CN102182724A - Power matching control method and system for mobile operating machinery - Google Patents

Abstract

The invention relates to a power matching control method and a power matching control system for a mobile working machine. The power distribution control system also comprises a sensor for acquiring the flow of the working hydraulic system and the walking hydraulic system, a pressure sensor for measuring the pressure of the working hydraulic system and the walking hydraulic system, a rotating speed sensor for measuring the rotating speed of the engine, a controller for receiving signals of the sensors and a control unit for controlling the two hydraulic systems. The controller calculates the power of the two hydraulic systems and the maximum theoretical output power of the engine at the current rotating speed. When the sum of the powers of the two hydraulic systems reaches the maximum theoretical output power of the engine, the controller reasonably distributes the power of the engine according to the actual working condition, and the power matching control system not only ensures the reasonable distribution of the powers of the two hydraulic systems, but also prevents the engine from stalling due to overload.

Description

Power matching control method and system for mobile operating machinery

technical field

The invention relates to a mobile operating machine control method and system, in particular to a power matching control method and system for a working hydraulic system and a traveling hydraulic system of a mobile operating machine.

Background technique

Traditional mobile working machinery includes two important systems, the working hydraulic system and the traveling hydraulic system, which are generally driven by engines. The power of the hydraulic system is equal to the product of the pressure of the system and the flow rate of the hydraulic oil in the system, while the pressure of the hydraulic system is determined by the load, and the flow rate of the hydraulic oil is equal to the product of the displacement and the rotational speed of the hydraulic pump, so the control hydraulic system mainly It is the control of the displacement and speed of the hydraulic pump. The output power of the engine is equal to the product of the rotational speed and the torque. The rotational speed of the engine is fixed at a certain throttle opening, but the output torque is determined by the load, so the output power of the engine is determined by the load, but the output power at this time It will not exceed the maximum theoretical output power of the engine at this throttle opening.

When the mobile operating machinery is operating, the focus of equipment power distribution is different due to the different working conditions of the operation. Therefore, when the sum of the power of the working hydraulic system and the walking hydraulic system reaches the maximum theoretical output power of the engine, the power distribution of the two systems will be redistributed according to different working conditions. If the distribution is unreasonable, it will easily cause the engine to stall.

The energy saving of engineering equipment has always been the goal pursued by engineering equipment enterprises, and a large part of the power loss of engineering equipment lies in the loss of the hydraulic system. The traditional hydraulic system uses a quantitative pump to supply oil to each hydraulic component. For different working conditions, the required hydraulic oil flow rate is also different. The usual practice is to let the excess hydraulic oil flow back to the hydraulic oil tank through the overflow valve, resulting in redundant of the hydraulic energy is lost in the overflow process.

Contents of the invention

Purpose of the invention: The purpose of the present invention is to provide a power matching control method for the working hydraulic system and the walking hydraulic system of a mobile working machine; another purpose of the present invention is to provide a power matching control method using the mobile working machine According to the control system, the system and method can reasonably allocate the power of the two systems according to the different working conditions of the equipment, prevent the engine from stalling, improve the use efficiency of the engine power, and produce a better energy-saving effect.

Technical solution: The method of the present invention includes the following steps: a power distribution control method of a mobile operation machine, which is used for distribution control of the power of the engine system by the traveling hydraulic system and the working hydraulic system of the mobile operation machine,

The first step is to obtain the power of the walking hydraulic system, the power of the working hydraulic system, and the maximum theoretical output power of the engine at the current throttle opening;

The second step is to compare the sum of the power of the walking hydraulic system and the power of the working hydraulic system with the maximum theoretical output power of the engine. The maximum theoretical output power of the engine is the actual output part of the theoretical power of the engine, that is, the power obtained by the two hydraulic systems ;

If the sum of the power of the traveling hydraulic system and the working hydraulic system is less than the maximum theoretical power of the engine system, the two hydraulic systems distribute the output power of the engine system according to their respective working conditions, and the two hydraulic systems do not interfere with each other; if the traveling hydraulic system and the working hydraulic system When the sum of the power of the hydraulic system is equal to the maximum theoretical power of the engine system, the power distribution ratio of the walking hydraulic system and the working hydraulic system is adjusted according to the actual working conditions of the mobile operating machine, and the distribution ratio changes accordingly when the working conditions change. For example: the loader gets more power from the working hydraulic system during shoveling, and more power from the walking hydraulic system during transportation.

