Cooperative control method for left and right driving systems of continuous miner

Abstract

The invention belongs to the field of mining variable-frequency driving systems, and aims to solve the problem that a continuous miner is prone to sideslip to cause accidents. The cooperative control method is based on the rotating speed error ratio of a left traction motor and a right traction motor, the ratio of the given values of the output rotating speeds of the left traction motor and the right traction motor and the actual values and the given values of the output torques and the rotating speeds of the left traction motor and the right traction motor. And dynamically adjusting the given values of the output torque and the rotating speed of the left traction motor and the right traction motor at the current moment. Cooperative control of the left driving system and the right driving system of the continuous miner is achieved, the phenomenon that the continuous miner deviates and deviates from an original cutting track due to different left walking resistance and right walking resistance is prevented, and the roadway quality and the tunneling efficiency are improved. And secondly, in the acceleration and deceleration processes of the continuous miner, due to different adhesive forces on the two sides, the problem of slipping at the starting moment of the continuous miner is solved, the rapid drifting phenomenon of the whole miner is avoided, and the equipment safety is improved.

Description

Technical Field

[0001] The invention belongs to the field of variable frequency drive systems for mining, and in particular relates to a coordinated control method for left and right drive systems of a continuous coal mining machine. Background Art

[0002] At present, domestic mining machinery such as continuous miners, anchor miners and shuttle cars all use variable frequency speed regulation for equipment traction, which further improves the traction performance of the equipment compared with hydraulic methods. Continuous miners are not only used for rapid excavation, but also for room-and-pillar coal mining. The performance requirements of variable frequency speed regulation devices are different from those of other coal mining equipment.

[0003] The continuous coal mining machine traction system adopts a left-right drive structure. The transmission devices on both sides have no mechanical connection. Its steering and walking trajectory are completely controlled by the traction systems on both sides. Especially when cutting on the excavation working face, its working mode is to walk and cut simultaneously, and the walking trajectory determines the formation of the tunnel.

[0004] At present, the speed and torque on both sides are not coordinated and controlled. If the resistance on the traction systems on both sides is not equal and the speed drops differently on both sides, the continuous miner will run off the track and deviate from the original cutting trajectory. At this time, the driver has to manually adjust the speed setting of the inverters on both sides to alleviate the impact of different external resistance on the traction system with a small difference between the given speeds. The cut tunnel will appear in a step shape, which cannot meet the excavation requirements and will also affect the excavation speed.

[0005] Secondly, during the acceleration and deceleration process, the continuous coal miner is particularly prone to rapid tail swinging due to the different resistance and adhesion on both sides, causing the tail of the continuous coal miner to collide with the coal wall and cause safety accidents. Summary of the invention

[0006] In order to solve at least one of the above-mentioned technical problems existing in the prior art, the present invention provides a method for coordinated control of left and right drive systems of a continuous coal mining machine.

[0007] The present invention is implemented by the following technical solution: a method for coordinated control of left and right drive systems of a continuous coal mining machine, comprising the following steps:

[0008] Acquire the actual value and given value of the output torque and speed of the left and right traction motors at the previous moment, where the previous moment is the moment before the current moment;

[0009] Based on the difference between the given value and the actual value of the output torque and speed of the left and right traction motors, the torque error and speed error of the left and right traction motors are obtained;

[0010] Based on the speed errors of the left and right traction motors, obtaining a speed error ratio of the left and right traction motors;

[0011] Based on the given values ​​of the output speeds of the left and right traction motors, obtaining a ratio of the given values ​​of the output speeds of the left and right traction motors;

[0012] Based on the speed error ratio of the left and right traction motors, the ratio of the given values ​​of the output speeds of the left and right traction motors, and the actual values ​​and given values ​​of the output torque and speed of the left and right traction motors, the given values ​​of the output torque and speed of the left and right traction motors at the current moment are dynamically adjusted.

