Control method, device and system for preventing stalling and flameout of working machine

Abstract

The application discloses a control method, device and system for preventing speed drop and flameout of a working machine, and belongs to the technical field of working machine control. The method obtains a whole vehicle gear, a whole vehicle gear rotating speed and an actual rotating speed, determines a gear interval to which the whole vehicle belongs, calculates a rotating speed difference value of the whole vehicle gear rotating speed and the actual rotating speed, judges whether the current working machine is in a speed drop state according to the rotating speed difference value, determines a fuzzy PID output value according to the current whole vehicle gear and the actual rotating speed when the current working machine is in the speed drop state, determines a control current change range of a flow control hydraulic valve of the current working machine according to the rotating speed difference value and the gear interval, determines a control current value of the flow control hydraulic valve according to the fuzzy PID output value and the control current change range, and controls opening and closing of the flow control hydraulic valve according to the control current. The flow output is adjusted by controlling the flow control hydraulic valve, and the executing element still receives a certain torque when the speed drops.

Description

Technical Field

[0001] This application relates to the field of operating machinery control technology, specifically to a control method for preventing speed drop and engine stall of operating machinery, a control device for preventing speed drop and engine stall of operating machinery, a control posture for preventing speed drop and engine stall of operating machinery, an operating machine, and a machine-readable storage medium. Background Technology

[0002] There is a type of operational machinery whose traveling mechanism and actuators are controlled by a hydraulic system. During operation, due to factors such as the materials being worked on or the working conditions, this type of machinery often encounters drastic and frequent changes in load torque. This results in different engine load power at different gears, and the actual engine speed continuously decreases due to the load, sometimes even leading to engine stalling.

[0003] Traditional engine stall prevention systems primarily rely on engine speed. When the engine is in an abnormal operating state, appropriate degraded measures are implemented. However, under heavy loads, if the engine speed decreases beyond a certain threshold, stalling may still occur.

[0004] Traditional hydraulic systems for construction machinery are often equipped with load-sensitive pumps or pressure compensation valves. When excessive engine load is detected, the pump's displacement or flow rate is automatically reduced to prioritize stable engine speed. However, this can result in insufficient power from the actuators, failing to achieve the desired output effect. Summary of the Invention

[0005] The purpose of this application is to provide a control method, device, and system for preventing speed drop and engine stall in operating machinery, in order to solve the shortcomings of existing technologies where the engine of operating machinery is prone to speed drop and stall during operation.

[0006] To achieve the above objectives, the first aspect of this application provides a control method for preventing speed drop and engine stall of operating machinery, the method comprising: Obtain the vehicle's gear position, gear speed, and actual speed; Determine the gear range to which the vehicle belongs; Calculate the speed difference between the vehicle's gear position speed and the actual speed; Determine whether the current operating machinery is in a state of slowdown based on the speed difference value; When the current working machinery is in a deceleration state, the fuzzy PID output value is determined based on the current gear position and actual speed of the vehicle. The range of control current variation of the flow control hydraulic valve of the current working machine is determined based on the speed difference and the gear range. The control current value of the flow control hydraulic valve is determined based on the fuzzy PID output value and the control current variation range. The flow control hydraulic valve is opened and closed according to the control current.

[0007] Based on the above technical means, the vehicle is divided into different gear ranges. When the working machinery is in a deceleration state, different control current change ranges of the flow control hydraulic valve are set according to different deceleration conditions. Then, the control current value of the flow control hydraulic valve is calculated based on the output value of fuzzy PID control and the control current change range to control the flow control hydraulic valve. By controlling the flow control hydraulic valve to adjust the flow output, it can ensure that the actuator still receives a certain torque to achieve the desired output effect when decelerating, so that more engine power is used to maintain its own speed, thereby avoiding engine deceleration and stalling.

[0008] In some feasible embodiments, determining the control current value of the flow control hydraulic valve based on the fuzzy PID output value and the control current variation range includes: Obtain the adjustment range of fuzzy PID control; Calculate the first difference between the fuzzy PID output value and the lower limit of the adjustment range, and the second difference between the upper limit and the lower limit of the adjustment range; Calculate the ratio of the first difference to the second difference; The product of the proportional value and the maximum value of the control current variation range is calculated as the control current value.

[0009] In some feasible embodiments, determining the control current variation range of the flow control hydraulic valve of the current working machinery based on the speed difference and the gear range includes: If the gear range is a low speed gear and the speed difference is greater than the third threshold, then the control current variation range of the flow control hydraulic valve of the current working machine is determined to be the first preset range. If the gear range is a low speed gear, and the speed difference is greater than the fourth threshold and less than or equal to the third threshold, then the control current variation range of the flow control hydraulic valve of the current working machine is determined to be the second preset range. If the gear range is a low speed gear, and the speed difference is greater than the second threshold and less than or equal to the fourth threshold, then the control current variation range of the flow control hydraulic valve of the current working machine is determined to be the third preset range. If the gear range is a high-speed gear and the speed difference is greater than the third threshold, then the control current variation range of the flow control hydraulic valve of the current working machine is determined to be the fourth preset range. If the gear range is a high-speed gear, and the speed difference is greater than the fourth threshold and less than or equal to the third threshold, then the control current variation range of the flow control hydraulic valve of the current working machine is determined to be the fifth preset range. If the gear range is a high-speed gear, and the speed difference is greater than the second threshold and less than or equal to the fourth threshold, then the control current variation range of the flow control hydraulic valve of the current working machine is determined to be the third preset range.

