Anti-backlash control method and device for dual-motor driving gear system

Abstract

The invention discloses an anti-backlash control method and device for a dual-motor driving gear system, and relates to the technical field of servo control, and the method comprises the steps: obtaining the information of the dual-motor driving gear system, obtaining the reference position information of a large gear and the actual position information of the large gear based on the dual-motor driving gear system, and according to the reference position information and the actual position information of the bull gear, based on torque coupling compensation, obtaining a backlash-canceling bias current. Through cooperative control of the two motors, torque deviation is compensated in real time, the return difference problem in gear transmission can be effectively eliminated, a torque coupling compensation control algorithm based on speed deviation can quickly respond to load change and motion state switching, it is ensured that the system is still kept stable under the high-dynamic condition, and the stability of the system is improved. And a torque balance mechanism of dual-motor cooperative work improves the stability and anti-interference capability of the system, and meets the precision transmission requirements under complex working conditions.

Description

Technical Field

[0001] The present invention relates to the technical field of servo control, and in particular to a backlash elimination control method and device for a dual-motor driven gear system. Background Art

[0002] In turntable servo systems, mechanical reduction gears are often required to match the high speed, low torque output of the motor with the low speed, high torque requirements of the load. Gear transmissions are widely used due to their stable transmission ratios and compact structure. However, in practice, gear transmissions often have tooth backlash (backlash), which causes hysteresis in the transmission system during commutation or load changes, affecting the system's control accuracy and stability.

[0003] Traditional methods for eliminating or reducing the adverse effects of backlash include mechanical and electrical backlash reduction. Mechanical backlash reduction is typically achieved by adjusting the meshing position of the gears or increasing the preload. However, this method is limited by the mechanical structure, making it difficult to transmit large torques and requiring complex adjustments. For applications with high loads and high acceleration, mechanical backlash reduction is limited in effectiveness, resulting in high implementation costs and complex processes.

[0004] Therefore, there is an urgent need for a control method and device that can effectively eliminate tooth backlash and improve the performance of the gear transmission system. Summary of the Invention

[0005] In order to solve the problem of insufficient control accuracy and stability of a dual-motor driven gear system due to tooth backlash in the above background technology, the present invention provides a backlash elimination control method and device for a dual-motor driven gear system.

[0006] In order to achieve the above objects, the technical solution adopted by the present invention is:

[0007] A backlash control method for a dual-motor driven gear system, comprising:

[0008] Acquire dual-motor drive gear system information, wherein the dual-motor drive gear system includes main shaft servo motor information, slave shaft servo motor information, large gear information, and small gear information;

[0009] Based on the dual-motor driven gear system, the reference position information and actual position information of the large gear are obtained;

[0010] According to the reference position information and the actual position information of the gear, the anti-backlash bias current is obtained based on the torque coupling compensation;

[0011] According to the anti-backlash bias current, the main axis servo motor current and the slave axis servo motor current are adjusted.

[0012] Preferably, the step of obtaining the anti-backlash bias current based on the torque coupling compensation according to the gearwheel reference position information and the gearwheel actual position information specifically includes:

[0013] Obtaining a position deviation value according to the reference position information of the large gear and the actual position information of the large gear;

[0014] Based on the PID controller, the reference speed value is calculated based on the position deviation value;

[0015] According to the dual-motor drive gear system information, the actual speed information of the main shaft and the actual speed information of the slave shaft are obtained;

[0016] Obtain the anti-backlash bias current according to the reference speed value, the actual speed information of the master axis, and the actual speed information of the slave axis.