[0013] Preferably, based on the current of the left traction motor, the phase of the output current of the left traction inverter, the value and phase of the output voltage of the left traction inverter, and the output frequency of the left traction inverter, combined with the torque constant or speed constant of the traction motor, the actual value of the output torque and speed of the left traction motor is obtained;

[0014] Based on the current of the right traction motor, the phase of the output current of the right traction inverter, the value and phase of the output voltage of the right traction inverter, and the output frequency of the right traction inverter, combined with the torque constant or speed constant of the traction motor, the actual values ​​of the output torque and speed of the right traction motor are obtained.

[0015] Preferably, the step of dynamically adjusting the given values ​​of the output torque and rotational speed of the left and right traction motors at the current moment includes: determining the size of the ratio of the rotational speed error ratio of the left and right traction motors to the given values ​​of the output rotational speeds of the left and right traction motors:

[0016] If the speed error ratio of the left and right traction motors is equal to the ratio of the given values ​​of the output speeds of the left and right traction motors, the output torque is not adjusted;

[0017] If the speed error ratio of the left and right traction motors is greater than or less than the ratio of the given values ​​of the output speeds of the left and right traction motors, the actual values ​​of the output torques of the left and right traction motors are compared with the given values, and the given values ​​of the output torques and speeds of the left and right traction motors at the current moment are dynamically adjusted based on the comparison results.

[0018] Preferably, when the speed error ratio of the left and right traction motors is greater than the ratio of the given values ​​of the output speeds of the left and right traction motors, the step of comparing the actual values ​​of the output torques of the left and right traction motors with the given values ​​is as follows:

[0019] If the given value of the output torque of the left traction motor is equal to the given value of the output torque of the right traction motor, and the actual value of the output torque of the left traction motor is greater than the actual value of the output torque of the right traction motor, the given value of the output torque of the left traction motor is increased, then:

[0020] T L1 =T L2 +k1*(NR2 -N L2 )

[0021] Where, T L1 is the given value of the output torque of the left traction motor, T L2 is the actual value of the output torque of the left traction motor, k1 is the integral coefficient, N R2 is the actual value of the output speed of the right traction motor; N L2 is the actual value of the output speed of the left traction motor;

[0022] If the given value of the output torque of the left traction motor is equal to the given value of the output torque of the right traction motor, and the actual value of the output torque of the left traction motor is less than the actual value of the output torque of the right traction motor, the given values ​​of the output torques of the left and right traction motors are reduced, then:

[0023] T L1＝ T L2 ,T R1＝ T L2

[0024] Where, T R1 is the given value of the output torque of the right traction motor;

[0025] If the given value of the output torque of the left traction motor is greater than the given value of the output torque of the right traction motor, and the actual value of the output torque of the left traction motor is greater than the actual value of the output torque of the right traction motor, the given value of the output torque of the left traction motor is increased, then:

[0026] T L1 =T L2 +k1*(N R2 -N L2 );

[0027] If the given value of the output torque of the left traction motor is greater than the given value of the output torque of the right traction motor, and the actual value of the output torque of the left traction motor is less than the actual value of the output torque of the right traction motor, the given values ​​of the output torques of the left and right traction motors are reduced, then:

[0028] T L1＝ T L2 ,T R1＝ T L2 ;

[0029] If the given value of the output torque of the left traction motor is smaller than the given value of the output torque of the right traction motor, and the actual value of the output torque of the left traction motor is smaller than the actual value of the output torque of the right traction motor, the given values ​​of the output torques of the left and right traction motors are reduced, then:

[0030] T L1＝ T L2,T R1＝ T L2 .