[0010] In some feasible embodiments, determining whether the current operating machinery is in a speed-down state based on the speed difference includes: The speed difference is compared with the second threshold. If the speed difference is greater than the second threshold, it is determined that the current working machinery is in a speed-down state.

[0011] In some feasible embodiments, determining the gear range to which the vehicle belongs includes: Compare the vehicle's gear speed with a preset speed threshold. If the vehicle's gear speed is less than or equal to the preset speed threshold, the vehicle is in a low gear; otherwise, the vehicle is in a high gear. Alternatively, compare the actual gear position corresponding to the gear adjustment device with the preset gear position. If the actual gear position is less than or equal to the preset gear position, the vehicle is in a low gear position; otherwise, the vehicle is in a high gear position.

[0012] In some feasible embodiments, the fuzzy PID output value is determined based on the current vehicle gear and the actual engine speed, including: Obtain the speed-gear relationship table for fuzzy PID control; The target speed output of the fuzzy PID control is obtained by looking up the gear-speed relationship table based on the current gear position of the vehicle. Fuzzy PID control is performed based on the target speed output value and the actual speed, and the fuzzy PID output value is output.

[0013] In some feasible embodiments: after calculating the speed difference between the vehicle's gear position speed and the actual speed, the method further includes: The control current loading curve of the flow control hydraulic valve is determined based on the speed difference. After determining the control current value of the flow-controlled hydraulic valve, the valve is opened and closed according to the control current and the current loading curve. Setting the current loading curve allows adjustment of the flow-controlled hydraulic valve's operating rate, protecting hydraulic components.

[0014] A second aspect of this application provides a control device for preventing speed drop and engine stall of operating machinery, the device comprising: The data acquisition unit is used to acquire the vehicle's gear position, the vehicle's gear speed, and the actual speed. The gear analysis unit is used to determine the gear range to which the vehicle belongs; The first calculation unit is used to calculate the speed difference between the vehicle's gear speed and the actual speed. The speed drop analysis unit is used to determine whether the current operating machinery is in a speed drop state based on the speed difference value. The fuzzy PID unit is used to determine the fuzzy PID output value based on the current gear and actual speed of the vehicle when the current working machinery is in a deceleration state. The current parameter determination unit allows the user to determine the range of control current variation of the flow control hydraulic valve of the current working machine based on the speed difference and the gear range. A current determination unit is used to determine the control current value of the flow control hydraulic valve based on the fuzzy PID output value and the control current variation range. An execution unit is used to control the opening and closing of the flow control hydraulic valve according to the control current.

[0015] The third aspect of this application provides a control system for preventing speed drop and engine stall in operating machinery. The system includes: a gear shifting device, a controller, a speed sensor, a traveling device, an engine, a gear pump, an actuator, and an electronically controlled multi-way valve. The gear shifting device is connected to the engine via a CAN bus. The engine drives the gear pump to work. The gear pump transmits energy to the traveling device and the actuator through a hydraulic circuit and the electronically controlled multi-way valve to drive the traveling device and the actuator to move. The speed sensor and the gear shifting device are electrically connected to the controller. The system also includes: a flow control hydraulic valve, which is installed in the hydraulic circuit between the gear pump and the electronically controlled multi-way valve. The control terminal of the flow control hydraulic valve is connected to the controller. The controller is also used to: acquire the vehicle's gear position, the vehicle's gear speed, and the actual speed; determine the gear range to which the vehicle belongs; calculate the speed difference between the vehicle's gear speed and the actual speed; determine whether the current working machinery is in a deceleration state based on the speed difference; when the current working machinery is in a deceleration state, determine the fuzzy PID output value based on the current vehicle gear position and the actual speed; determine the control current variation range of the flow control hydraulic valve of the current working machinery based on the speed difference and the gear range; determine the control current value of the flow control hydraulic valve based on the fuzzy PID output value and the control current variation range; and control the opening and closing of the flow control hydraulic valve based on the control current.

[0016] Based on the aforementioned technical means, a flow control hydraulic valve is added to the control system. The controller uses a control method that divides the entire vehicle into different gear ranges. When the working machinery is in a deceleration state, different control current variation ranges for the flow control hydraulic valve are set according to different deceleration conditions. Then, based on the output value of fuzzy PID control and the control current variation range, the control current value of the flow control hydraulic valve is calculated to control the flow control hydraulic valve. By controlling the flow control hydraulic valve to adjust the flow output, it is possible to ensure that the actuator still receives a certain torque to achieve the desired output effect when decelerating, so that more engine power is used to maintain its own speed, thereby avoiding engine deceleration and stalling.

