An emergency braking control system for a box-type ship lift

Abstract

The present application provides an emergency braking control system for a box-type ship lift, which solves the technical problem of unstable emergency braking in the existing emergency braking control system for a box-type ship lift; it includes a main control system; it also includes four drive point braking systems distributed at the four corners of the ship lift, and the main control system is connected to one of the drive point braking systems; the four drive point braking systems are connected by CAN communication; the drive point braking system includes a controller, a hydraulic system, a speed encoder connected to a motor, and a CAN communication module, and the controller is respectively connected to the hydraulic system, the speed encoder, and the CAN communication module; the hydraulic system includes a hydraulic station, a hydraulic control oil circuit, and a disc brake mechanism for braking execution, and the hydraulic station is connected to the disc brake mechanism through the hydraulic control oil circuit. The present application is widely used in the technical field of lift braking control.

Description

Technical Field

[0001] The present application relates to a box-type ship lift, and more specifically, to an emergency braking control system for a box-type ship lift. Background Art

[0002] A box-type ship lift is a special facility that uses mechanical drive to carry ships in a ship chamber along a vertical direction for lifting and running, enabling ships to quickly pass through high dam water conservancy projects. Since the driving force (torque) required for the ship chamber and the corresponding transmission machinery are relatively large, in order to solve the difficulties of equipment layout and manufacturing, the ship chamber drive mechanism generally adopts a mechanical transmission scheme of multi-unit and multi-motor decentralized drive and mechanical shaft rigid connection. Through multi-axis and multi-motor mechanical shaft synchronous drive, the torque balance between multiple drive points and the synchronous follow-up of the running speed and position are ensured, so as to realize the safe lifting and running of the ship chamber in a horizontal state throughout the whole stroke. The ship chamber body of the box-type ship lift is huge, and its operation is driven in a decentralized manner by 4 drive points and 4 sets of transmission devices arranged at the four corners of the ship chamber. Each drive point is driven by an AC variable frequency motor after deceleration, and through a short shaft rigid connection, a pinion is rotated from one side to make the ship chamber lift and run along the rack vertically laid on the concrete tower column wall. The 4 drive mechanisms are connected by a rectangular rigid synchronous shaft to form a "mechanical synchronization" drive system.

[0003] However, in actual use, the box-type ship lift equipment is 200 meters long, has a large weight, and a fast normal running speed. When an emergency brake occurs, it is required to stop within 5 seconds, and there will be a large torque deviation among the 4 drive points, making it difficult to meet the requirement of smooth operation. Summary of the Invention

[0004] In order to solve the problem of unstable emergency braking of the existing emergency braking control system and method for a box-type ship lift, the technical solution adopted in the present application is: to provide an emergency braking control system for a box-type ship lift with stable emergency braking, including a main control system; it also includes four drive point braking systems distributed at the four corners of the ship lift, and the main control system is connected to one of the drive point braking systems; the four drive point braking systems are connected by CAN communication; the drive point braking system includes a controller, a hydraulic system, a speed encoder connected to the motor, and a CAN communication module, and the controller is respectively connected to the hydraulic system, the speed encoder, and the CAN communication module; the hydraulic system includes a hydraulic station, a hydraulic control oil circuit, and a disc brake mechanism for braking execution, and the hydraulic station is connected to the disc brake mechanism through the hydraulic control oil circuit.

[0005] Preferably, the hydraulic control oil circuit includes:

[0006] A first working pipeline connecting the hydraulic station and the brake cylinder of the disc brake mechanism, and a first solenoid valve is provided on the first working pipeline;

[0007] A second working pipeline connecting the brake oil cylinder and the oil tank of the disc brake mechanism, wherein a second solenoid valve and a proportional valve are connected in series on the second working pipeline;

[0008] A third working pipeline is connected with the brake oil cylinder and the oil tank of the disc brake mechanism. A third electromagnetic valve and a regulating valve are provided in series on the third working pipeline.

[0009] Preferably, the hydraulic control oil circuit also includes a fourth working pipeline, one end of which is connected to the output end of the hydraulic station and the other end is connected to the input end of the regulating valve; the fourth working pipeline is provided with a fourth solenoid valve and a speed regulating valve connected in series.

[0010] Preferably, the regulating valve includes a first overflow valve and an adjustable flow valve connected in parallel.