[0031] Preferably, when the speed error ratio of the left and right traction motors is less than the ratio of the given values ​​of the output speeds of the left and right traction motors, the step of comparing the actual values ​​of the output torques of the left and right traction motors with the given values ​​is as follows:

[0032] If the given value of the output torque of the right traction motor is equal to the given value of the output torque of the left traction motor, and the actual value of the output torque of the right traction motor is greater than the actual value of the output torque of the left traction motor, the given value of the output torque of the right traction motor is increased, then:

[0033] T R1 =T R2 +k2*(N L2 -N R2 )

[0034] Where, T R2 is the actual value of the output torque of the right traction motor; k2 is the integral coefficient;

[0035] If the given value of the output torque of the right traction motor is equal to the given value of the output torque of the left traction motor, and the actual value of the output torque of the right traction motor is less than the actual value of the output torque of the left traction motor, the given values ​​of the output torques of the left and right traction motors are reduced, then:

[0036] T L1＝ T R2 ,T R1＝ T R2 ;

[0037] If the given value of the output torque of the right traction motor is greater than the given value of the output torque of the left traction motor, and the actual value of the output torque of the right traction motor is greater than the actual value of the output torque of the left traction motor, the given value of the output torque of the right traction motor is increased, then:

[0038] T R1 =T R2 +k2*(N L2 -N R2 );

[0039] If the given value of the output torque of the right traction motor is greater than the given value of the output torque of the left traction motor, and the actual value of the output torque of the right traction motor is less than the actual value of the output torque of the left traction motor, the given values ​​of the output torques of the left and right traction motors are reduced, then:

[0040] T L1＝ T R2 ,T R1＝ T R2 ;

[0041] If the given value of the output torque of the right traction motor is smaller than the given value of the output torque of the left traction motor, and the actual value of the output torque of the right traction motor is smaller than the actual value of the output torque of the left traction motor, the given values ​​of the output torques of the left and right traction motors are reduced, then:

[0042] T L1＝ T R2 ,T R1＝ T R2 .

[0043] Preferably, the period for dynamically adjusting the given values ​​of the output torque and rotation speed of the left and right traction motors at the current moment is 1 s.

[0044] Preferably, the calculation formula for the actual values ​​of the output torque and speed of the left traction motor is:

[0045] N L2 =k3*I L *U L *cos(ψ UL -ψ IL ) / f L

[0046] T L2 =k4*I L *U L *cos(ψ UL -ψ IL ) / N L2

[0047] Where, k3 and k4 are the speed constant and torque constant of the traction motor, I L is the current of the left traction motor, U L is the output voltage of the left traction inverter, ψ UL is the phase of the output voltage of the left traction inverter, ψ IL is the phase of the output current of the left traction inverter, f L is the output frequency of the left traction inverter.

[0048] Preferably, the calculation formula for the actual values ​​of the output torque and speed of the right traction motor is:

[0049] N R2 =k3*I R *U R *cos(ψ UR -ψ IR ) / f R

[0050] T R2 =k4*I R *U R *cos(ψUR -ψ IR ) / N R2

[0051] In the formula, I R is the current of the right traction motor, U R is the output voltage of the right traction inverter, ψ UR is the phase of the output voltage of the right traction inverter, ψ IR is the phase of the output current of the right traction inverter, f R is the output frequency of the right traction inverter.

[0052] Compared with the prior art, the present invention has the following beneficial effects:

[0053] The present invention provides a method for coordinated control of the left and right drive systems of a continuous coal mining machine. The method achieves coordinated control of the left and right drive systems of a continuous coal mining machine by observing the actual values ​​of the output torque and speed of the left and right drive systems at the last moment, and combining the given values ​​of the torque and speed at the last moment to calculate the target values ​​of the torque and speed of the left and right drive systems at the current moment. This prevents the continuous mining machine from running off the track and deviating from the original cutting trajectory due to different walking resistances on the left and right sides, thereby improving the quality of the tunnel and the efficiency of excavation. Secondly, during the acceleration and deceleration process of the continuous coal mining machine, due to the different adhesion forces on both sides, the problem of slipping at the moment of starting the continuous mining machine is overcome, the phenomenon of rapid tail swinging of the whole machine is avoided, and the safety of the equipment is improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0055] Figure 1 It is a flow chart of a method for coordinated control of left and right drive systems of a continuous coal mining machine provided by an embodiment of the present invention;