[0017] The fourth aspect of this application provides a working machine that uses the aforementioned control method for preventing speed drop and engine stall.

[0018] The fifth aspect of this application provides a machine-readable storage medium storing instructions for causing a machine to perform the aforementioned control method for preventing machine speed drop and engine stall.

[0019] Through the above technical solution, the method divides the vehicle into different gear ranges. When the working machinery is in a deceleration state, different control current change ranges of the flow control hydraulic valve are set according to different deceleration conditions. Then, based on the output value of fuzzy PID control and the control current change range, the control current value of the flow control hydraulic valve is calculated to control the flow control hydraulic valve. By controlling the flow control hydraulic valve to adjust the flow output, it can ensure that the actuator still receives a certain torque to achieve the desired output effect when decelerating, so that more engine power is used to maintain its own speed, thereby avoiding engine deceleration and stalling.

[0020] Other features and advantages of the embodiments of this application will be described in detail in the following detailed description section. Attached Figure Description

[0021] The accompanying drawings are provided to further illustrate the embodiments of this application and form part of the specification. They are used together with the following detailed description to explain the embodiments of this application, but do not constitute a limitation on the embodiments of this application. In the drawings: Figure 1 This illustration schematically shows the steps of a control method for preventing speed drop and engine stall of a work machine according to an embodiment of this application. Figure 2 The diagram schematically illustrates a control system for preventing speed drop and engine stall of a work machine according to an embodiment of this application. Figure 3 The schematic diagram illustrates a flow chart of a control method for preventing speed drop and engine stall of a work machine according to an embodiment of this application. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are only for illustration and explanation of the embodiments of this application and are not intended to limit the embodiments of this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0023] It should be noted that the acquisition, transmission, storage, use, and processing of data in the technical solution of this application all comply with relevant laws and regulations. In the embodiments of this application, certain existing industry solutions such as software, components, and models may be mentioned. These should be considered exemplary, intended only to illustrate the feasibility of implementing the technical solution of this application, and do not imply that the applicant has already used or necessarily used such solutions.

[0024] It should be noted that if the embodiments of this application involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicators will also change accordingly.

[0025] Furthermore, if the embodiments of this application involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, features defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the technical solutions of various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. If the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed in this application.

[0026] Figure 1 The illustration schematically depicts the steps of a control method for preventing speed drop and engine stalling of operating machinery according to an embodiment of this application. Figure 1 As shown in the figure, this application provides a control method for preventing speed drop and engine stall of operating machinery. The method may include the following steps.

[0027] S1: Obtain the vehicle gear position, the vehicle gear speed, and the actual speed. In some feasible embodiments, the vehicle gear position is sent to the controller by the gear adjustment device, the vehicle gear speed is the speed that the traveling device should reach corresponding to the current vehicle gear, and the actual speed is the speed of the traveling device detected by the speed sensor. The vehicle gear position and the corresponding vehicle gear speed are stored in the controller's storage space for retrieval and use.

[0028] S2: Determine the gear range to which the vehicle belongs. In this embodiment, the gear range includes low-speed gears and high-speed gears.

[0029] In some feasible embodiments, the gear range of the vehicle can be determined by comparing the vehicle's gear speed with a preset speed threshold. If the vehicle's gear speed is less than or equal to the preset speed threshold, the vehicle is in a low-speed gear; otherwise, the vehicle is in a high-speed gear. For example, assuming the preset speed threshold is 200 r / min, then when the vehicle's gear speed is 150 r / min, it is in a low-speed gear; when the vehicle's gear speed is 500 r / min, it is in a high-speed gear.

[0030] In other feasible embodiments, the gear range of the vehicle can be determined by comparing the actual gear position corresponding to the gear adjustment device with the preset gear position. If the actual gear position is less than or equal to the preset gear position, the vehicle belongs to a low-speed gear; otherwise, the vehicle belongs to a high-speed gear. For example, assuming the preset gear position is 4th gear, then when the actual gear position is 1-4, it belongs to a low-speed gear; when the actual gear position is 5-10, it belongs to a high-speed gear.

[0031] S3: Calculate the speed difference between the vehicle's gear position speed and the actual speed.

[0032] S4: Determine whether the current operating machinery is in a speed drop state based on the speed difference value.

[0033] In some feasible embodiments, determining whether the current operating machinery is in a speed-down state based on the speed difference includes: The speed difference is compared with a second threshold. If the speed difference is greater than the second threshold, the machine is determined to be in a speed-reducing state. In this embodiment, the second threshold is set according to the engine speed control requirements. The smaller the second threshold, the greater the control precision and the higher the control frequency; the larger the second threshold, the smaller the control precision and the lower the control frequency.

[0034] S5: When the current working machinery is in a deceleration state, determine the fuzzy PID output value based on the current gear position and actual speed of the vehicle.

