Dual self-driving permanent magnet outer rotor elevator and synchronous control method thereof

Abstract

A double self-driven permanent magnet outer rotor elevator and a synchronous control method thereof, comprising two outer rotor permanent magnet drum assemblies, a PLC synchronous controller and a fault-tolerant linkage device; each outer rotor permanent magnet drum assembly comprises coaxially arranged left drum assembly and right drum assembly, and the left drum assembly and the right drum assembly are in a symmetrical structure; when the left drum assembly and the right drum assembly are normal, there is no rigid connection between the left drum assembly and the right drum assembly, and the PLC synchronous controller controls the synchronous rotation of the left drum assembly and the right drum assembly; when any drum assembly fails, the two drum assemblies are rigidly connected through the fault-tolerant linkage device, the PLC synchronous controller controls the rotation of the normal drum assembly, and the normal drum assembly drives the synchronous rotation of the failed drum assembly. The present application proposes a low-power-consumption and high-reliability permanent magnet driven electric shovel elevator, which has the advantages of no high-speed shaft and mechanical sliding friction pair and fewer transmission links, and realizes flexible synchronous control operation of double machines.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of mine hoisting equipment, and in particular relates to a double self-driving permanent magnet outer rotor hoist and a synchronous control method thereof. BACKGROUND

[0002] Steel rope hoisting systems are widely used in heavy load hoisting occasions in the mining, port, metallurgy and construction industries. The existing hoisting systems are generally driven by asynchronous motors + gear reducers to drive the winding drum to hoist the steel wire rope. During operation, frequent forward and reverse rotation is required for start and stop. The asynchronous motor often works in the low speed zone and under the conditions of no load and under load, and has low efficiency and power factor, small torque and large power consumption. At the same time, the gear transmission system frequently under the working environment of heavy load impact has many faults and high maintenance requirements.

[0003] A large-distance multi-rope traction hoisting system and a hoisting method of China University of Mining and Technology with application number 202110321942.X balance the different torques of the four main shafts corresponding to the side drums through the transmission of the driving torque between the main shafts of different direct drive units by the transmission gear and the intermediate gear, balance the different torques of the four drums corresponding to the four main shafts through the revolution and rotation of the planetary bevel gears, and finally ensure that the driving forces output by the four drums that pull the same lifting container are equal, ensuring that the tension of each lifting rope is equal, and achieving the purpose of balancing the tension of each lifting rope of the hoisting system. However, the hoisting system has too many gear transmission links, resulting in large efficiency loss.

[0004] The permanent magnet outer rotor hoist patent of Taiyuan University of Technology with application number CN201911348950.2 provides an outer rotor permanent magnet drive hoist with short-distance distributed windings and fractional slots without a transmission shaft. The permanent magnets are fixed by fixing blocks to prevent falling off, have no high-speed shaft and mechanical friction pair, have high power factor, and have small maintenance requirements.

[0005] However, the power of a single permanent magnet hoist is limited. Directly increasing the axial span of the permanent magnet drum will cause poor heat dissipation conditions inside the motor, and the long shaft motor will deform under heavy load, causing the air gap magnetic field to be disturbed and even the structure to be damaged. Moreover, a single permanent magnet self-driving outer rotor hoist still has the risk of demagnetization and falling accidents when working in a heavy load and frequent start-stop impact environment for a long time. SUMMARY

[0006] To solve the problems in the prior art, the application provides a double self-driving permanent magnet outer rotor hoist for heavy load working environment and a synchronous control method thereof, realizes a high-power heavy load, low-power consumption and high-reliability permanent magnet drive hoisting equipment, realizes a safe hoisting drive mode without high-speed shaft and mechanical sliding friction pair and with few transmission links, and realizes a master-slave control double-machine flexible synchronous control operation method.

[0007] The application adopts the technical scheme as follows.

[0008] The application provides a double self-driven permanent magnet outer rotor elevator, which can be applied to a lifting device of an electric shovel and comprises a top pulley, a balance pulley, a lifting beam, a bucket, a lifting steel wire rope, a saddle, a bucket handle, a main taut rope, an A-shaped frame, an outer rotor permanent magnet reel assembly, a hoisting arm and a slewing platform, wherein the A-shaped frame is installed on the slewing platform, the outer rotor permanent magnet reel assembly and the hoisting arm are installed on the A-shaped frame, a top end side of the A-shaped frame is connected with one end of the main taut rope, the other end of the main taut rope is connected with the top pulley, the hoisting arm is fixed by the main taut rope on the A-shaped frame, a crown block is installed at a far end of the hoisting arm away from the slewing platform, a saddle is installed on each of left and right sides of the middle part of the hoisting arm, a bucket handle is installed in each of the two saddles, the two bucket handles are connected with the bucket, the lifting steel wire rope is wound on the outer rotor permanent magnet reel assembly, the lifting steel wire rope is connected with the lifting beam after passing through the top pulley and the balance pulley, the lifting beam is connected with the bucket, the outer rotor permanent magnet reel assembly is rotated to wind or loosen the lifting steel wire rope, so that the bucket is lifted or lowered, and a pushing motor pushes the two bucket handles to be inserted into or withdrawn from the saddles at the same time.

[0009] The elevator further comprises a PLC synchronous controller and a fault-tolerant linkage device.

[0010] The outer rotor permanent magnet reel assembly comprises a first outer rotor permanent magnet reel assembly and a second outer rotor permanent magnet reel assembly, and the two outer rotor permanent magnet reel assemblies are of the same structure, each outer rotor permanent magnet reel assembly comprises coaxially and side-by-side arranged left and right reel assemblies, and the left and right reel assemblies are of a symmetrical structure.

[0011] When the left and right reel assemblies are normal, there is no rigid connection between the left and right reel assemblies, the PLC synchronous controller controls the left and right reel assemblies to rotate synchronously, when any reel assembly is faulty, the two reel assemblies are rigidly connected through the fault-tolerant linkage device, the PLC synchronous controller controls the normal reel assembly to rotate, and the normal reel assembly drives the faulty reel assembly to rotate synchronously.