[0011] Preferably, the hydraulic control oil circuit further includes a pressure relief oil circuit, one end of which is connected to the output end of the hydraulic station and the other end is connected to the oil tank; a second overflow valve is provided on the pressure relief oil circuit.

[0012] Preferably, the output end of the hydraulic station is also connected to an accumulator, and a plurality of pressure sensors are distributed on the hydraulic control oil circuit.

[0013] The present invention also provides a control method for an emergency brake control system of a box-type ship lift, comprising the following steps:

[0014] (1) According to the theoretical calculation of the hydraulic system pressure p0 at the beginning of emergency braking, the hydraulic system t (n+1) Theoretical pressure at time p (n+1) ;

[0015] (2) The theoretical pressure p (n+1) With the set minimum threshold p L1 , maximum threshold p H1 Compare, if it is within the threshold range, the controller assigns p to the proportional valve (n+1) , it indicates normal, and the pressure in the hydraulic system is roughly adjusted; if it is outside the threshold range, it indicates abnormality, and the controller assigns p0 to the proportional valve, and the hydraulic system is depressurized;

[0016] (3) The real-time pressure value p of the hydraulic system pt With t (n+1) Theoretical pressure at time p (n+1) The difference is calculated and compared with the set threshold. Based on the comparison result, the controller assigns a value to the proportional valve to further adjust the pressure in the hydraulic system.

[0017] (4) Repeat step (3) until the emergency braking is completed.

[0018] Preferably, the formula of step (1) is:

[0019]

[0020] in:

[0021] M b0 : The initial torque value of the driving system at a single braking point just after braking;

[0022] N: The maximum pressure that a single disc brake mechanism can exert on the brake disc;

[0023] p (n+1) :t (n+1) The hydraulic system pressure that actuates the brake system at all times;

[0024] p (n) :t (n) The hydraulic system pressure of the brake system at the moment of actuation;

[0025] I: Equivalent moment of inertia of the four driving point braking systems converted to the motor shaft;

[0026] Δε (n) :t (n) The motor shaft angular acceleration adjustment at each moment;

[0027] n: number of brake cylinders in a single disc brake mechanism;

[0028] μ: friction coefficient between the brake shoe and the brake disc of the disc brake mechanism;

[0029] R b : Braking radius of disc brake mechanism;

[0030] S: The area of the rod cavity of the brake cylinder of the disc brake mechanism;

[0031] δ (n) :t (n) The deviation between the theoretical angular velocity and the actual angular velocity of the motor shaft at this moment.

[0032] Preferably, step (2) specifically includes:

[0033] a. When p L1 ≤p (n+1) ≤p H1 , then the second solenoid valve, the third solenoid valve, and the fourth solenoid valve are energized, and the first solenoid valve is not energized. The second and fourth solenoid valves are turned on, and the third and first solenoid valves are turned off. The proportional valve is assigned a value of p (n+1) , accumulator and proportional valve brake pressure relief;

[0034] b. When p (n+1) <p L1 or p (n+1) >p H1, then the first solenoid valve, the second solenoid valve, the third solenoid valve, and the fourth solenoid valve are all de-energized, the third solenoid valve is conducting, the first solenoid valve, the second solenoid valve, and the fourth solenoid valve are cut off, the proportional valve is assigned p0, and the first relief valve and the adjustable throttle valve are depressurized.

[0035] 10. The control method of the emergency braking control system of the box-type ship lift as claimed in claim 8, characterized in that: step (3) specifically includes:

[0036] a. When |p pt -p (n+1) | ≤ 10, the system braking is within the normal control range, the second solenoid valve is energized, the first solenoid valve, the third solenoid valve, and the fourth solenoid valve are de-energized, the second solenoid valve and the third solenoid valve are conducting, the first solenoid valve and the fourth solenoid valve are cut off, normal depressurization is performed, and the proportional valve PR is not required to participate in the regulation;

[0037] b. When 10 < p pt -p (n+1) < 15, then the second solenoid valve is energized, the first solenoid valve, the third solenoid valve, and the fourth solenoid valve are de-energized, the second solenoid valve and the third solenoid valve are conducting, the first solenoid valve and the fourth solenoid valve are cut off, the proportional valve is assigned p (n+1) , and the proportional valve, the first relief valve, and the adjustable throttle valve are depressurized;

