A method and apparatus for anti-flameout control of a thermal engine process of an excavator

Abstract

The application discloses a kind of excavator hot engine process anti-flameout control method and device, it is related to anti-flameout control technical field, obtains the current environment pressure where excavator is located, if current environment pressure meets starting condition, the engine of excavator is started and engine water temperature is obtained, if water temperature meets engine hot engine condition, engine hot engine process anti-flameout control strategy is executed, to keep engine speed constant on preset speed, in the process that engine speed is at preset speed, when receiving hydraulic lock switch instruction, hydraulic system hot engine anti-flameout control strategy is executed.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of anti-flameout control, and more particularly to an anti-flameout control method and device for a hot engine process of an excavator. BACKGROUND

[0002] Under the environment of high altitude, low temperature, etc., the engine of the excavator needs to be hot. The hot engine is to raise the temperature of the hydraulic oil by operating the hydraulic system, and the oil temperature does not rise without operating the machine.

[0003] After the cold start of the engine, during the engine hot process, due to the low oxygen content on the plateau, the large viscosity of the low-temperature hydraulic oil, the large frictional resistance, and other factors, the performance deteriorates greatly, and even flameout problems may occur. Thus, the basic hot process cannot be smoothly carried out, which is not conducive to the rapid hot of the machine and the rapid use. Moreover, once the flameout occurs, the impact on the starter and the battery is great.

[0004] Therefore, how to avoid the flameout of the excavator during the hot process is a problem to be solved by the present application. SUMMARY

[0005] Therefore, the present application discloses an anti-flameout control method and device for a hot engine process of an excavator, aiming to realize the purpose that the excavator will not flameout during the hot process.

[0006] In order to achieve the above-mentioned purpose, the disclosed technical solution is as follows:

[0007] The first aspect of the present application discloses an anti-flameout control method for a hot engine process of an excavator, which comprises:

[0008] obtaining the current environmental pressure of the excavator;

[0009] if the current environmental pressure meets the starting condition, starting the engine of the excavator and obtaining the engine water temperature;

[0010] if the water temperature meets the engine hot condition, executing an engine hot process anti-flameout control strategy to keep the engine speed constant at a preset speed;

[0011] during the process that the engine speed is at the preset speed, when a hydraulic lock switch instruction is received, executing a hydraulic system hot anti-flameout control strategy.

[0012] Preferably, if the current environmental pressure meets the starting condition, starting the engine of the excavator and obtaining the engine water temperature, comprises:

[0013] comparing the current environmental pressure with a set value;

[0014] determining that the current ambient pressure meets a starting condition if the current ambient pressure is less than the set value;

[0015] starting an engine of the excavator and obtaining an engine water temperature if the current ambient pressure meets the starting condition.

[0016] Preferably, the engine warm-up process anti-stall control strategy is executed if the water temperature meets an engine warm-up condition, including:

[0017] comparing the engine water temperature with a preset water temperature;

[0018] performing engine warm-up through an engine warm-up program if the engine water temperature is less than or equal to the preset water temperature;

[0019] increasing the idle speed of the engine by a preset time interval and a preset speed increase if a speed-up instruction is invalid and a hydraulic lock switch is invalid during the engine warm-up, until a highest gear speed is reached;

[0020] determining that the engine warm-up is completed if the engine water temperature is greater than the preset water temperature during the engine idle speed reaching the highest gear speed;

[0021] maintaining the engine speed at a preset speed after the engine warm-up is completed.

[0022] Preferably, the hydraulic system warm-up anti-stall control strategy includes at least an engine power boost strategy and a hydraulic loading anti-speed drop strategy, and the hydraulic system warm-up anti-stall control strategy is executed when a hydraulic lock switch instruction is received during the engine speed being at the preset speed, including:

[0023] performing hydraulic control system warm-up through a hydraulic system warm-up program when the hydraulic lock switch instruction is received during the engine speed being at the preset speed;

[0024] the engine power boost strategy and the hydraulic loading anti-speed drop strategy are executed respectively to complete the execution of the hydraulic system warm-up anti-stall control strategy during the hydraulic control system warm-up.

[0025] Preferably, the execution of the engine power boost strategy includes:

[0026] obtaining a target torque through a feedforward torque based on a pilot pressure and a torque curve corresponding to different pilot pressure values, wherein the target torque is the maximum value of each final torque obtained under the condition of multiple pilot pressures during the operation of the excavator;

[0027] obtaining an actual speed during the operation of the excavator;

[0028] correcting the actual rotating speed by setting a rotating speed;

[0029] adjusting an engine of the excavator by the target torque and the corrected actual rotating speed to complete a process of executing a hydraulic system warm-up anti-stalling control strategy.

[0030] Preferably, the process of executing the hydraulic loading anti-speed drop strategy comprises:

[0031] obtaining a real-time intake air amount of an engine of the excavator, a real-time hydraulic oil temperature of the hydraulic system and a hydraulic loading rate of the hydraulic system;

[0032] determining an intake air amount correction parameter according to the real-time intake air amount and determining an oil temperature correction parameter according to the real-time hydraulic oil temperature;

[0033] correcting the hydraulic loading rate in real time by the intake air amount correction parameter;

[0034] correcting the hydraulic loading rate after the intake air amount correction by the oil temperature correction parameter to complete the process of the hydraulic loading anti-speed drop strategy.