[0017] Preferably, obtaining the anti-backlash bias current according to the reference speed value, the actual speed information of the main shaft and the actual speed information of the slave shaft specifically includes:

[0018] The difference between the reference speed value and the actual spindle speed is used as the spindle speed deviation value;

[0019] The difference between the reference speed value and the actual speed of the slave axis is used as the slave axis speed deviation value;

[0020] According to the main shaft speed deviation value and the slave shaft speed deviation value, based on the PID controller, the main shaft torque current reference value and the slave shaft torque current reference value are calculated respectively;

[0021] According to the spindle torque current reference value, the spindle anti-backlash bias current is added to the spindle torque current to obtain the spindle motor current information;

[0022] According to the slave axis torque current reference value, the master axis anti-backlash bias current is added to the slave axis torque current to obtain the slave axis motor current information;

[0023] Based on the torque balance analysis, the main shaft motor current and the slave shaft motor current are adjusted to obtain the anti-backlash bias current.

[0024] Preferably, the adjusting of the main shaft motor current and the slave shaft motor current based on the torque balance analysis to obtain the anti-backlash bias current specifically includes:

[0025] Obtain the spindle torque according to the spindle motor current;

[0026] Obtain the slave shaft torque according to the slave shaft motor current;

[0027] The main shaft motor current and the slave shaft motor current are adjusted until the main shaft torque and the slave shaft torque are balanced to obtain the anti-backlash bias current.

[0028] Furthermore, a backlash control device for a dual-motor driven gear system is proposed to implement the above analysis method, comprising:

[0029] A spindle servo motor, which is used to drive the small gear 1 and mesh with the large gear;

[0030] A slave shaft servo motor, the slave shaft servo motor is used to drive the small gear 2 to mesh with the large gear;

[0031] A large gear, which is driven by the small gears driven by the master and slave motors respectively, and is connected to the load for rotation;

[0032] a PID controller, the PID controller interacting with the main axis servo motor and the slave axis servo motor for signal processing and execution of a control algorithm;

[0033] A synchronization card is used for data exchange and synchronization control between the main shaft servo motor and the slave shaft servo motor;

[0034] The encoder can feed back the position and speed information of the gear to the controller in real time.

[0035] Compared with the prior art, the present invention has the following beneficial effects:

[0036] The present invention proposes a backlash control method and device for a dual-motor driven gear system. Through the coordinated control of the dual motors, torque deviation can be compensated in real time, which can effectively eliminate the backlash problem in the gear transmission. The torque coupling compensation control algorithm based on speed deviation can quickly respond to load changes and motion state switching, ensuring that the system remains stable under high dynamic conditions. The torque balancing mechanism of the dual motors working in coordination improves the stability and anti-interference ability of the system, and adapts to the precision transmission requirements under complex working conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 This is a flow chart of a backlash elimination control method for a dual-motor driven gear system proposed by the present invention;

[0038] Figure 2 This is a flow chart for obtaining the anti-backlash bias current in the present invention;

[0039] Figure 3 Schematic diagram of the structure of the dual-motor driven gear transmission device in the present invention;

[0040] Figure 4 This is a diagram showing the relationship between the dual motor driving torque and current in the present invention;

[0041] Figure 5 This is a schematic diagram of the counterclockwise movement of the large gear in the present invention;

[0042] Figure 6This is a schematic diagram of the clockwise movement of the large gear in the present invention;

[0043] Figure 7 This is a block diagram of the dual-motor driven gear synchronous backlash control algorithm of the present invention;

[0044] Figure 8 This is a structural block diagram of the anti-backlash control device for a dual-motor driven gear system proposed by the present invention. DETAILED DESCRIPTION

[0045] The following description is intended to disclose the present invention so that those skilled in the art can implement the present invention. The preferred embodiments described below are merely examples, and those skilled in the art may conceive of other obvious variations.