[0038] c. When p pt -p (n+1) < -10, then the first solenoid valve, the second solenoid valve, the third solenoid valve, and the fourth solenoid valve are energized, the third solenoid valve is cut off, the first solenoid valve, the second solenoid valve, and the fourth solenoid valve are conducting, the proportional valve is assigned p (n+1) , and the accumulator and the proportional valve are braked;

[0039] d. When p pt -p (n+1) ≥ 15, then the second solenoid valve is energized, the first solenoid valve, the third solenoid valve, and the fourth solenoid valve are all de-energized, the second solenoid valve and the third solenoid valve are conducting, the first solenoid valve and the fourth solenoid valve are cut off, the proportional valve is assigned p (n+1) , and the proportional valve, the first relief valve, and the adjustable throttle valve are depressurized.

[0040] The beneficial effects of the present invention are as follows: there is a main control system and four driving point braking systems distributed at the four corners of the ship lift. Each driving point braking system includes a controller, a hydraulic system, a speed encoder connected to the motor, and a CAN communication module. The hydraulic system includes a hydraulic station, a hydraulic control oil circuit, and a disc brake mechanism for braking execution. The hydraulic station is connected to the disc brake mechanism through the hydraulic control oil circuit. The controller is connected to various solenoid valves and other components on the hydraulic control oil circuit to control the conduction, cut-off, or opening degree of each component, thereby controlling the pipeline switching, adjusting the hydraulic system pressure of each driving point braking system to make it close to the theoretical pressure value, and thus controlling the speed of each driving point braking system, reducing the torque difference of the 4 driving points. The whole process is adjusted in real time, so as to achieve the effect of smooth emergency braking of the lift. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings required for use in the embodiments or the description of the prior art. Obviously, the following drawings are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0042] Figure 1 is the connection block diagram of the emergency braking control system of the present invention;

[0043] Figure 2 is the connection block diagram of the first driving point braking system;

[0044] Figure 3 is the schematic diagram of the hydraulic system.

[0045] Symbol description in the figure:

[0046] 1. Main control system; 2. First driving point braking system; 3. Second driving point braking system; 4. Third driving point braking system; 5. Fourth driving point braking system; 6. Controller; 7. Hydraulic system; 8. Speed sensor; 9. Speed encoder; 10. CAN communication module; 11. Hydraulic station; 12. Brake cylinder;

[0047] S1. First solenoid valve; S2. Second solenoid valve; S3. Third solenoid valve; S4. Fourth solenoid valve; PR. Proportional valve; RV1. First overflow valve; FA. Adjustable throttle valve; FCV. Speed control valve; RV2 Second overflow valve; A. Accumulator. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0048] In order to make the technical problems, technical solutions and beneficial effects to be solved by this application more clearly understood, the following further details this application in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain this application and are not used to limit this application.

[0049] It should be noted that the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of this application, "a plurality of" means two or more unless otherwise specifically defined.

[0050] Now, the box-type ship lift emergency braking control system and method provided by the embodiments of this application will be described. Please refer to Figure 1 、 Figure 2 , which is a principle block diagram of the box-type ship lift emergency braking control system and method. The box-type ship lift emergency braking control system and method include a main control system 1 and four drive point braking systems distributed at the four corners of the ship lift. The main control system 1 is connected to one of the drive point braking systems; the four drive point braking systems are connected by CAN communication. In this embodiment, the four drive point braking systems are respectively a first drive point braking system 2, a second drive point braking system 3, a third drive point braking system 4 and a fourth drive point braking system 5, and are connected to each other by CAN communication; the main control system 1 is connected to the first drive point braking system 2.

[0051] Furthermore, in one of the embodiments, each drive point braking system includes a controller 6, a hydraulic system 7, a speed encoder 9 connected to the motor, and a CAN communication module 10. The controller 6 is respectively connected to the hydraulic system 7, the speed encoder 9 and the CAN communication module 10. The hydraulic system 7 is controlled by the controller 6, and its output end is connected to the motor for braking execution to achieve smooth operation during emergency braking. The speed encoder 9 is connected to the motor shaft for collecting the speed signal of the motor and transmitting the signal to the controller 6. The CAN communication module 10 is used to complete the mutual communication between the drive point braking systems and can receive the remote control of the main control system 1 through it. Preferably, a speed sensor 8 can be set on the ship lift cabin for collecting the ship lift speed.

