Cold start and temperature regulation control method and system of excavator

Abstract

The invention discloses an excavator cold start and temperature regulation control method and system, and belongs to the technical field of excavators. The excavator cold machine starting and temperature adjusting control method comprises the steps that when the vehicle heating condition is met in the vehicle heating stage, a vehicle heating starting valve is controlled to be switched off, and pump current is increased for pressurization treatment; the hot vehicle starting valve is arranged to be a bucket flow collecting valve. Judging whether regulation and control stop conditions are met or not, and if yes, keeping the current pump current to heat the vehicle; otherwise, adjusting the engine rotating speed to the target rotating speed point; and the pump current is adjusted according to the actual torque error. The bucket flow collecting valve serves as a hot vehicle starting valve, use of parts is reduced, and cost is reduced; and the set rotating speed of the engine is adjusted in the vehicle heating process, so that the fuel consumption rate of the engine tends to be smaller under the current working condition, and the economical efficiency is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of excavators, and in particular to a method and system for cold start and temperature regulation control of an excavator. Background Art

[0002] If the hydraulic oil temperature of the excavator is too low or too high, it will cause a certain degree of damage to the engine and hydraulic system and shorten the service life. When the ambient temperature is low, the excavator needs to be warmed up before formal work. Usually, the action pressure holding method is used to raise the temperature of the engine coolant and the hydraulic oil of the hydraulic system to the required working temperature.

[0003] For example, CN113357231B discloses an automatic rapid warm-up system and method for use of a hydraulic excavator, including: detecting the hydraulic oil temperature, when the hydraulic oil temperature is lower than a certain threshold, adjusting the throttle knob to control the throttle to increase, controlling the proportional solenoid valve to reduce the displacement of the hydraulic pump, and preventing the hydraulic pump from having a large displacement at low temperatures; when the temperature is between the preset temperature range, the throttle knob simultaneously inputs a signal for the whole machine throttle to increase, and controls the proportional solenoid valve to keep the displacement of the hydraulic pump at a certain fixed displacement, and the flow of the hydraulic pump increases with the increase of the whole machine throttle signal, and the heat generated by the overflow further increases, thereby increasing the warm-up speed. This solution controls the flow of the hot start valve and the pump, increases the hydraulic oil circuit pressure, increases the post-processing exhaust temperature, and warms up the engine through the heat generated by the overflow, but does not consider the economic factors brought by the fuel consumption rate during the warm-up process.

[0004] For example, CN118498468A discloses a control method, device, storage medium and excavator system for an excavator system. The method uses the current return temperature as a judgment reference. When the current return temperature is less than or equal to the preset temperature threshold, the absolute value of the temperature difference is obtained, that is, the absolute value of the difference between the current return temperature and the preset temperature threshold. Finally, the first target opening is determined to be the opening corresponding to the absolute value of the temperature difference, and the opening of the first return oil throttle valve is adjusted to the first target opening, and the second return oil throttle valve is closed. Compared with the existing scheme, the return oil can be controlled not to pass through the cooler, thereby improving the heating speed, thereby solving the problem that the two parallel one-way valves in the excavator of the prior art cannot directly control the return oil not to pass through the cooler when the hydraulic oil temperature is low and needs to be heated quickly, resulting in too slow heating. Although the return oil is controlled not to pass through the cooler, the scheme does not consider the economic factor, that is, the hot engine process does not consider reducing the fuel consumption rate by adjusting the engine speed.

[0005] For another example, CN117514979A discloses a thermal management method, controller and thermal management system for an electric excavator. The method includes: obtaining the hydraulic oil temperature of the hydraulic oil in the hydraulic oil tank; when the hydraulic oil temperature is lower than the first preset oil temperature, adjusting the flow rate of the coolant in the first branch and the flow rate of the coolant in the second branch by controlling the opening of the reversing valve, so as to heat the hydraulic oil in the hydraulic oil tank through the coolant flowing in the first branch. The present application can adjust the flow rate of the coolant passing through the hydraulic oil tank by an electronically controlled proportional reversing valve according to the hydraulic oil temperature, heat the hydraulic oil by the heat of the coolant, increase the heating speed of the hydraulic oil in a low temperature environment, reduce the waiting time for warming up, enable the machine to quickly reach a normal working state, and reduce the workload of the electronic fan and energy consumption. This scheme controls the opening of the reversing valve according to the oil temperature to warm up the engine, and also does not consider the economic impact of the engine speed on the fuel consumption rate.

[0006] The existing technologies currently require the operator to operate the action handle to make the working device reach the working limit, increase the overflow heat through the overflow valve to achieve the warm-up effect, which takes up the driver's working time to operate, and long-term operation of the handle will also make the driver tired. At the same time, warming up the engine at a fixed set speed does not take into account energy consumption.

[0007] Therefore, there is an urgent need to develop a new excavator cold machine start-up and temperature regulation control method to solve the current defects and shortcomings. Summary of the invention

[0008] In view of this, the main purpose of the present invention is to provide a cold machine start-up and temperature adjustment control method for an excavator, in order to at least partially solve the above technical problems.

