An engineering machinery braking recovery control method, device and system

Abstract

The present application discloses a control method, device and system for braking energy recovery of construction machinery. The control method for braking energy recovery of construction machinery includes: switching the braking mode according to the depression depth of the brake pedal; wherein, the braking mode includes an electric motor braking mode and a hybrid braking mode; the hybrid braking mode includes electric motor braking and mechanical braking, and the electric motor braking mode includes electric motor braking; and performing braking energy recovery according to the braking mode. The present application can solve the problem of excessive loss caused by relying solely on mechanical braking.

Description

Technical Field

[0001] The present application relates to the technical field of construction machinery, and particularly relates to a braking recovery control method, device and system for construction machinery. Background Art

[0002] In construction machinery, an electric reach stacker will travel at high speed due to inertia during operation under the conditions of no braking and no throttle, which is not conducive to operation and has low safety. Moreover, the braking of an electric reach stacker usually adopts mechanical brake braking, resulting in large energy loss and large wear, which easily affects the braking performance and braking life. Summary of the Invention

[0003] To solve the above technical problems, the present application is proposed. Embodiments of the present application provide a braking recovery control method, device and system for construction machinery, which can solve the problem of excessive loss caused by relying solely on mechanical brake braking.

[0004] According to one aspect of the present application, there is provided a braking recovery control method for construction machinery, including: switching a braking mode according to the depression depth of a brake pedal; wherein, the braking mode includes an electric motor braking mode and a hybrid braking mode; the hybrid braking mode includes electric motor braking and mechanical braking, and the electric motor braking mode includes electric motor braking; performing braking energy recovery according to the braking mode.

[0005] In one embodiment, the switching the braking mode according to the depression depth of the brake pedal includes: when the depression depth of the brake pedal is greater than a first preset angle, switching to the hybrid braking mode; or when the depression depth of the brake pedal is less than or equal to the first preset angle, switching to the electric motor braking mode.

[0006] In one embodiment, the performing braking energy recovery according to the braking mode includes: adjusting the braking torque of an electric motor according to the braking mode and vehicle operating parameters; performing the braking energy recovery according to the braking torque.

[0007] In one embodiment, the vehicle operating parameters include the current vehicle speed, and the adjusting the braking torque of the electric motor according to the braking mode and vehicle operating parameters includes: in a braking state, when the current vehicle speed is greater than a first preset vehicle speed, adjusting the braking torque of the electric motor according to the vehicle operating parameters.

[0008] In one embodiment, the vehicle operating parameters include weighing information, and the weighing information includes the current load of the construction machinery and the limit load of the construction machinery. When in the braking state and the current vehicle speed is greater than a first preset vehicle speed, adjusting the braking torque of the motor according to the vehicle operating parameters includes: when in the braking state and the current vehicle speed is greater than the first preset vehicle speed and less than or equal to a second preset vehicle speed, adjusting the braking torque of the motor according to the weighing information and the current vehicle speed; the braking torque of the motor is positively correlated with the current load, the braking torque of the motor is negatively correlated with the limit load, and the braking torque of the motor is positively correlated with the current vehicle speed; wherein, the second preset vehicle speed is greater than the first preset vehicle speed.

[0009] In one embodiment, the vehicle operating parameters include weighing information, and the weighing information includes the current load of the construction machinery and the limit load of the construction machinery. When in the braking state and the current vehicle speed is greater than a first preset vehicle speed, adjusting the braking torque of the motor according to the vehicle operating parameters further includes: when in the braking state and the current vehicle speed is greater than the second preset vehicle speed, adjusting the braking torque of the motor according to the weighing information; wherein, the second preset vehicle speed is greater than the first preset vehicle speed, the braking torque of the motor is positively correlated with the current load, and the braking torque of the motor is negatively correlated with the limit load.

[0010] In one embodiment, the vehicle operating parameters include the current vehicle speed. Adjusting the braking torque of the motor according to the braking mode and the vehicle operating parameters further includes: when in the braking state and the current vehicle speed is less than or equal to the first preset vehicle speed, not performing the braking energy recovery.

[0011] In one embodiment, before switching the braking mode according to the depression depth of the brake pedal, the above-mentioned construction machinery braking recovery control method further includes: braking according to the depression depth of the brake pedal and the opening degree of the accelerator pedal.

[0012] In one embodiment, braking according to the depression depth of the brake pedal and the depression depth of the accelerator pedal includes: when the duration of the zero opening degree of the accelerator pedal is greater than a preset time and the depression depth of the brake pedal is less than or equal to a second preset angle, adopting the electric motor braking mode.

[0013] In one embodiment, braking according to the depression depth of the brake pedal and the depression depth of the accelerator pedal further includes: when the opening degree of the accelerator pedal is zero and the depression depth of the brake pedal is greater than the second preset angle, adopting the electric motor braking mode and / or the hybrid braking mode.

[0014] According to another aspect of the present application, a braking energy recovery control device for construction machinery is provided, including: a switching module for switching the braking mode according to the depression depth of the brake pedal; wherein, the braking mode includes an electric motor braking mode and a hybrid braking mode; the hybrid braking mode includes electric motor braking and mechanical braking, and the electric motor braking mode includes electric motor braking; a recovery module for performing braking energy recovery according to the braking mode.

