A coal mining machine dual-motor coupled hybrid cutting system and its control method

Abstract

The present invention provides a dual-motor coupled hybrid cutting system for a coal mining machine and a control method thereof. The system includes an axial flux motor, an active differential, a left electronically controlled clutch, a left cutting motor, a left torque synthesizer, a right electronically controlled clutch, a right cutting motor, a right torque synthesizer, a left sensor group, a right sensor group, and a controller. The method includes controlling the synchronous start-up of the left cutting motor and the right cutting motor; obtaining current data 1 of the left cutting motor and current data 2 of the right cutting motor; judging whether it is overloaded based on the current data, and updating the real-time current error and adaptive gain if overloaded; and dynamically assisting the cutting motor through the engagement or disengagement of the clutch, and dynamically adjusting the distribution of the auxiliary torque. The system and method are highly intelligent and can realize dynamic management and smooth switching of auxiliary power, ensuring that the cutting system can effectively cope with various load-changing working conditions.

Description

Technical Field

[0001] The present invention belongs to the field of intelligent control technology, and in particular relates to a coal mining machine dual-motor coupled hybrid cutting system and a control method thereof. Background Art

[0002] As core equipment in coal mining operations, the performance and efficiency of shearers are directly linked to mine production and safety. Traditional shearer cutting units primarily utilize an electro-hydraulic hybrid drive system. This involves an electric motor driving a hydraulic pump to deliver high-pressure oil, which in turn drives a hydraulic motor, ultimately generating power to rotate the cutting drum. While using hydraulics as an auxiliary power source offers flexibility and controllability, it also presents challenges such as low energy transfer efficiency and system complexity.

[0003] With the increase in the depth of coal mining and the complexity of coal seam conditions, the power and torque requirements for the cutting part of the coal mining machine are also increasing. The use of dual motors as the main power source can provide high power density and precise torque control to meet the operating requirements under complex working conditions. The dual-motor drive has the advantages of fast response speed and high control accuracy. It can flexibly adjust the output under different load conditions to ensure the stable and efficient operation of the cutting part. In addition, through the coordinated work of the dual motors, the dynamic balance of the system load can be achieved, and the overall performance and efficiency of the coal mining machine can be improved. However, in the existing technology, there is a lack of a cutting system and control method that can efficiently integrate the dual-motor drive, which makes the dual-motor driven cutting system in the existing technology unstable. At the same time, the working efficiency needs to be further improved. For this reason, there is an urgent need to provide a new coal mining machine electric-electric hybrid cutting system and its control method. Summary of the Invention

[0004] In response to the problems existing in the above-mentioned prior art, the present invention provides a coal mining machine dual-motor coupled hybrid cutting system and a control method thereof. The system has a reasonable structure, good stability, and a high degree of intelligence. It has a sensitive response speed and can realize dynamic management and smooth switching of auxiliary power, and can ensure that the cutting system can effectively cope with various load-changing working conditions; this method combines the reasonably distributed auxiliary torque with the torque of the cutting motor for output, and can ensure that the coal mining machine can still maintain an efficient and stable working state under complex working conditions.

[0005] To achieve the above-mentioned object, the present invention provides a dual-motor coupled hybrid cutting system for a coal mining machine, comprising an axial flux motor, an active differential, a left electronically controlled clutch, a left cutting motor, a left torque synthesizer, a right electronically controlled clutch, a right cutting motor, a right torque synthesizer, a left sensor group, a right sensor group, and a controller;

[0006] The output shaft of the axial flux motor is connected to the input shaft of the active differential;

[0007] One input end of the left torque synthesizer is connected to the left output shaft of the active differential through the left electronically controlled clutch, and the other input end is connected to the output shaft of the left cutting motor;

[0008] The left electronically controlled clutch includes a left hydraulic clutch, a left electromagnetic reversing valve, a left motor, a left working pressure valve, a left overflow valve and a left hydraulic pump; the left hydraulic clutch includes a left clutch hydraulic cylinder 1 and a left clutch hydraulic cylinder 2; the left motor is coaxially connected to the left hydraulic pump; the oil suction port of the left hydraulic pump is connected to the hydraulic oil tank, and the oil discharge port output of the left hydraulic pump is divided into two paths, one is connected to the P port of the left electromagnetic reversing valve through a pipeline, and the other is connected to the oil inlet of the left working pressure valve; the oil outlet of the left working pressure valve is divided into two paths, one is connected to the rod chamber of the left clutch hydraulic cylinder 1 and the rod chamber of the left clutch hydraulic cylinder 2 respectively, and the other is connected to the hydraulic oil tank through the left overflow valve; the T port of the left electromagnetic reversing valve is connected to the hydraulic oil tank through a pipeline, its A port is connected to the rodless chamber of the left clutch hydraulic cylinder 1 through a pipeline, and its B port is connected to the rodless chamber of the left clutch hydraulic cylinder 2 through a pipeline;

[0009] One input end of the right torque synthesizer is connected to the right output shaft of the active differential through the right electronically controlled clutch, and the other input end is connected to the output shaft of the right cutting motor;

[0010] The right electronically controlled clutch includes a right hydraulic clutch, a right electromagnetic reversing valve, a right motor, a right working pressure valve, a right overflow valve and a right hydraulic pump; the right hydraulic clutch includes a right clutch hydraulic cylinder 1 and a right clutch hydraulic cylinder 2; the right motor is coaxially connected to the right hydraulic pump; the oil suction port of the right hydraulic pump is connected to the hydraulic oil tank, and the oil discharge port output of the right hydraulic pump is divided into two paths, one is connected to the P port of the right electromagnetic reversing valve through a pipeline, and the other is connected to the oil inlet of the right working pressure valve; the oil outlet of the right working pressure valve is divided into two paths, one is respectively connected to the rod chamber of the right clutch hydraulic cylinder 1 and the rod chamber of the right clutch hydraulic cylinder 2, and the other is connected to the hydraulic oil tank through the right overflow valve; the T port of the right electromagnetic reversing valve is connected to the hydraulic oil tank through a pipeline, its A port is connected to the rodless chamber of the right clutch hydraulic cylinder 1 through a pipeline, and its B port is connected to the rodless chamber of the right clutch hydraulic cylinder 2 through a pipeline.

[0011] The left sensor group includes a left current sensor and a left speed sensor; the left current sensor is connected to the left cutting motor and is used to collect the current signal of the left cutting motor in real time; the left speed sensor is connected to the left cutting motor and is used to collect the speed signal of the left cutting motor in real time;

[0012] The right sensor group includes a right current sensor and a right speed sensor; the right current sensor is connected to the right cutting motor and is used to collect the second current signal of the right cutting motor in real time; the right speed sensor is connected to the right cutting motor and is used to collect the second speed signal of the right cutting motor in real time;

[0013] The controller is respectively connected to the left sensor group, the right sensor group, the active differential, the left cutting motor, the left electromagnetic reversing valve, the left motor, the right electromagnetic reversing valve, the right motor and the right cutting motor.

[0014] As a preference, the controller is a PLC controller.

[0015] As a preferred embodiment, the left solenoid reversing valve and the right solenoid reversing valve are both three-position four-way solenoid reversing valves. When they are working in the left position, the oil circuit between their P port and A port is connected, and the oil circuit between their T port and B port is connected. When they are working in the middle position, their P port is cut off, and their T port, A port and B port are connected to each other. When they are working in the right position, the oil circuit between their P port and B port is connected, and the oil circuit between their T port and A port is connected.