[0056] Figure 2 It is a control hardware schematic diagram of a method for coordinated control of left and right drive systems of a continuous coal mining machine according to an embodiment of the present invention. DETAILED DESCRIPTION

[0057] In conjunction with the drawings in the embodiments of the present invention, the technical solutions in the embodiments of the present invention are clearly and completely described. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other implementation methods obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0058] It should be noted that the structures, proportions, sizes, etc. illustrated in the drawings of this specification are only used to match the contents disclosed in the specification for people familiar with this technology to understand and read, and are not used to limit the conditions under which the present invention can be implemented. Therefore, they have no substantive technical significance. Any structural modification, change in proportional relationship or adjustment of size should fall within the scope of the technical contents disclosed in the present invention without affecting the effects and purposes that can be achieved by the present invention. It should be noted that in this specification, relational terms such as first and second are only used to distinguish one entity from other entities, and do not necessarily require or imply any actual relationship or order between these entities.

[0059] The present invention provides an embodiment:

[0060] like Figure 1 , Figure 2 As shown, a method for coordinated control of left and right drive systems of a continuous coal mining machine comprises the following steps:

[0061] Acquire the actual value and given value of the output torque and speed of the left and right traction motors at the previous moment, where the previous moment is the moment before the current moment;

[0062] Based on the difference between the given value and the actual value of the output torque and speed of the left and right traction motors, the torque error and speed error of the left and right traction motors are obtained;

[0063] Based on the speed errors of the left and right traction motors, obtaining a speed error ratio of the left and right traction motors;

[0064] Based on the given values ​​of the output speeds of the left and right traction motors, obtaining a ratio of the given values ​​of the output speeds of the left and right traction motors;

[0065] Based on the speed error ratio of the left and right traction motors, the ratio of the given values ​​of the output speeds of the left and right traction motors, and the actual values ​​and given values ​​of the output torque and speed of the left and right traction motors, the given values ​​of the output torque and speed of the left and right traction motors at the current moment are dynamically adjusted.

[0066] Based on the current of the left traction motor, the phase of the output current of the left traction inverter, the value and phase of the output voltage of the left traction inverter, and the output frequency of the left traction inverter, combined with the torque constant or speed constant of the traction motor, the actual values ​​of the output torque and speed of the left traction motor are obtained; based on the current of the right traction motor, the phase of the output current of the right traction inverter, the value and phase of the output voltage of the right traction inverter, and the output frequency of the right traction inverter, combined with the torque constant or speed constant of the traction motor, the actual values ​​of the output torque and speed of the right traction motor are obtained.

[0067] The output torque and speed of the left traction motor are defined as: T L1 、N L1 , the actual values ​​of the output torque and speed of the left traction motor are: T L2 、N L2 ; The given values ​​of the output torque and speed of the right traction motor are: T R1 、N R1 , the actual values ​​of the output torque and speed of the left traction motor are: N R2 、N R2 ;

[0068] The torque error of the left traction motor is: T Lδ =T L1 -T L2 ; The speed error of the left traction motor is: N Lδ =N L1 -N L2 ;

[0069] The torque error of the right traction motor is: T Rδ =T R1 -T R2 ; The speed error of the right traction motor is: N Rδ =N R1 -N R2 .

[0070] Specifically, the calculation formula for the actual values ​​of the output torque and speed of the left traction motor is:

[0071] N L2 =k3*I L *U L *cos(ψ UL -ψ IL ) / f L

[0072] T L2 =k4*I L *U L *cos(ψ UL -ψ IL ) / N L2

[0073] Where, k3 and k4 are the speed constant and torque constant of the traction motor, I L is the current of the left traction motor, U L is the output voltage of the left traction inverter, ψ UL is the phase of the output voltage of the left traction inverter, ψ IL is the phase of the output current of the left traction inverter, f L is the output frequency of the left traction inverter.