[0015] According to another aspect of the present application, a braking energy recovery control system for construction machinery is provided, including: a sensor for detecting the working parameters of the whole vehicle; a braking device including a brake pedal, an electric motor, and a mechanical brake; a recovery device connected to the braking device; and a controller connected to the sensor and the braking device for executing the braking energy recovery control method of any one of the above embodiments.

[0016] The braking energy recovery control method, device, and system provided by the present application combine two braking methods to form different braking modes, and switch the braking mode in real time according to the depression depth of the brake pedal. The simultaneous action of the two braking systems can reduce the braking distance and tire wear. At the same time, the electric motor braking can be used as redundant braking for mechanical braking, improving the safety of construction machinery. And the electric motor braking can achieve energy recovery, reduce energy consumption, and improve the braking stability of construction machinery. Description of the Drawings

[0017] By describing the embodiments of the present application in more detail in conjunction with the drawings, the above and other objects, features, and advantages of the present application will become more obvious. The drawings are used to provide a further understanding of the embodiments of the present application, and constitute a part of the specification. Together with the embodiments of the present application, they are used to explain the present application and do not constitute a limitation to the present application. In the drawings, the same reference numerals generally represent the same components or steps.

[0018] Figure 1 It is a schematic diagram of the principle of a braking energy recovery control system for construction machinery provided by an exemplary embodiment of the present application.

[0019] Figure 2 It is a schematic structural diagram of an exemplary crane provided by an exemplary embodiment of the present application.

[0020] Figure 3 It is a schematic flowchart of a braking energy recovery control method for construction machinery provided by an exemplary embodiment of the present application.

[0021] Figure 4 It is a schematic flowchart of a coasting energy recovery method provided by an exemplary embodiment of the present application.

[0022] Figure 5 It is a schematic flowchart of a braking energy recovery method provided by an exemplary embodiment of the present application.

[0023] Figure 6 It is a schematic structural diagram of a braking recovery control device for construction machinery provided by an exemplary embodiment of the present application.

[0024] Figure 7 It is a structural diagram of an electronic device provided by an exemplary embodiment of the present application.

[0025] Explanation of reference numerals: 21, cockpit; 22, weighing sensor; 23, vehicle controller; 24, motor controller; 25, braking device; 26, motor; 27, battery management system; 28, power device; 31, angle encoder; 32, speed sensor. Detailed implementation manners

[0026] Next, exemplary embodiments according to the present application will be described in detail with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments of the present application. It should be understood that the present application is not limited by the exemplary embodiments described herein.

[0027] Exemplary system

[0028] According to another aspect of the present application, a braking recovery control system for construction machinery is provided, including: a sensor for detecting the working parameters of the whole vehicle; a braking device including a brake pedal, a motor and a mechanical brake; a recovery device connected to the braking device; and a controller connected to the sensor and the braking device for executing the braking recovery control method for construction machinery provided by the present application.

[0029] The sensor may include an angle encoder, a weighing sensor, a speed sensor, etc. For example, the angle encoder is used to obtain the depression depth of the brake pedal, that is, the changed angle after the brake pedal is depressed; the weighing sensor can be used to detect the real-time load weight of the construction machinery during operation, and the speed sensor can be used to detect the real-time driving speed of the construction machinery. The construction machinery may include a crane, especially a reach stacker. The speed of an electric crane will travel at a high speed due to inertia under the conditions of no braking and no throttle, which is not conducive to operation. And the braking has always relied on mechanical braking, which also causes great losses to energy and tires.

[0030] Figure 1 It is a schematic principle diagram of a braking recovery control system for construction machinery provided by an exemplary embodiment of the present application, as Figure 1As shown, the controller may include a vehicle controller 23 and a motor 26 controller 24. The angle encoder 31, the weighing sensor 22, and the speed sensor 32 respectively transmit CAN signals to the vehicle controller 23. The vehicle controller 23 outputs CAN signals to the motor 26 controller 24, and then the motor 26 controller 24 outputs CAN signals to the battery management system 27.

[0031] Therefore, a closed-loop control is formed by the motor controller, the vehicle controller, the angle encoder, the weighing sensor, and the speed sensor. By detecting the angle of the current brake pedal and the load weight of the construction machinery, the optimal electric motor braking torque is calculated, and the braking torque is recovered. While ensuring the braking performance of the construction machinery, the energy consumption is reduced through energy recovery.

[0032] The construction machinery braking recovery control system provided by this application combines two braking methods to form different braking modes, and switches the braking mode in real time according to the depression depth of the brake pedal. The simultaneous action of the two braking systems can reduce the braking distance and tire wear. At the same time, the electric motor braking can be used as redundant braking for the mechanical braking, improving the safety of the construction machinery. And the electric motor braking can achieve energy recovery, reduce energy consumption, and improve the braking stability of the construction machinery.