[0016] In the present invention, the output shaft of the axial flux motor is connected to the input shaft of the active differential, and the left and right output shafts of the active differential are then directed to the left and right cutting systems, respectively, to provide additional driving force for the left and right cutting systems. Due to the advantages of the axial flux motor, such as compact structure, high power density, and high efficiency, it is suitable for providing stable driving force within limited spaces. Thus, by adding the axial flux motor, a stable additional driving force can be provided to the cutting system, effectively addressing situations where the left and right cutting motors are overloaded, ensuring stable and reliable cutting operations of the coal shearer and improving coal mining efficiency. The single-sided output shaft of the active differential is connected to one input of a single-sided torque combiner via a single-sided electronically controlled clutch. Simultaneously, the other input of the single-sided torque combiner is connected to the output shaft of the single-sided cutting motor. This allows the single-sided torque combiner to efficiently couple the output of the single-sided cutting motor with the single-sided output of the active differential. The coupled total output can then be used to efficiently drive the single-sided cutting drum for cutting operations. Simultaneously, the engagement and disengagement of the single-sided electronically controlled clutch can be controlled by controlling the single-sided electromagnetic reversing valve. This allows for convenient control of the engagement and disengagement of additional driving force based on load requirements, enabling dynamic management and smooth switching of auxiliary power, ensuring that the cutting system can effectively cope with various load-variable operating conditions. The single-sided hydraulic clutch is equipped with both clutch cylinders one and two, each connected to ports A and B of the one-way electromagnetic reversing valve, respectively. This ensures that if one clutch cylinder fails, the other clutch cylinder can still be used to ensure normal clutch operation, thus ensuring clutch stability and reliability. By installing a speed sensor and a current sensor on the cutting motor on one side respectively, the speed signal and current signal of the cutting motor on one side can be collected in real time, and then the speed data and current data of the left cutting motor can be obtained. In this way, not only can the error be updated according to the load condition of the cutting motor, and the controller on the corresponding side can be adaptively gain-adjusted to ensure that the power output can follow the load changes in real time, but also the controller can obtain the auxiliary torque required by the cutting motor on one side in real time, and then the auxiliary torque can be provided by controlling the engagement and disengagement of the electronically controlled clutch on the corresponding side to meet the requirements of the load condition. Furthermore, the distribution ratio of the auxiliary torque can be adjusted by calculating the speed difference between the left and right cutting motors to effectively balance the speed and load of the left and right cutting motors.

[0017] The system has a reasonable structure, good stability, and a high degree of intelligence. It has a sensitive response speed and can realize dynamic management and smooth switching of auxiliary power, ensuring that the cutting system can effectively cope with various load changes. While reducing energy consumption, it effectively extends the service life of the coal mining machine.

[0018] The present invention also provides a control method for a dual-motor coupled hybrid cutting system for a coal mining machine, which uses a dual-motor coupled hybrid cutting system for a coal mining machine, comprising the following steps:

[0019] Step 1: When the coal shearer starts to perform coal mining operations, the left cutting motor and the right cutting motor are controlled to start working synchronously, so that the coal shearer enters a normal coal seam cutting working mode;

[0020] Step 2: The left current sensor collects the current signal 1 of the left cutting motor in real time and sends it to the controller; the left speed sensor collects the speed signal 1 of the left cutting motor in real time and sends it to the controller; the right current sensor collects the current signal 2 of the right cutting motor in real time and sends it to the controller; the right speed sensor collects the speed signal 2 of the right cutting motor in real time and sends it to the controller;

[0021] The controller obtains the current data of the left cutting motor I according to the received current signal I and speed signal I 左 (t) and speed data -ω 左 (t), and then sense the load state of the left cutting motor in real time; the controller obtains the current data I of the right cutting motor according to the received current signal II and speed signal II 右 (t) and speed data ω 右 (t), and then sense the load status of the right cutting motor in real time;

[0022] Step 3: If the current data of the left cutting motor is I 左 (t) is greater than or equal to the overload current threshold I 阈值左 And the overload duration t 持续左 Greater than or equal to the duration threshold T 延时 , the left cutting motor is determined to be overloaded, and step 4 is directly executed to enter the left cutting motor error update and adaptive gain adjustment process. Otherwise, the left electromagnetic reversing valve is controlled to work in the neutral position unchanged, so that the left hydraulic clutch is disengaged;

[0023] If the current data of the right cutting motor is I 右 (t) is greater than or equal to the overload current threshold I 阈值右 And the overload duration t 持续右 Greater than or equal to the duration threshold T 延时 , the right cutting motor is determined to be overloaded, and step 4 is directly executed to enter the right cutting motor error update and adaptive gain adjustment process. Otherwise, the right electromagnetic reversing valve is controlled to work in the neutral position unchanged, so that the right hydraulic clutch is disengaged;

[0024] Step 4: Update the real-time current error e(t) according to the motor load on the overload side, and adjust the control parameters on the overload side by adaptive gain θ(t) to ensure that the power output on the overload side can follow the load changes on the overload side in real time;

[0025] S41: Obtain the real-time current error e(t) of the overload side motor according to formula (1), and perform error update according to the real-time current error e(t);

[0026] e(t)=I 实际 (t)-I 额定 (1);

[0027] Where, I 实际 (t) is the actual current at the current moment, I 额定 is the rated current of the motor;

[0028] S42: Define the Lyapunov function according to formula (2);

[0029]

[0030] Where θ * is the ideal parameter value, γ>0 is the adaptation rate;

[0031] S43: Derivative the formula (2) to obtain the time rate of change of the Lyapunov function as shown in formula (3). At the same time,

[0032]

[0033] Where, is the adaptive parameter update law;

[0034] S44: Calculate according to formula (4) and use Update the adaptive gain θ(t);

[0035]

[0036] Where, is the regression vector;

[0037] S45: discretizing the adaptive gain using the Euler forward difference method according to formula (5);

[0038]

[0039] S46: setting the upper and lower limits of the adaptive gain θ(t) according to formula (6). When θ(t) exceeds the limit value, saturation processing is performed to prevent the cutting system from becoming unstable.