[0035] Preferably, in the process of the engine rotating speed being at the preset rotating speed, when receiving a hydraulic lock switch instruction, the process of executing the hydraulic system warm-up anti-stalling control strategy further comprises:

[0036] if the water temperature of the engine is greater than a preset water temperature and the hydraulic oil temperature is greater than a preset oil temperature, executing a vehicle control program.

[0037] The second aspect of the present application discloses a device for preventing an excavator from stalling during a warm-up process, which comprises:

[0038] an obtaining unit, configured to obtain a current environmental pressure in which the excavator is located;

[0039] a starting unit, configured to start an engine of the excavator and obtain a water temperature of the engine if the current environmental pressure meets a starting condition;

[0040] a first executing unit, configured to execute an engine warm-up process anti-stalling control strategy to keep the engine rotating speed constant at a preset rotating speed if the water temperature meets an engine warm-up condition;

[0041] a second executing unit, configured to execute a hydraulic system warm-up anti-stalling control strategy when receiving a hydraulic lock switch instruction in a process of the engine rotating speed being at the preset rotating speed.

[0042] Preferably, the starting unit comprises:

[0043] a first comparing module, configured to compare the current environmental pressure with a set value;

[0044] The first determining module is configured to determine that the current ambient pressure meets a starting condition if the current ambient pressure is less than the set value.

[0045] The starting module is configured to start an engine of the excavator and acquire an engine water temperature if the current ambient pressure meets the starting condition.

[0046] Preferably, the first execution unit comprises:

[0047] The second comparing module is configured to compare the engine water temperature with a preset water temperature.

[0048] The first execution module is configured to perform an engine warm-up process through an engine warm-up program if the engine water temperature is less than or equal to the preset water temperature.

[0049] The speed increasing module is configured to increase the idle speed of the engine according to a preset time interval and a preset speed increase if it is monitored that the speed-up instruction is invalid and the hydraulic lock switch is invalid, until the highest gear speed is reached.

[0050] The second determining module is configured to determine that the engine warm-up process is completed if the engine water temperature is greater than the preset water temperature when the idle speed of the engine reaches the highest gear speed.

[0051] The constant module is configured to keep the engine speed constant at the preset speed after the engine warm-up process is completed.

[0052] According to the above technical solution, the application discloses a method and device for preventing flameout during the warm-up process of an excavator. The current ambient pressure of the excavator is acquired. If the current ambient pressure meets the starting condition, the engine of the excavator is started and the engine water temperature is acquired. If the water temperature meets the engine warm-up condition, the engine warm-up process is executed to prevent flameout, and the engine speed is kept constant at the preset speed. When the hydraulic lock switch instruction is received during the process in which the engine speed is at the preset speed, the hydraulic system warm-up process is executed to prevent flameout.

[0053] According to the above solution, in the highland, low temperature and other environments, the engine of the excavator is first warmed up. The engine warm-up process is realized through the alternately changed speed to achieve rapid warm-up. Then, the hydraulic system is warmed up to prevent the damage to the engine caused by directly operating the whole vehicle at low temperature. The hydraulic system flameout prevention strategy is realized through the collaborative control of the engine and the hydraulic system. The main power of the engine is improved through measures such as increasing the speed, increasing the oil injection and accelerating the oil injection. The maximum capacity of the engine is used as much as possible to effectively avoid the flameout caused by the sudden increase of the load during the warm-up process of the excavator. The purpose of preventing the excavator from being extinguished during the warm-up process is achieved. BRIEF DESCRIPTION OF DRAWINGS

[0054] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the accompanying drawings needed to be used in the embodiments or prior art description will be briefly introduced as follows. Obviously, the accompanying drawings in the following description only are a part of the present application, and those skilled in the art can obtain other drawings according to the provided drawings without any creative effort.

[0055] Figure 1 A flowchart of a method for preventing misfire in a warm-up process of an excavator disclosed by an embodiment of the present application;

[0056] Figure 2 An example graph of speed performance in a warm-up process disclosed by an embodiment of the present application;

[0057] Figure 3 A framework diagram of a misfire control strategy in an engine warm-up process disclosed by an embodiment of the present application;

[0058] Figure 4 A diagram of an engine power boost strategy disclosed by an embodiment of the present application;

[0059] Figure 5 A curve diagram of a hydraulic loading anti-speed drop strategy disclosed by an embodiment of the present application;

[0060] Figure 6 A flowchart of another method for preventing misfire in a warm-up process of an excavator disclosed by an embodiment of the present application;

[0061] Figure 7 A structure diagram of a device for preventing misfire in a warm-up process of an excavator disclosed by an embodiment of the present application. DETAILED DESCRIPTION

[0062] The technical solutions in the embodiments of the present application will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, but not all the embodiments. Based on the embodiments in the present application, all the other embodiments obtained by those skilled in the art without any creative effort are within the scope of protection of the present application.

[0063] In this application, the terms "comprise", "contain", or any other variant thereof, are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements not only includes those elements, but also includes other elements not explicitly listed, or further includes elements inherent to such a process, method, article or device. Without more limitations, the element defined by the statement "comprises a" does not exclude the presence of other identical elements in the process, method, article or device comprising the element.