[0052] Please refer to Figure 3, the hydraulic system 7 includes a hydraulic station 11, a hydraulic control oil circuit, and a disc brake mechanism for braking execution (including a brake cylinder 12). The hydraulic station 11 is connected to the disc brake mechanism through the hydraulic control oil circuit to control the disc brake mechanism to achieve braking execution. Further, the disc brake mechanism acts on the motor output shaft to increase the system friction and eliminate the power to achieve the purpose of braking. The cooperation between the disc brake mechanism and the motor belongs to the prior art. The focus of this application is on how to smoothly deliver hydraulic oil during emergency braking so that the lift runs smoothly; therefore, the connection and action relationship between the disc brake mechanism and the motor will not be further elaborated.

[0053] The hydraulic control oil circuit further includes a first working pipeline connecting the hydraulic station 11 and the brake cylinder 12 of the disc brake mechanism. A first solenoid valve S1 for controlling conduction is provided on the first working pipeline.

[0054] The hydraulic control oil circuit further includes a second working pipeline connecting the brake cylinder 12 of the disc brake mechanism and the oil tank. A second solenoid valve S2 and a proportional valve PR are connected in series on the second working pipeline. The second solenoid valve S2 is used to control the conduction of the second working pipeline. The proportional valve PR receives the command signal from the controller 6 and performs proportional adjustment as required to control the output volume of the hydraulic oil.

[0055] The hydraulic control oil circuit further includes a third working pipeline connecting the brake cylinder 12 of the disc brake mechanism and the oil tank. A third solenoid valve S3 and a regulating valve are connected in series on the third working pipeline. The regulating valve includes a first relief valve RV1 and an adjustable throttle valve FA connected in parallel. The third solenoid valve S3 is used to control the conduction of the third working pipeline. The first relief valve RV1 is used to limit the maximum pressure of this pipeline. When the pressure exceeds the set value, the hydraulic oil is led to the oil tank. The adjustable throttle valve FA and the first relief valve RV1 are used to adjust the flow rate and pressure of the hydraulic oil and can be adjusted manually.

[0056] The hydraulic control oil circuit further includes a fourth working pipeline. One end of the fourth working pipeline is connected to the output end of the hydraulic station 11, and the other end of the fourth working pipeline is connected to the input end of the regulating valve. A fourth solenoid valve S4 and a speed control valve FCV are connected in series thereon. The fourth regulating valve is used to control conduction, and the speed control valve FCV is used to adjust the flow rate of the hydraulic oil to control the speed stability.

[0057] The hydraulic control oil circuit further includes a pressure relief oil circuit. One end of the pressure relief oil circuit is connected to the output end of the hydraulic station 11, and the other end of the pressure relief oil circuit is connected to the oil tank. A second relief valve RV2 is provided thereon to limit the maximum pressure of this pipeline. When the pressure exceeds the set value, the hydraulic oil is led to the oil tank.

[0058] In one embodiment, the hydraulic station 11 is further connected to an accumulator A, which is used to store and release hydraulic oil. When the system pressure is higher than the pressure inside the accumulator A, the accumulator A stores oil; when the system pressure is lower than the pressure inside the accumulator A, the accumulator A discharges oil. A first pressure sensor PT1 is provided at the output end of the hydraulic station 11 to detect the pressure of the accumulator A. A second pressure sensor PT2 is also provided on the pipeline near the disc brake mechanism to detect the pressure of the disc brake mechanism. The first pressure sensor PT1 and the second pressure sensor PT2 provide the pressures at various points of the hydraulic system 7 to ensure the stability of the system braking. Of course, the number of pressure sensors is not limited, and a third pressure sensor PT3 can also be set, and the average value of all detected values is taken as the system pressure.

[0059] Further, each valve element on the pipeline is connected to the controller 6 and is controlled by the instructions of the controller 6.