[0040] 0≤θ(t)≤θ max (6);

[0041] Step 5: Calculate the auxiliary torque on the overload side according to the real-time load on the overload side and obtain the required total input torque;

[0042] S51: Calculate the unilateral assist torque M using the updated adaptive gain θ(t) and the real-time current error e(t) according to formula (7) 辅助单侧 (t);

[0043] M 辅助单侧 (t) = -θ(t)·e(t) (7);

[0044] S52: Assist torque M according to formula (8) 辅助 (t) clipping processing;

[0045] 0≤M 辅助 (t)≤M 辅助max (8);

[0046] S53: Use a first-order low-pass filter to filter the auxiliary torque M 辅助单侧 (t) is smoothed, and the smoothed assist torque M is obtained according to formula (9): 辅助滤波单侧 (t);

[0047] M 辅助滤波单侧 (t) = α·M 辅助单侧 (t)+(1-α)·M 辅助单侧 (t-Δt) (9);

[0048] S54: According to formula (10), the smoothed assist torques on the left and right sides are added together to obtain the required total input torque M 总输入 ;

[0049] M 总输入 =M 辅助滤波左 +M 辅助滤波右 (10);

[0050] Step 6: Control the engagement and disengagement of the electronically controlled clutch through the electronically controlled reversing valve to combine the auxiliary power with the output power of the cutting motor according to actual conditions, thereby achieving dynamic assistance to the cutting motor;

[0051] S61: Control the axial flux motor to start working and make the torque input to the active differential by the axial flux motor be M 总输入 ;

[0052] When the M on the corresponding side 辅助滤波When (t)>0, the controller controls the left motor to drive the left hydraulic pump to work, uses the oil discharge port of the left hydraulic pump to output high-pressure oil, and controls the left electromagnetic reversing valve to work in the left position or the right position, so that the left hydraulic clutch is engaged, and the auxiliary power output by the left output shaft of the active differential is input to one input end of the left torque synthesizer, and after the coupling effect of the left torque synthesizer and the power output by the left cutting motor are merged, the left cutting drum is driven to perform cutting operation. Synchronously, the right motor is controlled to drive the right hydraulic pump to work, uses the oil discharge port of the right hydraulic pump to output high-pressure oil, and controls the right electromagnetic reversing valve to work in the left position or the right position accordingly, so that the right hydraulic clutch is engaged, and the auxiliary power output by the right output shaft of the active differential is input to one input end of the right torque synthesizer, and after the coupling effect of the right torque synthesizer and the power output by the right cutting motor are merged, the left cutting drum is driven to perform cutting operation.

[0053] Synchronously, the output torque of the left cutting motor and the output torque of the right cutting motor are dynamically adjusted according to the distributed torque of the left cutting motor and the distributed torque of the right cutting motor, so that the speed of the cutting motor matches its load state. The specific process is as follows:

[0054] A1: Get the speed data of the left cutting motor in real time 左 (t) and the speed data of the right cutting motor ω 右 (t), and calculate the speed difference Δω(t) between the left cutting motor and the right cutting motor according to formula (11), and set the threshold ω by combining Δω(t) with the speed difference 阈值 For comparison, if |Δω(t)|>ω 阈值 , then execute A2, otherwise, the control keeps the output state of the active differential unchanged and directly executes A3;

[0055] Δω(t)=ω 左 (t)-ω 右 (t) (11);

[0056] A2: According to formula (12), the torque M required to be distributed to the left cutting motor is obtained. 输出分配左 (t), and then according to formula (13) to obtain the torque M required to be distributed to the right cutting motor 输出分配右 (t), the output torque of the left output shaft of the active differential is controlled to be M 输出分配左 (t), in order to balance the output of the left cutting motor, make the speed of the left cutting motor and its load tend to be consistent, and control the output torque of the right output shaft of the active differential to be M 输出分配右 (t) to balance the output of the right cutting motor so that the speed of the right cutting motor and its load tend to be consistent;

[0057]

[0058] M 输出分配右(t) = M 总输入 -M 输出分配左 (t) (13);

[0059] A3: According to the speed data of the left cutting motor 左 (t) Calculate the output torque M of the left cutting motor 电机左 (t), and then according to formula (14) the total output torque M on the left side is obtained 总左 (t), and for M 总左 (t) Perform kinetic analysis to ensure that M 总左 (t) not exceeding the load capacity of the left mechanical structure and the left cutting motor; according to the speed data of the right cutting motor 右 (t) Calculate the output torque M of the right cutting motor 电机右 (t), and then according to formula (15) the total output torque M on the right side is obtained 总右 (t), and M 总右 (t) Perform kinetic analysis to ensure that M 总右 (t) Exceeding the load capacity of the right mechanical structure and the right cutting motor

[0060] M 总左 (t) = M 电机左 (t)+M 输出分配左 (t) (14);

[0061] M 总右 (t) = M 电机右 (t)+M 输出分配右 (t) (15);

[0062] When M 辅助滤波 (t) When the pressure drops to zero or the overload condition is released, the left electromagnetic reversing valve is controlled to operate in the neutral position to disengage the left hydraulic clutch. At the same time, the right electromagnetic reversing valve is controlled to operate in the neutral position to disengage the right hydraulic clutch, disconnecting the auxiliary torque output by the active differential and stopping the transmission of the auxiliary power;

[0063] Step 7: Repeat steps 2 to 6 to dynamically adjust the distribution of the auxiliary torque.

[0064] In order to ensure the balance of the initial working state, in step 1, the starting parameters of the left cutting motor and the right cutting motor are controlled to be completely consistent.

[0065] As a preferred embodiment, in step 2, the overload current threshold I is obtained according to formula (16): 阈值左 , according to formula (17) to obtain the overload current threshold I 阈值右 ;

[0066] I 阈值左 =K 过载 ×I 额定左(16);

[0067] I 阈值右 =K 过载 ×I 额定右 (17);

[0068] Where K 过载 is the overload coefficient, which is 1.2; I 额定左 is the rated current of the left cutting motor, which is 0.5. 额定右 is the rated current of the right cutting motor, which is 0.5;

[0069] Furthermore, in order to accurately control the action of the solenoid reversing valve and make the action process of the solenoid reversing valve more stable, in step six, the controller uses PWM to control the action of the left solenoid reversing valve and the right solenoid reversing valve to ensure the smoothness and reliability of the reversing process of the left solenoid reversing valve and the right solenoid reversing valve.

[0070] The present invention proposes a new driving method for the electric-electric hybrid cutting part of a coal mining machine. First, it uses a current sensor to collect the current signal of the cutting motor in real time to obtain current data, and then compares the current data with the overload current threshold. When the current data exceeds the overload current threshold and reaches the overload duration, it determines that an overload has occurred, and then performs an error update and adaptive gain adjustment process. Through error update and adaptive gain adjustment, it can effectively ensure that the power output of the overload side can follow the changes in the overload side load in real time, thereby significantly improving the control accuracy and response speed, which is conducive to the subsequent accurate distribution of auxiliary power. Secondly, it calculates the required auxiliary torque based on the updated adaptive gain and current error, and can obtain the auxiliary torque required on one side. Then, through first-order filtering, the required auxiliary torque can be further accurately determined. On this basis, the auxiliary torque required on both sides is added together to accurately determine the torque required to be input by the axial flux motor. In M 辅助滤波 When (t)>0, the electromagnetic reversing valve is controlled to switch to the engagement chamber and gradually engage the hydraulic clutch, thereby transmitting the auxiliary power output by the active differential to the cutting motor. The active differential and the hydraulic clutch work together to ensure that the torque distribution between the left and right cutting motors is always optimal under different load conditions. When the auxiliary torque drops to zero or the overload condition is removed, the electromagnetic reversing valve switches to the disengagement chamber, and the hydraulic clutch is immediately disconnected, stopping the transmission of auxiliary power. This process effectively avoids mechanical shock and ensures smooth operation of the cutting system. During the hydraulic clutch engagement process, the active differential is controlled by the speed of the left and right cutting motors to dynamically distribute the auxiliary torque, making the torque adjustment process more flexible, effectively ensuring that the cutting motor speed matches its load, and thus ensuring the efficient operation of the coal mining machine. At the same time, it effectively protects the cutting motor, which helps to extend the overall service life of the coal mining machine.