[0033] Exemplary crane

[0034] Figure 2 is a schematic structural diagram of an exemplary crane provided by an exemplary embodiment of this application, as Figure 2As shown, the construction machinery provided by the present application may include a crane, which may be a reach stacker, and the crane may apply the construction machinery braking and energy recovery control system provided by the above embodiments. Among them, the controller may include a vehicle controller 23 and a motor 26 controller 24. Among them, the cockpit 21 is connected to the vehicle controller 23, and the cockpit 21 sends a braking instruction to the vehicle controller 23. The weighing sensor 22 sends the weighing information to the vehicle controller 23. The vehicle controller 23 sends a braking torque instruction to the braking device 25, and the braking device 25 calculates the braking torque and sends it to the power device 28. The power device 28 is used to provide kinetic energy for the crane. The vehicle controller 23 also sends a demand motor 26 braking instruction to the motor 26 controller 24, and the motor 26 controller 24 sends a torque instruction to the motor 26. The motor 26 outputs the motor 26 braking force to the power device 28, and the motor 26 also outputs a charging current to the battery management system 27. After receiving the braking torque and the motor 26 braking force, the power device 28 generates a vehicle speed feedback to the vehicle controller 23 for calculating the braking torque. During the braking and energy recovery of the motor 26, the battery in the battery management system 27 no longer outputs current. At this time, the driving resistance of the crane becomes the power for the rotation of the rotor of the motor 26, so that the action of cutting the magnetic induction line is realized inside the motor 26. The alternating current generated by the motor 26 is reversely charged to the battery pack after passing through the motor 26 controller 24 and the battery management system 27, realizing the braking energy recovery of the crane.

[0035] Exemplary method

[0036] Figure 3 is a schematic flow chart of a construction machinery braking and energy recovery control method provided by an exemplary embodiment of the present application, as Figure 3 shown, the construction machinery braking and energy recovery control method includes:

[0037] Step 100: Switch the braking mode according to the depression depth of the brake pedal.

[0038] Among them, the braking mode includes an electric motor braking mode and a hybrid braking mode; the hybrid braking mode includes electric motor braking and mechanical braking, and the electric motor braking mode includes electric motor braking.

[0039] Electric braking achieves the effect of accelerating the stop of the equipment through an electrical connection method opposite to the operation mode that drives the equipment to move; mechanical braking inhibits the existing movement of the equipment through physical mechanics. In this application, electric braking is added while mechanical braking is performed. By combining the two braking methods, different braking modes are formed, and the braking mode is switched in real time according to the depression depth of the brake pedal. The braking distance of mechanical braking already meets the national standard braking distance requirements, and the braking distance during the newly added single electric braking can also meet the national standard braking distance requirements. The simultaneous action of the two braking systems can reduce the braking distance and tire wear. At the same time, electric braking can be used as redundant braking for mechanical braking, improving the safety of construction machinery.

[0040] Step 200: Recover braking energy according to the braking mode.

[0041] By adding electric braking, the simultaneous action of the two braking systems can reduce the braking distance and tire wear. At the same time, electric braking can be used as redundant braking for mechanical braking, improving the safety of construction machinery. Moreover, when electric braking is involved, the system can also recover energy. During the electric braking recovery process, the battery in the battery management system no longer outputs current. At this time, the driving resistance of the construction machinery becomes the driving force for the rotation of the motor rotor, thus realizing the action of cutting magnetic induction lines inside the motor. The alternating current generated by the motor is rectified and charged back to the battery pack through the motor controller and the battery management system, realizing the recovery of braking energy.

[0042] In an embodiment, the above step 100 may include: when the depression depth of the brake pedal is greater than the first preset angle, switch to the hybrid braking mode; or when the depression depth of the brake pedal is less than or equal to the first preset angle, switch to the electric braking mode.

[0043] For example, the first preset angle may be twenty degrees. When the depression depth of the brake pedal is greater than twenty degrees, mechanical braking and electric braking can be used simultaneously. By combining the two braking methods, a better braking effect can be achieved, the braking distance can be shortened, and the negative impact caused by single braking can be reduced. When the depression depth of the brake pedal is less than or equal to twenty degrees, only the electric braking mode can be used. By using electric braking, the time of mechanical braking can be reduced, tire wear can be reduced, the maintenance time of the hydraulic braking system can be extended, and the use and maintenance costs of the product can be reduced. Therefore, by adjusting the braking mode according to the actual braking requirements, not only can braking energy be recovered, but also mechanical wear can be reduced.

[0044] Among them, when combined with mechanical braking, an electronically controlled brake proportional valve can be added to the hydraulic brake system to control the hydraulic ratio of the hydraulic brake system. For example, when the vehicle speed slows down and the staff does not adjust the pedal depth of the brake pedal in time, the electronically controlled brake proportional valve can automatically reduce the intervention ratio of the hydraulic brake system, thereby reducing energy consumption loss. Adding an electronically controlled brake proportional valve can increase the flexibility of the mechanical brake system, automatically adjust the intervention ratio of the mechanical brake when the vehicle speed slows down, reduce the mechanical braking time, reduce tire wear, and achieve the purpose of reducing mechanical energy consumption. At this time, reducing the intervention ratio of the hydraulic brake system is to reduce the pedal depth of the first preset angle in disguise, because when the pedal depth of the brake pedal is less than or equal to the first preset angle, there is no mechanical brake intervention. Therefore, when the vehicle speed slows down from fast, there is no need to manually adjust the pedal depth. The electronically controlled brake proportional valve adjusts the hydraulic system to regulate the intervention ratio of the mechanical brake, reducing the influence of human factors and further improving the energy recovery efficiency.

[0045] In one embodiment, the above step 200 may include: adjusting the braking torque of the motor according to the braking mode and the whole vehicle operating parameters; and performing braking energy recovery according to the braking torque.