[0012] The left reel assembly comprises an outer rotor, an inner stator and an encoder, the outer rotor comprises a web plate, a permanent magnet, a bearing and a left reel, the web plate is installed on the bearing, the permanent magnet is installed on a side of the web plate facing the left reel, and the left reel is internally attached with a permanent magnet, the inner stator comprises a main shaft support frame, a main shaft, a brake, a brake disc and a stator winding, the main shaft is installed on the main shaft support frame, the main shaft is provided with the stator winding, the brake and the brake disc, and the encoder is used for collecting position signals and speed signals of the left reel in real time and transmitting the signals to the PLC synchronous controller.

[0013] The right winding drum assembly comprises an outer rotor, an inner stator and an encoder; the outer rotor comprises a web, a permanent magnet, a bearing and a right winding drum; the web is mounted on the bearing, the permanent magnet is mounted on the side of the web facing the right winding drum, and the permanent magnet is attached to the inside of the right winding drum; the inner stator comprises a main shaft support frame, a main shaft, a brake, a brake disc and a stator winding, wherein the main shaft is mounted on the main shaft support frame, and the stator winding, the brake and the brake disc are mounted on the main shaft; the encoder is used to collect the position signal and the speed signal of the right winding drum in real time and transmit them to the PLC synchronous controller.

[0014] Preferably, the inclination direction of the rope groove on the left winding drum is opposite to the inclination direction of the rope groove on the right winding drum.

[0015] Preferably, the top pulley comprises a top left pulley and a top right pulley arranged coaxially and side by side; the center axes of the top left pulley and the top right pulley are parallel to the center axes of the left winding drum and the right winding drum and perpendicular to the center axis of the balance pulley; the top left pulley is provided with a left rope groove and a right rope groove, the top right pulley is provided with a left rope groove and a right rope groove, and the balance pulley is provided with a front rope groove and a rear rope groove, wherein the rear rope groove is close to the outer rotor permanent magnet winding drum assembly; the lifting steel wire rope comprises a left lifting steel wire rope and a right lifting steel wire rope.

[0016] The left lifting steel wire rope wound on the left winding drum passes through the left rope groove of the top left pulley, the front rope groove of the balance pulley and the left rope groove of the top right pulley in sequence and is then wound on the right winding drum; the right lifting steel wire rope wound on the left winding drum passes through the right rope groove of the top left pulley, the rear rope groove of the balance pulley and the right rope groove of the top right pulley in sequence and is then wound on the right winding drum.

[0017] The balance pulley is used to control the same load of the left winding drum assembly and the right winding drum assembly.

[0018] Preferably, the left winding drum assembly is equipped with a first variable frequency driver arranged in a first variable frequency driver cabinet; the right winding drum assembly is equipped with a second variable frequency driver arranged in a second variable frequency driver cabinet; and the two variable frequency drivers are controlled by the PLC synchronous controller.

[0019] Preferably, the fault-tolerant linkage device comprises: a pair of reel gears, a fault-tolerant linkage structure; wherein the fault-tolerant linkage structure is installed on the slewing platform, one reel gear is installed on the main shaft of the left reel assembly and close to the right reel assembly, and the other reel gear is installed on the main shaft of the right reel assembly and close to the left reel assembly; the fault-tolerant linkage structure comprises: a pair of linkage sliding gears, a spline shaft, a pair of linkage yokes, a pair of linkage oil cylinders and a pair of support seats; wherein the pair of support seats are installed on the slewing platform, one linkage oil cylinder is installed on each support seat, the piston of each linkage oil cylinder is connected with one linkage yoke, each linkage yoke is connected with one linkage sliding gear, the spline shaft is installed on the two support seats, and the pair of linkage sliding gears are installed on the spline shaft and can slide on the spline shaft.

[0020] Preferably, during the movement of the lifting appliance, when both reel assemblies are normal, the linkage oil cylinders control the linkage yokes to place the linkage sliding gears at the edge positions of the two ends of the spline shaft, and lock the linkage oil cylinders, at this time, the linkage sliding gears are not engaged with the reel gears, and the two reel assemblies are not rigidly connected;

[0021] During the movement of the lifting appliance, when the encoder of any reel assembly outputs a reel fault signal to the PLC synchronous controller, the PLC synchronous controller simultaneously outputs a brake signal to the first variable frequency driver and the second variable frequency driver; under the control of the first variable frequency driver and the second variable frequency driver, the brake and the brake disc of the left reel assembly and the right reel assembly cooperate to realize braking; the PLC synchronous controller simultaneously sends a start signal to the hydraulic control systems of the two linkage oil cylinders, controls the piston to extend out of the linkage oil cylinder, and drives the linkage yoke to move the linkage sliding gear, so that the linkage sliding gear is engaged with the corresponding reel gear, thereby realizing the rigid connection between the left reel assembly and the right reel assembly; when the PLC synchronous controller simultaneously outputs a start signal to the first variable frequency driver and the second variable frequency driver, the non-fault reel assembly drives the fault reel assembly to rotate synchronously.

[0022] The application also provides a control method of the double self-driven permanent magnet outer rotor elevator, comprising:

[0023] Step 1, detecting whether the left reel assembly and the right reel assembly exist faults; if not, entering step 2, if yes, entering step 3;

[0024] Step 2: The encoder of the left drum assembly collects the left drum position signal and speed signal and transmits them to the PLC synchronization controller. The encoder of the right drum assembly collects the right drum position signal and speed signal and transmits them to the PLC synchronization controller. The PLC synchronization controller obtains the synchronization control signal of the left drum assembly and the right drum assembly based on the master-slave control system. The PLC synchronization controller sends the synchronization control signal of the left drum assembly and the right drum assembly to the first variable frequency drive and the second variable frequency drive, respectively, to synchronously control the dual self-driven permanent magnet outer rotor hoist.