Through the above power matching control method, the output power of the engine is reasonably distributed according to different working conditions, and the engine flameout due to overload is prevented, and the use efficiency of the engine power is improved.

In order to further realize the effect of energy saving, the present invention can adopt the method of full power load sensitive control for the working hydraulic system and the traveling hydraulic system, and supply oil to each hydraulic element according to the requirement of the load.

Technical solution: The system adopting the power matching control method of the above-mentioned mobile working machine in the present invention: the power distribution control system of the mobile working machine, including a traveling hydraulic system, a working hydraulic system and an engine system; the traveling hydraulic system includes a traveling pump; the working hydraulic system includes Working pump; the walking pump and working pump are connected with the engine system. The control system also includes a first pressure sensor for measuring the pressure of the working hydraulic system, a second pressure sensor for measuring the pressure of the traveling hydraulic system, a speed sensor for measuring the engine speed, a first sensor for obtaining the flow rate of the working hydraulic system, and a sensor for obtaining the flow rate of the traveling hydraulic system The second sensor, the controller for receiving the signals of the various sensors, the walking pump control unit for controlling the walking pump, and the working pump control unit for controlling the working pump; the walking pump control unit and the working pump control unit are connected to the controller.

The pressure of the working hydraulic system is detected by the first pressure sensor; the pressure of the walking hydraulic system is detected by the second pressure sensor; the flow rate of the working hydraulic system is detected by the first sensor; the flow rate of the walking hydraulic system is detected by the second sensor; The controller calculates the power of the working hydraulic system and the walking hydraulic system according to the obtained flow and pressure; the engine speed is detected by the speed sensor, and the controller calculates the engine speed according to the preset engine power characteristics and engine efficiency coefficient and other parameters. The maximum theoretical output power of the current speed.

The controller calculates the sum of the power of the working hydraulic system and the walking hydraulic system to obtain the actual output power of the engine system; when the actual output power of the engine system reaches the maximum theoretical output power of the engine, the controller judges the At present, the working condition of the mobile working machine, for example, when the power of the working hydraulic system is greater than the power of the traveling hydraulic system, it means that the equipment is in the working mode; otherwise, it means that the equipment is in the walking mode. The controller transmits the preset power distribution ratio signals of various operation modes to the walking pump control unit and the working pump control unit respectively. The displacement of the working pump and the walking pump is adjusted through the above two control units. When the working mode changes, the controller re-sends the control signal to readjust the power distribution of the two hydraulic systems. Through the above-mentioned power matching control system, the engine output power is reasonably distributed according to different working conditions and prevents the engine from being damaged due to overload. The flameout improves the efficiency of the use of engine power.

If the sum of the power of the walking hydraulic system and the working hydraulic system is less than the maximum theoretical output power of the engine system, the two hydraulic systems will distribute the output power of the engine according to their respective working conditions.

If the sum of the power of the two hydraulic systems reaches the maximum theoretical output power of the engine system and the load is still increasing, the two hydraulic systems simultaneously reduce the displacement of the pumps according to the power distribution ratio set by the control to meet the power distribution ratio.

In order to achieve energy-saving effects, the working pump of the working hydraulic system adopts a variable pump, and the working hydraulic system controls the opening of the working pump according to the load of the actuator through a load-sensitive valve. The load-sensitive valve can automatically adjust the work according to the change of the load. The amount of oil supplied by the pump to the hydraulic components realizes the on-demand supply of oil to the hydraulic components.