[0009] In order to achieve the above object, as a first aspect of the present invention, a method for cold start and temperature adjustment control of an excavator is proposed, comprising the following steps:

[0010] When the hot engine condition is met during the hot engine phase, the hot engine start valve is controlled to be disconnected, and the pump current is increased to perform pressurization processing; the hot engine start valve is set as a bucket confluence valve;

[0011] Determine whether the control stop condition is met. If so, keep the current pump current to warm up the engine; otherwise, adjust the engine speed to the target speed point and adjust the pump current according to the actual torque error.

[0012] As a second aspect of the present invention, a cold start and temperature regulation control system for an excavator is proposed, comprising: a pump, a main valve, a hot start valve and a control unit, wherein the hot start valve is configured as a bucket combining valve; wherein the output end of the pump is connected to the main valve, the main valve is connected to an oil tank via the hot start valve, the oil tank is connected to the main valve via an overflow valve, the input end of the pump is connected to the oil tank via an engine, the control unit is electrically connected to an oil temperature sensor, the oil temperature sensor is used to collect the temperature of the hydraulic oil, and the control unit is used to compare the hydraulic oil temperature with the working temperature range and control the action of the main valve and the hot start valve.

[0013] Based on the above technical solution, it can be seen that the excavator cold machine start and temperature adjustment control method and system of the present invention have at least one of the following beneficial effects compared with the prior art:

[0014] 1. During the warm-up process, determine the point close to the optimal fuel economy curve according to the torque range and speed range corresponding to the current temperature, and adjust the engine speed setting to make it tend to a smaller fuel consumption rate under the current working conditions, thereby improving economy;

[0015] 2. The bucket confluence valve is used as the hot start valve, which does not require the addition of more parts and reduces costs;

[0016] 3. The oil circuit is cooled and controlled by a fan, which is more controllable than traditional coolant cooling. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below.

[0018] Figure 1 It is a flow chart of the cold machine start and temperature adjustment control method of the excavator of the present invention;

[0019] Figure 2 It is a structural framework diagram of the excavator cold machine start and temperature adjustment control system of the present invention;

[0020] Figure 3 It is a schematic diagram of a universal characteristic curve of the cold machine start-up and temperature regulation control method of an excavator of the present invention.

[0021] In the above drawings, the meanings of the reference numerals are as follows:

[0022] 1. Pump; 2. Main valve; 3. Hot start valve; 4. Fuel tank; 5. Overflow valve; 6. Fuel cylinder. DETAILED DESCRIPTION

[0023] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with specific embodiments and with reference to the accompanying drawings.

[0024] The terms used in the present invention are only for the purpose of describing specific embodiments, and are not intended to limit the embodiments of the present invention. The singular forms "a", "said" and "the" used in the embodiments of the present invention and the appended claims are also intended to include plural forms, unless the context clearly indicates other meanings.

[0025] The present application found that the existing technologies currently require the operator to operate the action handle to make the working device reach the working limit, increase the overflow heat through the overflow valve to achieve the warm-up effect, which requires the driver's working time to operate. The long-term operation of the handle will also make the driver tired. At the same time, warming up at a fixed set speed does not take into account energy consumption. After in-depth research, it is found that the hot-up control is achieved by detecting the hydraulic oil temperature, and the mode switching between normal operation and cooling control is achieved to achieve automatic adjustment of the excavator's working temperature. At the same time, the engine economy is taken into account to make it as close to the optimal economic range as possible within a reasonable speed range.

[0026] The bucket merging valve is set in the structure of the normal working stage of the excavator. Its function is to merge the oil from different oil pumps 1 and supply it to the bucket cylinder 6 according to work requirements to increase the movement speed and force of the bucket. For example, when excavation, loading and unloading and other operations require oil with a large flow and pressure to drive the bucket, the bucket merging valve will work to connect the oil circuit to realize the merging function, so it will not participate in the oil circuit in and out during the warm-up stage. The cylinder here does not simply refer to the bucket cylinder, it can be the cylinder of any actuator; when the bucket is moving, the bucket merging valve is responsible for merging the oil flow to the bucket. When the bucket is not moving, the bucket merging valve does not play a merging role to ensure that the working oil circuit supplies oil to the actuator.

[0027] Therefore, the inventors propose a method for cold start and temperature regulation control of an excavator, comprising the following steps:

[0028] like Figure 1 As shown, in the hot-start stage, when the hot-start conditions are met, the hot-start start valve 3 is controlled to be disconnected, and the current of the pump 1 is increased for pressurization processing; the hot-start start valve 3 is set as a bucket confluence valve; in the whole machine structure, the bucket confluence valve is used as the hot-start start valve 3, which expands the function of the bucket confluence valve, and there is no need to add other valves to hold pressure to cut off the oil circuit;

[0029] Determine whether the control stop condition is met. If so, keep the current pump 1 current to warm up the engine; otherwise, adjust the engine speed to the target speed point and adjust the pump 1 current according to the actual torque error.