[0074] The calculation formula for the actual value of the output torque and speed of the right traction motor is:

[0075] N R2 =k3*I R *U R *cos(ψ UR -ψ IR ) / f R

[0076] T R2 =k4*I R *U R *cos(ψ UR -ψ IR ) / N R2

[0077] In the formula, I R is the current of the right traction motor, U R is the output voltage of the right traction inverter, ψ UR is the phase of the output voltage of the right traction inverter, ψ IR is the phase of the output current of the right traction inverter, f R is the output frequency of the right traction inverter.

[0078] The step of dynamically adjusting the given values ​​of the output torque and rotation speed of the left and right traction motors at the current moment includes: determining the size of the ratio of the rotation speed error ratio of the left and right traction motors to the given values ​​of the output rotation speed of the left and right traction motors:

[0079] If the speed error ratio of the left and right traction motors is equal to the ratio of the given values ​​of the output speeds of the left and right traction motors (N Lδ / N Rδ =N L1 / N R1 ), indicating that the ratio of the speed reduction of the left and right traction motors is equal to the given ratio, and the output torque is not adjusted; if the speed error ratio of the left and right traction motors is greater than or less than the ratio of the given values ​​of the output speeds of the left and right traction motors, the actual values ​​of the output torques of the left and right traction motors are compared with the given values, and based on the comparison results, the given values ​​of the output torques and speeds of the left and right traction motors at the current moment are dynamically adjusted.

[0080] Specifically, when the speed error ratio of the left and right traction motors is greater than the ratio of the given values ​​of the output speeds of the left and right traction motors (N Lδ / N Rδ >N L1 / N R1), indicating that the speed drop of the left traction motor is greater than the speed drop of the right traction motor. The following five states are discussed in total. The steps for comparing the actual value and the given value of the output torque of the left and right traction motors are as follows:

[0081] 1. If the given value of the output torque of the left traction motor is equal to the given value of the output torque of the right traction motor, and the actual value of the output torque of the left traction motor is greater than the actual value of the output torque of the right traction motor (T L1 =T R1 , T L2 >T R2 ), indicating that the left wheel resistance is large, and it is necessary to increase the torque given by the left traction motor. To increase the given value of the output torque of the left traction motor, then:

[0082] T L1 =T L2 +k1*(N R2 -N L2 )

[0083] Where, T L1 is the given value of the output torque of the left traction motor, T L2 is the actual value of the output torque of the left traction motor, k1 is the integral coefficient, N R2 is the actual value of the output speed of the right traction motor; N L2 is the actual value of the output speed of the left traction motor;

[0084] 2. If the given value of the output torque of the left traction motor is equal to the given value of the output torque of the right traction motor, and the actual value of the output torque of the left traction motor is less than the actual value of the output torque of the right traction motor (T L1 =T R1 , T L2 <T R2 ), indicating that the left wheel is slipping. If the given values ​​of the output torques of the left and right traction motors are reduced, then:

[0085] T L1＝ T L2 ,T R1＝ T L2

[0086] Where, T R1 is the given value of the output torque of the right traction motor;

[0087] 3. If the given value of the output torque of the left traction motor is greater than the given value of the output torque of the right traction motor, and the actual value of the output torque of the left traction motor is greater than the actual value of the output torque of the right traction motor (T L1 >T R1 , T L2 >T R2), indicating that the left wheel resistance is large, increasing the given value of the output torque of the left traction motor, then:

[0088] T L1 =T L2 +k1*(N R2 -N L2 );

[0089] 4. If the given value of the output torque of the left traction motor is greater than the given value of the output torque of the right traction motor, and the actual value of the output torque of the left traction motor is less than the actual value of the output torque of the right traction motor (T L1 >T R1 , T L2 <T R2 ), indicating that the left wheel is slipping. If the given values ​​of the output torques of the left and right traction motors are reduced, then:

[0090] T L1＝ T L2 ,T R1＝ T L2 ;

[0091] 5. If the given value of the output torque of the left traction motor is less than the given value of the output torque of the right traction motor, and the actual value of the output torque of the left traction motor is less than the actual value of the output torque of the right traction motor (T L1 <T R1 , T L2 <T R2 ), indicating that the left wheel is slipping. If the given values ​​of the output torques of the left and right traction motors are reduced, then:

[0092] T L1＝ T L2 ,T R1＝ T L2 .