Description of drawings

Fig. 1 is a schematic diagram of the first embodiment of the present invention; Fig. 2 is a schematic diagram of the second embodiment of the present invention.

Detailed ways

The present invention will be further described below in conjunction with accompanying drawing.

Embodiment 1: As shown in Figure 1, the power distribution control system of a mobile working machine includes a traveling hydraulic system 1, a working hydraulic system 2 and an engine system 3, the traveling hydraulic system 1 includes a traveling pump 11, and the working hydraulic system 2 includes a working pump 21 , the travel pump 11 and the working pump 21 are connected to the engine system 3 , therefore, the travel pump 11 and the working pump 21 are linked with the engine system 3 . The power distribution control system also includes pressure sensors 5, 12 for measuring the pressure of the working hydraulic system 2 and the traveling hydraulic system 1, a speed sensor 7 for measuring the engine speed, detecting the working pump 21 of the working hydraulic system 2 and the traveling pump 11 of the traveling hydraulic system 1 Displacement sensors 23, 14 of the displacement, a controller 4 that receives the signals of the displacement sensors 23, 14, pressure sensors 5, 12 and the rotational speed sensor 7, and a working pump control unit 9 that controls the displacement of the working pump 21 and the travel pump 11 and Travel pump control unit 8. The working pump control unit 9 is composed of a working pump controller and a working pump control oil cylinder, and the travel pump control unit 8 is composed of a travel pump controller and a travel pump control cylinder. The displacement sensors 23, 14 are opened by the swash plate of the measuring pump Calculate the displacement of the pump according to the degree or the expansion and contraction of the control cylinder.

The pressures of the working hydraulic system 2 and the traveling hydraulic system 1 are respectively detected by the pressure sensors 5 and 12, the displacements of the working pump 21 and the traveling pump 11 are respectively detected by the displacement sensors 23 and 14, and the engine speed is detected by the rotational speed sensor 7, The controller 4 calculates the power of the working hydraulic system 2 and the walking hydraulic system 1 respectively according to the measured displacement value, pressure value and rotational speed value; Calculate the maximum theoretical output power of the engine at the current speed.

The sum of the power of the working hydraulic system 2 and the walking hydraulic system 1 is the actual output power of the engine system 3; when the actual output power of the engine system 3 reaches the maximum theoretical output power of the engine system 3, the controller 4 The power of system 1 judges the current working condition of the mobile working machine. For example, when the power of working hydraulic system 2 is greater than the power of walking hydraulic system 1, it means that the equipment is in working mode; otherwise, it means that the equipment is in walking mode. The controller 4 transmits the preset power distribution ratio signals of various working modes to the walking pump control unit 8 and the working pump control unit 9 respectively. The displacements of the working pump 21 and the walking pump 11 are adjusted by the above two control units. When the operating mode changes, the controller 4 re-sends the control signal to readjust the power distribution of the two hydraulic systems. Through the above-mentioned power matching control system, the engine output power is reasonably allocated according to different working conditions and prevents the engine from being overloaded. The flameout improves the efficiency of the engine power.

When the actual output power of the engine system 3 does not reach the maximum theoretical output power of the engine, the working hydraulic system 2 and the travel hydraulic system 1 distribute the actual output power of the engine system (3) according to their respective working conditions.

In order to achieve energy-saving effects, the working pump 21 of the working hydraulic system 2 adopts a variable pump, and the working hydraulic system 2 controls the opening of the working pump 21 according to the load of the actuator 23 through the load sensing valve 22. The load sensing valve 22 can According to the change of the load, the oil supply amount of the working pump 21 to the hydraulic components is automatically adjusted, so as to realize the supply of oil to the hydraulic components on demand.