[0046] Based on the vehicle operating parameters and braking mode collected by various sensors, the motor braking torque required for engineering machinery braking is calculated, the motor braking torque is adjusted in real time, and the motor braking torque is optimized. By adding motor braking, tire wear and mechanical brake use are reduced, thereby reducing maintenance costs. During the motor braking recovery process, the battery no longer outputs current. At this time, the driving resistance of the engineering machinery becomes the driving force for the rotation of the motor rotor, thereby realizing the action of cutting the magnetic flux lines inside the motor. The AC power generated by the motor is backcharged to the battery pack after passing through the motor controller and the battery controller to achieve vehicle braking energy recovery. For example, when driving with no throttle, a smaller motor braking torque is output according to the current vehicle speed, so that the vehicle decelerates and stops evenly, thereby improving the efficiency of kinetic energy recovery.

[0047] In one embodiment, the vehicle operating parameters include the current vehicle speed. Adjusting the braking torque of the motor according to the braking mode and the vehicle operating parameters may include: in the braking state, when the current vehicle speed is greater than the first preset vehicle speed, adjusting the braking torque of the motor according to the vehicle operating parameters.

[0048] For example, the first preset vehicle speed can be 3 km / h. When the current vehicle speed is greater than 3 km / h, electric motor braking can be adopted. When the vehicle speed of the construction machinery is lower than 3 km / h, the recoverable energy is limited. And to prevent the reverse movement of the construction machinery, braking recovery is not performed when the vehicle speed is lower than 3 km / h. Therefore, only when the current vehicle speed is greater than the first preset vehicle speed, the braking torque of the electric motor is calculated and the electric motor is made to intervene in braking. In the braking state, it can be expressed that in any braking mode, the construction machinery is in the braking state, or, when the construction machinery is in the braking state, it means that the construction machinery is in any braking mode.

[0049] In one embodiment, the vehicle operating parameters include weighing information, and the weighing information includes the current load of the construction machinery and the limit load of the construction machinery. In the braking state, when the current vehicle speed is greater than the first preset vehicle speed, adjusting the braking torque of the electric motor according to the vehicle operating parameters may include: in the braking state, when the current vehicle speed is greater than the first preset vehicle speed and less than or equal to the second preset vehicle speed, adjusting the braking torque of the electric motor according to the weighing information and the current vehicle speed; the braking torque of the electric motor is positively correlated with the current load, the braking torque of the electric motor is negatively correlated with the limit load, and the braking torque of the electric motor is positively correlated with the current vehicle speed; wherein, the second preset vehicle speed is greater than the first preset vehicle speed.

[0050] For example, the first preset vehicle speed can be 3 km / h, and the second preset vehicle speed is 15 km / h. When the current vehicle speed is greater than 3 km / h and less than or equal to 15 km / h, calculating the braking torque of the electric motor also needs to consider the current vehicle speed. The speed change of the construction machinery is detected in real time through a speed sensor, and the braking torque of the electric motor is adjusted in real time. When the electric motor speed is in the high-efficiency power generation area, the braking torque of the electric motor is appropriately increased to improve the power generation efficiency of the electric motor. When the vehicle speed is relatively low, the braking torque of the electric motor is reduced to ensure the smooth braking of the construction machinery during electric motor braking and reduce the sense of jerk.

[0051] At this time, the calculation of the braking torque of the electric motor can adopt the following calculation formula:

[0052] Wherein, W 1 represents the self-weight of the construction machinery, W 2 represents the current load of the construction machinery, W 3 represents the sum of the self-weight and the limit load of the construction machinery, N max represents the maximum torque of coasting braking; V represents the current vehicle speed.

[0053] That is to say, when the vehicle speed is within 15 km / h, the influence of the vehicle speed on braking also needs to be considered. By adding the current vehicle speed of the construction machinery to optimize the braking torque of the electric motor, the stability of the construction machinery can be improved or the power generation efficiency of the electric motor can be improved, bringing a safer driving environment for the driver of the construction machinery.

[0054] In one embodiment, the vehicle operating parameters include weighing information, and the weighing information includes the current load of the construction machinery and the limit load of the construction machinery. In the braking state, when the current vehicle speed is greater than a first preset vehicle speed, adjusting the braking torque of the motor according to the vehicle operating parameters may further include: in the braking state, when the current vehicle speed is greater than a second preset vehicle speed, adjusting the braking torque of the motor according to the weighing information; wherein, the second preset vehicle speed is greater than the first preset vehicle speed, the braking torque of the motor is positively correlated with the current load, and the braking torque of the motor is negatively correlated with the limit load.

[0055] For example, the first preset vehicle speed may be 3 km / h, and the second preset vehicle speed is 15 km / h. When the current vehicle speed is greater than 15 km / h, the braking torque of the motor can be calculated only based on the current load of the construction machinery, the limit load of the construction machinery, and the maximum torque of coasting braking, so that the motor can brake according to the actual situation of the construction machinery, preventing over-braking or insufficient braking energy.

[0056] The calculation of the braking torque of the motor can adopt the following calculation formula:

[0057] Wherein, W 1 represents the self-weight of the construction machinery, W 2 represents the current load of the construction machinery, W 3 represents the sum of the self-weight and the limit load of the construction machinery, N max represents the maximum torque of coasting braking.