[0035] In some feasible embodiments, the fuzzy PID output value is determined based on the current vehicle gear and the actual engine speed, including: Obtain the fuzzy PID control gear-speed relationship table, which records the correspondence between the vehicle's gear positions and the target output speed values ​​of the fuzzy PID control. This table is stored in the controller's storage space. The target output speed value of the fuzzy PID control is usually lower than the vehicle's gear-speed to prevent overshoot.

[0036] The target speed value for fuzzy PID control output is obtained by looking up the gear-speed relationship table based on the current vehicle gear position.

[0037] Fuzzy PID control is performed based on the target speed output value and the actual speed, and the fuzzy PID output value is output.

[0038] S6: Determine the control current variation range of the flow control hydraulic valve of the current working machine based on the speed difference and the gear range, specifically including: If the gear range is a low speed gear and the speed difference is greater than the third threshold, then the control current variation range of the flow control hydraulic valve of the current working machine is determined to be the first preset range. If the gear range is a low speed gear, and the speed difference is greater than the fourth threshold and less than or equal to the third threshold, then the control current variation range of the flow control hydraulic valve of the current working machine is determined to be the second preset range. If the gear range is a low speed gear, and the speed difference is greater than the second threshold and less than or equal to the fourth threshold, then the control current variation range of the flow control hydraulic valve of the current working machine is determined to be the third preset range. If the gear range is a high-speed gear and the speed difference is greater than the third threshold, then the control current variation range of the flow control hydraulic valve of the current working machine is determined to be the fourth preset range. If the gear range is a high-speed gear, and the speed difference is greater than the fourth threshold and less than or equal to the third threshold, then the control current variation range of the flow control hydraulic valve of the current working machine is determined to be the fifth preset range. If the gear range is a high-speed gear, and the speed difference is greater than the second threshold and less than or equal to the fourth threshold, then the control current variation range of the flow control hydraulic valve of the current working machine is determined to be the third preset range.

[0039] In one feasible embodiment, the first preset range, second preset range, third preset range, fourth preset range, and fifth preset range are obtained based on on-site debugging or empirical values. The third threshold and fourth threshold are set according to the speed drop situation.

[0040] S7: Determine the control current value of the flow control hydraulic valve based on the fuzzy PID output value and the control current variation range.

[0041] In some feasible embodiments, determining the control current value of the flow control hydraulic valve based on the fuzzy PID output value and the control current variation range includes: Obtain the adjustment range of the fuzzy PID control, where the upper limit of the adjustment range of the fuzzy PID is the target output speed value of the fuzzy PID control at the corresponding gear, and the lower limit is the target output speed value of the fuzzy PID control minus a certain value.

[0042] Calculate the first difference between the fuzzy PID output value and the lower limit of the adjustment range, and the second difference between the upper limit and the lower limit of the adjustment range; Calculate the ratio of the first difference to the second difference; The product of the proportional value and the maximum value of the control current variation range is calculated as the control current value.

[0043] Assuming the fuzzy PID output value is A, the adjustment range is 800-1000, and the control current variation range is 0-800, the fuzzy PID output value is converted into the control current value of the flow control hydraulic valve by the following calculation: Control current value = (A-800) / (1000-800)*800.

[0044] S8: Control the opening and closing of the flow control hydraulic valve according to the control current. The controller outputs a control current value to control the opening and closing of the flow control hydraulic valve.

[0045] Based on the above technical means, the vehicle is divided into different gear ranges. When the working machinery is in a deceleration state, different control current change ranges of the flow control hydraulic valve are set according to different deceleration conditions. Then, the control current value of the flow control hydraulic valve is calculated based on the output value of fuzzy PID control and the control current change range to control the flow control hydraulic valve. By controlling the flow control hydraulic valve to adjust the flow output, it can ensure that the actuator still receives a certain torque to achieve the desired output effect when decelerating, so that more engine power is used to maintain its own speed, thereby avoiding engine deceleration and stalling.

[0046] In some feasible embodiments, after calculating the speed difference between the vehicle's gear position speed and the actual speed, the method further includes: The control current loading curve of the flow control hydraulic valve is determined based on the speed difference. For example, when the speed difference is greater than a third threshold, the control current loading curve is the first curve; when the speed difference is greater than a fourth threshold and less than or equal to the third threshold, the control current loading curve is the second curve; and when the speed difference is greater than the second threshold and less than or equal to the fourth threshold, the control current loading curve is the third curve. The slope of the first curve is greater than the slope of the second curve, and the slope of the second curve is greater than the slope of the third curve.

[0047] After determining the control current value of the flow-controlled hydraulic valve, the valve is opened and closed according to the control current and the current loading curve. Setting the current loading curve allows adjustment of the flow-controlled hydraulic valve's operating rate, protecting hydraulic components; a slight speed drop results in a gradual current loading, while a more severe speed drop results in a faster current loading.