[0071] This method combines the reasonably distributed auxiliary torque with the torque of the cutting motor for output, which can ensure that the coal mining machine can still maintain an efficient and stable working state under complex working conditions. At the same time, it can realize dynamic management and smooth switching of auxiliary power, ensuring that the cutting system can effectively cope with various load changes. It is beneficial to reduce the maintenance cost of the coal mining machine and greatly improve the working efficiency and reliability of the coal mining machine. It has important practical significance and application value for promoting the advancement of coal mining technology. BRIEF DESCRIPTION OF THE DRAWINGS

[0072] Figure 1 It is a principle block diagram of the cutting system in the present invention;

[0073] Figure 2 is a flow chart of the control method of the present invention;

[0074] Figure 3 It is a structural diagram of the cutting system in the present invention.

[0075] In the figure: 1. axial flux motor, 2. active differential, 3. left electronically controlled clutch, 4. right electronically controlled clutch, 5. left torque synthesizer, 6. right torque synthesizer, 7. left cutting motor, 8. right cutting motor, 9. left motor, 10. left hydraulic pump, 11. left electromagnetic reversing valve, 12. left hydraulic clutch, 13. left clutch hydraulic cylinder one, 14. left clutch hydraulic cylinder two, 15. left working pressure valve, 16. left overflow valve, 17. hydraulic oil tank, 18. right motor, 19. right hydraulic pump, 20. right electromagnetic reversing valve, 21. right hydraulic clutch, 22. right clutch hydraulic cylinder one, 23. right clutch hydraulic cylinder two, 24. right working pressure valve, 25. right overflow valve. DETAILED DESCRIPTION

[0076] The present invention will be further described below with reference to the accompanying drawings.

[0077] like Figure 1 and Figure 3 As shown, the present invention provides a dual-motor coupled hybrid cutting system for a coal mining machine, comprising an axial flux motor 1, an active differential 2, a left electronically controlled clutch 3, a left cutting motor 7, a left torque synthesizer 5, a right electronically controlled clutch 4, a right cutting motor 8, a right torque synthesizer 6, a left sensor group, a right sensor group, and a controller;

[0078] As a preferred embodiment, the axial flux motor 1 can be installed on a reduction gearbox;

[0079] The output shaft of the axial flux motor 1 is connected to the input shaft of the active differential 2;

[0080] One input end of the left torque synthesizer 5 is connected to the left output shaft of the active differential 2 through the left electronically controlled clutch 3, and the other input end is connected to the output shaft of the left cutting motor 7;

[0081] The left electronically controlled clutch 3 includes a left hydraulic clutch 12, a left electromagnetic reversing valve 11, a left motor 9, a left working pressure valve 15, a left overflow valve 16 and a left hydraulic pump 10; the left hydraulic clutch 12 includes a left clutch hydraulic cylinder 13 and a left clutch hydraulic cylinder 2 14; the left motor 9 is coaxially connected to the left hydraulic pump 10; the oil suction port of the left hydraulic pump 10 is connected to the hydraulic oil tank 17, and the oil discharge port output of the left hydraulic pump 10 is divided into two paths, one of which is connected to the P port of the left electromagnetic reversing valve 11 through a pipeline, and the other is connected to the P port of the left electromagnetic reversing valve 11 through a pipeline. The oil outlet of the left working pressure valve 15 is connected to the oil inlet of the left working pressure valve 15; the oil outlet of the left working pressure valve 15 is divided into two routes, one of which is connected to the rod chamber of the left clutch hydraulic cylinder 13 and the rod chamber of the left clutch hydraulic cylinder 2 14 respectively, and the other is connected to the hydraulic oil tank 17 through the left relief valve 16; the T port of the left solenoid reversing valve 11 is connected to the hydraulic oil tank 17 through a pipeline, its A port is connected to the rodless chamber of the left clutch hydraulic cylinder 13 through a pipeline, and its B port is connected to the rodless chamber of the left clutch hydraulic cylinder 2 14 through a pipeline;

[0082] One input end of the right torque synthesizer 6 is connected to the right output shaft of the active differential 2 through the right electronically controlled clutch 4, and the other input end is connected to the output shaft of the right cutting motor 8;

[0083] The right electronically controlled clutch 4 includes a right hydraulic clutch 21, a right electromagnetic reversing valve 20, a right motor 18, a right working pressure valve 24, a right overflow valve 25 and a right hydraulic pump 19; the right hydraulic clutch 21 includes a right clutch hydraulic cylinder 1 22 and a right clutch hydraulic cylinder 2 23; the right motor 18 is coaxially connected to the right hydraulic pump 19; the oil suction port of the right hydraulic pump 19 is connected to the hydraulic oil tank 17, and the oil discharge port output of the right hydraulic pump 19 is divided into two paths, one of which is connected to the P port of the right electromagnetic reversing valve 20 through a pipeline, and the other is connected to the P port of the right electromagnetic reversing valve 20 through a pipeline. One path is connected to the oil inlet of the right working pressure valve 24; the oil outlet of the right working pressure valve 24 is divided into two paths, one path is connected to the rod chamber of the right clutch hydraulic cylinder 1 22 and the rod chamber of the right clutch hydraulic cylinder 2 23 respectively, and the other path is connected to the hydraulic oil tank 17 through the right overflow valve 25; the T port of the right electromagnetic reversing valve 20 is connected to the hydraulic oil tank 17 through a pipeline, its A port is connected to the rodless chamber of the right clutch hydraulic cylinder 1 22 through a pipeline, and its B port is connected to the rodless chamber of the right clutch hydraulic cylinder 2 23 through a pipeline.

[0084] The left sensor group includes a left current sensor and a left speed sensor; the left current sensor is connected to the left cutting motor 7 and is used to collect the current signal of the left cutting motor 7 in real time; the left speed sensor is connected to the left cutting motor 7 and is used to collect the speed signal of the left cutting motor 7 in real time;

[0085] The right sensor group includes a right current sensor and a right speed sensor; the right current sensor is connected to the right cutting motor 8 and is used to collect the second current signal of the right cutting motor 8 in real time; the right speed sensor is connected to the right cutting motor 8 and is used to collect the second speed signal of the right cutting motor 8 in real time;

[0086] As a preferred method, the sampling frequency of the left sensor group and the right sensor group is set to 1000Hz to meet the real-time requirements of the control. The analog signals collected by the sensors are sequentially filtered and anti-interference processed to ensure the accuracy and stability of the signals, which helps the controller obtain accurate monitoring data.

[0087] The controller is respectively connected to the left sensor group, the right sensor group, the active differential 2, the left cutting motor 7, the left electromagnetic reversing valve 11, the left motor 9, the right electromagnetic reversing valve 20, the right motor 18 and the right cutting motor 8.

[0088] As a preference, the controller is a PLC controller.

[0089] As a preferred embodiment, the left solenoid reversing valve 11 and the right solenoid reversing valve 20 are both three-position four-way solenoid reversing valves. When they are working in the left position, the oil circuit between their P port and A port is connected, and the oil circuit between their T port and B port is connected. When they are working in the middle position, their P port is cut off, and their T port, A port and B port are connected to each other. When they are working in the right position, the oil circuit between their P port and B port is connected, and the oil circuit between their T port and A port is connected.