[0046] Reference Figure 1 - Figure 4 As shown, a backlash control method for a dual-motor driven gear system in an embodiment of the present invention includes:

[0047] Acquire dual-motor drive gear system information, wherein the dual-motor drive gear system includes main shaft servo motor information, slave shaft servo motor information, large gear information, and small gear information;

[0048] Based on the dual-motor driven gear system, the reference position information and actual position information of the large gear are obtained;

[0049] According to the reference position information and the actual position information of the gear, the anti-backlash bias current is obtained based on the torque coupling compensation;

[0050] Specifically, according to the large gear reference position information and the large gear actual position information, based on the torque coupling compensation, the anti-backlash bias current is obtained, which specifically includes:

[0051] According to the large gear reference position information and the large gear actual position information, the position deviation value is obtained:

[0052]

[0053] Where, is the position deviation value, act Indicates the actual position of the large gear, ref Indicates the reference position of the large gear;

[0054] Based on the PID controller, the reference speed value is calculated based on the position deviation value, that is:

[0055] n ref =PID();

[0056] According to the dual-motor drive gear system information, the actual speed information of the main shaft and the actual speed information of the slave shaft are obtained;

[0057] Obtain the anti-backlash bias current according to the reference speed value, the actual speed information of the master axis, and the actual speed information of the slave axis.

[0058] Specifically, the anti-backlash bias current is obtained according to the reference speed value, the actual speed information of the main axis and the actual speed information of the slave axis, which specifically includes:

[0059] The reference speed value n ref The actual spindle speed n act,M The difference is taken as the spindle speed deviation value:

[0060] Δn M =n ref ―n act,M ;

[0061] The reference speed value n ref The actual speed n of the slave axis act,S The difference is taken as the slave axis speed deviation value:

[0062] Δn S =n ref ―n act,S ;

[0063] According to the main shaft speed deviation value and the slave shaft speed deviation value, the main shaft torque current reference value and the slave shaft torque current reference value are calculated based on the PID controller:

[0064]

[0065] Where i sqref,M is the main shaft torque current reference value, i sqref,S is the reference value of the slave shaft torque current;

[0066] According to the spindle torque current reference value, the spindle anti-backlash bias current is added to the spindle torque current to obtain the spindle motor current information;

[0067] According to the slave axis torque current reference value, the master axis anti-backlash bias current is added to the slave axis torque current to obtain the slave axis motor current information;

[0068] Based on the torque balance analysis, the main shaft motor current and the slave shaft motor current are adjusted to obtain the anti-backlash bias current.

[0069] In this solution, the torque current reference value i of the master and slave motors is exchanged in real time through the synchronization card. sqref,M and i sqref,S .

[0070] Perform coupling control PID adjustment to compensate for the torque deviation between the dual motors.

[0071] Add anti-backlash bias current i isq,bias,M and i isq,bias,S :

[0072] i M =i sqref,M +i isq,bias,M

[0073] i S =i sqref,S +i isq,bias,S

[0074] The adjusted current value i M and i S Send to the servo driver to drive the master and slave motors to perform synchronous control;

[0075] Specifically, based on the torque balance analysis, the main shaft motor current and the slave shaft motor current are adjusted to obtain the anti-backlash bias current, which specifically includes:

[0076] Obtain the spindle torque according to the spindle motor current;

[0077] Obtain the slave shaft torque according to the slave shaft motor current;

[0078] The main shaft motor current and the slave shaft motor current are adjusted until the main shaft torque and the slave shaft torque are balanced to obtain the anti-backlash bias current;

[0079] In this embodiment, the relationship between the torque and current of the main shaft motor (M) and the slave shaft motor (S) is:

[0080] M=K t I;

[0081] Among them, M is the motor output torque, K t is the torque constant, and I is the motor current. Since the configuration of the master and slave motors is opposite, when the main shaft motor outputs torque M M When the slave motor outputs torque M S =-M M When there is no control signal input, the system maintains a static equilibrium state.

[0082] According to the anti-backlash bias current, the main axis servo motor current and the slave axis servo motor current are adjusted.

[0083] It is understandable that mechanical reduction devices are often used in turntable servo systems. This is because the motor as the driving element has a high output speed but a small torque; while the load movement requires a large torque but a low speed; a mechanical transmission device is needed to match the two, usually a gear transmission device.