[0048] A second aspect of this application provides a control device for preventing speed drop and engine stall of operating machinery, the device comprising: The data acquisition unit is used to acquire the vehicle's gear position, the vehicle's gear speed, and the actual speed. The gear analysis unit is used to determine the gear range to which the vehicle belongs; The first calculation unit is used to calculate the speed difference between the vehicle's gear speed and the actual speed. The speed drop analysis unit is used to determine whether the current operating machinery is in a speed drop state based on the speed difference value. The fuzzy PID unit is used to determine the fuzzy PID output value based on the current gear and actual speed of the vehicle when the current working machinery is in a deceleration state. The current parameter determination unit allows the user to determine the range of control current variation of the flow control hydraulic valve of the current working machine based on the speed difference and the gear range. A current determination unit is used to determine the control current value of the flow control hydraulic valve based on the fuzzy PID output value and the control current variation range. An execution unit is used to control the opening and closing of the flow control hydraulic valve according to the control current.

[0049] In some feasible embodiments, the gear position analysis unit is specifically used for: Compare the vehicle's gear speed with a preset speed threshold. If the vehicle's gear speed is less than or equal to the preset speed threshold, the vehicle is in a low gear; otherwise, the vehicle is in a high gear. Alternatively, compare the actual gear position corresponding to the gear adjustment device with the preset gear position. If the actual gear position is less than or equal to the preset gear position, the vehicle is in a low gear position; otherwise, the vehicle is in a high gear position.

[0050] In some feasible embodiments, the fuzzy PID unit is specifically used for: Obtain the speed-gear relationship table for fuzzy PID control; The target speed output of the fuzzy PID control is obtained by looking up the gear-speed relationship table based on the current gear position of the vehicle. Fuzzy PID control is performed based on the target speed output value and the actual speed, and the fuzzy PID output value is output.

[0051] In some feasible embodiments, the current determination unit is specifically used for: Obtain the adjustment range of fuzzy PID control; Calculate the first difference between the fuzzy PID output value and the lower limit of the adjustment range, and the second difference between the upper limit and the lower limit of the adjustment range; Calculate the ratio of the first difference to the second difference; The product of the proportional value and the maximum value of the control current variation range is calculated as the control current value.

[0052] In some feasible embodiments, the current parameter determination unit is specifically used for: If the gear range is a low speed gear and the speed difference is greater than the third threshold, then the control current variation range of the flow control hydraulic valve of the current working machine is determined to be the first preset range. If the gear range is a low speed gear, and the speed difference is greater than the fourth threshold and less than or equal to the third threshold, then the control current variation range of the flow control hydraulic valve of the current working machine is determined to be the second preset range. If the gear range is a low speed gear, and the speed difference is greater than the second threshold and less than or equal to the fourth threshold, then the control current variation range of the flow control hydraulic valve of the current working machine is determined to be the third preset range. If the gear range is a high-speed gear and the speed difference is greater than the third threshold, then the control current variation range of the flow control hydraulic valve of the current working machine is determined to be the fourth preset range. If the gear range is a high-speed gear, and the speed difference is greater than the fourth threshold and less than or equal to the third threshold, then the control current variation range of the flow control hydraulic valve of the current working machine is determined to be the fifth preset range. If the gear range is a high-speed gear, and the speed difference is greater than the second threshold and less than or equal to the fourth threshold, then the control current variation range of the flow control hydraulic valve of the current working machine is determined to be the third preset range.

[0053] In some feasible embodiments, the current parameter determining unit is further configured to: determine the control current loading curve of the flow control hydraulic valve based on the speed difference; The execution unit is also used to control the opening and closing of the flow control hydraulic valve according to the control current and the current loading curve.

[0054] In some feasible embodiments, the speed drop analysis unit is specifically used to: compare the speed difference with a second threshold; if the speed difference is greater than the second threshold, then determine that the current working machinery is in a speed drop state.

[0055] The third aspect of this application provides a control system for preventing speed drop and engine stalling in operating machinery, such as... Figure 2 As shown, the system includes: a gear shifting device, a controller, a speed sensor, a walking device, an engine, a gear pump, actuators, and an electronically controlled multi-way valve. The gear shifting device is connected to the engine via a CAN bus. The engine drives the gear pump, which transmits energy to the walking device and actuators via a hydraulic circuit and the electronically controlled multi-way valve to drive the walking device and actuators. The speed sensor is electrically connected to the controller along with the gear shifting device. The system also includes a flow control hydraulic valve, which is installed in the hydraulic circuit between the gear pump and the electronically controlled multi-way valve. The control terminal of the flow control hydraulic valve is connected to the controller via a CAN bus. The controller is also used to: acquire the vehicle's gear position, the vehicle's gear speed, and the actual speed; determine the gear range to which the vehicle belongs; calculate the speed difference between the vehicle's gear speed and the actual speed; determine whether the current working machinery is in a deceleration state based on the speed difference; when the current working machinery is in a deceleration state, determine the fuzzy PID output value based on the current vehicle gear position and the actual speed; determine the control current variation range of the flow control hydraulic valve of the current working machinery based on the speed difference and the gear range; determine the control current value of the flow control hydraulic valve based on the fuzzy PID output value and the control current variation range; and control the opening and closing of the flow control hydraulic valve based on the control current.