Embodiment 2: As shown in Figure 2, the power distribution control system of the mobile working machine includes a traveling hydraulic system 1, a working hydraulic system 2 and an engine system 3, the traveling hydraulic system 1 includes a traveling pump 11, and the working hydraulic system 2 includes a working pump 21 , the travel pump 11 and the working pump 21 are connected to the engine system 3 , therefore, the travel pump 11 and the working pump 21 are linked with the engine system 3 . The power distribution control system also includes flow sensors 6 and 13 for measuring the flow of the working hydraulic system 2 and the traveling hydraulic system 1, pressure sensors 5 and 12 for measuring the pressure of the working hydraulic system 2 and the traveling hydraulic system 1, and a speed sensor for measuring the engine speed 7. The controller 4 that receives the signals of the flow sensors 6, 13, the pressure sensors 5, 12 and the speed sensor 7, and the working pump control unit 9 and the walking pump control unit 8 that control the displacement of the working pump 21 and the walking pump 11.

The flow and pressure of the working hydraulic system 2 are detected respectively by the flow sensor 6 and the pressure sensor 5, and the controller 4 calculates the power of the working hydraulic system 2 according to the detected flow and pressure; The pressure and flow of the travel hydraulic system 1, the controller 4 calculates the power of the travel hydraulic system 1 according to the detected pressure and flow; the speed sensor 7 detects the speed of the engine system 3 and feeds it back to the controller 4, and the controller 4 according to The preset engine power characteristics and engine efficiency coefficient and other parameters calculate the maximum theoretical output power of the engine at the current speed.

The sum of the power of the working hydraulic system 2 and the power of the walking hydraulic system 1 is the actual output power of the engine system 3; when the actual output power of the engine system 3 reaches the maximum theoretical output power of the engine, the controller 4 The power judges the working condition of the mobile working machine at present. The controller 4 transmits the preset power distribution ratio signals of various working modes to the walking pump control unit 8 and the working pump control unit 9 respectively. The displacements of the working pump 21 and the walking pump 11 are adjusted by the above two control units. When the operating mode changes, the controller 4 re-sends the control signal to readjust the power distribution of the two hydraulic systems. Through the above-mentioned power matching control system, the engine output power is reasonably allocated according to different working conditions and prevents the engine from being overloaded. The flameout improves the efficiency of the engine power.

When the actual output power of the engine system 3 does not reach the maximum theoretical output power of the engine, the working hydraulic system 2 and the travel hydraulic system 1 distribute the realized output power of the engine system (3) according to their respective working conditions.

In order to achieve energy-saving effects, the working pump 21 of the working hydraulic system 2 adopts a variable pump, and the working hydraulic system 2 controls the opening of the working pump 21 according to the load of the actuator 23 through the load sensing valve 22. The load sensing valve 22 can According to the change of the load, the oil supply amount of the working pump 21 to the hydraulic components is automatically adjusted, so as to realize the supply of oil to the hydraulic components on demand.

Claims (12)