[0084] Ideally, the relationship between the input and output of a gear transmission is linear. However, in practice, there is always a gap between the teeth of a pair of meshing gears, also known as backlash. The existence of backlash causes backlash in transmissions that work in reciprocating motion.

[0085] In order to eliminate or reduce the clearance of transmission gears, mechanical or electrical clearance elimination methods are usually used to solve the problem. Mechanical clearance elimination can only be used to transmit smaller torques, while for power transmissions with large loads and high accelerations, it is best to use electrical clearance elimination methods to solve the problem. This article uses a dual-motor electrical synchronous clearance elimination method to solve the gap between gear transmissions. Two sets of completely identical servo motors drive a pair of small gears, which are respectively pressed against the opposite meshing surfaces of the loaded large gear, so that the large gear is subjected to a bias torque and can no longer swing back and forth in the tooth gap, thereby achieving the purpose of clearance elimination.

[0086] like Figure 3 As shown in the figure, two identical servo motors are used, each driving two small gears. These two small gears mesh with a large gear, which in turn drives the load. Backlash elimination is achieved by simultaneously establishing a bias current between the two motors driving the small gears when the large gear is started or reversed, thereby generating a bias torque to eliminate backlash.

[0087] To achieve anti-backlash control, the ideal solution is to use two motors as forward drive and reverse drive power motors respectively. The forward motor maintains an output of a forward torque sufficient to eliminate the transmission gap when reversing, and the reverse motor maintains an output of a reverse torque sufficient to eliminate the transmission gap when rotating forward.

[0088] When the motor control signal is 0, that is, the current is 0, the master and slave motors output equal and opposite torques, that is, the bias torque M bias,M and M bias,S , which makes the two small gears stick to the opposite side tooth surface of the large gear. Since the torque of the master and slave motors is proportional to the current, the coefficient is the torque constant k of the drive motor t , the curve of torque and current is a straight line, but due to the existence of bias current, the two torque and current curves of the master and slave shaft pinions are two parallel lines, and the maximum and minimum drives of the entire dual-motor drive system are +M and +M, respectively. 1,2max , ―M 1,2max , so we can get the torque curve of the dual motor drive system as follows Figure 4 shown.

[0089] During the startup of the load, when the large gear rotates clockwise, the current of the master and slave motors will start from point 1, pass through points 2, 3, and 4, and reach the maximum driving torque at point 5.

[0090] The specific working process is as follows:

[0091] At point 1, the driving torques of the two small gears are equal in magnitude and opposite in direction, i.e., |M1|=|M2|. The two small gears are attached to two opposite meshing positions of the large gear, and the total torque on the large gear is zero, so the large gear does not rotate.

[0092] At point 2, the torque |M1| on the main shaft pinion 1 is greater than the torque |M2| on the slave shaft pinion 2, and the total torque on the large gear is greater than zero, so the large gear starts to rotate.

[0093] After passing point 3, the torque |M2| on the slave pinion 2 is also greater than zero. The two pinions are attached to the same tooth surface of the large gear and drive the large gear to rotate at the same time.

[0094] At point 4, the torque acting on the main shaft pinion 1 reaches the maximum driving torque and enters the saturation state;

[0095] At point 5, the main shaft pinion 1 and the slave shaft pinion 2 reach the maximum driving torque at the same time.

[0096] Similarly, when the large gear rotates counterclockwise, the current flowing through the master and slave motors starts at point 1, passes through points 6, 7, and 8, and reaches maximum drive torque at point 9. This indicates that during the initial startup phase, the bias torque prevents the large gear from swinging back and forth within the gear gap, completely eliminating backlash error. Later in the startup phase, both motors simultaneously drive the load, fully utilizing their drive power.