[0056] Based on the aforementioned technical means, a flow control hydraulic valve is added to the control system. The controller uses a control method that divides the entire vehicle into different gear ranges. When the working machinery is in a deceleration state, different control current variation ranges for the flow control hydraulic valve are set according to different deceleration conditions. Then, based on the output value of fuzzy PID control and the control current variation range, the control current value of the flow control hydraulic valve is calculated to control the flow control hydraulic valve. By controlling the flow control hydraulic valve to adjust the flow output, it is possible to ensure that the actuator still receives a certain torque to achieve the desired output effect when decelerating, so that more engine power is used to maintain its own speed, thereby avoiding engine deceleration and stalling.

[0057] like Figure 2 As shown, in some feasible embodiments, the gear adjustment device can be a display or a gear knob, the gear adjustment device is connected to the controller via a CAN bus, and the actuator can be a boom, bucket, or attachment.

[0058] In some other feasible embodiments, instead of adding a flow control hydraulic valve, the gear pump can be adjusted to a variable pump, and the pump flow can be adjusted based on the same method described above to achieve anti-speed drop and anti-stalling.

[0059] based on Figure 2The control system for preventing speed drop and engine stall of the operating machinery shown in the image operates as follows: When the user selects a low speed gear via the display / gear knob, the control logic is as follows: Figure 3 As shown, that is: The display / gear knob sends the speed command to the engine via the CAN bus. If the vehicle's gear speed is less than or equal to threshold 1, the vehicle is determined to be in low gear, where threshold 1 is equal to the preset speed threshold.

[0060] The engine drives the gear pump, which transmits energy to the traveling device and actuators through the flow control valve and the electronically controlled multi-way valve, thereby driving the entire machine to travel and the attachments to work. When the error between the vehicle's gear speed and the actual speed is greater than threshold 2, the skid steer loader is in a speed-reducing state. The target speed value of the fuzzy PID control is obtained by looking up the table according to the current gear. Threshold 2 is equal to the second threshold.

[0061] Fuzzy PID control is achieved by using the target speed output value and the actual speed.

[0062] Based on the different speed drop ranges of the vehicle, the situation is divided into three intervals (speed drop greater than threshold 3, speed drop less than or equal to threshold 3 but greater than threshold 4, and speed drop less than or equal to threshold 4). According to different speed drop conditions, the control current of the flow control hydraulic valve is set to different variation ranges (0-parameter 1, 0-parameter 2, 0-parameter 3) to ensure that the vehicle has sufficient output torque under slight speed drop conditions. Under severe speed drop conditions, the vehicle will not stall. In this case, threshold 3 equals the third threshold, threshold 4 equals the fourth threshold, 0-parameter 1 is the first preset range, 0-parameter 2 is the second preset range, and 0-parameter 3 is the third preset range.

[0063] The fuzzy PID output value is used to calculate the corresponding current value of the flow control hydraulic valve. Different current loading curves are set according to different speed drop conditions to protect hydraulic components (slight speed drop, gentle current loading; more severe speed drop, faster current loading).

[0064] When the user selects a high gear via the display / gear selector knob, the vehicle requires greater torque output. Compared to a low gear, under the same speed drop, only a smaller reduction in the flow rate of the power pump is needed to bring the engine load back to its rated power range. The high gear control logic is as follows: Figure 3 As shown: The display / gear knob sends the speed command to the engine via the CAN bus. If the vehicle's gear speed is greater than the threshold 1, the vehicle is determined to be in high gear. The threshold 1 is equal to the preset speed threshold.

[0065] The engine drives the gear pump, which transmits energy to the traveling device and actuators through the flow control valve and the electronically controlled multi-way valve, thereby driving the skid steer loader to travel and the attachments to work. When the error between the vehicle's gear speed and the actual speed is greater than threshold 2, the skid steer loader is in a speed-reducing state. The target speed value of the fuzzy PID control is obtained by looking up the table according to the current gear. Threshold 2 is equal to the second threshold.

[0066] Fuzzy PID control is achieved by using the target speed output value and the actual speed.

[0067] Based on the varying speed drop range of the vehicle, the situation is divided into three intervals (speed drop greater than threshold 3, speed drop less than threshold 3, speed drop greater than threshold 4, and speed drop less than threshold 4). Depending on the different speed drop conditions, the control current of the flow control hydraulic valve is set to different ranges (0-parameter 4, 0-parameter 5, 0-parameter 3) to ensure sufficient output torque for the vehicle under slight speed drop conditions. Under severe speed drop conditions, the vehicle will not stall. Specifically, threshold 3 equals the third threshold, threshold 4 equals the fourth threshold, 0-parameter 4 is the fourth preset range, 0-parameter 5 is the fifth preset range, and 0-parameter 3 is the third preset range.

[0068] The fuzzy PID output value is used to calculate the corresponding current value of the flow control hydraulic valve. Different current loading curves are set according to different speed drop conditions to protect hydraulic components (slight speed drop, gentle current loading; more severe speed drop, faster current loading).