[0093] 2. When the speed error ratio of the left and right traction motors is less than the ratio of the given values ​​of the output speeds of the left and right traction motors (N Lδ / N Rδ <N L1 / N R1 ), indicating that the right wheel speed decreases more than the left wheel speed decrease. The following five states are discussed in total. The steps for comparing the actual value and the given value of the output torque of the left and right traction motors are as follows:

[0094] If the given value of the output torque of the right traction motor is equal to the given value of the output torque of the left traction motor, and the actual value of the output torque of the right traction motor is greater than the actual value of the output torque of the left traction motor (T R1 =T L1 , T R2 >TL2 ), indicating that the right wheel resistance is large, increasing the given value of the output torque of the right traction motor, then:

[0095] T R1 =T R2 +k2*(N L2 -N R2 )

[0096] Where, T R2 is the actual value of the output torque of the right traction motor; k2 is the integral coefficient;

[0097] If the given value of the output torque of the right traction motor is equal to the given value of the output torque of the left traction motor, and the actual value of the output torque of the right traction motor is less than the actual value of the output torque of the left traction motor (T R1 =T L1 , T R2 <T L ), indicating that the right wheel is slipping. If the given values ​​of the output torques of the left and right traction motors are reduced, then:

[0098] T L1＝ T R2 ,T R1＝ T R2 ;

[0099] If the given value of the output torque of the right traction motor is greater than the given value of the output torque of the left traction motor, and the actual value of the output torque of the right traction motor is greater than the actual value of the output torque of the left traction motor (T R1 >T L1 , T R2 >T L2 ), indicating that the right wheel resistance is large, increasing the given value of the output torque of the right traction motor, then:

[0100] T R1 =T R2 +k2*(N L2 -N R2 );

[0101] If the given value of the output torque of the right traction motor is greater than the given value of the output torque of the left traction motor, and the actual value of the output torque of the right traction motor is less than the actual value of the output torque of the left traction motor (T R1 >T L1 , T R2 <T L2 ), indicating that the right wheel is slipping. If the given values ​​of the output torques of the left and right traction motors are reduced, then:

[0102] T L1＝ T R2 ,T R1＝ TR2 ;

[0103] If the given value of the output torque of the right traction motor is less than the given value of the output torque of the left traction motor, and the actual value of the output torque of the right traction motor is less than the actual value of the output torque of the left traction motor (T R1 <T L1 , T R2 <T L2 ), indicating that the right wheel is slipping. If the given values ​​of the output torques of the left and right traction motors are reduced, then:

[0104] T L1＝ T R2 ,T R1＝ T R2 .

[0105] The cycle of dynamically adjusting the given values ​​of the output torque and speed of the left and right traction motors at the current moment is 1s. According to the feedback of the traction motor torque and speed, the traction motor torque setting is dynamically adjusted to realize the automatic correlation control of the speed of the traction motors on both sides. The integral coefficients k1 and k2 are determined jointly according to the whole machine dynamics model and kinematic model, 0 <k1<1,0<k2<1。

[0106] The above is only a preferred specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed by the present invention should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention shall be based on the protection scope of the claims.