[0064] As can be known from the background art, after the engine is cold started, during the engine warming-up process, due to factors such as low oxygen content on the plateau, high viscosity of low-temperature hydraulic oil, large frictional resistance, and the like, the performance deteriorates greatly, and even misfire problems may occur. Thus, the basic warming-up process cannot be smoothly carried out, which is not conducive to the rapid warming-up and rapid use of the machine. Moreover, once misfire occurs, the impact on the starter and the storage battery is great upon re-starting. Therefore, how to avoid the occurrence of misfire during the warming-up process of the excavator is a problem that needs to be solved urgently by the present application.

[0065] In order to solve the above problems, the present application discloses a kind of excavator warming-up process's anti-misfire control method and device, in plateau, low temperature and the like environment, first to the engine of excavator is warmed up, engine warming-up process is realized by the alternate change of speed to fast warm-up, again to hydraulic system is warmed up, prevent the damage to engine caused by engine low temperature directly operating whole vehicle. Hydraulic system anti-misfire strategy is controlled by engine and hydraulic system, by the main power of engine such as increasing speed, increasing injection, accelerating injection, as far as possible to give full play to the maximum capacity of engine, effectively avoid the situation that the load of excavator suddenly increases due to operation during the warming-up process may cause misfire, realize the purpose that excavator will not misfire during the warming-up process. Specific implementation mode is specifically explained by the following embodiment.

[0066] Reference Figure 1 As shown in the figure, the excavator warming-up process anti-misfire control method disclosed by the embodiment of the present application mainly includes the following steps:

[0067] S101: obtain the current environmental pressure of the excavator.

[0068] The current environmental pressure of the excavator can be obtained by a vehicle-mounted pressure sensor, an intake amount control module, an engine intake amount control algorithm, or the like. The way to obtain the current environmental pressure of the excavator is not limited in the present application.

[0069] S102: if the current environmental pressure meets the starting condition, start the engine of the excavator and obtain the engine water temperature.

[0070] The starting conditions are determined by the current ambient pressure and the set value.

[0071] Specifically, if the current ambient pressure meets the starting conditions, the process of starting the excavator engine and obtaining the engine water temperature is shown in A1-A3.

[0072] A1: Compare the current ambient pressure with the set value.

[0073] The setting value is set according to the actual situation and is not specifically limited in this application.

[0074] A2: If the current ambient pressure is lower than the set value, determine whether the current ambient pressure meets the start-up conditions.

[0075] A3: When the current ambient pressure meets the starting conditions, start the excavator engine and obtain the engine water temperature.

[0076] S103: If the water temperature meets the engine warm-up condition, execute the engine warm-up process anti-stall control strategy to keep the engine speed constant at a preset speed.

[0077] In S103, if the water temperature meets the engine warm-up condition, the engine warm-up process anti-stall control strategy is executed through the engine warm-up program. Among them, the engine warm-up program is used to automatically lock and prohibit speed increase and operate the hydraulic system.

[0078] The speed performance of the specific thermal engine process is as follows Figure 2 shown. Figure 2 This is just an example.

[0079] Figure 2 This figure shows the engine speed during warm-up at an altitude of 4700 meters and an ambient temperature of -20 degrees Celsius. The horizontal axis is time, and the vertical axis is speed.

[0080] In high-altitude, low-temperature environments, after a cold start, an excavator's engine undergoes a significant performance deterioration during the vehicle's warm-up process (operating the hydraulic system raises the hydraulic oil temperature, while not operating the machine causes the oil temperature to rise). This can even lead to flameouts due to factors such as the low oxygen content in the plateau, the high viscosity of the low-temperature hydraulic oil, and the high frictional resistance. This prevents the basic warm-up process from proceeding smoothly, hindering the machine's rapid warm-up and commissioning. Furthermore, once the engine stalls, restarting it incurs significant damage to the starter and battery. Therefore, this solution, specifically designed to prevent flameouts during the excavator's warm-up process in high-altitude, low-temperature environments, effectively prevents flameouts during the warm-up process due to sudden load increases caused by operations.

[0081] Specifically, if the water temperature meets the engine warming condition, an engine warming process anti-stalling control strategy is executed to keep the engine speed constant at a preset speed, as shown in B1-B5.

[0082] B1: The engine water temperature is compared with a preset water temperature.

[0083] The preset water temperature can be 40℃, 45℃, etc., and the preset water temperature is set according to actual conditions, which is not limited in the present application.

[0084] B2: If the engine water temperature is less than or equal to the preset water temperature, the engine warming is performed through an engine warming program.

[0085] Warming refers to the process of rapidly warming the engine and hydraulic system after the vehicle starts in a low-temperature environment. Generally, the driver will operate the machine to load the system to quickly warm up the machine. The operation can be slow or fast.

[0086] B3: During the engine warming process, if it is monitored that the speed-up instruction is invalid and the hydraulic lock switch is invalid, the idle speed of the engine is increased by a preset time interval and a preset speed increase until the highest gear speed is reached.

[0087] The preset time interval can be 30 seconds (s), 40 s, etc., and the preset time interval is set according to actual conditions, which is not limited in the present application.