[0097] Through the above torque analysis during the clearance elimination process, the meshing state of the opposite side tooth surfaces can be extracted according to the typical meshing conditions of the large gear and the small gear (such as Figure 5 (a), 6(a), state A), meshing state of the same side tooth surface (such as Figure 5 (c), 6(c), state B), tooth surface engagement switching state (such as Figure 5 (b), 6(b), state C). The meshing of the tooth surfaces on the same side includes two situations: forward tooth surface meshing and reverse tooth surface meshing. Here, the forward meshing state of the same side is referred to as the forward state B, and the reverse meshing state of the same side is referred to as the reverse state B. The tooth surface meshing switching state includes forward tooth surface meshing switching and reverse tooth surface meshing switching. Here, the forward tooth surface meshing switching state is referred to as the forward state C, and the reverse tooth surface meshing switching state is referred to as the reverse state C. Therefore, the backlash elimination process can be described as "state A", "forward state B", "reverse state B", "forward state C", and "reverse state C". The entire backlash elimination process consists of several processes that maintain the state.

[0098] Comprehensively examining the entire process of the system from rest, forward acceleration, uniform motion, deceleration, reverse acceleration, uniform motion, deceleration and then to rest, it can be described according to the above states:

[0099] Free static state: The dual motors are not enabled and no force is applied to the large gear.

[0100] State A: The master and slave motors output bias torques of equal magnitude and opposite directions to eliminate the backlash, and the large gear is stationary.

[0101] State A: The main motor outputs positive driving torque, the slave motor outputs negative counteracting compensation torque, and the large gear accelerates.

[0102] Forward state C: The main motor outputs a forward driving torque, the slave motor drives the small gear 2 to cross the gap, and the large gear accelerates.

[0103] Forward state B: The master and slave motors jointly output forward driving torque, and the large gear accelerates.

[0104] State A: The master and slave motors are balanced, and the large gear has a uniform speed.

[0105] State B: The slave motor outputs reverse braking torque, the main motor outputs positive counteracting compensation torque, the large gear decelerates and accelerates in the reverse direction.

[0106] Reverse state C: The slave motor outputs reverse braking torque, the main motor drives the small gear 1 to cross the gap, and the large gear accelerates.

[0107] Reverse state B: The master and slave motors jointly output reverse torque, and the large gear accelerates in the reverse direction.

[0108] State A: The master and slave motors reach balance again, and the large gear moves in the opposite direction at a constant speed.

[0109] State A: The main motor outputs positive braking torque, the slave motor outputs negative counteracting compensation torque, and the large gear decelerates.

[0110] Forward state C: The main motor outputs forward braking torque, the slave motor drives small gear 2 to cross the gap, and the large gear decelerates.

[0111] Forward state B: The master and slave motors jointly output deceleration braking torque, and the large gear decelerates.

[0112] State A: The master and slave motors output opposite torques, and the large gear is stationary.

[0113] The above dual-motor backlash elimination process is dynamic, requiring real-time dynamic adjustment of the output torque of the two motors. The system needs to undergo multiple switching transitions between state A, state C, and state B.

[0114] The dual-motor drive system not only needs to consider the operating characteristics of a single motor, but more importantly, it needs to consider the situation when the two motors are linked, control the output torque of the two motors, and make the small gear always mesh with the corresponding tooth surface of the large gear, so as to eliminate the gap and accurately transmit the torque, speed and displacement, and control the motors to share the load.

[0115] This paper adopts a torque compensation control algorithm based on the speed deviation of the dual motors to control the dual motors in real time. The spindle motor adopts the position control mode to achieve precise position control. The speed setting value of the spindle motor is simultaneously input to the speed loop setting of the slave motor. The slave motor performs speed closed-loop control according to the speed command of the spindle motor. The framework diagram of the entire control algorithm is shown in the figure below. Figure 7 shown.

[0116] The spindle position control module is based on the actual position deviation (ie the actual position ε act With reference position ε ref The difference between the two values) is used to calculate the reference speed value n ref The calculated reference speed value n ref At the same time, it is used as the reference of the main axis speed control and the slave axis speed control module. The main axis speed control module is based on the actual speed value n act,M With the given reference speed value n ref The difference between the two is used to calculate the spindle torque current reference value i sqref,scon,M , the slave axis speed control module is based on the actual speed value n act,S With the given reference speed value n ref The difference between the two is used to calculate the slave shaft torque current reference value i sqref,scon,S .