[0025] Step 3, the PLC synchronous controller sends a braking signal to the first variable frequency drive and the second variable frequency drive at the same time, and at the same time the PLC synchronous controller controls the linkage sliding gear to engage with the corresponding reel gear, and the non-fault reel assembly drives the faulty reel assembly to rotate, so as to synchronously control the dual self-driven permanent magnet outer rotor hoist.

[0026] Preferably, in step 2, the left reel assembly is used as a main motor, the right reel assembly is used as a slave motor, a first variable frequency drive drives the main motor to rotate, and a second variable frequency drive drives the slave motor to rotate, including:

[0027] 1) Get the current position θ1 and target position θ of the main motor ref The first position deviation;

[0028] 2) According to the first position deviation, based on the position loop PI controller of the main motor, the target speed ω of the main motor is obtained ref ;

[0029] 3) Get the current speed ω1 and target speed ω of the main motor ref The first speed deviation Δω1;

[0030] 4) According to the first speed deviation Δω1, the main motor is driven by a field oriented control / direct torque control controller based on the main motor;

[0031] 5) The current position θ1 of the main motor collected in real time by the encoder of the main motor is used as the first input; the difference Δθ between the current position θ1 of the main motor collected in real time by the encoder of the main motor and the current position θ2 of the slave motor collected in real time by the encoder of the slave motor is used as the second input; the speed difference is obtained by the difference Δθ through the PI controller of the slave motor position loop as the third input;

[0032] 6) Based on the first input, the second input and the third input, the parameter k of the PI controller of the slave motor position loop is optimized based on the neural network. p 、k i ;

[0033] 7) According to the difference value Δθ, the target rotating speed ω of the slave motor is obtained based on the optimized position loop PI controller of the slave motor ref′ ;

[0034] 8) The second rotating speed deviation amount Δω2 of the current rotating speed ω2 and the target rotating speed ω of the slave motor is obtained ref′ ;

[0035] 9) According to the second rotating speed deviation amount Δω2, the field-oriented control / direct torque control controller of the slave motor is driven based on the slave motor.

[0036] Preferably, the neural network comprises an input layer, a hidden layer and an output layer; after the first input amount, the second input amount and the third input amount are transmitted from the input layer to the hidden layer, the neural network calculates the output amount of each node in the output layer; based on the current output amount of the neural network, the second rotating speed deviation amount is obtained; when the error of the second rotating speed deviation amount Δω2 and the first rotating speed deviation amount Δω1 does not exceed the limit value, the optimized position loop PI controller of the slave motor is determined based on the current output amount of the neural network; when the error of the second rotating speed deviation amount Δω2 and the first rotating speed deviation amount Δω1 exceeds the limit value, the gradient value of the loss function is optimized as the target, and the parameters of the hidden layer and the input layer are adjusted to determine the optimized position loop PI controller of the slave motor.

[0037] The beneficial effects of the present application at least include that, compared with the prior art, the proposed elevator realizes the safe synchronization of the double machines in normal lifting work and fault working conditions through soft synchronization control and fault-tolerant linkage control. Specifically, two independent drum assemblies drive a bucket to work together without rigid connection, and cooperate with the boom pushing mechanism to complete the shovel, loading and transportation work of the electric shovel; the master-slave soft synchronization control based on neural network self-learning ensures the synchronous lifting of the double drums in normal lifting working conditions, and eliminates the influence of the position error of the two drums after the cycle lifting on the synchronization of the double motors; the fault-tolerant linkage structure is actually a kind of hydraulic control double-drum fault-tolerant linkage device, which can realize the rapid switching of the left drum and the right drum in the rigid connection and separation state (non-rigid connection), ensure that the double drum assemblies can still maintain safe synchronous rotation in the fault working condition of the single drum assembly, and avoid the falling accidents of the lifting container or the lifting tool.

[0038] The application scenario of the proposed double self-driving permanent magnet outer rotor elevator is not limited to the electric shovel working environment, but also includes other heavy load lifting occasions such as mining, metallurgy and construction. BRIEF DESCRIPTION OF DRAWINGS

[0039] Figure 1 The structure diagram of the double self-driving permanent magnet outer rotor elevator proposed by the present application is shown in the figure;

[0040] Figure 2The structure diagram of the double self-driving permanent magnet outer rotor elevator applied to the electric shovel lifting device;

[0041] Figure 1 and 2 The reference signs in the drawings are explained as follows: 101, top pulley; 102, balance pulley; 103, lifting beam; 104, shovel; 105, lifting steel wire rope; 106, saddle; 107, bucket arm; 108, main rope; 109, A-shaped frame; 110, first outer rotor permanent magnet reel assembly; 111, lifting arm; 112, slewing platform; 113, PLC synchronous controller; 114, left variable frequency driver; 115, right variable frequency driver; 116, second outer rotor permanent magnet reel assembly; 117, lifting appliance;

[0042] Figure 3 The sectional structure schematic diagram of the outer rotor permanent magnet reel assembly; the outer rotor permanent magnet reel assembly comprises left reel assembly and right reel assembly arranged coaxially and side by side;

[0043] Figure 3 The reference signs in the drawings are explained as follows:

[0044] 306, left reel; 201, web plate; 202, main shaft support frame; 203, main shaft; 204, brake; 205, brake disc; 206, stator winding; 207, permanent magnet; 208, bearing; 210, encoder;

[0045] Figure 4 The working schematic diagram of the lifting system of the elevator in the application;

[0046] Figure 4 The reference signs in the drawings are explained as follows:

[0047] 301, top left pulley; 302, top right pulley; 102, balance pulley; 304, left side lifting steel wire rope; 305, right side lifting steel wire rope; 306, left reel; 307, right reel;

[0048] Figure 5 The structure principle diagram of the master-slave control system in the embodiment of the application;

[0049] Figure 6 The soft synchronization control block diagram of the left reel assembly and the right reel assembly in the embodiment of the application;

[0050] Figure 7 The structure schematic diagram of the double reel fault-tolerant linkage system of the elevator in the application;

[0051] Figure 7 The reference signs in the drawings are explained as follows:

[0052] 601, spool gear; 602, linkage sliding gear; 603, spline shaft; 604, linkage shift fork; 605, linkage oil cylinder; 606, support seat;

[0053] Figure 8 The control method flow chart of the double self-driving permanent magnet outer rotor elevator in the application. DETAILED DESCRIPTION

[0054] In order to make the objects, technical solutions and advantages of the present application clearer, the technical solutions will be described clearly and completely below with reference to the drawings in the embodiments of the present application. The embodiments described in the present application are only a part of the embodiments of the present application, but not all the embodiments. Based on the spirit of the present application, all the other embodiments obtained by those skilled in the art without any creative work fall within the protection scope of the present application.