[0088] The preset speed increase can be 100 revolutions per minute (RPM), 110 RPM, etc., and the preset speed increase is set according to actual conditions, which is not limited in the present application. The preset speed increase of the present application is preferably 100 RPM.

[0089] B4: During the process of the engine idle speed reaching the highest gear speed, if the engine water temperature is greater than the preset water temperature, it is determined that the engine warming is completed.

[0090] To facilitate understanding of the process of executing the engine warming process anti-stalling control strategy to keep the engine speed constant at a preset speed if the water temperature meets the engine warming condition, an example is provided for illustration:

[0091] For example, when the excavator starts successfully in a highland, low-temperature, or other environment, if the engine water temperature is lower than 40℃ at this time, the engine warming program is first entered, at which time the engine warming program automatically locks to prohibit speed-up and operate the hydraulic system. The engine warming program automatically runs, and the speed is increased from idle speed by 100 RPM, each speed is maintained for 30 s, until the water temperature exceeds 40℃, indicating that the engine warming is completed.

[0092] B5: After the engine warm-up is completed, the engine speed is kept constant at a preset speed.

[0093] The preset speed can be 1400 RPM, 1500 RPM, etc. The preset speed is set according to actual conditions, and the preset speed of the present application is preferably 1400 RPM. For example, after the engine warm-up is completed, the vehicle speed is automatically kept constant at 1400 RPM.

[0094] S104: During the process that the engine speed is at the preset speed, when a hydraulic lock switch instruction is received, a hydraulic system warm-up anti-flameout control strategy is executed.

[0095] In S104, during the process that the engine speed is at the preset speed, when a hydraulic lock switch instruction is received, the hydraulic control system is warmed up through the hydraulic system warm-up program. During the process of warming up the hydraulic control system, the engine power boosting strategy and the hydraulic loading anti-speed drop strategy are executed respectively to complete the process of executing the hydraulic system warm-up anti-flameout control strategy.

[0096] The hydraulic system warm-up anti-flameout control strategy at least includes the engine power boosting strategy and the hydraulic loading anti-speed drop strategy.

[0097] The process of specifically executing the engine power boosting strategy is shown in C1-C4.

[0098] C1: The target torque is obtained by a feedforward torque based on a pilot pressure and a torque curve for different pilot pressure values. The target torque is the maximum value of the final torque under the condition of multiple pilot pressures obtained during the operation of the excavator.

[0099] The different pilot pressure values include a bucket rod retraction pilot pressure value, a bucket rod swing pilot pressure value, and a boom lifting pilot pressure value.

[0100] C2: The actual speed during the operation of the excavator is obtained.

[0101] C3: The actual speed is corrected by the set speed.

[0102] The present scheme adds a load-based speed correction value (positive value) to the set speed, and the greater the load, the greater the speed correction value.

[0103] The set speed is determined by the load speed correction value, the calibration value, the total engine demand torque during the operation, and the gear speed.

[0104] C4: The engine of the excavator is adjusted by the target torque and the corrected actual speed to complete the process of executing the hydraulic system warm-up anti-flameout control strategy.

[0105] The engine power boosting strategy mainly boosts the engine speed, while increasing the fuel injection amount. The increase in fuel injection amount can be achieved by increasing the torque, shielding all fuel injection limits, such as smoke limits, and the like. Specifically, as shown in Figure 3 . Figure 3 A schematic diagram of the engine warm-up process anti-flameout control strategy is shown.

[0106] Figure 3 In the prior art, a feedforward torque based on pilot pressure is added to the traditional engine proportional and integral control (Proportional Integral) PI torque calculation. The feedforward torque is obtained by looking up a torque curve (the X-axis of the torque curve is the pilot pressure value, and the Z-axis is the torque set value) through different pilot pressure values (stick in, stick out, boom up, etc.). Since the excavator operation process involves multiple pilot pressures, the final torque is the maximum value, i.e., the target torque. Thus, in the engine control process, the actual torque is larger than the traditional torque, and more fuel is injected faster.

[0107] Figure 3 In the prior art, K p is proportional control; K i is integral control; Trq i is integral calculated torque; Trq pi is the sum of proportional calculated torque and integral calculated torque; Trq piolt is the feedforward torque value obtained by looking up the pilot pressure curve; PI calculates the torque value and adds it to obtain the control torque, which is used to eliminate the speed deviation and make the actual speed close to the set speed. On this basis, a feedforward control is introduced, which is mainly based on the operation of the excavator's pilot handle signal and is obtained by looking up the built-in torque curve. The torque value obtained in this way is greater than the traditional PI torque value. The greater the torque, the more fuel is injected. The better the responsiveness.

[0108] The working speed of the traditional excavator is the set speed, and the actual speed will be greater than or less than the set speed (such as when the speed is lower than the gear speed when loading, and the speed is higher than the gear speed when unloading) as the load changes. This scheme increases the speed correction value based on the load (which is positive) on the basis of the set speed, and the greater the load, the greater the speed correction value. Specifically, as shown in equation (1):

[0109] Set speed = gear speed + factor * (Trq 总 - Trq 起掉 ) (1)

[0110] Wherein, factor is a calibration value; Trq 总 is the total engine demand torque during operation; and Trq 起掉 is set to ensure that the set speed is equal to the gear speed when the vehicle is not in operation.