[0090] In the present invention, the output shaft of the axial flux motor is connected to the input shaft of the active differential, and the left and right output shafts of the active differential are then directed to the left and right cutting systems, respectively, to provide additional driving force for the left and right cutting systems. Due to the advantages of the axial flux motor, such as compact structure, high power density, and high efficiency, it is suitable for providing stable driving force within limited spaces. Thus, by adding the axial flux motor, a stable additional driving force can be provided to the cutting system, effectively addressing situations where the left and right cutting motors are overloaded, ensuring stable and reliable cutting operations of the coal shearer and improving coal mining efficiency. The single-sided output shaft of the active differential is connected to one input of a single-sided torque combiner via a single-sided electronically controlled clutch. Simultaneously, the other input of the single-sided torque combiner is connected to the output shaft of the single-sided cutting motor. This allows the single-sided torque combiner to efficiently couple the output of the single-sided cutting motor with the single-sided output of the active differential. The coupled total output can then be used to efficiently drive the single-sided cutting drum for cutting operations. Simultaneously, the engagement and disengagement of the single-sided electronically controlled clutch can be controlled by controlling the single-sided electromagnetic reversing valve. This allows for convenient control of the engagement and disengagement of additional driving force based on load requirements, enabling dynamic management and smooth switching of auxiliary power, ensuring that the cutting system can effectively cope with various load-variable operating conditions. The single-sided hydraulic clutch is equipped with both clutch cylinders one and two, each connected to ports A and B of the one-way electromagnetic reversing valve, respectively. This ensures that if one clutch cylinder fails, the other clutch cylinder can still be used to ensure normal clutch operation, thus ensuring clutch stability and reliability. By installing a speed sensor and a current sensor on the cutting motor on one side respectively, the speed signal and current signal of the cutting motor on one side can be collected in real time, and then the speed data and current data of the left cutting motor can be obtained. In this way, not only can the error be updated according to the load condition of the cutting motor, and the controller on the corresponding side can be adaptively gain-adjusted to ensure that the power output can follow the load changes in real time, but also the controller can obtain the auxiliary torque required by the cutting motor on one side in real time, and then the auxiliary torque can be provided by controlling the engagement and disengagement of the electronically controlled clutch on the corresponding side to meet the requirements of the load condition. Furthermore, the distribution ratio of the auxiliary torque can be adjusted by calculating the speed difference between the left and right cutting motors to effectively balance the speed and load of the left and right cutting motors.

[0091] The system has a reasonable structure, good stability, and a high degree of intelligence. It has a sensitive response speed and can realize dynamic management and smooth switching of auxiliary power, ensuring that the cutting system can effectively cope with various load changes. While reducing energy consumption, it effectively extends the service life of the coal mining machine.

[0092] like Figure 2 As shown, the present invention also provides a control method for a coal mining machine dual-motor coupled hybrid cutting system, which adopts a coal mining machine dual-motor coupled hybrid cutting system, including the following steps:

[0093] Step 1: When the coal shearer starts to perform coal mining operations, the left cutting motor 7 and the right cutting motor 8 are controlled to start working synchronously, so that the coal shearer enters a normal coal seam cutting working mode;

[0094] Step 2: The left current sensor collects the current signal 1 of the left cutting motor 7 in real time and sends it to the controller; the left speed sensor collects the speed signal 1 of the left cutting motor 7 in real time and sends it to the controller; the right current sensor collects the current signal 2 of the right cutting motor 8 in real time and sends it to the controller; the right speed sensor collects the speed signal 2 of the right cutting motor 8 in real time and sends it to the controller;

[0095] The controller obtains the current data I of the left cutting motor 7 according to the received current signal I and speed signal I. 左 (t) and speed data -ω 左 (t), and then real-time perception of the load state of the left cutting motor 7; the controller obtains the current data I of the right cutting motor 8 according to the received current signal II and speed signal II 右 (t) and speed data ω 右 (t), and then sense the load state of the right cutting motor 8 in real time;

[0096] Step 3: If the current data of the left cutting motor 7 is I 左 (t) is greater than or equal to the overload current threshold I 阈值左 And the overload duration t 持续左 Greater than or equal to the duration threshold T 延时 , it is determined that the left cutting motor 7 is overloaded, and step 4 is directly executed to enter the error update and adaptive gain adjustment process of the left cutting motor 7. Otherwise, the left electromagnetic reversing valve 11 is controlled to work in the neutral position unchanged, so that the left hydraulic clutch 12 is disengaged;

[0097] If the current data of the right cutting motor 8 is equal to I 右 (t) is greater than or equal to the overload current threshold I 阈值右 And the overload duration t 持续右 Greater than or equal to the duration threshold T 延时 , it is determined that the right cutting motor 8 is overloaded, and step 4 is directly executed to enter the error update and adaptive gain adjustment process of the right cutting motor 8. Otherwise, the right electromagnetic reversing valve 20 is controlled to work in the neutral position unchanged, so that the right hydraulic clutch 21 is disengaged;

[0098] Step 4: Update the real-time current error e(t) according to the motor load on the overload side, and adjust the control parameters on the overload side by adaptive gain θ(t) to ensure that the power output on the overload side can follow the load changes on the overload side in real time;

[0099] S41: Obtain the real-time current error e(t) of the overload side motor according to formula (1), and perform error update according to the real-time current error e(t);

[0100] e(t)=I 实际 (t)-I 额定 (1);

[0101] Where, I 实际 (t) is the actual current at the current moment, I 额定 is the rated current of the motor;

[0102] S42: Define the Lyapunov function according to formula (2);

[0103]

[0104] Where θ * is the ideal parameter value, γ>0 is the adaptation rate;

[0105] S43: Derivative the formula (2) to obtain the time rate of change of the Lyapunov function as shown in formula (3). At the same time,

[0106]

[0107] Where, is the adaptive parameter update law;

[0108] S44: Calculate according to formula (4) and use Update the adaptive gain θ(t);

[0109]

[0110] Where, is the regression vector;

[0111] S45: discretizing the adaptive gain using the Euler forward difference method according to formula (5);

[0112]

[0113] S46: setting the upper and lower limits of the adaptive gain θ(t) according to formula (6). When θ(t) exceeds the limit value, saturation processing is performed to prevent the cutting system from becoming unstable.