[0069] The above design ensures that when a skid steer loader is operated and subjected to drastic and frequent changes in load conditions, the gear will not be downshifted. Under heavy loads, if the engine speed decreases by more than a certain threshold, it will not stall.

[0070] 2. By dividing the gears into high and low gears and implementing segmented speed reduction control, the pump flow rate is adaptively reduced when excessive engine load is detected. Different flow control currents are set according to different speed reduction conditions. This ensures that a certain amount of torque output is maintained even during speed reduction, controlling the actuators to achieve the desired output effect.

[0071] A fourth aspect of this application provides a work machine that utilizes the aforementioned control method for preventing speed drop and engine stall. In one specific embodiment, the work machine can be a skid steer loader.

[0072] The fifth aspect of this application provides a machine-readable storage medium storing instructions for causing a machine to perform the aforementioned control method for preventing machine speed drop and engine stall.

[0073] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0074] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0075] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0076] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0077] In a typical configuration, a computing device includes one or more processors (CPU), input / output interfaces, network interfaces, and memory.

[0078] Memory may include non-persistent memory in computer-readable media, such as random access memory (RAM) and / or non-volatile memory, such as read-only memory (ROM) or flash RAM. Memory is an example of computer-readable media.

[0079] Computer-readable media includes both permanent and non-permanent, removable and non-removable media that can store information using any method or technology. Information can be computer-readable instructions, data structures, modules of programs, or other data. Examples of computer storage media include, but are not limited to, phase-change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technologies, CD-ROM, digital versatile optical disc (DVD) or other optical storage, magnetic tape, disk storage or other magnetic storage devices, or any other non-transferable medium that can be used to store information accessible by a computing device. As defined herein, computer-readable media does not include transient computer-readable media, such as modulated data signals and carrier waves.

[0080] It should also be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0081] The above are merely embodiments of this application and are not intended to limit the scope of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of the claims of this application.

Claims

1. A control method for preventing speed drop and engine stalling in operating machinery, characterized in that, The method includes: Obtain the vehicle's gear position, gear speed, and actual speed; Determine the gear range to which the vehicle belongs; Calculate the speed difference between the vehicle's gear position speed and the actual speed; Determine whether the current operating machinery is in a state of slowdown based on the speed difference value; When the current working machinery is in a deceleration state, the fuzzy PID output value is determined based on the current gear position and actual speed of the vehicle. The control current variation range of the flow control hydraulic valve of the current working machine is determined based on the speed difference and the gear range. The flow control hydraulic valve is installed on the hydraulic circuit between the gear pump and the electronically controlled multi-way valve. The gear pump transmits energy to the traveling device and the actuator through the hydraulic circuit and the electronically controlled multi-way valve. The control current value of the flow control hydraulic valve is determined based on the fuzzy PID output value and the control current variation range. The flow output is adjusted by controlling the flow control hydraulic valve according to the control current value. Determining the control current value of the flow control hydraulic valve based on the fuzzy PID output value and the control current variation range includes: Obtain the adjustment range of fuzzy PID control; Calculate the first difference between the fuzzy PID output value and the lower limit of the adjustment range, and the second difference between the upper limit and the lower limit of the adjustment range; Calculate the ratio of the first difference to the second difference; The product of the proportional value and the maximum value of the control current variation range is calculated as the control current value.

2. The control method for preventing speed drop and engine stall of operating machinery according to claim 1, characterized in that, The control current variation range of the flow control hydraulic valve of the current working machine is determined based on the speed difference and the gear range, including: If the gear range is a low speed gear and the speed difference is greater than the third threshold, then the control current variation range of the flow control hydraulic valve of the current working machine is determined to be the first preset range. If the gear range is a low speed gear, and the speed difference is greater than the fourth threshold and less than or equal to the third threshold, then the control current variation range of the flow control hydraulic valve of the current working machine is determined to be the second preset range. If the gear range is a low speed gear, and the speed difference is greater than the second threshold and less than or equal to the fourth threshold, then the control current variation range of the flow control hydraulic valve of the current working machine is determined to be the third preset range. If the gear range is a high-speed gear and the speed difference is greater than the third threshold, then the control current variation range of the flow control hydraulic valve of the current working machine is determined to be the fourth preset range. If the gear range is a high-speed gear, and the speed difference is greater than the fourth threshold and less than or equal to the third threshold, then the control current variation range of the flow control hydraulic valve of the current working machine is determined to be the fifth preset range. If the gear range is a high-speed gear, and the speed difference is greater than the second threshold and less than or equal to the fourth threshold, then the control current variation range of the flow control hydraulic valve of the current working machine is determined to be the third preset range.

3. The control method for preventing speed drop and engine stall of operating machinery according to claim 1, characterized in that, Determining whether the current operating machinery is in a speed-reducing state based on the aforementioned speed difference includes: The speed difference is compared with the second threshold. If the speed difference is greater than the second threshold, it is determined that the current working machinery is in a speed-down state.