[0111] The traditional excavator operation loading process speed gradually decreases, and the present scheme can gradually increase the loading process speed, thereby further improving the engine load capacity. The traditional excavator operation loading process speed and the loading process speed of the present scheme can be referred to as shown in the following table. Figure 4 Figure 4 A schematic diagram of the engine power lifting strategy is shown.

[0112] Figure 4 In the figure, the red speed curve is the traditional excavator operation loading process speed gradually decreases. The black speed curve is the engine power lifting strategy of the present scheme. The engine power lifting strategy of the present scheme improves the engine speed and increases the engine injection torque during the operation process, thereby realizing the power lifting of the engine during the warm-up process.

[0113] After the engine warm-up is completed, if the driver receives an instruction to open the hydraulic lock switch, the system will automatically enter the hydraulic system warm-up program to warm up the hydraulic system in response to the instruction of the hydraulic lock switch. The hydraulic lock switch is an enabling switch for excavator operation. When the hydraulic lock switch is opened, the hydraulic circuit is turned on, and at this time, the machine is operated, and the working device will act according to the instruction. When the hydraulic lock switch is closed, the hydraulic circuit is cut off, and at this time, the machine is operated, and the working device has no reaction.

[0114] During the process of the working device acting according to the instruction, the hydraulic operation handle is operated, the hydraulic controller TCU sends a pressure signal (0-40 bar), and the pilot pressure drives the main valve to open and close the corresponding valve core, thereby realizing the action of the working device.

[0115] The specific process of implementing the hydraulic loading anti-speed drop strategy is shown as E1-E4.

[0116] E1: Obtain the real-time intake amount of the current engine of the excavator, the real-time hydraulic oil temperature of the hydraulic system, and the hydraulic loading rate of the hydraulic system.

[0117] The curve of the hydraulic loading rate of the hydraulic system (i.e., the hydraulic loading power curve) is determined by the engine intake amount and the correction coefficient of the gear position set power.

[0118] E2: Determine the intake amount correction parameter according to the real-time intake amount, and determine the oil temperature correction parameter according to the real-time hydraulic oil temperature.

[0119] The correction coefficient is a built-in correction coefficient according to the intake amount and the hydraulic oil temperature.

[0120] The intake amount curve is obtained according to the real-time intake amount, the K1 coefficient (i.e., the intake amount correction coefficient) is found through the intake amount curve, the oil temperature curve is obtained according to the real-time hydraulic oil temperature, and the K2 coefficient (i.e., the oil temperature correction coefficient) is found through the oil temperature curve. ​

[0121] E3: Real-time correction of the hydraulic loading rate by the intake air amount correction parameter.

[0122] E4: Oil temperature correction of the hydraulic loading rate after intake air amount correction by the oil temperature correction parameter, to complete the process of the hydraulic loading anti-stall strategy.

[0123] The correction process is to multiply the hydraulic loading rate by the K1 coefficient and the K2 coefficient. The purpose of the correction is to reduce the hydraulic loading rate.

[0124] The hydraulic loading anti-stall strategy mainly considers the current engine intake air amount and the current hydraulic oil temperature in the current loading rate of the current, and adjusts the hydraulic loading rate in real time according to the intake air amount correction parameter, and corrects the hydraulic loading rate after the intake air amount correction based on the oil temperature correction parameter.

[0125] It should be noted that the purpose of the heat engine is to quickly raise the temperature by operating the machine, so the operating performance of the machine is not high, in order to maximize the effectiveness of the hydraulic loading anti-stall strategy, and to ensure that the engine does not stall as much as possible, the above power ramp curve can be calibrated very slowly (the slower the pump end load is loaded, the slower the load is loaded, and the slower the load is loaded, the less likely it is to stall).

[0126] The hydraulic loading anti-stall strategy mainly adds a distributed mapping structure (Rmap) function to the pump power loading. The Rmap function is used to control the ramp of the pump power, and to reduce the pump power loading speed. The hydraulic loading anti-stall strategy is a pump power loading strategy based on the cycle intake air amount and the hydraulic oil temperature. The pump power loading strategy based on the cycle intake air amount and the hydraulic oil temperature is to control the pump power loading slope based on the cycle intake air amount and the hydraulic oil temperature. The lower the oil temperature, the slower the load, and the greater the slope of the ramp.

[0127] The hydraulic loading anti-stall strategy is described in detail as shown in Figure 5 . Figure 5 The curve diagram of the hydraulic loading anti-stall strategy is shown.

[0128] Figure 5 In the figure, the X-axis is the engine intake air amount, and the unit is grams per second (g / h); the Y-axis is the correction coefficient of the gear setting power.

[0129] The traditional loading of the pump is mainly that the hydraulic system controller TCU calculates the flow demand according to the operation demand (pilot signal size), combines the current pump pressure and power setting, calculates the required displacement change at this time, and then inputs the pump regulator, and the displacement of the pump is changed. The traditional consideration of action speed and the like is usually relatively fast for the displacement loading instruction (current) of the pump, and the speed drop of the plain working condition can be ensured within a certain range. However, in the highland area, the rapid current loading instruction caused by performance deterioration leads to a huge speed drop, and even stall. Therefore, the hydraulic loading anti-speed drop strategy of the present scheme is used to solve this problem.