[0055] The present application provides a double self-driving permanent magnet outer rotor elevator, which is used in heavy load lifting occasions in mining, port, metallurgy and construction industries. Figure 1 and 2 As shown in the drawings, the elevator comprises a top pulley 101, a balance pulley 102, a lifting beam 103, a shovel 104, a lifting steel wire rope 105, a saddle 106, a bucket handle 107, a main rope 108, an A-shaped frame 109, a first outer rotor permanent magnet spool assembly 110, a hoisting arm 111, a slewing platform 112, a PLC synchronous controller 113, a left variable frequency driver 114, a right variable frequency driver 115, a second outer rotor permanent magnet spool assembly 116 and a lifting tool 117. The first outer rotor permanent magnet spool assembly and the second outer rotor permanent magnet spool assembly are installed on the slewing platform, the top pulley comprises a pair of symmetrical pulleys, the winding method is as shown in Figure 3 , the two ends of the lifting steel wire rope are connected with the first outer rotor permanent magnet spool assembly and the second outer rotor permanent magnet spool assembly respectively and pass through the top pulley, and the middle part passes through the balance pulley on the lifting tool, so that the loads borne by the first outer rotor permanent magnet spool assembly and the second outer rotor permanent magnet spool assembly are balanced and equalized.

[0056] The rotary platform is provided with an A-shaped frame, a first outer rotor permanent magnet winding assembly, a second outer rotor permanent magnet winding assembly and a lifting arm. The top end of the A-shaped frame is connected with one end of a main rope, and the other end of the main rope is connected with a top pulley, so that the lifting arm is fixed by the main rope on the A-shaped frame. The end of the lifting arm away from the rotary platform is provided with the top pulley, and the left and right sides of the middle part of the lifting arm are respectively provided with a saddle. Each saddle is provided with a bucket handle, and the two bucket handles are connected with a bucket. The first outer rotor permanent magnet winding assembly and the second outer rotor permanent magnet winding assembly are both wound with a lifting steel wire rope. The lifting steel wire rope is connected with a lifting beam through the top pulley and a balance pulley. The lifting beam is connected with the bucket. The outer rotor permanent magnet winding assembly lifts or lowers the bucket by winding the lifting steel wire rope. The push motor pushes the two bucket handles to simultaneously insert into or exit from the saddle, so that the electric shovel completes the digging work.

[0057] Specifically, the first outer rotor permanent magnet winding assembly and the second outer rotor permanent magnet winding assembly are the same in structure. Each outer rotor permanent magnet winding assembly comprises coaxially arranged left winding assembly and right winding assembly. The left winding assembly and the right winding assembly are symmetrical structures. When the left winding assembly and the right winding assembly are normal, there is no rigid connection between the left winding assembly and the right winding assembly, and they are in a separated state. As shown in Figure 3 The left winding assembly comprises an outer rotor, an inner stator and an encoder 210. The outer rotor comprises a web plate 201, a permanent magnet 207, a bearing 208 and a left winding 306. The web plate is installed on the bearing, and the permanent magnet is installed on the side of the web plate facing the left winding. The left winding is internally attached with the permanent magnet. The inner stator comprises a main shaft support frame 202, a main shaft 203, a brake 204, a brake disc 205 and a stator winding 206. The main shaft is installed on the main shaft support frame, and the stator winding, the brake and the brake disc are installed on the main shaft. The outer rotor and the inner stator jointly form an outer rotor permanent magnet synchronous motor with a brake function. The encoder is used to collect the position signal and the speed signal of the left winding in real time and transmit them to a PLC synchronous controller.

[0058] Similarly, as shown in Figure 3 and 4 The right winding assembly comprises an outer rotor, an inner stator and an encoder. The outer rotor comprises a web plate, a permanent magnet, a bearing and a right winding 307. The web plate is installed on the bearing, and the permanent magnet is installed on the side of the web plate facing the right winding. The right winding is internally attached with the permanent magnet. The inner stator comprises a main shaft support frame, a main shaft, a brake, a brake disc and a stator winding. The main shaft is installed on the main shaft support frame, and the stator winding, the brake and the brake disc are installed on the main shaft. The outer rotor and the inner stator jointly form an outer rotor permanent magnet synchronous motor with a brake function. The encoder is used to collect the position signal and the speed signal of the right winding in real time and transmit them to a PLC synchronous controller.

[0059] Further, the inclined direction of the rope groove on the left winding drum is opposite to that of the rope groove on the right winding drum. Figure 3 As shown in the figure, the left winding drum and the right winding drum are placed side by side, and the rope groove angles of the two are both inward, which eliminates the traditional gear transmission system, improves the transmission efficiency, improves the reliability of the transmission system, and reduces the maintenance workload. In the case where space is not allowed, the two winding drums can be arranged in front of and behind each other or staggered.

[0060] The lifting machine provided by the application adopts a left winding drum assembly and a right winding drum assembly to form an outer rotor permanent magnet driving winding drum assembly, and the left winding drum assembly and the right winding drum assembly are used as driving motors of the electric shovel lifting system. Compared with a long-span single permanent magnet winding drum lifting device with high length-diameter ratio and two end supports, the axial span of the left winding drum assembly and the right winding drum assembly is short and has an independent support structure, so that the stress condition is good, and unacceptable distortion and motor air gap disorder will not occur due to high length-diameter ratio and large span. The design structure of the double-shaft small span optimizes the speed reduction brake mechanism, directly removes the speed reduction mechanism to reduce the heat dissipation requirement, so that the heat dissipation environment is good, and the problem that the outer rotor motor cannot normally operate or even the structure is damaged due to poor heat dissipation condition of the overlong high-power motor during operation is avoided. Therefore, the total lifting force of the lifting machine provided by the application exceeds 2000 kN, and the operation reliability of the lifting machine is significantly improved.