[0058] That is to say, according to the current load of the construction machinery, the limit load of the construction machinery, and the self-weight of the construction machinery, the ratio of the current total weight of the construction machinery to the limit total weight of the construction machinery is calculated, and the braking torque of the motor is optimized according to this ratio. When the vehicle speed of the construction machinery reaches the recoverable condition, electric braking can be added to improve the energy recovery rate and reduce energy consumption. When the vehicle speed of the construction machinery reaches the recoverable condition and the vehicle speed is relatively fast (for example, greater than 15 km / h), the braking torque of the motor can be determined only based on the current load of the construction machinery and the limit load of the construction machinery. At this time, the value of the current actual vehicle speed does not need to be considered. According to different load weights and the depression depth of the brake pedal, the optimal braking torque is calculated to achieve the optimal braking recovery efficiency.

[0059] In one embodiment, the vehicle operating parameters include the current vehicle speed. Adjusting the braking torque of the motor according to the braking mode and the vehicle operating parameters may further include: in the braking state, when the current vehicle speed is less than or equal to the first preset vehicle speed, no braking energy recovery is performed.

[0060] For example, the first preset vehicle speed can be 3 km / h. When the vehicle speed of the construction machinery is lower than 3 km / h, the recoverable energy is limited. Also, to prevent the construction machinery from moving backward, no braking energy recovery is performed when the vehicle speed is lower than 3 km / h. Therefore, only when the current vehicle speed is greater than the first preset vehicle speed, the braking torque of the motor is calculated and the motor is allowed to intervene in braking.

[0061] In one embodiment, before the above step 100, the construction machinery braking recovery control method may further include: braking according to the depression depth of the brake pedal and the opening degree of the accelerator pedal.

[0062] In addition to braking solely based on the depression depth of the brake pedal, the opening degree of the accelerator pedal can also be used as a judgment condition to select the braking method. For example, when the brake pedal has a depression depth, that is, when the driver steps on the brake pedal, the opening degree of the accelerator pedal must be zero. At this time, only the braking mode needs to be considered based on the depression depth of the brake pedal. When the brake pedal has no depression depth, two situations will occur, including the opening degree of the accelerator pedal being zero and the opening degree of the accelerator pedal not being zero. Therefore, when the opening degree of the accelerator pedal is not zero, no braking is required. When the opening degree of the accelerator pedal is zero, the motor braking can also be selected according to the current vehicle speed. While braking, energy recovery is performed, which not only achieves the braking effect but also reduces energy consumption.

[0063] The method of motor braking is scientific, which can reduce equipment damage, and is sensitive in response. Most importantly, energy recovery can be performed. Therefore, when the opening degree of the accelerator pedal of the construction machinery is zero, that is, when the construction machinery is coasting, small-torque coasting braking is performed, which can not only perform braking energy recovery but also cause no sense of jerk to the driver, improving the stability of the construction machinery.

[0064] In one embodiment, braking according to the depression depth of the brake pedal and the depression depth of the accelerator pedal may include: when the duration of the zero opening degree of the accelerator pedal is greater than the preset time and the depression depth of the brake pedal is less than or equal to the second preset angle, the motor braking mode is adopted.

[0065] For example, the preset time can be three seconds and the second preset angle can be zero degree. When the duration of the zero opening degree of the accelerator pedal is greater than three seconds and the depression depth of the brake pedal is less than or equal to zero, at this time, the construction machinery is coasting with the throttle off, and only the motor braking is used to perform small-torque coasting braking on the construction machinery, which can not only perform braking energy recovery but also cause no sense of jerk to the driver, improving the stability of the construction machinery.

[0066] In one embodiment, braking according to the depression depth of the brake pedal and the depression depth of the accelerator pedal may further include: when the opening of the accelerator pedal is zero and the depression depth of the brake pedal is greater than a second preset angle, adopting an electric motor braking mode and / or a hybrid braking mode.

[0067] For example, the second preset angle may be zero degrees. When the opening of the accelerator pedal is zero and the depression depth of the brake pedal is greater than zero, an electric motor braking mode or a hybrid braking mode may be adopted. The method for selecting a braking mode when the depression depth of the brake pedal is greater than zero may adopt the conditions for switching the braking mode provided in the above embodiments.

[0068] Adopting the engineering machinery braking recovery control method provided in the above embodiments, the single - time braking recovery power efficiency of the engineering machinery reaches 53% (vehicle speed from 20 km / h to 0 km / h). Under comprehensive working conditions, the power recovery efficiency reaches 10%, greatly reducing the energy consumption caused by single mechanical braking and reducing tire wear.

[0069] Combining the engineering machinery braking recovery control methods provided in the above embodiments, it can be summarized into two energy recovery functions, namely braking energy recovery and coasting energy recovery. When the opening of the accelerator pedal is zero and the duration is greater than a preset time, and the depression depth of the brake pedal is less than or equal to zero, coasting energy recovery can be performed. When the opening of the accelerator pedal is zero and the depression depth of the brake pedal is greater than zero, braking energy recovery can be performed.