[0130] In the process that the engine speed is at the preset speed, when receiving the hydraulic lock switch instruction, after executing the hydraulic system engine anti-stall control strategy, if it is monitored that the water temperature of the engine is greater than the preset water temperature, and the hydraulic oil temperature is greater than the preset oil temperature, the vehicle control program is executed.

[0131] For example, in the process of heating the hydraulic control system, if the water temperature exceeds 80℃ and the hydraulic oil temperature exceeds 30℃, it indicates that the vehicle heating is completed, and the heating program is exited, and the normal vehicle control program is entered. The vehicle control program is a program for operation developed by the excavator product.

[0132] In order to facilitate the understanding of the anti-stall control process of the excavator heating process, combined with Figure 6 Example is given as follows:

[0133] For example, the current environment pressure of the excavator is obtained, if the current environment pressure is less than the set value, the excavator is started, and if the starting is successful, the engine water temperature is obtained;

[0134] It is judged whether the engine water temperature is less than or equal to 40℃;

[0135] If not, the fixed speed is kept constant at the preset speed (such as 1400 RPM);

[0136] If yes, the engine heating program is executed to heat the engine;

[0137] In the process of heating the engine, if it is monitored that the speed-up instruction is invalid, and the hydraulic lock switch is invalid, that is, SpdEnc_st=0, the speed is automatically increased by 100 RPM every 30 s from the idle speed until the highest gear speed, and the engine water temperature at this time is obtained;

[0138] It is judged whether the engine water temperature is greater than 40℃, and the fixed speed is kept constant at the preset speed (such as 1400 RPM);

[0139] It is judged whether the hydraulic switch is opened;

[0140] If no, return to execute the step of keeping the constant rotating speed at the preset rotating speed (e.g. 1400 RPM);

[0141] If yes, execute the hydraulic system hot engine anti-stalling control strategy;

[0142] Judge whether the engine water temperature exceeds 80℃ and the hydraulic oil temperature is greater than 30℃;

[0143] If yes, enter the normal vehicle control program;

[0144] If no, return to execute the step of executing the hydraulic system hot engine anti-stalling control strategy.

[0145] The application can ensure that there is no risk of stalling during the hot engine process of the excavator under highland, low temperature and other conditions regardless of how the user operates the machine and what load is encountered, and can maximize the rapid and smooth completion of the hot engine process. The anti-stalling strategy (engine hot engine process anti-stalling control strategy and hydraulic system hot engine anti-stalling control strategy) of the application can maximize the maximum capacity of the engine through the cooperative control of the hydraulic system and the engine system, and can ensure that there is no risk of stalling during the hot engine process of the excavator under highland, low temperature and other conditions regardless of how the user operates the machine and what load is encountered.

[0146] The hot engine process of the application is divided into two stages, the engine is first heated, then the hydraulic system is heated, and finally the vehicle control program is executed to perform the whole vehicle operation. The damage to the engine caused by directly operating the whole vehicle at low temperature is prevented. The engine hot engine process is realized through the alternately changed rotating speed to achieve rapid heating. The hydraulic system anti-stalling strategy can maximize the maximum capacity of the engine through the cooperative control of the engine and the hydraulic system, and can ensure that there is no risk of stalling.

[0147] The application embodiment has the beneficial effects that under highland, low temperature and other conditions, the engine of the excavator is first heated, the engine hot engine process is realized through the alternately changed rotating speed to achieve rapid heating, and then the hydraulic system is heated to prevent the damage to the engine caused by directly operating the whole vehicle at low temperature. The hydraulic system anti-stalling strategy can maximize the maximum capacity of the engine through the cooperative control of the engine and the hydraulic system, and can effectively avoid the situation that the excavator is stalled due to the sudden increase of load caused by operation during the hot engine process, so as to achieve the purpose that the excavator is not stalled during the hot engine process.

[0148] Based on the above embodiment Figure 1 The application embodiment also discloses a kind of anti-stalling control device of excavator hot engine process, which is disclosed as Figure 7As shown, the anti-flameout control device of the excavator engine warming-up process comprises:

[0149] The acquisition unit 701 is configured to acquire a current ambient pressure of the excavator;

[0150] The starting unit 702 is configured to start the engine of the excavator and acquire an engine water temperature if the current ambient pressure meets a starting condition;

[0151] The first execution unit 703 is configured to execute an engine warming-up process anti-flameout control strategy to keep the engine speed constant at a preset speed if the water temperature meets an engine warming-up condition;

[0152] The second execution unit 704 is configured to execute a hydraulic system warming-up anti-flameout control strategy when receiving a hydraulic lock switch instruction during the process that the engine speed is at the preset speed.

[0153] Further, the starting unit 702 comprises:

[0154] The first comparison module is configured to compare the current ambient pressure with a set value;

[0155] The first determination module is configured to determine that the current ambient pressure meets the starting condition if the current ambient pressure is less than the set value;

[0156] The starting module is configured to start the engine of the excavator and acquire the engine water temperature if the current ambient pressure meets the starting condition.