[0061] The lifting system in the lifting machine provided by the application includes a top pulley, a balance pulley, a lifting steel wire rope and an outer rotor permanent magnet winding drum assembly.

[0062] Specifically, as Figure 4As shown, the top pulley comprises: top left pulley 301 and top right pulley 302 arranged coaxially and side by side; the center axes of the top left pulley and the top right pulley are parallel to the center axes of the left drum and the right drum, and are perpendicular to the center axis of the balance pulley. The top left pulley is provided with left and right rope grooves, the top right pulley is provided with left and right rope grooves, and the balance pulley is provided with front and rear rope grooves, wherein the rear rope groove is close to the outer rotor permanent magnet drum assembly. The hoisting steel wire rope comprises: left side hoisting steel wire rope 304 and right side hoisting steel wire rope 305. The left side hoisting steel wire rope wound on the left drum passes through the left side rope groove of the top left pulley, the front rope groove of the balance pulley and the left rope groove of the top right pulley in sequence, and is then wound on the right drum; the right side hoisting steel wire rope wound on the left drum passes through the right rope groove of the top left pulley, the rear rope groove of the balance pulley and the right rope groove of the top right pulley in sequence, and is then wound on the right drum. The winding mode of the hoisting system proposed by the application has two steel wire ropes in total, which are wound in four rope grooves of the top left pulley and the top right pulley from the balance pulley, and then return to the inside of the drum and are finally fixed on the outside of the drum. The rope grooves on the two drums have an inclination angle towards the lifting arm direction, the balance pulley is used to balance the tension on the two side hoisting steel wire ropes, the left drum winds the left ends of the two steel wire ropes, and the right drum winds the right ends of the two steel wire ropes.

[0063] The left drum assembly is equipped with a first variable frequency driver arranged in a first variable frequency driver cabinet; the right drum assembly is equipped with a second variable frequency driver arranged in a second variable frequency driver cabinet; both variable frequency drivers are controlled by a PLC synchronous controller.

[0064] In a non-limiting preferred embodiment, the motor parameters of the left drum assembly and the right drum assembly are the same, the winding phases are the same, and therefore the driving torque, the load torque and the friction torque are also the same, satisfying the following relationship:

[0065]

[0066] In the formula, T e is the driving torque, T L is the load torque, T f is the friction torque, J is the moment of inertia, is the winding phase.

[0067] The left drum assembly and the right drum assembly can basically move synchronously under open loop synchronization, but due to differences in manufacturing and assembly precision, load fluctuation, environmental factors and the like, it is inevitable to cause asynchronization between the double shafts of the left drum assembly and the right drum assembly, especially in the electric shovel hoisting mechanism, the frequent hoisting and lowering cycles will accumulate position errors, and therefore the errors of speed and position need to be controlled.

[0068] The soft synchronization control flow is as follows: Figure 5As shown, including: balance pulley for control left and right winding drum assembly load the same, left winding drum assembly encoder left winding drum assembly position signal and speed signal transmission to PLC synchronization controller, while the right winding drum assembly encoder right winding drum assembly position signal and speed signal transmission to PLC synchronization controller; PLC synchronization controller sends control signal to the first variable frequency drive and second variable frequency drive; in non-limiting preferred embodiment, with left winding drum assembly as the master motor, with right winding drum assembly as the slave motor, the first variable frequency drive drive master motor rotation, while the second variable frequency drive drive slave motor rotation.

[0069] PLC synchronization controller includes master-slave control system, based on master-slave control system to realize soft synchronization control, in non-limiting preferred embodiment, the soft synchronization control of left winding drum assembly and right winding drum assembly as shown in Figure 6 As shown, including:

[0070] 1), the current position θ1and target position θ ref of the master motor are obtained;

[0071] 2), according to the first position deviation, based on the position loop PI controller of the master motor, the target speed ω ref of the master motor is obtained;

[0072] 3), the first speed deviation Δω1of the current speed ω1and target speed ω ref of the master motor is obtained;

[0073] 4), according to the first speed deviation Δω1, based on the FOC / DTC (field oriented control / direct torque control) controller of the master motor, to drive the master motor PMSM1;

[0074] 5), the current position θ1of the master motor collected by the encoder of the master motor in real time as the first input; the difference Δθ between the current position θ1of the master motor collected by the encoder of the master motor in real time and the current position θ2of the slave motor collected by the encoder of the slave motor in real time, as the second input; the difference Δθ is converted into speed difference by the slave motor position loop PI controller, as the third input;

[0075] 7), according to the first input, the second input and the third input, based on neural network, the parameters k p , k i of the slave motor position loop PI controller are optimized;

[0076] 7), according to the difference Δθ, based on the optimized position loop PI controller of the slave motor, the target speed ω ref′ of the slave motor is obtained;

[0077] 8), the current speed ω2and target speed ωref′ a second rotational speed deviation amount Δω2;

[0078] 9) based on the second rotational speed deviation amount Δω2, a FOC / DTC (field oriented control / direct torque control) controller of the slave motor PMSM2 is driven.

[0079] Further, the neural network comprises an input layer, a hidden layer and an output layer; after the first input amount, the second input amount and the third input amount are transmitted from the input layer to the hidden layer, the neural network calculates the output amount of each node in the output layer; based on the current output amount of the neural network, the second rotational speed deviation amount is obtained; when the error between the second rotational speed deviation amount Δω2 and the first rotational speed deviation amount Δω1 does not exceed the limit value, the optimized position loop PI controller of the slave motor is determined according to the current output amount of the neural network; when the error between the second rotational speed deviation amount Δω2 and the first rotational speed deviation amount Δω1 exceeds the limit value, the optimized position loop PI controller of the slave motor is determined by taking the optimal gradient value of the loss function as the target and adjusting the parameters of the hidden layer and the input layer; in the non-restrictive preferred embodiment, the first rotational speed deviation amount Δω1 and the second rotational speed deviation amount Δω2 are equal to the rotational speed deviation amount Δω, and the preferred value of the limit value is 0.