[0060] During an emergency brake, the controller 6 of each drive point braking system assigns a value to the proportional valve PR according to the relationship between pressure and speed, and then controls the on-off of each solenoid valve to control the pressure in the hydraulic system 7, so that the pressure of the hydraulic system 7 approaches the theoretical pressure value, thereby making the speed of each drive point braking system approach the theoretical speed, achieving a small torque difference among the 4 drive points. The whole process is adjusted in real time, so as to achieve the effect of smooth emergency braking of the elevator. Next, this process will be further described:

[0061] When receiving an emergency brake signal, the controller 6 presets the speed curve required for successful emergency braking, and inputs it together with the speed value of the real-time acquisition speed encoder 9 into the PID control module to calculate the theoretical required pressure P0 of the hydraulic system 7, and compares it with the average pressure P1 of the hydraulic system 7. The difference between the two is compared with two thresholds set by experience:

[0062] (1) If P1 - P0 ≥ 15, the second solenoid valve S2 is energized and conducts, the third solenoid valve S3 is not energized and does not conduct, the proportional valve PR is assigned the value P0, and the proportional valve PR, the first relief valve RV1 and the adjustable throttle valve FA are used for pressure relief to accelerate the pressure drop of the hydraulic system 7;

[0063] (2) If 10 < P1 - P0 < 15, the second solenoid valve S2 is energized, the first solenoid valve S1, the third solenoid valve S3 and the fourth solenoid valve S4 are not energized, the second solenoid valve S2 and the third solenoid valve S3 conduct, the first solenoid valve S1 and the fourth solenoid valve S4 are cut off, the proportional valve PR is assigned the value P0, and the proportional valve PR, the first relief valve RV1 and the adjustable throttle valve FA are used for pressure relief;

[0064] (3) If -10 ≤ P1 - P0 ≤ 10, the second solenoid valve S2, the third solenoid valve S3, and the fourth solenoid valve S4 are energized. The second solenoid valve S2 and the fourth solenoid valve S4 are turned on, the third solenoid valve S3 is turned off, and the PR value of the proportional valve is dynamically adjusted;

[0065] (4) If P1 - P0 ≤ -10, the second solenoid valve S2, the third solenoid valve S3, and the fourth solenoid valve S4 are energized, and the first solenoid valve S1 is energized for 100 ms. The first solenoid valve S1, the second solenoid valve S2, and the fourth solenoid valve S4 are turned on, the third solenoid valve S3 is turned off, the proportional valve PR is assigned the value P0, and the accumulator A discharges oil.

[0066] (5) Repeat the above comparison and assignment until the speed of the speed encoder 9 is 0. The second solenoid valve S2, the third solenoid valve S3, and the fourth solenoid valve S4 are energized, the first solenoid valve S1 is not energized, the second solenoid valve S2 and the fourth solenoid valve S4 are turned on, the first solenoid valve S1 and the third solenoid valve S3 are turned off, the proportional valve PR is assigned the value 0, and the oil in the system is returned to the fuel tank.

[0067] The following is a detailed description again in combination with specific embodiments:

[0068] First, with a standard water depth of 3 m and considering factors such as system friction resistance, calculate the pressure p0 of the hydraulic system 7 at the start of emergency braking:

[0069] According to: M b0 ×4 = M z + I·ε g

[0070]

[0071] I = J red = 106 kg·m 2

[0072]

[0073] Obtain: M b0 7]]= 963 Nm

[0074] According to:

[0075] Obtain:

[0076] In the formula:

[0077] M b0 : The initial torque value of the single drive point braking system just at the start of braking;

[0078] M z : The torque corresponding to the friction resistance of the drive point braking system and the stiffness resistance of the wire rope;

[0079] I = J red : The equivalent moment of inertia of the four - drive - point braking system converted to the motor shaft. As can be seen from the research reports of three motors: 106 kg·m 2 ;

[0080] ε g : Deceleration 0.04 m·s -2 The corresponding angular deceleration;

[0081] F z : The braking frictional resistance at the drive point and the resistance of the wire rope, taking 800 kN;

[0082] D p : Pitch - diameter of the pinion of the speed reducer, 0.764 m;

[0083] i p : Transmission ratio from the motor shaft to the pinion shaft of the speed reducer, 200;

[0084] M r : Frictional moment between the short screw of the disc brake mechanism and the end face of the thrust bearing, 2.6 kN·m;

[0085] i r : Transmission ratio from the motor shaft to the short screw of the disc brake mechanism, n m ÷n r = 1000÷40 = 25;

[0086] ω m : Angular velocity corresponding to 1000 rpm of the motor shaft, 104.7 s -1 ;

[0087] t: Time taken for the drive - point braking system to decelerate at 0.04 m·s -1 from 0.2 m·s -2 is 5 s;

[0088] p0: Initial value of the hydraulic pipeline pressure when the disc brake mechanism just brakes;

[0089] N: Maximum pressure that a single disc brake mechanism can exert on the brake disc, 13625 N;

[0090] η: Efficiency value of the pressure loss along the hydraulic pipeline, temporarily taking 1 here;

[0091] S: Area of the rod - end chamber of the brake cylinder of the disc brake mechanism, calculated to be 1708 mm 2 ;

[0092] n: Number of brake cylinders of a single - set disc brake mechanism, 4;

[0093] μ: Friction coefficient between the brake shoe and the brake disc of the disc brake mechanism, 0.4;

[0094] R b : Braking radius of the disc brake mechanism, 0.25 - 0.045 = 0.205 m.