[0117] The calculated master-slave axis torque current reference value is exchanged in real time through the synchronization card. The controller performs PID adjustment on the master-slave axis current by coupling control and compensates for the deviation between the two. Finally, the master axis torque current reference value i after compensation is sqref,scon,M and the slave axis torque current reference value i sqref,scon,S Apply the same magnitude of anti-backlash bias current i sq,bias,M andi sq,bias,S , and ultimately the bias current will be added to the servo control driver for drive control.

[0118] During the entire synchronous backlash elimination process, no matter whether the output directions of the two motors are opposite or the same, even if the output of one motor is exactly zero, the speed of the two motors is always the same, and the speed of the slave motor always follows the speed of the main shaft motor to ensure that the speed of the two small gears is consistent.

[0119] To verify the effectiveness of the control algorithm, two identical Kollmorgen AKM72P servo motors were used to drive two small gears to rotate the large gear. The transmission ratio between the large gear and the small gear was 1:4. The entire system used a Beckhoff C6015 controller as the control core, connected to two servo drives. The main shaft drive was connected to the Ethercat bus for real-time position control, and the slave shaft drive followed the main shaft speed control and performed real-time coupling compensation for current.

[0120] The encoder at the end of the large gear is connected to the second feedback of the spindle drive, making it the feedback source of the position loop. The controller drives the two small gears to drive the large gear to perform sinusoidal swing motion.

[0121] To further measure the position repeatability of the large gear's reciprocating motion, a prism fixture was fixed to the front end of the gear, a calibrated 24-hedron was installed, and the position of the 24-hedron was adjusted. A laser collimator was then used to measure the position repeatability of the large gear's rotation. The host computer interface controlled the large gear to rotate one revolution in the forward direction, then one revolution in the reverse direction, then one revolution in the forward direction, and finally one revolution in the reverse direction. The error readings of the laser collimator were recorded for each of the four groups. The results are shown in Table 1 below.

[0122] Table 1 Laser collimator measurement results

[0123] Experimental procedures Measurement error Forward rotation 360° 5 seconds Reverse rotation 360° 6 seconds Forward rotation 360° 6 seconds Reverse rotation 360° 7 seconds

[0124] The experimental results show that the dual-motor electrical backlash elimination effect is better and can greatly improve the position accuracy of the gear transmission system.

[0125] Reference Figure 5 As shown, further, in combination with the above-mentioned anti-backlash control method for a dual-motor driven gear system, an anti-backlash control device for a dual-motor driven gear system is proposed, comprising:

[0126] A spindle servo motor, which is used to drive the small gear 1 and mesh with the large gear;

[0127] A slave shaft servo motor, the slave shaft servo motor is used to drive the small gear 2 to mesh with the large gear;

[0128] A large gear, which is driven by the small gears driven by the master and slave motors respectively, and is connected to the load for rotation;

[0129] a PID controller, the PID controller interacting with the main axis servo motor and the slave axis servo motor for signal processing and execution of a control algorithm;

[0130] A synchronization card is used for data exchange and synchronization control between the main shaft servo motor and the slave shaft servo motor;

[0131] The encoder can feed back the position and speed information of the gear to the controller in real time.

[0132] To sum up, the advantages of the present invention are: through the coordinated control of dual motors, real-time compensation of torque deviation can be made, which can effectively eliminate the backlash problem in gear transmission and improve the transmission accuracy of the system; the torque coupling compensation control algorithm based on speed deviation can quickly respond to load changes and motion state switching, ensuring that the system remains stable under high dynamic conditions; the torque balance mechanism of the dual motors working together improves the stability and anti-interference ability of the system, and adapts to the precision transmission requirements under complex working conditions; it is not only suitable for gear transmission in turntable servo systems, but can also be extended to other gear transmission systems that require high precision and high dynamic response; it utilizes the existing dual motor drive structure and optimizes the control algorithm without the need for additional mechanical structure or complex hardware support, thereby reducing the cost of system implementation.

