed-loop speed control.

2. The method for speed regulation of a DC motor in a shearing machine based on an industrial control system according to claim 1, characterized in that, The real-time load torque signal of the shearing machine's cutter roller is obtained through a strain gauge torque sensor installed on the main shaft of the cutter roller. The output signal of the strain gauge torque sensor is processed by an anti-aliasing low-pass filter and then sent to the analog input channel of the industrial controller.

3. The method for speed regulation of a DC motor in a shearing machine based on an industrial control system according to claim 2, characterized in that, The motor rotor angular velocity signal is acquired by an incremental photoelectric encoder. The incremental photoelectric encoder obtains the pulse signal after a 4-fold frequency multiplication through an orthogonal decoding circuit, and calculates the instantaneous angular velocity using a time interval measurement method.

4. The method for speed regulation of a DC motor in a shearing machine based on an industrial control system according to claim 3, characterized in that, The ambient temperature and humidity data are acquired by digital temperature and humidity sensors located within the hair shearing work area.

5. The method for speed regulation of a DC motor in a shearing machine based on an industrial control system according to claim 4, characterized in that, The current shearing process parameters include wool type identification, target shearing length, feed speed setting value, and blade sharpness level. These parameters are input to the industrial controller via a human-machine interface or host computer system interface and stored in non-volatile memory for dynamic adjustment of the target speed setting value.

6. The method for speed regulation of a DC motor in a shearing machine based on an industrial control system according to claim 5, characterized in that, The preset baseline load threshold is dynamically determined based on the current shearing process parameters, and the calculation formula is as follows: ； The baseline load threshold, For the target shear length, For the feed rate, This is the blade sharpness attenuation coefficient. , , These are the process weighting coefficients obtained through offline calibration; Characterizes the inverse proportional effect of shear length on load; It reflects the linear contribution of the feed rate to the load; This demonstrates the additional effect of blade passivation on the load.

7. The method for speed regulation of a DC motor in a shearing machine based on an industrial control system according to claim 6, characterized in that, The process of generating the feedforward compensation voltage command includes: inputting the difference between the real-time load torque signal and the reference load threshold to the feedforward gain module, wherein the gain coefficient of the feedforward gain module is... Determined by the following formula: ； For the armature resistance of a DC motor, The torque constant of the motor. To improve the mechanical efficiency of the integrated motor and cutter roller structure. Updated in real time via an online resistance identification algorithm. and The parameters are calibrated and fixed in the controller parameter library when the equipment leaves the factory.

8. The method for speed regulation of a DC motor in a shearing machine based on an industrial control system according to claim 7, characterized in that, The proportional-integral-derivative controller uses an adaptive law for parameter tuning. The proportional gain, integral time constant, and derivative time constant are dynamically switched according to the current speed range, which is divided into three ranges: low speed, medium speed, and high speed. The parameters of each range are configured independently, and a smooth transition algorithm is used during the switching process to avoid abrupt changes in the control quantity.

9. The method for speed regulation of a DC motor in a shearing machine based on an industrial control system according to claim 8, characterized in that, Before each shearing operation begins, an online motor parameter identification program is executed, including the identification of armature resistance, back electromotive force constant, and moment of inertia. The identification process is carried out under no-load conditions. By applying a step voltage excitation and recording the current and speed response curves, the system transfer function parameters are fitted using the least squares method. The identification results are used to update the feedforward gain module and the controller parameter library.

10. The method for speed regulation of a DC motor in a shearing machine based on an industrial control system according to claim 9, characterized in that, The method also includes a shearing quality feedback correction mechanism: a visual inspection device is set at the shearing exit to collect images of the wool surface after shearing in real time, and the surface roughness index is extracted by the image processing algorithm. If the surface roughness index exceeds the preset tolerance zone three times in a row, the target rotation speed setting value is automatically adjusted until the surface roughness returns to the qualified range.

Images