[0114] 0≤θ(t)≤θ max (6);

[0115] Step 5: Calculate the auxiliary torque on the overload side according to the real-time load on the overload side and obtain the required total input torque;

[0116] S51: Calculate the unilateral assist torque M using the updated adaptive gain θ(t) and the real-time current error e(t) according to formula (7) 辅助单侧 (t);;

[0117] M 辅助单侧 (t) = -θ(t)·e(t) (7);

[0118] S52: To prevent the control input from being too large, torque limiting is performed and the auxiliary torque M is calculated according to formula (8). 辅助 (t) clipping processing;

[0119] 0≤M 辅助 (t)≤M 辅助max (8);

[0120] S53: Use a first-order low-pass filter to filter the auxiliary torque M 辅助单侧 (t) is smoothed, and the smoothed assist torque M is obtained according to formula (9): 辅助滤波单侧 (t);

[0121] M 辅助滤波单侧 (t) = α·M 辅助单侧 (t)+(1-α)·M 辅助单侧 (t-Δt) (9);

[0122] S54: According to formula (10), the smoothed assist torques on the left and right sides are added together to obtain the required total input torque M 总输入 ;

[0123] M 总输入 =M 辅助滤波左 +M 辅助滤波右 (10);

[0124] Among them, M 辅助滤波左 and M 辅助滤波右 All are calculated by formula (9);

[0125] Step 6: Control the engagement and disengagement of the electronically controlled clutch through the electronically controlled reversing valve to combine the auxiliary power with the output power of the cutting motor according to actual conditions, thereby achieving dynamic assistance to the cutting motor;

[0126] S61: Control the axial flux motor 1 to start working and make the torque input to the active differential 2 by the axial flux motor 1 be M 总输入; When the M on the corresponding side 辅助滤波 When (t)>0, the controller controls the left motor 9 to drive the left hydraulic pump 10 to work, uses the oil discharge port of the left hydraulic pump 10 to output high-pressure oil, and controls the left electromagnetic reversing valve 11 to work in the left position or the right position, so that the left hydraulic clutch 12 is engaged, and the auxiliary power output by the left output shaft of the active differential 2 is input to one input end of the left torque synthesizer 5, and after the coupling effect of the left torque synthesizer 5 and the power output by the left cutting motor 7 are merged, the left cutting drum is driven to perform the cutting operation. Synchronously, the controller controls the right motor 18 to drive the right hydraulic pump 19 to work, uses the oil discharge port of the right hydraulic pump 19 to output high-pressure oil, and controls the right electromagnetic reversing valve 20 to work in the left position or the right position accordingly, so that the right hydraulic clutch 21 is engaged, and the auxiliary power output by the right output shaft of the active differential 2 is input to one input end of the right torque synthesizer 6, and after the coupling effect of the right torque synthesizer 6 and the power output by the right cutting motor 8 are merged, the left cutting drum is driven to perform the cutting operation.

[0127] Synchronously, the output torque of the left cutting motor 7 and the output torque of the right cutting motor 8 are dynamically adjusted according to the distributed torque of the left cutting motor 7 and the distributed torque of the right cutting motor 8, so that the speed of the cutting motor matches its load state. The specific process is as follows:

[0128] A1: Real-time acquisition of the speed data of the left cutting motor 7 左 (t) and the speed data of the right cutting motor 8 右 (t), and calculate the speed difference Δω(t) between the left cutting motor 7 and the right cutting motor 8 according to formula (11), and set the threshold ω by combining Δω(t) with the speed difference 阈值 For comparison, if |Δω(t)|>ω 阈值 , then execute A2, otherwise, the control keeps the output state of the active differential 2 unchanged and directly executes A3;

[0129] Δω(t)=ω 左 (t)-ω 右 (t) (11);

[0130] A2: According to formula (12), the torque M required to be distributed to the left cutting motor 7 is obtained. 输出分配左 (t), and then according to formula (13) the torque M required to be distributed to the right cutting motor 8 is obtained 输出分配右 (t), control the output torque of the left output shaft of the active differential 2 to be M 输出分配左 (t), in order to balance the output of the left cutting motor 7, so that the speed of the left cutting motor 7 and its load tend to be consistent, and control the output torque of the right output shaft of the active differential 2 to be M 输出分配右 (t) to balance the output of the right cutting motor 8 so that the speed of the right cutting motor 8 and its load tend to be consistent;

[0131]

[0132] M 输出分配右 (t) = M 总输入 -M 输出分配左 (t) (13);

[0133] A3: According to the speed data of the left cutting motor 7 左 (t) Calculate the output torque M of the left cutting motor 7 电机左 (t), and then according to formula (14) the total output torque M on the left side is obtained 总左 (t), and for M 总左 (t) Perform kinetic analysis to ensure that M 总左 (t) does not exceed the load capacity of the left mechanical structure and the left cutting motor 7; according to the speed data of the right cutting motor 8 右 (t) Calculate the output torque M of the right cutting motor 8 电机右 (t), and then according to formula (15) the total output torque M on the right side is obtained 总右 (t), and M 总右 (t) Perform kinetic analysis to ensure that M 总右 (t) Exceeding the load capacity of the right mechanical structure and the right cutting motor 8

[0134] M 总左 (t) = M 电机左 (t)+M 输出分配左 (t) (14);

[0135] M 总右 (t) = M 电机右 (t)+M 输出分配右 (t) (15);

[0136] When M 辅助滤波 (t) When the pressure drops to zero or the overload state is released, the left electromagnetic reversing valve 11 is controlled to operate in the neutral position, so that the left hydraulic clutch 12 is disengaged. At the same time, the right electromagnetic reversing valve 20 is controlled to operate in the neutral position, so that the right hydraulic clutch 21 is disengaged, the auxiliary torque output by the active differential 2 is disconnected, and the transmission process of the auxiliary power is stopped;

[0137] Step 7: Repeat steps 2 to 6 to dynamically adjust the distribution of the auxiliary torque.

[0138] In order to ensure the balance of the initial working state, in step 1, the starting parameters of the left cutting motor 7 and the right cutting motor 8 are controlled to be completely consistent.

[0139] As a preferred embodiment, in step 2, the overload current threshold I is obtained according to formula (16): 阈值左 , according to formula (17) to obtain the overload current threshold I阈值右 ;

[0140] I 阈值左 =K 过载 ×I 额定左 (16);

[0141] I 阈值右 =K 过载 ×I 额定右 (17);

[0142] Where K 过载 is the overload coefficient, which is 1.2; I 额定左 is the rated current of the left cutting motor 7, which is 0.5, I 额定右 is the rated current of the right cutting motor 8, which is 0.5;

[0143] In order to accurately control the action of the solenoid reversing valve and make the action process of the solenoid reversing valve more stable, in step six, the controller uses PWM to control the action of the left solenoid reversing valve 11 and the right solenoid reversing valve 20 to ensure the smoothness and reliability of the reversing process of the left solenoid reversing valve 11 and the right solenoid reversing valve 20.

[0144] The present invention proposes a new driving method for the electric-electric hybrid cutting part of a coal mining machine. First, it uses a current sensor to collect the current signal of the cutting motor in real time to obtain current data, and then compares the current data with the overload current threshold. When the current data exceeds the overload current threshold and reaches the overload duration, it determines that an overload has occurred, and then performs an error update and adaptive gain adjustment process. Through error update and adaptive gain adjustment, it can effectively ensure that the power output of the overload side can follow the changes in the overload side load in real time, thereby significantly improving the control accuracy and response speed, which is conducive to the subsequent accurate distribution of auxiliary power. Secondly, it calculates the required auxiliary torque based on the updated adaptive gain and current error, and can obtain the auxiliary torque required on one side. Then, through first-order filtering, the required auxiliary torque can be further accurately determined. On this basis, the auxiliary torque required on both sides is added together to accurately determine the torque required to be input by the axial flux motor. In M 辅助滤波When (t)>0, the electromagnetic reversing valve is controlled to switch to the engagement chamber and gradually engage the hydraulic clutch, thereby transmitting the auxiliary power output by the active differential to the cutting motor. The active differential and the hydraulic clutch work together to ensure that the torque distribution between the left and right cutting motors is always optimal under different load conditions. When the auxiliary torque drops to zero or the overload condition is removed, the electromagnetic reversing valve switches to the disengagement chamber, and the hydraulic clutch is immediately disconnected, stopping the transmission of auxiliary power. This process effectively avoids mechanical shock and ensures smooth operation of the cutting system. During the hydraulic clutch engagement process, the active differential is controlled by the speed of the left and right cutting motors to dynamically distribute the auxiliary torque, making the torque adjustment process more flexible, effectively ensuring that the cutting motor speed matches its load, and thus ensuring the efficient operation of the coal mining machine. At the same time, it effectively protects the cutting motor, which helps to extend the overall service life of the coal mining machine.