[0080] The master-slave control system provided by the application realizes adaptive master-slave position soft synchronization control, and under the condition that the load of the left drum assembly and the right drum assembly is balanced by the pulley, not only can the rotational speed of the left drum assembly and the right drum assembly be ensured to be the same to improve the stability of the bucket movement by the synchronous movement of the double shafts, but also the accumulated position error in the lifting and lowering cycle can be adaptively released.

[0081] The above-mentioned synchronization control is realized under the premise that the left drum assembly and the right drum assembly are normal. Since the working environment of the power shovel is harsh, when any drum assembly appears a demagnetization fault, a bucket falling accident will be caused. In order to avoid the expansion of the accident, a fault-tolerant linkage control of the double drum assemblies is needed. Therefore, as shown in Figure 7As shown, the elevator proposed by the present invention also includes a fault-tolerant linkage device, which includes: a pair of drum gears 601 and a fault-tolerant linkage structure; wherein, the fault-tolerant linkage structure is installed on the rotary platform, one drum gear is installed on the main shaft of the left drum assembly and is close to the right drum assembly, and the other drum gear is installed on the main shaft of the right drum assembly and is close to the left drum assembly; the fault-tolerant linkage structure includes: a pair of linkage sliding gears 602, a spline shaft 603, a pair of linkage forks 604, a pair of linkage cylinders 605 and a pair of support seats 606; wherein, a pair of support seats are installed on the rotary platform, each support seat is installed with a linkage cylinder, the piston of each linkage cylinder is connected to a linkage fork, each linkage fork is connected to a linkage sliding gear, spline shafts are installed on the two support seats, and a pair of linkage sliding gears are installed on the spline shaft and can slide on the spline shaft.

[0082] During the movement of the bucket, when both drum assemblies are normal, the linkage cylinder controls the linkage fork to place the linkage sliding gear at the edge positions of the two ends of the spline shaft and locks the linkage cylinder. At this time, the linkage sliding gear and the drum gear are not engaged, and the two drum assemblies have no rigid connection and can operate independently.

[0083] During the movement of the bucket, when the encoder of any drum assembly outputs a drum fault signal to the PLC synchronous controller, the PLC synchronous controller simultaneously outputs a braking signal to the first variable frequency drive and the second variable frequency drive; under the respective control of the first variable frequency drive and the second variable frequency drive, the brakes and brake discs of the left drum assembly and the right drum assembly cooperate to achieve braking; the PLC synchronous controller simultaneously sends a start signal to the hydraulic control systems of the two linked cylinders, controlling the piston to extend from the linked cylinder, and the piston drives the linked shift fork to move the linked sliding gear, so that the linked sliding gear engages with the corresponding drum gear, thereby achieving a rigid connection between the left drum assembly and the right drum assembly; when the PLC synchronous controller simultaneously outputs a start signal to the first variable frequency drive and the second variable frequency drive, the non-faulty drum assembly drives the faulty drum assembly to rotate synchronously, thereby achieving synchronous rotation of the two drum assemblies, safely completing the current lowering operation, and avoiding the occurrence of bucket falling accidents.

[0084] In the elevator, the components that must rotate synchronously in the two drum assemblies include the web, the brake disc, the permanent magnet, the left drum and the right drum; the permanent magnets are attached to the inner walls of the left drum and the right drum, and the electromagnetic characteristics of the permanent magnets when rotating are used as the criterion for judging whether the two drum assemblies rotate synchronously; the permanent magnets that are magnetized in the radial direction are installed on the inner walls of the left drum and the right drum, the stator winding is installed on the core of the main shaft, the power line is connected to the stator winding through the hole in the main shaft to provide current to the left drum assembly and the right drum assembly, the square shafts at the two ends of the main shaft are installed on the main shaft support frame to limit the rotation of the main shaft, and the left drum assembly and the right drum assembly are supported by the bearings between the web and the main shaft and rotate under the action of the rotating magnetic field formed by the stator winding. The left drum assembly and the right drum assembly can have the characteristics of smooth start at ultra-low frequency, operation at low speed and large torque, and high motor efficiency.

[0085] In the elevator, soft synchronization control and fault-tolerant linkage control are used to realize the safe synchronization of the two machines in normal digging and fault conditions. Specifically, the two independent drum assemblies jointly drive a bucket to work without rigid connection, and cooperate with the boom pushing mechanism to complete the digging, loading and transporting operations of the electric shovel; the master-slave soft synchronization control based on neural network self-learning ensures the synchronous lifting of the two drums in normal digging conditions, and eliminates the influence of the position error of the two drums after the cyclic lifting on the synchronization of the two motors; the fault-tolerant linkage structure is actually a hydraulic control double-drum fault-tolerant linkage device, which can realize the rapid switching of the left drum and the right drum in the rigid connection and separation state (non-rigid connection), ensure that the double-drum assembly can still maintain safe synchronous rotation in single-drum assembly fault conditions, and avoid bucket falling accidents.

[0086] The elevator has no transmission shaft and mechanical sliding friction pair, has the advantages of high power factor, good starting characteristics, simple manufacturing process and easy assembly.

[0087] The application further provides a synchronization control method of the double self-driven permanent magnet outer rotor elevator, which is as shown in the specification and the drawings. Figure 8 , comprising:

[0088] Step 1, detecting whether the left drum assembly and the right drum assembly have faults; if not, entering step 2, if yes, entering step 3;

[0089] Specifically, when the PLC synchronization controller performs the synchronization control of the left drum assembly and the right drum assembly based on the master-slave control system, the rotation speed signals and the current signals of the left drum assembly and the right drum assembly are collected, which are used to detect whether the left drum assembly and the right drum assembly have faults.

