CN-121990426-A - Cable management system and control method for electric excavator

CN121990426ACN 121990426 ACN121990426 ACN 121990426ACN-121990426-A

Abstract

The invention discloses a cable management system and a control method of an electric excavator, which belong to the technical field of engineering machinery dynamoelectric, wherein the system comprises an excavator controller, left and right travelling encoders, a tension detection device, an insulation detection module and a horizontally installed cable drum, and the drum adopts a three-pivot installation and conical shield structure and is suitable for a small space of a small excavator. The control method comprises the steps of executing double encoder speed fusion in a fixed period, obtaining equivalent translation speed and rotation angular speed, generating feedforward torque by combining dynamic feedforward compensation, realizing self-adaptive synchronous control through tension closed loop and walking speed prediction, preferentially executing protection action when tension is out of limit, and simultaneously fusing data such as insulation, tension, length and the like to realize cable health diagnosis and multistage early warning. The invention solves the problems of inaccurate speed reference, poor dynamic response, easy breaking and rolling of cables and the like of the tracked vehicle, realizes unmanned retraction under all working conditions, and improves the reliability and safety of the system.

Inventors

WANG FENG
HU SHIQIANG
RUAN JILIAN
LI BIN
ZHENG YANG
CHEN YUNQIANG
FANG KANGNING
LIU LIANG
LI ZHIPENG
He Xiangdai
PENG BINGKANG
WANG WANWAN
FU GUISHAN
WANG RANRAN

Assignees

徐州徐工矿业机械有限公司

Dates

Publication Date: 20260508
Application Date: 20260403

Claims (10)

1. The cable management system for the electric excavator is characterized by comprising an excavator controller, an operating mechanism, an insulation detection module, a left walking encoder, a right walking encoder, a cable drum and a tension detection device; the cable drum comprises a drum motor, a mounting support, a cable guiding frame, a rotary support, a cable reel, a shield, a current collector and an electric cabinet; the left walking encoder and the right walking encoder are respectively arranged at left and right crawler driving wheels of the excavator and are used for collecting the linear speeds of the left and right crawler; the tension detection device is arranged at the guide roller of the cable guide frame and is used for detecting real-time tension of the cable; the insulation detection module is used for monitoring the insulation resistance of the cable; The digging machine controller is communicated with the winding drum controller through a CAN bus, and the winding drum controller is connected with a left walking encoder, a right walking encoder, a tension detection device, an insulation detection module, a winding drum motor and a winding drum encoder; The winding drum controller is configured to execute a double-encoder fusion algorithm, a dynamic feedforward compensation algorithm, a self-adaptive tension closed-loop control algorithm and a walking speed prediction algorithm, so that the synchronous cable winding and unwinding speed and the full walking working condition of the excavator are realized, and the health diagnosis and safety protection of the cable are carried out.
2. The electric excavator electrical management system of claim 1 wherein the cable reels are horizontally mounted, empty and full reel proximity switches are provided on the inside and outside of the reels, and reel encoders are provided on the reel shafts for measuring the speed of the cables, the length of the cables, and the number of windings.
3. The electric excavator electrical management system of claim 1 wherein the cable drum mounting bracket is of a three-pivot construction and is fixedly connected to the excavator truck H frame and the left and right stringers.
4. The electric power shovel electrical management system according to claim 1, wherein the shield is of a tapered configuration for preventing debris from entering the interior of the spool.
5. The electric power management system of claim 1, wherein the current collector is configured to transmit power and signals during rotation of the reel via a brush and slip ring configuration.
6. A cable management control method for an electric excavator, applied to the system of any one of claims 1 to 5, comprising the steps of: Periodically triggering, namely running a control algorithm at a fixed high-frequency control period; the double encoder speed fusion comprises the steps of collecting left and right track linear speeds V_left and V_right in real time, and calculating equivalent translational speeds V_com= (V_left+V_right)/2 and rotational angular speeds omega= (V_right-V_left)/L, wherein L is the track center distance; reading left and right track encoders in real time, and executing double encoder fusion calculation: Calculating the equivalent translation speed of the mass center of the excavator, wherein V_com= (V_left+V_right)/2; calculating the rotation angular speed of the excavator, wherein omega= (V_right-V_left)/L, and L is the center distance of the crawler; dynamic feedforward compensation, namely differentiating V_com and omega to obtain acceleration, calculating feedforward torque T_ff=K_ff_a, and calculating a_com+K_ff_alpha, and superposing the feedforward torque T_ff=K_ff_a, the first and second alpha and the third alpha to the torque command of the spool motor; The speed loop control, namely, taking the speed of a reel encoder as feedback, superposing a walking prediction speed signal delta S and generating a basic torque T_speed; Tension closed loop protection, namely detecting the cable tension F_tension in real time, comparing the cable tension F_tension with a safety threshold value F_min and F_max, and outputting a compensation torque T_tension when the cable tension is out of limit; And (3) torque synthesis, namely superposing T_ff, T_speed and T_tension vectors to obtain a final torque command T_cmd, and driving a reel motor to finish cable winding and unwinding.
7. The electric excavator cable management control method of claim 6 wherein, The walking prediction speed signal delta S is obtained by short-time prediction of the excavator controller according to the control mechanism instruction and the speed power mapping model.
8. The electric excavator cable management control method of claim 6 wherein the tension is: When F_tension is in the safety range, the system works mainly on a speed ring, and T_tension is zero; when the F_tension is detected to rise sharply and approach F_max, the T_tension rapidly becomes a negative value, and the drum motor is instructed to accelerate the cable laying, so that over-pulling is prevented; when the F_tension is detected to be suddenly reduced and approaches F_min, T_tension is quickly changed into a positive value, and the drum motor is instructed to accelerate the cable take-up, so that the slack rolling is prevented.
9. The electric excavator cable management control method of claim 6 further comprising the step of cable health monitoring: Collecting insulation resistance, tension, cable length and operation history data in real time, and carrying out multisource information fusion diagnosis; The insulation resistance suddenly drops and the tension exceeds the limit, so that mechanical damage is judged, and primary emergency stop is triggered; The insulation resistance slowly drops and has no tension abnormality, the aging/soaking is judged, and the secondary early warning is triggered; and establishing a life model based on the accumulated retraction times, the bending radius and the working time, and triggering three-level prevention prompt.
10. The electric excavator cable management control method of claim 6 wherein the tension loop control priority is higher than the speed loop and the out of limit tension compensation torque overrides the speed loop command.