[0095] Secondly, calculate the pressure p of the hydraulic system 7 at the moment t (n+1) and its relationship with speed: (n+1)

[0096] t (n) moment, theoretical angular velocity of the motor shaft:

[0097] t (n) moment, actual angular velocity of the motor shaft: ω m(n) = ω e(n) ·i e

[0098] t (n) moment, deviation between the theoretical and actual angular velocities of the motor shaft:

[0099]

[0100] In the formula:

[0101] ω' m(n) : Theoretical angular velocity of the motor shaft at moment t (n) ;

[0102] ω e0 : Initial angular velocity of the measurement shaft of the speed encoder at the start of braking;

[0103] i e : Transmission ratio from the motor shaft to the measurement shaft of the speed encoder;

[0104] ω m(n) : Actual angular velocity of the motor shaft at moment t (n) ;

[0105] ω e(n) : t (n) moment, actual angular velocity of the measurement shaft of the speed encoder;

[0106] δ (n) : t (n) moment, deviation between the theoretical and actual angular velocities of the motor shaft.

[0107] t (n) moment, take the angular acceleration adjustment amount:

[0108] According to: ΔM b(n) ×4 = -IΔε (n) ; p (n+1) = p (n)+Δp (n)

[0109] wherein:

[0110] ΔM b(n) : t (n) the torque increment that the driving point braking system should apply at time t;

[0111] Δp (n) : t (n) the hydraulic system pressure increment of the driving point braking system at time t;

[0112] p (n) : t (n) the hydraulic system pressure of the driving point braking system at time t;

[0113] p (n+1) : t (n+1) the hydraulic system pressure of the driving point braking system at time t.

[0114] It is obtained that:

[0115] Finally, during an emergency brake, the controller 6 of each driving point braking system assigns a value to the proportional valve PR according to the relationship between pressure and speed, so as to adjust the states of the 4 driving points in real time, reduce the torque difference of the 4 driving points, and achieve smooth operation of the lift. First, compare with the set minimum threshold p L1 and the maximum threshold p H1 (here, according to experience, the minimum threshold p L1 is taken as 40, and the maximum threshold p H1 is taken as 80) for rough adjustment:

[0116] (1) When 40 ≤ p (n+1) ≤ 80, the second solenoid valve S2, the third solenoid valve S3, and the fourth solenoid valve S4 are energized, the first solenoid valve S1 is not energized, the second solenoid valve S2 and the fourth solenoid valve S4 are conducting, the third solenoid valve S3 and the first solenoid valve S1 are cut off, the proportional valve PR is assigned a value of p (n+1) , and the accumulator A and the proportional valve PR brake and relieve pressure;

[0117] (2) When p (n+1) < 40 or p (n+1) > 80, the first solenoid valve S1, the second solenoid valve S2, the third solenoid valve S3, and the fourth solenoid valve S4 are all not energized, the third solenoid valve S3 is conducting, the other solenoid valves are cut off, the proportional valve PR is assigned a value of p0, and the first relief valve RV1 and the adjustable throttle valve FA relieve pressure;

[0118] Then, take the measured average value of the hydraulic control oil circuit pressure: That is, the average pressure is equal to the average value of the pressures detected by the pressure sensors at various locations within the system. There are two pressure sensors within the system. This average value is subtracted from the theoretical hydraulic system pressure p at time t (n+1) at time t (n+1) and compared with an empirically set threshold value for fine adjustment:

[0119] (1) When |p pt - p (n+1) | ≤ 10, the system brake is within the normal control range. The second solenoid valve S2 is energized, and the first solenoid valve S1, the third solenoid valve S3, and the fourth solenoid valve S4 are not energized. The second solenoid valve S2 and the third solenoid valve S3 are conducting, and the first solenoid valve S1 and the fourth solenoid valve S4 are cut off. Normal pressure relief is carried out, and the proportional valve PR is not required to participate in the regulation;