[0090] Step 2, the encoder of the left winding drum assembly collects the left winding drum position signal and speed signal and transmits to the PLC synchronous controller, and the encoder of the right winding drum assembly collects the right winding drum position signal and speed signal and transmits to the PLC synchronous controller; the PLC synchronous controller obtains the synchronous control signals of the left winding drum assembly and the right winding drum assembly based on the master-slave control system; the PLC synchronous controller sends the synchronous control signals of the left winding drum assembly and the right winding drum assembly to the first variable frequency driver and the second variable frequency driver respectively, to synchronously control the double self-driven permanent magnet outer rotor elevator;

[0091] Step 3, the PLC synchronous controller sends the brake signal to the first variable frequency driver and the second variable frequency driver at the same time, and the PLC synchronous controller controls the meshing of the linkage sliding gear and the corresponding winding drum gear, and the non-fault winding drum assembly drives the fault winding drum assembly to rotate, to synchronously control the double self-driven permanent magnet outer rotor elevator.

[0092] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application and not to limit it, although the present application has been described in detail with reference to the above embodiments, those skilled in the art should understand that the specific embodiments of the present application can be modified or replaced by equivalents without departing from the spirit and scope of the present application, any modification or equivalent replacement thereof should be covered within the protection scope of the claims of the present application.

Claims

1. A synchronous control method of a dual self-driven permanent magnet outer rotor elevator, characterized by, Comprise: The double self-driven permanent magnet outer rotor hoist comprises an outer rotor permanent magnet drum assembly, a PLC synchronous controller and a fault-tolerant linkage device. The outer rotor permanent magnet drum assembly comprises a first outer rotor permanent magnet drum assembly and a second outer rotor permanent magnet drum assembly. The two outer rotor permanent magnet drum assemblies are structurally identical. Each outer rotor permanent magnet drum assembly comprises coaxially arranged left drum assembly and right drum assembly. The left drum assembly and the right drum assembly are symmetrically structured. The left drum assembly and the right drum assembly each comprise an encoder. The left drum assembly is equipped with a first variable frequency driver. The right drum assembly is equipped with a second variable frequency driver. The two variable frequency drivers are controlled by the PLC synchronous controller. When the left drum assembly and the right drum assembly are normal, there is no rigid connection between the left drum assembly and the right drum assembly. The PLC synchronous controller controls the synchronous rotation of the left drum assembly and the right drum assembly. When any one of the drum assemblies fails, the two drum assemblies are rigidly connected through the fault-tolerant linkage device. The PLC synchronous controller controls the rotation of the normal drum assembly, and the normal drum assembly drives the synchronous rotation of the failed drum assembly. The fault-tolerant linkage device comprises a pair of drum gears and a fault-tolerant linkage structure. The fault-tolerant linkage structure is installed on the rotating platform. One drum gear is installed on the main shaft of the left drum assembly and close to the right drum assembly. The other drum gear is installed on the main shaft of the right drum assembly and close to the left drum assembly. The fault-tolerant linkage structure comprises a pair of linkage sliding gears, a spline shaft, a pair of linkage yokes, a pair of linkage oil cylinders and a pair of support seats. The pair of support seats are installed on the rotating platform. Each support seat is installed with a linkage oil cylinder. The piston of each linkage oil cylinder is connected with a linkage yoke. Each linkage yoke is connected with a linkage sliding gear. The spline shaft is installed on the two support seats and can slide on the spline shaft. The pair of linkage sliding gears are installed on the spline shaft and can slide on the spline shaft. Step 1, detect whether the left drum assembly and the right drum assembly exist faults; if not, go to step 2, if yes, go to step 3; Step 2, the encoder of the left drum assembly collects the left drum position signal and speed signal in real time and transmits them to the PLC synchronous controller. The encoder of the right drum assembly collects the right drum position signal and speed signal in real time and transmits them to the PLC synchronous controller. The PLC synchronous controller obtains the synchronous control signal of the left drum assembly and the right drum assembly based on the master-slave control system. The PLC synchronous controller sends the synchronous control signal of the left drum assembly and the right drum assembly to the first variable frequency driver and the second variable frequency driver respectively to synchronously control the double self-driven permanent magnet outer rotor hoist. In step 2, the left drum assembly is the master motor and the right drum assembly is the slave motor. The first variable frequency driver drives the master motor to rotate, and the second variable frequency driver drives the slave motor to rotate, comprising: 1) obtain the first position deviation amount of the current position θ1 and the target position θ of the main motor ref of the main motor; 2) According to the first position deviation, the target speed of the main motor ω is obtained based on the position loop PI controller of the main motor ref ; 3) obtain the current rotating speed ω1 of the main motor and the target rotating speed ω ref of the first rotating speed deviation Δω1; 4) According to the first speed deviation Δω1, based on the field-oriented control / direct torque control controller of the master motor, to drive the master motor; 5), the current position θ1 of the main motor collected by the encoder of the main motor in real time as the first input quantity; the difference Δθ between the current position θ1 of the main motor collected by the encoder of the main motor in real time and the current position θ2 of the slave motor collected by the encoder of the slave motor as the second input quantity; the speed difference value obtained by the difference Δθ through the position loop PI controller of the slave motor as the third input quantity; 6) Optimizing the parameter k from the motor position loop PI controller based on neural network, according to the first input quantity, the second input quantity and the third input quantity p , k i ; 7) Based on the difference Δθ, the target speed ω of the slave motor is obtained from the optimized position loop PI controller of the slave motor ref′ ; 8), a second rotational speed deviation amount Δω2 is obtained from the current rotational speed ω2 of the motor and the target rotational speed ω ref′ of the motor 9), based on the second speed deviation Δω2, the field-oriented control / direct torque control controller of the slave motor is controlled to drive the slave motor; Step 3, the PLC synchronous controller sends a brake signal to the first variable frequency driver and the second variable frequency driver at the same time, and the PLC synchronous controller controls the engagement of the linkage sliding gear and the corresponding drum gear, and the non-fault drum assembly drives the fault drum assembly to rotate, so as to synchronously control the double self-driving permanent magnet outer rotor hoist.