Description

Cable management system and control method for electric excavator Technical Field The invention relates to the technical field of engineering machinery dynamoelization, in particular to an electric excavator cable management system and a control method. Background Along with the continuous improvement of environmental protection requirements, engineering machinery electrodynamic technology becomes an important development direction for achieving the 'double carbon' target, an electric excavator is usually powered by an external cable to ensure continuous operation, and a cable drum automatic winding and unwinding system is a core component for ensuring equipment moving operation. The existing cable drum control system generally adopts a simple speed following or moment balancing principle, and has the following technical defects: 1. the speed sensing standard is not uniform, the crawler excavator has no accurate speed standard during acceleration and deceleration, sudden stop and turning, and the synchronous control precision is poor; 2. The dynamic response is poor, mostly lag feedback control is adopted, transient working conditions such as start-stop, acceleration and deceleration, sharp turning and the like cannot be adapted, and cable pulling, loosening, breaking and rolling risks easily occur; 3. the control dimension is single, only the speed or only the moment is controlled, the coordination capacity of the multivariable working conditions is weak, and the system robustness is poor; the winding drum has a complex structure and large occupied space, is not suitable for a small excavator, and lacks the functions of cable health diagnosis and complex working condition active protection. The full-automatic variable frequency cable device disclosed in the patent CN119774387A adopts a plurality of frequency converters to respectively control a plurality of motors, has a complex structure and large installation space requirement, can not solve the problem of high-precision synchronization of turning, and lacks of cable rolling prevention and health monitoring. Therefore, a miniaturized solution integrating full-working-condition unmanned operation, high dynamic performance synchronous following and multi-dimensional safety protection into a whole is urgently needed, so as to meet the unmanned full-automatic management requirements of cables of engineering machinery such as various excavators in the moving process. Disclosure of Invention The invention overcomes the defects of the prior art, provides a cable management system and a control method for an electric excavator, realizes accurate synchronization of cable winding and unwinding under all working conditions of a crawler excavator, self-adaptive protection of tension and intelligent diagnosis of cable health, and meets the requirements of miniaturized installation and reliable operation of complex construction sites. In order to achieve the aim, the invention adopts the technical scheme that the cable management system of the electric excavator comprises an excavator controller, an operating mechanism, an insulation detection module, a left walking encoder, a right walking encoder, a cable drum and a tension detection device; the cable drum comprises a drum motor, a mounting support, a cable guiding frame, a rotary support, a cable reel, a shield, a current collector and an electric cabinet; The left walking encoder and the right walking encoder are respectively arranged at left and right crawler belt driving wheels of the excavator, and the left and right crawler belt linear speeds V_left and V_right are collected in real time. The tension detection device is arranged at the guide roller of the cable guide frame and adopts a stress sheet type sensor to detect the real-time tension F_tension of the cable. And the insulation detection module adopts an unbalanced bridge method to monitor the insulation resistance of the cable bus to the ground in real time. The drum controller is connected with the left walking encoder, the right walking encoder, the tension detection device, the insulation detection module, the drum motor and the drum encoder, and executes a double encoder fusion algorithm, a dynamic feedforward compensation algorithm, a self-adaptive tension closed-loop control algorithm and a walking speed prediction algorithm to realize the synchronization of the cable winding and unwinding and the full working condition of the excavator walking and complete the health diagnosis and multistage safety protection of the cable. Further, the cable reel is horizontally installed, empty reel and full reel proximity switches are arranged on the inner side and the outer side of the reel, and a reel encoder is arranged at a reel rotating shaft and used for measuring the cable reeling speed, the cable reeling and unreeling length, the winding number and the winding position. Further, the cable drum installing support adopts three fulcrum structures, is fixed