[0120] (2) When 10 < p pt - p (n+1) < 15, the second solenoid valve S2 is energized, and the first solenoid valve S1, the third solenoid valve S3, and the fourth solenoid valve S4 are not energized. The second solenoid valve S2 and the third solenoid valve S3 are conducting, and the first solenoid valve S1 and the fourth solenoid valve S4 are cut off. The proportional valve PR is assigned p (n+1) , and the proportional valve PR, the first relief valve RV1, and the adjustable throttle valve FA relieve pressure;

[0121] (3) When p pt - p (n+1) < -10, the first solenoid valve S1 (energized only for 100 ms), the second solenoid valve S2, the third solenoid valve S3, and the fourth solenoid valve S4 are energized. The third solenoid valve S3 is cut off, and the other solenoid valves are conducting. The proportional valve PR is assigned p (n+1) , and the accumulator A and the proportional valve PR are braked; [[ID=�1]]

[0122] (4) When p pt - p (n+1) ≥ 15, the second solenoid valve S2 is energized, and the first solenoid valve S1, the third solenoid valve S3, and the fourth solenoid valve S4 are all not energized. The second solenoid valve S2 and the third solenoid valve S3 are conducting, and the other solenoid valves are cut off. The proportional valve PR is assigned p (n+1) , and the proportional valve PR, the first relief valve RV1, and the adjustable throttle valve FA relieve pressure.

[0123] Preferably, to ensure system stability, two of each solenoid valve can be arranged in parallel, that is, two of each of the first solenoid valve S1, the second solenoid valve S2, the third solenoid valve S3, and the fourth solenoid valve S4 are provided.

[0124] The present invention is provided with a main control system 1 and four drive point braking systems distributed at the four corners of the ship lift. Each drive point braking system includes a controller 6, a hydraulic system 7, a speed encoder 9 connected to the motor, and a CAN communication module 10. The hydraulic system 7 includes a hydraulic station 11, a hydraulic control oil circuit, and a disc brake mechanism for braking execution. The hydraulic station 11 is connected to the brake cylinder 12 of the disc brake mechanism through the hydraulic control oil circuit. The controller 6 is connected to various solenoid valves and other components on the hydraulic control oil circuit to control the conduction, cut-off, or opening degree of each component, thereby controlling the pipeline switching, adjusting the pressure of the hydraulic system 7 of each drive point braking system to make it close to the theoretical pressure value, thereby controlling the speed of each drive point braking system, reducing the torque difference of the 4 drive points. The whole process is adjusted in real time, so as to achieve the effect of smooth emergency braking of the lift.

[0125] The above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it; although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application, and should all be included in the protection scope of the present application.

Claims

1. An emergency braking control system for a box-type ship lift, comprising a main control system; characterized in that: It also includes four driving point braking systems distributed at the four corners of the ship lift, and the main control system is connected to one of the driving point braking systems; the four driving point braking systems are connected by CAN communication; the driving point braking system includes a controller, a hydraulic system, a speed encoder connected to the motor, and a CAN communication module, and the controller is respectively connected to the hydraulic system, the speed encoder and the CAN communication module; the hydraulic system includes a hydraulic station, a hydraulic control oil circuit, and a disc brake mechanism for braking execution, and the hydraulic station is connected to the disc brake mechanism through the hydraulic control oil circuit; The control method of the emergency braking control system of the box-type ship lift includes the following steps: (1)Hydraulic system pressure at the start of emergency braking calculated according to theory and the theoretical pressure at the moment as the hydraulic system is obtained during emergency braking ; (2) Compare the theoretical pressure with the set minimum threshold , maximum threshold . If it is within the threshold range, the controller assigns a value to the proportional valve , indicating normal, and roughly adjusts the pressure in the hydraulic system; if it is outside the threshold range, it indicates abnormal, and the controller assigns a value to the proportional valve , and the hydraulic system relieves pressure; (3) Subtract the real-time pressure value of the hydraulic system from the theoretical pressure at a certain moment, compare the result with a set threshold value, and according to the comparison result, the controller assigns a value to the proportional valve to further adjust the pressure in the hydraulic system; (4) Repeat step (3) until the emergency braking ends; The formula of step (1) is: Where: : Initial torque value when the single braking point drive system just starts braking; : The maximum pressure that a single disc brake mechanism can exert on the brake disc; :[[]]END The hydraulic system pressure of the moment-driven braking system; : Hydraulic system pressure of the moment drive point braking system; : The equivalent moment of inertia of the four-drive-point braking system reduced to the motor shaft; : Adjustment amount of angular acceleration of the motor shaft at a moment; : Number of brake cylinders of a single set of disc brake mechanism; : Coefficient of friction between the brake shoe and the brake disc of the disc brake mechanism; : Braking radius of disc brake mechanism; : The area of the rod chamber of the brake cylinder of the disc brake mechanism; :[[]]END Deviation between the theoretical angular velocity and the actual angular velocity of the motor shaft at a moment.