[0145] This method combines the reasonably distributed auxiliary torque with the torque of the cutting motor for output, which can ensure that the coal mining machine can still maintain an efficient and stable working state under complex working conditions. At the same time, it can realize dynamic management and smooth switching of auxiliary power, ensuring that the cutting system can effectively cope with various load changes. It is beneficial to reduce the maintenance cost of the coal mining machine and greatly improve the working efficiency and reliability of the coal mining machine. It has important practical significance and application value for promoting the advancement of coal mining technology.

Claims

1. A dual-motor coupled hybrid cutting system for a coal mining machine, comprising an axial flux motor (1), characterized in that: It also includes an active differential (2), a left electronically controlled clutch (3), a left cutting motor (7), a left torque synthesizer (5), a right electronically controlled clutch (4), a right cutting motor (8), a right torque synthesizer (6), a left sensor group, a right sensor group and a controller; The output shaft of the axial flux motor (1) is connected to the input shaft of the active differential (2); One input end of the left torque synthesizer (5) is connected to the left output shaft of the active differential (2) through the left electronically controlled clutch (3), and the other input end is connected to the output shaft of the left cutting motor (7); The left electronically controlled clutch (3) comprises a left hydraulic clutch (12), a left electromagnetic reversing valve (11), a left motor (9), a left working pressure valve (15), a left overflow valve (16) and a left hydraulic pump (10); the left hydraulic clutch (12) comprises a left clutch hydraulic cylinder 1 (13) and a left clutch hydraulic cylinder 2 (14); the left motor (9) is coaxially connected to the left hydraulic pump (10); the oil suction port of the left hydraulic pump (10) is connected to the hydraulic oil tank (17), and the oil discharge port output of the left hydraulic pump (10) is divided into two paths, one of which is connected to the P of the left electromagnetic reversing valve (11) through a pipeline. The oil outlet of the left working pressure valve (15) is divided into two routes, one of which is connected to the rod chamber of the left clutch hydraulic cylinder (13) and the rod chamber of the left clutch hydraulic cylinder (14), and the other is connected to the hydraulic oil tank (17) through the left overflow valve (16); the T port of the left electromagnetic reversing valve (11) is connected to the hydraulic oil tank (17) through a pipeline, the A port thereof is connected to the rodless chamber of the left clutch hydraulic cylinder (13) through a pipeline, and the B port thereof is connected to the rodless chamber of the left clutch hydraulic cylinder (14) through a pipeline; One input end of the right torque synthesizer (6) is connected to the right output shaft of the active differential (2) through the right electronically controlled clutch (4), and the other input end is connected to the output shaft of the right cutting motor (8); The right electronically controlled clutch (4) comprises a right hydraulic clutch (21), a right electromagnetic reversing valve (20), a right motor (18), a right working pressure valve (24), a right overflow valve (25) and a right hydraulic pump (19); the right hydraulic clutch (21) comprises a right clutch hydraulic cylinder 1 (22) and a right clutch hydraulic cylinder 2 (23); the right motor (18) is coaxially connected to the right hydraulic pump (19); the oil suction port of the right hydraulic pump (19) is connected to the hydraulic oil tank (17), and the oil discharge port of the right hydraulic pump (19) is divided into two paths, one of which is connected to the right electromagnetic reversing valve (20) through a pipeline. The first port is connected to the P port, and the other port is connected to the oil inlet of the right working pressure valve (24); the oil outlet of the right working pressure valve (24) is divided into two ports, one port is connected to the rod chamber of the right clutch hydraulic cylinder (22) and the rod chamber of the right clutch hydraulic cylinder (23), respectively, and the other port is connected to the hydraulic oil tank (17) through the right overflow valve (25); the T port of the right electromagnetic reversing valve (20) is connected to the hydraulic oil tank (17) through a pipeline, its A port is connected to the rodless chamber of the right clutch hydraulic cylinder (22) through a pipeline, and its B port is connected to the rodless chamber of the right clutch hydraulic cylinder (23) through a pipeline; The left sensor group includes a left current sensor and a left rotational speed sensor; the left current sensor is connected to the left cutting motor (7) and is used to collect a current signal of the left cutting motor (7) in real time; the left rotational speed sensor is connected to the left cutting motor (7) and is used to collect a rotational speed signal of the left cutting motor (7) in real time; The right sensor group includes a right current sensor and a right rotational speed sensor; the right current sensor is connected to the right cutting motor (8) and is used to collect the second current signal of the right cutting motor (8) in real time; the right rotational speed sensor is connected to the right cutting motor (8) and is used to collect the second rotational speed signal of the right cutting motor (8) in real time; The controller is respectively connected to the left sensor group, the right sensor group, the active differential (2), the left cutting motor (7), the left electromagnetic reversing valve (11), the left motor (9), the right electromagnetic reversing valve (20), the right motor (18) and the right cutting motor (8), and uses the rotation speeds of the left and right cutting motors to control the active differential to dynamically distribute the auxiliary torque, thereby effectively ensuring that the rotation speed of the cutting motor matches its load.

2. A coal mining machine dual-motor coupled hybrid cutting system according to claim 1, characterized in that: The controller is a PLC controller.

3. A coal mining machine dual-motor coupled hybrid cutting system according to claim 2, characterized in that: The left electromagnetic reversing valve (11) and the right electromagnetic reversing valve (20) are both three-position four-way electromagnetic reversing valves. When they are working in the left position, the oil circuit between their P port and A port is connected, and the oil circuit between their T port and B port is connected. When they are working in the middle position, their P port is cut off, and their T port, A port and B port are connected to each other. When they are working in the right position, the oil circuit between their P port and B port is connected, and the oil circuit between their T port and A port is connected.