[0157] Further, the first execution unit 703 comprises:

[0158] The second comparison module is configured to compare the engine water temperature with a preset water temperature;

[0159] The first execution module is configured to perform engine warming-up through an engine warming-up program if the engine water temperature is less than or equal to the preset water temperature;

[0160] The speed-up module is configured to increase the idle speed of the engine according to a preset time interval and a preset speed-up if it is monitored that the speed-up instruction is invalid and the hydraulic lock switch is invalid during the process of engine warming-up, until the highest gear speed is reached;

[0161] The second determination module is configured to determine that the engine warming-up is completed if the engine water temperature is greater than the preset water temperature during the process that the idle speed of the engine reaches the highest gear speed;

[0162] The constant module is configured to keep the engine speed constant at the preset speed after the engine warming-up is completed.

[0163] Further, the hydraulic system warm-up anti-stall control strategy comprises at least an engine power boost strategy and a hydraulic loading anti-speed-drop strategy, the second execution unit 704 comprises:

[0164] The second execution module is configured to, when receiving the hydraulic lock switch instruction during the process that the engine speed is at the preset speed, perform hydraulic control system warm-up through the hydraulic system warm-up program.

[0165] The third execution module is configured to, during the process of performing hydraulic control system warm-up, execute the engine power boost strategy and the hydraulic loading anti-speed-drop strategy respectively, so as to complete the process of executing the hydraulic system warm-up anti-stall control strategy.

[0166] Further, the third execution module for executing the engine power boost strategy comprises:

[0167] The first acquisition submodule is configured to obtain a target torque through a feedforward torque based on a pilot pressure and a torque curve corresponding to different pilot pressure values, wherein the target torque is the maximum value of each final torque obtained in the process of operating the excavator under the condition of multiple pilot pressures.

[0168] The second acquisition submodule is configured to obtain an actual speed in the process of operating the excavator.

[0169] The first correction submodule is configured to correct the actual speed by using the set speed.

[0170] The adjustment submodule is configured to adjust the engine of the excavator by using the target torque and the corrected actual speed, so as to complete the process of executing the hydraulic system warm-up anti-stall control strategy.

[0171] Further, the third execution module for executing the hydraulic loading anti-speed-drop strategy comprises:

[0172] The third acquisition submodule is configured to obtain a real-time intake amount of the engine of the excavator, a real-time hydraulic oil temperature of the hydraulic system, and a loading rate of the hydraulic system.

[0173] The determination submodule is configured to determine an intake amount correction parameter according to the real-time intake amount, and determine an oil temperature correction parameter according to the real-time hydraulic oil temperature.

[0174] The second correction submodule is configured to correct the loading rate of the hydraulic system in real time by using the intake amount correction parameter.

[0175] The third correction submodule is configured to correct the loading rate of the hydraulic system after the intake amount correction by using the oil temperature correction parameter, so as to complete the process of executing the hydraulic loading anti-speed-drop strategy.

[0176] Further, the anti-stall control device for the warm-up process of the excavator further comprises:

[0177] The third execution unit is configured to execute a vehicle control program if the engine water temperature is greater than a preset water temperature and the hydraulic oil temperature is greater than a preset oil temperature.

[0178] The excavator of the embodiment of the present application has the following beneficial effects: in a highland, low temperature or other environment, the engine of the excavator is first warmed up, the engine warming-up process is realized by alternating the speed, and then the hydraulic system is warmed up, so as to prevent the damage to the engine caused by directly operating the whole vehicle at low temperature. The hydraulic system anti-flameout strategy realizes the collaborative control of the engine and the hydraulic system, increases the speed, increases the fuel injection and speeds up the fuel injection, so as to maximize the power of the engine, effectively avoid the flameout caused by the sudden load increase during the operation of the excavator during the warming-up process, and realize the purpose that the excavator will not flameout during the warming-up process.

[0179] For each method embodiment described above, in order to simply describe, each method embodiment is described as a series of action combinations, but those skilled in the art should know that the present application is not limited by the action sequence described, because according to the present application, some steps can be performed in other sequences or simultaneously. Secondly, those skilled in the art should know that the embodiments described in the specification are all preferred embodiments, and the actions and modules involved are not necessarily required by the present application.

[0180] It should be noted that each embodiment in the specification is described in a progressive manner, and each embodiment focuses on the difference from other embodiments. The same and similar parts of each embodiment can be referred to each other. For system embodiments, since they are basically similar to method embodiments, the description is relatively simple, and the relevant parts can be referred to the part of the method embodiment.

[0181] The steps in the method of each embodiment of the present application can be adjusted, combined and reduced in sequence according to actual needs.

[0182] Finally, it should be noted that in this paper, relationship terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or sequence between the entities or operations.

[0183] The above description of the disclosed embodiments enables a person skilled in the art to implement or use the present application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the scope of the present application. Therefore, the present application will not be limited to the embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

[0184] The above merely preferred embodiments of the present application, it should be noted that for those of ordinary skill in the art, without departing from the principles of the present application, can also make a number of improvements and refinements, these improvements and refinements should also be considered as the scope of protection of the present application.