Claims

1. A method for coordinated control of left and right drive systems of a continuous coal mining machine, characterized in that: The following steps are involved: Acquire the actual value and given value of the output torque and speed of the left and right traction motors at the previous moment, where the previous moment is the moment before the current moment; Based on the difference between the given value and the actual value of the output torque and speed of the left and right traction motors, the torque error and speed error of the left and right traction motors are obtained; Based on the speed errors of the left and right traction motors, obtaining a speed error ratio of the left and right traction motors; Based on the given values ​​of the output speeds of the left and right traction motors, obtaining a ratio of the given values ​​of the output speeds of the left and right traction motors; Based on the speed error ratio of the left and right traction motors, the ratio of the given values ​​of the output speeds of the left and right traction motors, and the actual values ​​and given values ​​of the output torque and speed of the left and right traction motors, the given values ​​of the output torque and speed of the left and right traction motors at the current moment are dynamically adjusted.

2. A method for coordinated control of left and right drive systems of a continuous coal mining machine according to claim 1, characterized in that: Based on the current of the left traction motor, the phase of the output current of the left traction inverter, the value and phase of the output voltage of the left traction inverter, and the output frequency of the left traction inverter, combined with the torque constant or speed constant of the traction motor, the actual value of the output torque and speed of the left traction motor is obtained; Based on the current of the right traction motor, the phase of the output current of the right traction inverter, the value and phase of the output voltage of the right traction inverter, and the output frequency of the right traction inverter, combined with the torque constant or speed constant of the traction motor, the actual values ​​of the output torque and speed of the right traction motor are obtained.

3. The method for coordinated control of left and right drive systems of a continuous coal mining machine according to claim 1, characterized in that: The step of dynamically adjusting the given values ​​of the output torque and rotation speed of the left and right traction motors at the current moment includes: determining the size of the ratio of the rotation speed error ratio of the left and right traction motors to the given values ​​of the output rotation speed of the left and right traction motors: If the speed error ratio of the left and right traction motors is equal to the ratio of the given values ​​of the output speeds of the left and right traction motors, the output torque is not adjusted; If the speed error ratio of the left and right traction motors is greater than or less than the ratio of the given values ​​of the output speeds of the left and right traction motors, the actual values ​​of the output torques of the left and right traction motors are compared with the given values, and the given values ​​of the output torques and speeds of the left and right traction motors at the current moment are dynamically adjusted based on the comparison results.