[0070] For example, Figure 4 is a schematic flowchart of the coasting energy recovery method provided by an exemplary embodiment of the present application. As Figure 4 shown, first, it is determined whether the opening of the accelerator pedal being equal to zero is greater than three seconds (step 51). When the accelerator pedal has no input (i.e., the opening of the accelerator pedal is zero) for more than three seconds and the current vehicle speed is greater than 3 km / h (step 52), the engineering machinery performs coasting braking (step 53), that is, the electric motor braking is intervened during coasting. Then, it is determined whether the current vehicle speed is greater than 15 km / h (step 54). When the current vehicle speed is greater than 15 km / h, according to the current load of the engineering machinery, the ultimate load of the engineering machinery, and the self - weight of the engineering machinery, the ratio of the current total weight of the engineering machinery to the ultimate total weight of the engineering machinery is calculated, and the electric motor braking torque is optimized according to this ratio, that is, using the formula: (step 55); where W 1 represents the self - weight of the engineering machinery, W 2 represents the current load of the engineering machinery, W 3 represents the sum of the self - weight and the ultimate load of the engineering machinery, and N maxIndicates the maximum torque of coasting braking to calculate the motor braking torque. When the current vehicle speed is greater than 3 km / h and less than 15 km / h, the current vehicle speed also needs to be considered when calculating the motor braking torque, that is, the formula (Step 56); where, W 1 Indicates the self-weight of the construction machinery, W 2 Indicates the current load of the construction machinery, W 3 Indicates the sum of the self-weight and the limit load of the construction machinery, N max Indicates the maximum torque of coasting braking; V represents the current vehicle speed to calculate the motor braking torque. When the current vehicle speed is less than 3 km / h, no braking energy recovery is required. When the opening of the accelerator pedal is zero but the duration is less than or equal to the preset time, the current motor torque remains unchanged (Step 57), that is, the current motor torque may be zero and no braking is performed temporarily.

[0071] For example, Figure 5 is a schematic flow chart of the braking energy recovery method provided by an exemplary embodiment of the present application. As Figure 5 shown, first, it is judged whether the depression depth of the brake pedal is greater than zero (Step 41), and then it is judged whether the depression depth of the brake pedal is less than twenty degrees (Step 42). When the depression depth of the brake pedal is greater than zero and less than twenty degrees, it is judged whether the current vehicle speed of the construction machinery is greater than 3 km / h (Step 44). When the vehicle speed is greater than 3 km / h, the construction machinery performs a single motor braking mode (Step 45). When the current vehicle speed is greater than 15 km / h, according to the current load of the construction machinery, the limit load of the construction machinery, and the self-weight of the construction machinery, the ratio of the current total weight of the construction machinery to the limit total weight of the construction machinery is calculated, and the motor braking torque is optimized according to this ratio, that is, the formula: (Step 47); where, W 1 Indicates the self-weight of the construction machinery, W 2 Indicates the current load of the construction machinery, W 3 Indicates the sum of the self-weight and the limit load of the construction machinery, N max Indicates the maximum torque of coasting braking to calculate the motor braking torque. When the current vehicle speed is greater than 3 km / h and less than 15 km / h, the current vehicle speed also needs to be considered when calculating the motor braking torque, that is, the formula (Step 48); where, W 1 Indicates the self-weight of the construction machinery, W 2 Indicates the current load of the construction machinery, W 3 Indicates the sum of the self-weight and the limit load of the construction machinery, N max Indicates the maximum torque of coasting braking; V represents the current vehicle speed to calculate the motor braking torque.

[0072] When the depression depth of the brake pedal is greater than 20 degrees, a hybrid braking mode is adopted, that is, mechanical braking is added (step 43), and the two braking methods are started simultaneously to reduce the braking distance. In the hybrid braking mode, the braking method of the electric motor braking is the same as the judgment method of the above single electric motor braking mode, that is, after the mechanical braking intervenes, the process of steps 44 to 48 is continued to be executed.

[0073] When the depression depth of the brake pedal is less than or equal to 0 degree, the current motor torque is maintained unchanged (step 49), that is, the current motor torque may be zero and braking is not performed temporarily.

[0074] Exemplary device

[0075] Figure 6 is a schematic structural diagram of a construction machinery braking recovery control device provided by an exemplary embodiment of the present application. As Figure 6 shown, the construction machinery braking recovery control device 8 includes: a switching module 81 for switching the braking mode according to the depression depth of the brake pedal; wherein, the braking mode includes an electric motor braking mode and a hybrid braking mode; the hybrid braking mode includes electric motor braking and mechanical braking, and the electric motor braking mode includes electric motor braking; a recovery module 82 for performing braking energy recovery according to the braking mode.

[0076] The construction machinery braking recovery control device provided by the present application combines two braking methods to form different braking modes, and switches the braking mode in real time according to the depression depth of the brake pedal. The simultaneous action of the two braking systems can reduce the braking distance and tire wear. At the same time, the electric motor braking can be used as redundant braking for the mechanical braking, improving the safety of the construction machinery. And the electric motor braking can realize energy recovery, reduce energy consumption, and improve the braking stability of the construction machinery.

[0077] In an embodiment, the above switching module 81 may be configured as: when the depression depth of the brake pedal is greater than a first preset angle, switch to the hybrid braking mode; or when the depression depth of the brake pedal is less than or equal to the first preset angle, switch to the electric motor braking mode.

[0078] In an embodiment, the above adjustment module 82 may be configured as: adjusting the braking torque of the motor according to the braking mode and the vehicle operating parameters; performing braking energy recovery according to the braking torque.

[0079] In an embodiment, the above adjustment module 82 may also be configured as: when the current vehicle speed is greater than a first preset vehicle speed in the braking state, adjusting the braking torque of the motor according to the vehicle operating parameters.