Claims

1. A method of anti-diesel control of a thermal engine process of an excavator, characterized in that, The method comprises: acquiring a current environment pressure where the excavator is located; if the current environment pressure meets a starting condition, starting an engine of the excavator and acquiring an engine water temperature; if the engine water temperature meets an engine warming-up condition, executing an engine warming-up process anti-stalling control strategy to keep the engine speed constant at a preset speed; in the process that the engine speed is at the preset speed, when a hydraulic lock switch instruction is received, executing a hydraulic system warming-up anti-stalling control strategy; if the engine water temperature meets the engine warming-up condition, executing the engine warming-up process anti-stalling control strategy to keep the engine speed constant at the preset speed, comprising: comparing the engine water temperature with a preset water temperature; if the engine water temperature is less than or equal to the preset water temperature, performing engine warming-up through an engine warming-up program; in the process of engine warming-up, if a speed-up instruction is invalid and the hydraulic lock switch is invalid, increasing the engine idle speed at a preset time interval and a preset speed-up until the highest gear speed is reached; in the process that the engine idle speed reaches the highest gear speed, if the engine water temperature is greater than the preset water temperature, determining that the engine warming-up is completed; after the engine warming-up is completed, keeping the engine speed constant at the preset speed.

2. The method of claim 1, wherein, The method comprises: comparing the current environment pressure with a set value; if the current environment pressure is less than the set value, determining that the current environment pressure meets the starting condition; under the condition that the current environment pressure meets the starting condition, starting the engine of the excavator and acquiring the engine water temperature.

3. The method of claim 1, wherein, The hydraulic system warming-up anti-stalling control strategy at least comprises an engine power boosting strategy and a hydraulic loading anti-speed-drop strategy, and the method comprises: in the process that the engine speed is at the preset speed, when the hydraulic lock switch instruction is received, performing hydraulic control system warming-up through a hydraulic system warming-up program; in the process of hydraulic control system warming-up, respectively executing the engine power boosting strategy and the hydraulic loading anti-speed-drop strategy to complete the process of executing the hydraulic system warming-up anti-stalling control strategy.

4. The method of claim 3, wherein, The process of executing the engine power boosting strategy comprises: obtaining a target torque through a feedforward torque based on a pilot pressure and a torque curve of different pilot pressure sizes, wherein the target torque is the maximum value of each final torque under the condition of acquiring multiple pilot pressures in the operation process of the excavator; acquiring an actual speed in the working process of the excavator; correcting the actual speed through a set speed; adjusting the engine of the excavator through the target torque and the corrected actual speed to complete the process of executing the hydraulic system warming-up anti-stalling control strategy.

5. The method of claim 3, wherein, The process of executing the hydraulic loading anti-speed-drop strategy comprises: acquiring a real-time intake amount of the engine of the excavator, a real-time hydraulic oil temperature of the hydraulic system and a hydraulic loading rate of the hydraulic system; The intake amount correction parameter is determined according to the real-time intake amount, and the oil temperature correction parameter is determined according to the real-time hydraulic oil temperature; The hydraulic loading rate is corrected in real time through the intake amount correction parameter; The hydraulic loading rate after the intake amount correction is corrected in real time through the oil temperature correction parameter, so as to complete the process of the hydraulic loading anti-drop speed strategy.

6. The method of claim 1, wherein, In the process of keeping the engine speed at the preset speed, when receiving a hydraulic lock switch instruction, the hydraulic system warm-up anti-flameout control strategy is executed, and the vehicle control program is executed if the water temperature of the engine is greater than a preset water temperature and the hydraulic oil temperature is greater than a preset oil temperature. The device comprises:

7. An anti-flameout control device for a heat engine process of an excavator, characterized by, An acquisition unit is configured to acquire a current environmental pressure of the excavator; A starting unit is configured to start an engine of the excavator and acquire an engine water temperature if the current environmental pressure meets a starting condition; A first execution unit is configured to execute an engine warm-up process anti-flameout control strategy to keep the engine speed constant at a preset speed if the water temperature meets an engine warm-up condition; A second execution unit is configured to execute a hydraulic system warm-up anti-flameout control strategy when receiving a hydraulic lock switch instruction in the process of keeping the engine speed at the preset speed; The first execution unit comprises: A second comparison module is configured to compare the engine water temperature with a preset water temperature; A first execution module is configured to perform engine warm-up through an engine warm-up program if the engine water temperature is less than or equal to the preset water temperature; A speed-up module is configured to increase the idle speed of the engine according to a preset time interval and a preset speed-up until the highest gear speed is reached if a speed-up instruction is invalid and a hydraulic lock switch is invalid in the process of performing engine warm-up; A second determination module is configured to determine that the engine warm-up is completed if the engine water temperature is greater than the preset water temperature in the process of keeping the idle speed of the engine at the highest gear speed; A constant module is configured to keep the engine speed constant at the preset speed after the engine warm-up is completed. The starting unit comprises:

8. The apparatus of claim 7, wherein, A first comparison module is configured to compare the current environmental pressure with a set value; A first determination module is configured to determine that the current environmental pressure meets the starting condition if the current environmental pressure is less than the set value; A starting module is configured to start the engine of the excavator and acquire the engine water temperature if the current environmental pressure meets the starting condition. ​

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