4. A control method for a dual-motor coupled hybrid cutting system for a coal mining machine, using a dual-motor coupled hybrid cutting system for a coal mining machine according to any one of claims 1 to 3, characterized in that: The following steps are involved: Step 1: When the coal mining machine starts to perform coal mining operations, the left cutting motor (7) and the right cutting motor (8) are controlled to start working synchronously, so that the coal mining machine enters a normal coal seam cutting working mode; Step 2: The left current sensor collects the current signal 1 of the left cutting motor (7) in real time and sends it to the controller; the left speed sensor collects the speed signal 1 of the left cutting motor (7) in real time and sends it to the controller; the right current sensor collects the current signal 2 of the right cutting motor (8) in real time and sends it to the controller; the right speed sensor collects the speed signal 2 of the right cutting motor (8) in real time and sends it to the controller; The controller obtains the current data of the left cutting motor (7) according to the received current signal 1 and speed signal 1. and speed data , and then sense the load state of the left cutting motor (7) in real time; the controller obtains the current data 2 of the right cutting motor (8) according to the received current signal 2 and speed signal 2 and speed data 2 , and then sense the load state of the right cutting motor (8) in real time; Step 3: If the current data of the left cutting motor (7) is Greater than or equal to the overload current threshold And the overload duration Greater than or equal to the duration threshold , it is determined that the left cutting motor (7) is overloaded, and step 4 is directly executed to enter the error update and adaptive gain adjustment process of the left cutting motor (7). Otherwise, the left electromagnetic reversing valve (11) is controlled to work in the neutral position unchanged, so that the left hydraulic clutch (12) is disengaged; If the current data of the right cutting motor (8) is Greater than or equal to the overload current threshold And the overload duration Greater than or equal to the duration threshold , it is determined that the right cutting motor (8) is overloaded, and step 4 is directly executed to enter the error update and adaptive gain adjustment process of the right cutting motor (8); otherwise, the right electromagnetic reversing valve (20) is controlled to work in the neutral position unchanged, so that the right hydraulic clutch (21) is disengaged; Step 4: Update the real-time current error according to the motor load on the overload side , and adaptively adjust the gain of the control parameters on the overload side Adjust to ensure that the power output on the overload side can follow the load changes on the overload side in real time; S41: Obtain the real-time current error of the overload side motor according to formula (1) , and according to the real-time current error Perform error update; （1）； Where, is the actual current at the current moment, is the rated current of the motor; S42: Define the Lyapunov function according to formula (2); （2）； Where, is the ideal parameter value, is the adaptation rate; S43: Derivative the formula (2) to obtain the time rate of change of the Lyapunov function as shown in formula (3). At the same time, ; （3）； Where, is the adaptive parameter update law; S44: Calculated according to formula (4) , and use Update adaptive gain ; （4）； Where, is the regression vector; S45: discretizing the adaptive gain using the Euler forward difference method according to formula (5); （5）； S46: Set the adaptive gain according to formula (6) The upper and lower limits of When the limit value is exceeded, saturation processing is performed to prevent the cutting system from becoming unstable; （6）； Step 5: Calculate the auxiliary torque on the overload side according to the real-time load on the overload side and obtain the required total input torque; S51: Using the updated adaptive gain according to formula (7) and real-time current error Calculation of one-sided assist torque ; （7）； S52: Assist torque according to formula (8) Limiting processing; （8）； S53: Use a first-order low-pass filter to adjust the auxiliary torque Smoothing is performed and the assist torque after smoothing is obtained according to formula (9): ; （9）； S54: Add the smoothed assist torques on the left and right sides according to formula (10) to obtain the required total input torque ; （10）； Step 6: Control the engagement and disengagement of the electronically controlled clutch through the electronically controlled reversing valve to combine the auxiliary power with the output power of the cutting motor according to actual conditions, thereby achieving dynamic assistance to the cutting motor; S61: Control the axial flux motor (1) to start working, and make the torque input from the axial flux motor (1) to the active differential (2) be ; When the corresponding side When the left hydraulic pump (10) is turned on, the controller controls the left motor (9) to drive the left hydraulic pump (10) to work, uses the oil discharge port of the left hydraulic pump (10) to output high-pressure oil, and controls the left electromagnetic reversing valve (11) to work in the left position or the right position, so that the left hydraulic clutch (12) is engaged, and the auxiliary power output from the left output shaft of the active differential (2) is input to one input end of the left torque synthesizer (5). After the power output from the left cutting motor (7) is combined through the coupling effect of the left torque synthesizer (5), the left cutting drum is driven to perform cutting operations. Step 1, control the right motor (18) to drive the right hydraulic pump (19) to work, use the oil discharge port of the right hydraulic pump (19) to output high-pressure oil, and control the right electromagnetic reversing valve (20) to work in the left position or the right position, so that the right hydraulic clutch (21) is engaged, and the auxiliary power output by the right output shaft of the active differential (2) is input to one input end of the right torque synthesizer (6), and the power output by the right cutting motor (8) is combined through the coupling effect of the right torque synthesizer (6) to drive the left cutting drum to perform cutting operation; Synchronously, the output torque of the left cutting motor (7) and the output torque of the right cutting motor (8) are dynamically adjusted according to the distributed torque of the left cutting motor (7) and the distributed torque of the right cutting motor (8), so that the rotation speed of the cutting motor matches its load state. The specific process is as follows: A1: Get the speed data of the left cutting motor (7) in real time and the speed data of the right cutting motor (8) , and calculate the speed difference between the left cutting motor (7) and the right cutting motor (8) according to formula (11) , and Set the threshold value with the speed difference For comparison, if , then execute A2, otherwise, the control keeps the output state of the active differential (2) unchanged and directly executes A3; （11）； A2: According to formula (12), the torque required to be distributed to the left cutting motor (7) is obtained. , and then according to formula (13) obtain the torque required to be distributed to the right cutting motor (8) , the output torque of the left output shaft of the active differential (2) is controlled to be , in order to balance the output of the left cutting motor (7), so that the speed of the left cutting motor (7) and its load tend to be consistent, and control the output torque of the right output shaft of the active differential (2) to be , to balance the output of the right cutting motor (8) so that the speed of the right cutting motor (8) and its load tend to be consistent; （12）； （13）； A3: According to the speed data of the left cutting motor (7) Calculate the output torque of the left cutting motor (7) , and then according to formula (14) the total output torque on the left is obtained , and Perform kinetic analysis to ensure Does not exceed the load capacity of the left mechanical structure and the left cutting motor (7); according to the speed data of the right cutting motor (8) Calculate the output torque of the right cutting motor (8) , and then according to formula (15) the total output torque on the right side is obtained ,and Perform kinetic analysis to ensure Exceeding the load capacity of the right mechanical structure and the right cutting motor (8) （14）； （15）； when When the pressure is reduced to zero or the overload state is released, the left electromagnetic reversing valve (11) is controlled to operate in the middle position, so that the left hydraulic clutch (12) is separated. At the same time, the right electromagnetic reversing valve (20) is controlled to operate in the middle position, so that the right hydraulic clutch (21) is separated, the auxiliary torque output by the active differential (2) is disconnected, and the transmission process of the auxiliary power is stopped; Step 7: Repeat steps 2 to 6 to dynamically adjust the distribution of the auxiliary torque.

5. The control method of the dual-motor coupled hybrid cutting system of a coal mining machine according to claim 4, characterized in that: In step one, the starting parameters of the left cutting motor (7) and the right cutting motor (8) are controlled to be completely consistent.

6. The control method of the dual-motor coupled hybrid cutting system of a coal mining machine according to claim 5, characterized in that: In step 2, the overload current threshold is obtained according to formula (16): , according to formula (17) to obtain the overload current threshold ; （16）； （17）； Where, is the overload coefficient, which is 1.2; is the rated current of the left cutting motor (7), which is 0.

5. is the rated current of the right cutting motor (8), which is 0.

5.

7. A control method for a dual-motor coupled hybrid cutting system for a coal mining machine according to claim 6, characterized in that: In step six, the controller uses PWM to control the actions of the left electromagnetic reversing valve (11) and the right electromagnetic reversing valve (20) to ensure the stability and reliability of the reversing process of the left electromagnetic reversing valve (11) and the right electromagnetic reversing valve (20).

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