[0080] In one embodiment, the above-mentioned adjustment module 82 may also be configured to: in a braking state, when the current vehicle speed is greater than a first preset vehicle speed and less than or equal to a second preset vehicle speed, adjust the braking torque of the motor according to the weighing information and the current vehicle speed; the braking torque of the motor is positively correlated with the current load, the braking torque of the motor is negatively correlated with the limit load, and the braking torque of the motor is positively correlated with the current vehicle speed; wherein, the second preset vehicle speed is greater than the first preset vehicle speed.

[0081] In one embodiment, the above-mentioned adjustment module 82 may also be configured to: in a braking state, when the current vehicle speed is greater than the second preset vehicle speed, adjust the braking torque of the motor according to the weighing information; wherein, the second preset vehicle speed is greater than the first preset vehicle speed, the braking torque of the motor is positively correlated with the current load, and the braking torque of the motor is negatively correlated with the limit load.

[0082] In one embodiment, the above-mentioned adjustment module 82 may also be configured to: in a braking state, when the current vehicle speed is less than or equal to the first preset vehicle speed, no braking energy recovery is performed.

[0083] In one embodiment, the above-mentioned engineering machinery braking recovery control device 8 may also be configured to: perform braking according to the depression depth of the brake pedal and the opening degree of the accelerator pedal.

[0084] In one embodiment, the above-mentioned engineering machinery braking recovery control device 8 may also be configured to: when the duration of the opening degree of the accelerator pedal being zero is greater than a preset time, and the depression depth of the brake pedal is less than or equal to a second preset angle, adopt an electric motor braking mode.

[0085] In one embodiment, the above-mentioned engineering machinery braking recovery control device 8 may also be configured to: when the opening degree of the accelerator pedal is zero and the depression depth of the brake pedal is greater than the second preset angle, adopt an electric motor braking mode and / or a hybrid braking mode.

[0086] Exemplary electronic device

[0087] Next, refer to Figure 7 to describe the electronic device according to an embodiment of the present application. The electronic device may be any one or both of the first device and the second device, or a stand-alone device independent of them, and the stand-alone device may communicate with the first device and the second device to receive the input signals collected from them.

[0088] Figure 7 The block diagram of the electronic device according to an embodiment of the present application is illustrated.

[0089] As Figure 7 shown, the electronic device 10 includes one or more processors 11 and a memory 12.

[0090] The processor 11 can be a central processing unit (CPU) or other forms of processing units with data processing capabilities and / or instruction execution capabilities, and can control other components in the electronic device 10 to perform desired functions.

[0091] The memory 12 can include one or more computer program products, and the computer program products can include various forms of computer-readable storage media, such as volatile memory and / or non-volatile memory. The volatile memory can include, for example, random access memory (RAM) and / or cache memory, etc. The non-volatile memory can include, for example, read-only memory (ROM), hard disk, flash memory, etc. One or more computer program instructions can be stored on the computer-readable storage media, and the processor 11 can run the program instructions to implement the engineering machinery braking recovery control method of various embodiments of the present application described above and / or other desired functions. Various contents such as input signals, signal components, noise components, etc. can also be stored in the computer-readable storage media.

[0092] In one example, the electronic device 10 can further include: an input device 13 and an output device 14, and these components are interconnected through a bus system and / or other forms of connection mechanisms (not shown).

[0093] When the electronic device is a stand-alone device, the input device 13 can be a communication network connector for receiving the collected input signals from the first device and the second device.

[0094] In addition, the input device 13 can further include, for example, a keyboard, a mouse, and so on.

[0095] The output device 14 can output various information to the outside, including the determined distance information, direction information, etc. The output device 14 can include, for example, a display, a speaker, a printer, and a communication network and its connected remote output devices, and so on.

[0096] Of course, for simplicity, Figure 7 only some of the components related to the present application in the electronic device 10 are shown, and components such as buses, input / output interfaces, etc. are omitted. In addition, according to specific application scenarios, the electronic device 10 can further include any other appropriate components.

[0097] The computer program product may be written in any combination of one or more programming languages for executing the program code of the operations of the embodiments of the present application. The programming languages include object-oriented programming languages such as Java, C++, etc., and also include conventional procedural programming languages such as the "C" language or similar programming languages. The program code may be executed entirely on the user computing device, partially on the user device, executed as a stand-alone software package, partially on the user computing device and partially on a remote computing device, or entirely on a remote computing device or server.

[0098] The computer-readable storage medium may adopt any combination of one or more readable media. The readable media may be a readable signal medium or a readable storage medium. The readable storage medium may, for example, include but is not limited to an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any combination of the above. More specific examples (non-exhaustive list) of the readable storage medium include: an electrical connection having one or more wires, a portable disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the above.

[0099] The above description has been given for purposes of illustration and description. In addition, this description is not intended to limit the embodiments of the present application to the forms disclosed herein. Although multiple example aspects and embodiments have been discussed above, those skilled in the art will recognize certain variations, modifications, changes, additions, and sub-combinations thereof.