1. A power matching control method for a mobile operating machine, which is used to control the power distribution of the engine system (3) by the traveling hydraulic system (1) and the working hydraulic system (2) of the mobile operating machine, characterized in that the control method includes The following steps: a. Obtain the power of the walking hydraulic system (1), the power of the working hydraulic system (2), and the maximum theoretical output power of the engine at the current throttle opening; b. Compare the sum of the power of the walking hydraulic system (1) and the power of the working hydraulic system (2) with the maximum theoretical output power of the engine; If the sum of the power of the walking hydraulic system (1) and the working hydraulic system (2) is less than the maximum theoretical output power of the engine system (3), the two hydraulic systems distribute the output power of the engine system (3) according to their respective working conditions; If the sum of the power of the traveling hydraulic system (1) and the working hydraulic system (2) is equal to the maximum theoretical output power of the engine system (3), the power of the working hydraulic system (2) and the traveling hydraulic system (1) is proportionally distributed to the engine system (3) The maximum theoretical output power. 2. The power matching control method of a mobile working machine according to claim 1, characterized in that, the step of obtaining the power of the working hydraulic system (2) is through the first pressure sensor (5) and the first flow sensor ( 6) The pressure and flow of the working hydraulic system (2) are respectively detected and fed back to the controller (4) to calculate the power of the working hydraulic system (2). 3. The power matching control method of a mobile working machine according to claim 1, characterized in that the step of obtaining the power of the working hydraulic system (2) is to detect the working hydraulic system ( 2) and feed back to the controller (4); obtain the displacement of the working pump (21) of the working hydraulic system (2); obtain the speed of the working pump (21); the controller (4) according to the pressure value, displacement The power of the working hydraulic system (2) is calculated from the magnitude and speed values. 4. The power matching control method of a mobile working machine according to claim 1, characterized in that the step of obtaining the power of the traveling hydraulic system (1) is through the second pressure sensor (12) and the second flow sensor (13) respectively The pressure and flow of the traveling hydraulic system (1) are detected and fed back to the controller (4) to calculate the power of the traveling hydraulic system (2). 5. The power matching control method of a mobile working machine according to claim 1, characterized in that the step of obtaining the power of the traveling hydraulic system (1) is obtaining the displacement of the traveling pump (11) of the traveling hydraulic system (1); The rotational speed of the engine system (3) and the pressure of the travel hydraulic system (1) are respectively detected by the rotational speed sensor (7) and the second pressure sensor (12) and fed back to the controller (4); the controller (4) The power of the mobile hydraulic system (1) is calculated from the magnitude, speed and pressure values. 6. The power matching control method of a mobile working machine according to claim 1, characterized in that the step of obtaining the maximum theoretical power output by the engine at the current throttle opening is to detect the engine speed through the speed sensor (7) and feed it back to The controller (4), the controller (4) calculates the maximum theoretical output power of the engine. 7. The power matching control method of the mobile working machine according to claim 1, characterized in that the controller (4) adjusts the traveling hydraulic system (1) and the working hydraulic system according to the actual working conditions of the mobile working machine (2) The power distribution ratio. 8. The power matching control method of a mobile working machine according to any one of claims 1-7, characterized by comprising: controlling the displacement of a working pump (21) of a working hydraulic system through a load sensing valve (22). 9. A control system using the power matching control method of a mobile working machine as claimed in claim 1, comprising a travel hydraulic system (1), a working hydraulic system (2) and an engine system (3); the travel hydraulic system (1) includes Walking pump (11); Working hydraulic system (2) comprises working pump (21); Described walking pump (11) and working pump (21) are connected with engine system (3), it is characterized in that: this control system also includes measuring The first pressure sensor (5) for the pressure of the working hydraulic system (2), the second pressure sensor (13) for measuring the pressure of the traveling hydraulic system (1), the speed sensor (7) for measuring the engine speed, and the acquisition of the working hydraulic system (2) The first sensor for the flow rate, the second sensor for obtaining the flow rate of the travel hydraulic system (1), the controller (4) for receiving the signals of the various sensors, the travel pump control unit (8) for controlling the travel pump (11) and the control work pump The working pump control unit (9) of (21); the walking pump control unit (8) and the working pump control unit (9) are connected with the controller (4). the 10. The power matching control system of a mobile working machine according to claim 9, characterized in that: the first sensor is a first flow sensor (6) for detecting the flow of the working hydraulic system (2), and the second sensor It is the second flow sensor (13) for detecting the flow of the traveling hydraulic system (1). 11. The power matching control system of a mobile working machine according to claim 9, characterized in that: the first sensor is a first displacement sensor (23) for obtaining the displacement of the working pump (21) of the working hydraulic system (2) , the second sensor is a second displacement sensor (14) for obtaining the displacement of the travel pump (11) of the travel hydraulic system (1). 12. The power matching control system of a mobile working machine according to claim 9, 10 or 11, characterized in that: the working pump (21) of the working hydraulic system (2) is a variable displacement pump; the working hydraulic system ( 2) It also includes a load sensing valve (22) that controls the working pump (21) according to the load.

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