2. The emergency braking control system of the box-type ship lift according to claim 1, wherein: The hydraulic control oil circuit includes: The first working pipeline connecting the hydraulic station and the brake cylinder of the disc brake mechanism, and a first solenoid valve is arranged on the first working pipeline; The second working pipeline connecting the brake cylinder of the disc brake mechanism and the fuel tank, and a second solenoid valve and a proportional valve are arranged in series on the second working pipeline; The third working pipeline connecting the brake cylinder of the disc brake mechanism and the fuel tank, and a third solenoid valve and a regulating valve are arranged in series on the third working pipeline.

3. The emergency braking control system of the box-type ship lift according to claim 2, characterized in that: The hydraulic control oil circuit further includes a fourth working pipeline, one end of which is communicated with the output end of the hydraulic station, and the other end is communicated with the input end of the regulating valve; a fourth solenoid valve and a speed regulating valve are arranged in series on the fourth working pipeline.

4. The emergency braking control system for the box-type ship lift as claimed in claim 3, wherein: The regulating valve includes a first overflow valve and an adjustable throttle valve connected in parallel.

5. The emergency braking control system of the box-type ship lift as described in claim 4, characterized in that: The hydraulic control oil circuit further includes a pressure relief oil circuit, one end of which is communicated with the output end of the hydraulic station, and the other end is communicated with the fuel tank; a second overflow valve is arranged on the pressure relief oil circuit.

6. The emergency braking control system of the box-type ship lift according to claim 4 or 5, characterized in that: An accumulator is further communicated with the output end of the hydraulic station, and a plurality of pressure sensors are distributed on the hydraulic control oil circuit.

7. The emergency braking control system of the box-type ship lift according to claim 6, characterized in that: Step (2) specifically includes: a. When , the second solenoid valve, the third solenoid valve, and the fourth solenoid valve are energized, the first solenoid valve is not energized, the second solenoid valve and the fourth solenoid valve are conducting, the third solenoid valve and the first solenoid valve are cut off, the proportional valve is assigned a value of , and the accumulator and the proportional valve brake and relieve pressure; b. When or , then none of the first solenoid valve, the second solenoid valve, the third solenoid valve, and the fourth solenoid valve is energized. The third solenoid valve is conducting, and the first solenoid valve, the second solenoid valve, and the fourth solenoid valve are cut off. The proportional valve is assigned a value of , and the first relief valve and the adjustable throttle valve are depressurized.

8. The emergency braking control system of the box-type ship lift as claimed in claim 6, wherein: Step (3) specifically includes: a. When , the system brake is within the normal control range, the second solenoid valve is energized, and the first, third, and fourth solenoid valves are not energized. The second and third solenoid valves are conducting, and the first and fourth solenoid valves are cut off. Normal pressure relief is performed, and the proportional valve PR is not required to participate in the regulation; b. When , the second solenoid valve is energized, and the first, third, and fourth solenoid valves are not energized. The second and third solenoid valves are conducting, and the first and fourth solenoid valves are cut off. The proportional valve is assigned , and the proportional valve, the first relief valve, and the adjustable throttle valve are depressurized; c. When , the first solenoid valve, the second solenoid valve, the third solenoid valve, and the fourth solenoid valve are energized, the third solenoid valve is cut off, the first solenoid valve, the second solenoid valve, and the fourth solenoid valve are turned on, and the proportional valve is assigned a value of , and the accumulator and the proportional valve are braked; d. When , the second solenoid valve is energized, and the first, third, and fourth solenoid valves are all de-energized. The second and third solenoid valves are conducting, and the first and fourth solenoid valves are cut off. The proportional valve is assigned , and the proportional valve, the first relief valve, and the adjustable throttle valve are depressurized.

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