[0133] The above shows and describes the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The above embodiments and descriptions merely illustrate the principles of the present invention. Various changes and modifications may be made to the present invention without departing from the spirit and scope of the present invention. Such changes and modifications are intended to fall within the scope of the present invention. The scope of protection claimed by the present invention is defined by the appended claims and their equivalents.

Claims

1. A backlash control method for a dual-motor driven gear system, characterized in that: include: Acquire dual-motor drive gear system information, wherein the dual-motor drive gear system includes main shaft servo motor information, slave shaft servo motor information, large gear information, and small gear information; Based on the dual-motor driven gear system, the reference position information and actual position information of the large gear are obtained; According to the reference position information and the actual position information of the gear, the anti-backlash bias current is obtained based on the torque coupling compensation; According to the anti-backlash bias current, the main axis servo motor current and the slave axis servo motor current are adjusted.

2. The anti-backlash control method of a dual-motor driven gear system according to claim 1, characterized in that: The step of obtaining the anti-backlash bias current based on the torque coupling compensation according to the reference position information of the gearwheel and the actual position information of the gearwheel specifically includes: Obtaining a position deviation value according to the reference position information of the large gear and the actual position information of the large gear; Based on the PID controller, the reference speed value is calculated based on the position deviation value; According to the dual-motor drive gear system information, the actual speed information of the main shaft and the actual speed information of the slave shaft are obtained; Obtain the anti-backlash bias current according to the reference speed value, the actual speed information of the master axis, and the actual speed information of the slave axis.

3. The anti-backlash control method of a dual-motor driven gear system according to claim 2, characterized in that: The step of obtaining the anti-backlash bias current according to the reference speed value, the actual speed information of the main axis, and the actual speed information of the slave axis specifically includes: The difference between the reference speed value and the actual spindle speed is used as the spindle speed deviation value; The difference between the reference speed value and the actual speed of the slave axis is used as the slave axis speed deviation value; According to the main shaft speed deviation value and the slave shaft speed deviation value, based on the PID controller, the main shaft torque current reference value and the slave shaft torque current reference value are calculated respectively; According to the spindle torque current reference value, the spindle anti-backlash bias current is added to the spindle torque current to obtain the spindle motor current information; According to the slave axis torque current reference value, the master axis anti-backlash bias current is added to the slave axis torque current to obtain the slave axis motor current information; Based on the torque balance analysis, the main shaft motor current and the slave shaft motor current are adjusted to obtain the anti-backlash bias current.

4. The anti-backlash control method of a dual-motor driven gear system according to claim 3, characterized in that: The method of adjusting the main shaft motor current and the slave shaft motor current based on the torque balance analysis to obtain the anti-backlash bias current specifically includes: Obtain the spindle torque according to the spindle motor current; Obtain the slave shaft torque according to the slave shaft motor current; The main shaft motor current and the slave shaft motor current are adjusted until the main shaft torque and the slave shaft torque are balanced to obtain the anti-backlash bias current.

5. A backlash control device for a dual-motor driven gear system, used to implement the analysis method according to any one of claims 1 to 4, characterized in that: include: A spindle servo motor, which is used to drive the small gear 1 and mesh with the large gear; A slave shaft servo motor, the slave shaft servo motor is used to drive the small gear 2 to mesh with the large gear; A large gear, which is driven by the small gears driven by the master and slave motors respectively, and is connected to the load for rotation; a PID controller, the PID controller interacting with the main axis servo motor and the slave axis servo motor for signal processing and execution of a control algorithm; A synchronization card is used for data exchange and synchronization control between the main shaft servo motor and the slave shaft servo motor; The encoder provides real-time feedback of the position and speed information of the gear to the controller.

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