4. The control method for preventing speed drop and engine stall of operating machinery according to claim 1, characterized in that, Determine the gear range to which the entire vehicle belongs, including: Compare the vehicle's gear speed with a preset speed threshold. If the vehicle's gear speed is less than or equal to the preset speed threshold, the vehicle is in a low gear; otherwise, the vehicle is in a high gear. Alternatively, compare the actual gear position corresponding to the gear adjustment device with the preset gear position. If the actual gear position is less than or equal to the preset gear position, the vehicle is in a low gear position; otherwise, the vehicle is in a high gear position.

5. The control method for preventing speed drop and engine stall of operating machinery according to claim 1, characterized in that, Based on the current vehicle gear and actual engine speed, determine the fuzzy PID output value, including: Obtain the speed-gear relationship table for fuzzy PID control; The target speed output of the fuzzy PID control is obtained by looking up the gear-speed relationship table based on the current gear position of the vehicle. Fuzzy PID control is performed based on the target speed output value and the actual speed, and the fuzzy PID output value is output.

6. The control method for preventing speed drop and engine stall of operating machinery according to claim 1, characterized in that, After calculating the speed difference between the vehicle's gear position speed and the actual speed, the method further includes: The control current loading curve of the flow control hydraulic valve is determined based on the speed difference. After determining the control current value of the flow control hydraulic valve, the flow control hydraulic valve is controlled according to the control current value and the current loading curve to adjust the flow output.

7. A control device for preventing speed drop and engine stalling in operating machinery, characterized in that, The device includes: The data acquisition unit is used to acquire the vehicle's gear position, the vehicle's gear speed, and the actual speed. The gear analysis unit is used to determine the gear range to which the vehicle belongs; The first calculation unit is used to calculate the speed difference between the vehicle's gear speed and the actual speed. The speed drop analysis unit is used to determine whether the current operating machinery is in a speed drop state based on the speed difference value. The fuzzy PID unit is used to determine the fuzzy PID output value based on the current gear and actual speed of the vehicle when the current working machinery is in a deceleration state. The current parameter determination unit allows the user to determine the control current variation range of the flow control hydraulic valve of the current working machine based on the speed difference and the gear range. The flow control hydraulic valve is installed on the hydraulic circuit between the gear pump and the electronically controlled multi-way valve. The gear pump transmits energy to the walking device and the actuator through the hydraulic circuit and the electronically controlled multi-way valve. A current determination unit is used to determine the control current value of the flow control hydraulic valve based on the fuzzy PID output value and the control current variation range, including: Obtain the adjustment range of fuzzy PID control; Calculate the first difference between the fuzzy PID output value and the lower limit of the adjustment range, and the second difference between the upper limit and the lower limit of the adjustment range; Calculate the ratio of the first difference to the second difference; The product of the proportional value and the maximum value of the control current variation range is calculated as the control current value; An execution unit is used to control the flow control hydraulic valve according to the control current value to adjust the flow output.

8. A control system for preventing speed drop and engine stalling in operating machinery, the system comprising: The system comprises a gear shifting device, a controller, a speed sensor, a walking device, an engine, a gear pump, actuators, and an electronically controlled multi-way valve. The gear shifting device is connected to the engine via a CAN bus. The engine drives the gear pump, which transmits energy to the walking device and actuators via a hydraulic circuit and the electronically controlled multi-way valve to drive their movement. The speed sensor and gear shifting device are both electrically connected to the controller. The system further includes a flow control hydraulic valve, which is installed in the hydraulic circuit between the gear pump and the electronically controlled multi-way valve. The control terminal of the flow control hydraulic valve is connected to the controller. The controller is further configured to: acquire the vehicle's gear position, the vehicle's gear speed, and the actual speed; determine the gear range to which the vehicle belongs; calculate the speed difference between the vehicle's gear speed and the actual speed; determine whether the current working machinery is in a deceleration state based on the speed difference; when the current working machinery is in a deceleration state, determine a fuzzy PID output value based on the current vehicle gear position and the actual speed; determine the control current variation range of the flow control hydraulic valve of the current working machinery based on the speed difference and the gear range; determine the control current value of the flow control hydraulic valve based on the fuzzy PID output value and the control current variation range; and control the flow control hydraulic valve to adjust the flow output based on the control current value; wherein determining the control current value of the flow control hydraulic valve based on the fuzzy PID output value and the control current variation range includes: Obtain the adjustment range of fuzzy PID control; Calculate the first difference between the fuzzy PID output value and the lower limit of the adjustment range, and the second difference between the upper limit and the lower limit of the adjustment range; Calculate the ratio of the first difference to the second difference; The product of the proportional value and the maximum value of the control current variation range is calculated as the control current value.

9. A type of operating machinery, characterized in that, The operating machinery is controlled by the method for preventing speed drop and engine stalling as described in any one of claims 1-6.

10. A machine-readable storage medium, characterized in that, The machine-readable storage medium stores instructions for causing the machine to perform the control method for preventing speed drop and engine stall of the operating machinery as described in any one of claims 1 to 6.

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