2. The synchronous control method of the double self-driving permanent magnet outer rotor hoist according to claim 1, characterized in that, The neural network includes an input layer, a hidden layer and an output layer; the first input quantity, the second input quantity and the third input quantity are transmitted from the input layer to the hidden layer, and the neural network calculates the output quantity of each node in the output layer; based on the current output quantity of the neural network, the second speed deviation Δω2 is obtained; when the error between the second speed deviation Δω2 and the first speed deviation Δω1 does not exceed the limit value, the optimized position loop PI controller of the slave motor is determined according to the current output quantity of the neural network; when the error between the second speed deviation Δω2 and the first speed deviation Δω1 exceeds the limit value, the optimized position loop PI controller of the slave motor is determined by taking the optimal gradient value of the loss function as the target to adjust the parameters of the hidden layer and the input layer.

3. A double self-driven permanent magnet outer rotor elevator which hoists a shovel by using the control method according to claim 1 or 2, characterized by It comprises: The top pulley, the balance pulley, the lifting beam, the bucket, the lifting steel wire rope, the saddle, the bucket handle, the main rope, the A-shaped frame, the outer rotor permanent magnet drum assembly, the lifting arm, and the rotating platform are installed on the rotating platform. The top end of the A-shaped frame is connected to one end of the main rope, and the other end of the main rope is connected to the top pulley, so that the lifting arm is fixed by the main rope on the A-shaped frame. The end of the lifting arm away from the rotating platform is installed with the top pulley, and the left and right sides of the middle part of the lifting arm are respectively installed with one saddle. Each saddle is installed with one bucket handle, and the two bucket handles are connected to the bucket. The lifting steel wire rope is wound on the outer rotor permanent magnet drum assembly, and the lifting steel wire rope is connected to the lifting beam after passing through the top pulley and the balance pulley. The lifting beam is connected to the bucket. The outer rotor permanent magnet drum assembly rotates to wind or loosen the lifting steel wire rope, so as to lift or lower the bucket. The pushing motor pushes the two bucket handles to simultaneously insert or withdraw from the saddle.

4. The double self-driving permanent magnet outer rotor hoist according to claim 3, characterized in that, The left drum assembly comprises an outer rotor and an inner stator. The outer rotor comprises a web plate, a permanent magnet, a bearing and a left drum. The web plate is installed on the bearing, and the permanent magnet is installed on the side of the web plate facing the left drum. The inner stator comprises a main shaft support frame, a main shaft, a brake, a brake disc and a stator winding. The main shaft is installed on the main shaft support frame, and the main shaft is provided with the stator winding, the brake and the brake disc. The right winding drum assembly comprises an outer rotor and an inner stator, the outer rotor comprises a web plate, a permanent magnet, a bearing and a right winding drum, the web plate is installed on the bearing, the permanent magnet is installed on the side of the web plate facing the right winding drum, and the permanent magnet is attached to the inside of the right winding drum; the inner stator comprises a main shaft support frame, a main shaft, a brake, a brake disc and a stator winding, wherein the main shaft is installed on the main shaft support frame, and the stator winding, the brake and the brake disc are installed on the main shaft.

5. The double self-driven permanent magnet outer rotor hoist according to claim 4, wherein, The inclination direction of the rope groove on the left winding drum is opposite to the inclination direction of the rope groove on the right winding drum.

6. The double self-driven permanent magnet outer rotor hoist according to claim 5, wherein, The top pulley comprises a top left pulley and a top right pulley arranged coaxially and side by side, the center shafts of the top left pulley and the top right pulley are parallel to the center shafts of the left winding drum and the right winding drum and perpendicular to the center shaft of the balance pulley, the top left pulley is provided with a left rope groove and a right rope groove, the top right pulley is provided with a left rope groove and a right rope groove, and the balance pulley is provided with a front rope groove and a rear rope groove, wherein the rear rope groove is close to the permanent magnet winding drum assembly of the outer rotor; the lifting steel wire rope comprises a left lifting steel wire rope and a right lifting steel wire rope; The left lifting steel wire rope wound on the left winding drum passes through the left rope groove of the top left pulley, the front rope groove of the balance pulley and the left rope groove of the top right pulley in sequence and is then wound on the right winding drum; the right lifting steel wire rope wound on the left winding drum passes through the right rope groove of the top left pulley, the rear rope groove of the balance pulley and the right rope groove of the top right pulley in sequence and is then wound on the right winding drum; The balance pulley is used to control the same load of the left winding drum assembly and the right winding drum assembly.

7. The double self-driven permanent magnet outer rotor hoist according to claim 4, wherein, The first variable frequency driver is arranged in the first variable frequency driver cabinet, and the second variable frequency driver is arranged in the second variable frequency driver cabinet.

8. The double self-driven permanent magnet outer rotor hoist according to claim 3, wherein, During the movement of the lifting tool, when both winding drum assemblies are normal, the linkage oil cylinder controls the linkage shift gear to be located at the edge positions of the two ends of the spline shaft, and the linkage oil cylinder is locked, at this time, the linkage shift gear is not engaged with the winding drum gear, and the two winding drum assemblies are not rigidly connected. When the encoder of any drum assembly outputs a drum fault signal to the PLC synchronous controller during the movement of the sling, the PLC synchronous controller simultaneously outputs a brake signal to the first variable frequency driver and the second variable frequency driver; under the control of the first variable frequency driver and the second variable frequency driver, the brake and the brake disc of the left drum assembly and the right drum assembly cooperate to realize braking; the PLC synchronous controller simultaneously sends a start signal to the hydraulic control system of the two linkage oil cylinders, controls the piston to extend from the linkage oil cylinder, and drives the linkage yoke to move the linkage sliding gear, so that the linkage sliding gear is engaged with the corresponding drum gear, thereby realizing the rigid connection between the left drum assembly and the right drum assembly; when the PLC synchronous controller simultaneously outputs a start signal to the first variable frequency driver and the second variable frequency driver, the non-fault drum assembly drives the fault drum assembly to rotate synchronously.

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