Claims

1. A control method for braking energy recovery of construction machinery, characterized in that, it includes: switching the braking mode according to the depression depth of the brake pedal; wherein, the braking mode includes an electric motor braking mode and a hybrid braking mode; the hybrid braking mode includes electric motor braking and mechanical braking, and the electric motor braking mode includes electric motor braking; performing braking energy recovery according to the braking mode; the performing braking energy recovery according to the braking mode includes: adjusting the braking torque of the motor according to the braking mode and the vehicle operating parameters; performing the braking energy recovery according to the braking torque; the vehicle operating parameters include the current vehicle speed, and the adjusting the braking torque of the motor according to the braking mode and the vehicle operating parameters includes: in the braking state, when the current vehicle speed is greater than a first preset vehicle speed, adjusting the braking torque of the motor according to the vehicle operating parameters; the vehicle operating parameters include weighing information, and the weighing information includes the current load of the construction machinery and the limit load of the construction machinery. In the braking state, when the current vehicle speed is greater than the first preset vehicle speed, the adjusting the braking torque of the motor according to the vehicle operating parameters includes: in the braking state, when the current vehicle speed is greater than the first preset vehicle speed and less than or equal to a second preset vehicle speed, adjusting the braking torque of the motor according to the weighing information and the current vehicle speed; the braking torque of the motor is positively correlated with the current load, the braking torque of the motor is negatively correlated with the limit load, and the braking torque of the motor is positively correlated with the current vehicle speed; wherein, the second preset vehicle speed is greater than the first preset vehicle speed.

2. The control method for braking energy recovery of construction machinery according to claim 1, characterized in that, the switching the braking mode according to the depression depth of the brake pedal includes: when the depression depth of the brake pedal is greater than a first preset angle, switching to the hybrid braking mode; or when the depression depth of the brake pedal is less than or equal to the first preset angle, switching to the electric motor braking mode.

3. The control method for braking energy recovery of construction machinery according to claim 1, characterized in that, the vehicle operating parameters include weighing information, and the weighing information includes the current load of the construction machinery and the limit load of the construction machinery. In the braking state, when the current vehicle speed is greater than the first preset vehicle speed, the adjusting the braking torque of the motor according to the vehicle operating parameters further includes: in the braking state, when the current vehicle speed is greater than the second preset vehicle speed, adjusting the braking torque of the motor according to the weighing information; wherein, the second preset vehicle speed is greater than the first preset vehicle speed, and the braking torque of the motor is positively correlated with the current load and negatively correlated with the limit load.

4. The control method for braking energy recovery of construction machinery according to claim 1, characterized in that, the vehicle operating parameters include the current vehicle speed, and the adjusting the braking torque of the motor according to the braking mode and the vehicle operating parameters further includes: In the braking state, when the current vehicle speed is less than or equal to the first preset vehicle speed, the braking energy recovery is not performed.

5. The construction machinery braking recovery control method according to claim 1, wherein, before switching the braking mode according to the depression depth of the braking pedal, it further includes: performing braking according to the depression depth of the braking pedal and the opening degree of the accelerator pedal.

6. The construction machinery braking recovery control method according to claim 5, wherein, performing braking according to the depression depth of the braking pedal and the depression depth of the accelerator pedal includes: when the duration of the zero opening degree of the accelerator pedal is greater than the preset time and the depression depth of the braking pedal is less than or equal to the second preset angle, adopting the electric motor braking mode.

7. The construction machinery braking recovery control method according to claim 5, wherein, performing braking according to the depression depth of the braking pedal and the depression depth of the accelerator pedal further includes: when the opening degree of the accelerator pedal is zero and the depression depth of the braking pedal is greater than the second preset angle, adopting the electric motor braking mode and / or the hybrid braking mode.

8. A construction machinery braking recovery control device, wherein, it includes: a switching module for switching the braking mode according to the depression depth of the braking pedal; wherein, the braking mode includes an electric motor braking mode and a hybrid braking mode; the hybrid braking mode includes electric motor braking and mechanical braking, and the electric motor braking mode includes electric motor braking; a recovery module for performing braking energy recovery according to the braking mode; performing braking energy recovery according to the braking mode includes: adjusting the braking torque of the electric motor according to the braking mode and the vehicle operating parameters; performing the braking energy recovery according to the braking torque; the vehicle operating parameters include the current vehicle speed, and adjusting the braking torque of the electric motor according to the braking mode and the vehicle operating parameters includes: in the braking state, when the current vehicle speed is greater than the first preset vehicle speed, adjusting the braking torque of the electric motor according to the vehicle operating parameters; the vehicle operating parameters include weighing information, and the weighing information includes the current load of the construction machinery and the limit load of the construction machinery. In the braking state, when the current vehicle speed is greater than the first preset vehicle speed, adjusting the braking torque of the electric motor according to the vehicle operating parameters includes: in the braking state, when the current vehicle speed is greater than the first preset vehicle speed and less than or equal to the second preset vehicle speed, adjusting the braking torque of the electric motor according to the weighing information and the current vehicle speed; the braking torque of the electric motor is positively correlated with the current load, the braking torque of the electric motor is negatively correlated with the limit load, and the braking torque of the electric motor is positively correlated with the current vehicle speed; wherein, the second preset vehicle speed is greater than the first preset vehicle speed.

9. A construction machinery braking recovery control system, wherein, it includes: a sensor for detecting vehicle operating parameters; a braking device, and the braking device includes a braking pedal, an electric motor and a mechanical brake; A recovery device, the recovery device being connected to the braking device; And A controller, the controller being connected to the sensor and the braking device, and being configured to execute the construction machinery braking recovery control method according to any one of claims 1-7 above.

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