4. A method for coordinated control of left and right drive systems of a continuous coal mining machine according to claim 3, characterized in that: When the speed error ratio of the left and right traction motors is greater than the ratio of the given values ​​of the output speeds of the left and right traction motors, the steps of comparing the actual values ​​of the output torques of the left and right traction motors with the given values ​​are as follows: If the given value of the output torque of the left traction motor is equal to the given value of the output torque of the right traction motor, and the actual value of the output torque of the left traction motor is greater than the actual value of the output torque of the right traction motor, the given value of the output torque of the left traction motor is increased, then: T L1 =T L2 +k1*(N R2 -N L2 ) Where, T L1 is the given value of the output torque of the left traction motor, T L2 is the actual value of the output torque of the left traction motor, k1 is the integral coefficient, N R2 is the actual value of the output speed of the right traction motor; N L2 is the actual value of the output speed of the left traction motor; If the given value of the output torque of the left traction motor is equal to the given value of the output torque of the right traction motor, and the actual value of the output torque of the left traction motor is less than the actual value of the output torque of the right traction motor, the given values ​​of the output torques of the left and right traction motors are reduced, then: T L1＝ T L2 ,T R1＝ T L2 Where, T R1 is the given value of the output torque of the right traction motor; If the given value of the output torque of the left traction motor is greater than the given value of the output torque of the right traction motor, and the actual value of the output torque of the left traction motor is greater than the actual value of the output torque of the right traction motor, the given value of the output torque of the left traction motor is increased, then: T L1 =T L2 +k1*(N R2 -N L2 ); If the given value of the output torque of the left traction motor is greater than the given value of the output torque of the right traction motor, and the actual value of the output torque of the left traction motor is less than the actual value of the output torque of the right traction motor, the given values ​​of the output torques of the left and right traction motors are reduced, then: T L1＝ T L2 ,T R1＝ T L2 ; If the given value of the output torque of the left traction motor is smaller than the given value of the output torque of the right traction motor, and the actual value of the output torque of the left traction motor is smaller than the actual value of the output torque of the right traction motor, the given values ​​of the output torques of the left and right traction motors are reduced, then: T L1＝ T L2 ,T R1＝ T L2 。 5. A method for coordinated control of left and right drive systems of a continuous coal mining machine according to claim 4, characterized in that: When the speed error ratio of the left and right traction motors is less than the ratio of the given values ​​of the output speeds of the left and right traction motors, the steps of comparing the actual values ​​of the output torques of the left and right traction motors with the given values ​​are as follows: If the given value of the output torque of the right traction motor is equal to the given value of the output torque of the left traction motor, and the actual value of the output torque of the right traction motor is greater than the actual value of the output torque of the left traction motor, the given value of the output torque of the right traction motor is increased, then: T R1 =T R2 +k2*(N L2 -N R2 ) Where, T R2 is the actual value of the output torque of the right traction motor; k2 is the integral coefficient; If the given value of the output torque of the right traction motor is equal to the given value of the output torque of the left traction motor, and the actual value of the output torque of the right traction motor is less than the actual value of the output torque of the left traction motor, the given values ​​of the output torques of the left and right traction motors are reduced, then: T L1＝ T R2 ,T R1＝ T R2 ; If the given value of the output torque of the right traction motor is greater than the given value of the output torque of the left traction motor, and the actual value of the output torque of the right traction motor is greater than the actual value of the output torque of the left traction motor, the given value of the output torque of the right traction motor is increased, then: T R1 =T R2 +k2*(N L2 -N R2 ); If the given value of the output torque of the right traction motor is greater than the given value of the output torque of the left traction motor, and the actual value of the output torque of the right traction motor is less than the actual value of the output torque of the left traction motor, the given values ​​of the output torques of the left and right traction motors are reduced, then: T L1＝ T R2 ,T R1＝ T R2 ; If the given value of the output torque of the right traction motor is smaller than the given value of the output torque of the left traction motor, and the actual value of the output torque of the right traction motor is smaller than the actual value of the output torque of the left traction motor, the given values ​​of the output torques of the left and right traction motors are reduced, then: T L1＝ T R2 ,T R1＝ T R2 。 6. A method for coordinated control of left and right drive systems of a continuous coal mining machine according to claim 1, characterized in that: The cycle for dynamically adjusting the given values ​​of the output torque and speed of the left and right traction motors at the current moment is 1s.

7. A method for coordinated control of left and right drive systems of a continuous coal mining machine according to claim 2, characterized in that: The calculation formula for the actual value of the output torque and speed of the left traction motor is: N L2 =k3*I L *U L *cos(ψ UL -ψ IL ) / f L T L2 =k4*I L *U L *cos(ψ UL -ψ IL ) / N L2 Where, k3 and k4 are the speed constant and torque constant of the traction motor, I L is the current of the left traction motor, U L is the output voltage of the left traction inverter, ψ UL is the phase of the output voltage of the left traction inverter, ψ IL is the phase of the output current of the left traction inverter, f L is the output frequency of the left traction inverter.

8. A method for coordinated control of left and right drive systems of a continuous coal mining machine according to claim 7, characterized in that: The calculation formula for the actual value of the output torque and speed of the right traction motor is: N R2 =k3*I R *U R *cos(ψ UR -ψ IR ) / f R T R2 =k4*I R *U R *cos(ψ UR -ψ IR ) / N R2 In the formula, I R is the current of the right traction motor, U R is the output voltage of the right traction inverter, ψ UR is the phase of the output voltage of the right traction inverter, ψ IR is the phase of the output current of the right traction inverter, f R is the output frequency of the right traction inverter.

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