[0030] When the hot engine condition is met, the bucket merging valve is electrically closed and shut off. The closing and shutting here refer to the valve core being in the disconnected position, that is, the valve core of the bucket merging valve is in the Figure 2 In the right position, the main valve 2 is in the middle position, and the oil path flowing back to the oil tank through the bucket merging valve is cut off.

[0031] Set the working temperature range, detect the temperature of the hydraulic oil under the current working conditions, and compare the temperature of the hydraulic oil with the working temperature range. When the temperature of the hydraulic oil is lower than the working temperature range, it is the warm-up stage; when the temperature of the hydraulic oil is within the working temperature range, it is the normal working stage; when the temperature of the hydraulic oil is higher than the working temperature range, it is the cooling stage.

[0032] The current working condition corresponds to a target torque range, a target speed range and a preset torque error. The actual torque error is obtained by subtracting the current torque value of the current working condition from the maximum value of the target torque range. When the actual torque error is less than the preset torque error, the current pump 1 current is maintained. The determination of the target torque range and the target speed range depends on the consideration of limiting and calibrating the speed and torque of the engine to avoid cylinder decoupling or other failures.

[0033] The hot engine condition is that the safety lock switch is in the on state and the excavator is not moving. The safety lock switch is located in the cab and the on and off state of the safety lock switch can be controlled by the driver.

[0034] The control stop condition is that the displacement of pump 1 exceeds the preset maximum displacement or the engine load exceeds the preset maximum load. While increasing the current, on the one hand, the displacement value of pump 1 is monitored to see if it reaches the preset maximum displacement. If it exceeds the preset maximum displacement, the current of pump 1 will not be increased; on the other hand, if the engine load exceeds the preset maximum load, the current value will not be increased and the current load will be maintained for circulating warm-up.

[0035] When the excavator is in normal working state, that is, when the hydraulic oil temperature reaches the working temperature range, the control unit sends a command to the display to prompt the driver that the warm-up is over and the operation can be carried out normally. At the same time, the warm-up start valve 3 is opened to allow the hydraulic oil to flow to the working oil circuit to realize the normal operation of the excavator. The main valve 2 plays the role of distributing the flow direction of the hydraulic oil, receiving the high-pressure hydraulic oil from the pump 1, and distributing the hydraulic oil to various actuators of the excavator, such as the boom cylinder 6, the arm cylinder 6, the bucket cylinder 6, etc. according to different operation instructions, so as to realize the corresponding actions, such as controlling the lifting and lowering of the boom, the extension and retraction of the arm, and the digging and unloading of the bucket.

[0036] When the excavator is in a cooling state, that is, when it is detected that the hydraulic oil temperature exceeds the working temperature range, the cooling fan is turned on for cooling control. The fan setting current is obtained according to the corresponding relationship between the hydraulic oil temperature and the fan speed, and the fan speed is controlled to reduce the temperature of the hydraulic oil. When the hydraulic oil temperature is lower than the maximum value of the ideal working temperature, the fan maintains a lower speed to achieve the purpose of rapid response when the fan is turned on.

[0037] Among them, since the relief valve 5 is in a closed state, the hydraulic oil that initially reaches the inlet of the relief valve 5 no longer flows, so the hydraulic pump continues to work, which will cause the system pressure to continue to increase. The pressure gradually increases, which will generate some heat and form pressure buildup. Pressure buildup will cause the system pressure to increase abnormally, which may cause damage to hydraulic components, such as seal rupture, pipeline burst, etc. In order to prevent pressure buildup, the hydraulic system presets an overflow pressure. When the pressure of the hydraulic oil is greater than the overflow pressure, the relief valve 5 opens, and the hydraulic oil returns to the oil tank 4 through the relief valve 5 to avoid excessive current oil circuit pressure at the inlet of the relief valve 5, allowing the hydraulic oil to flow, thereby releasing excess pressure, and also playing a role in pressure relief protection. The pump 1 continues to pump oil from the oil tank 4 through the engine, and the temperature of the hydraulic oil in the oil circuit continues to rise, and the oil circuit circulates to achieve the warm-up process.

[0038] The target torque range and target speed range of the current working condition are obtained by looking up the table. Specifically, according to the current hydraulic oil pressure value and engine speed value, the corresponding row and column are found in the table to determine the target torque range and target speed range under the current working condition. If the data points in the table are discrete and the actual measured value is between two data points, an interpolation algorithm is used to calculate a more accurate target value.

[0039] The target torque range and the target speed range are combined with the universal characteristic curve to obtain the target speed point. The process of determining the target speed point takes into account minimizing fuel consumption, that is, achieving the lowest fuel consumption as much as possible during the warm-up phase. Therefore, the speed point corresponding to the part of the equal fuel consumption line with the lowest value in the area is found, that is, along the optimal economy curve, the speed value corresponding to the equal fuel consumption line that falls within the target area and has the relatively lowest fuel consumption is found as the target speed point, which can make the engine consume relatively less fuel when the engine is warmed up.

[0040] In a preferred embodiment, Figure 2As shown, the present invention also discloses an excavator cold engine start and temperature adjustment control system, including a pump 1, a main valve 2, a hot engine start valve 3 and a control unit, the output end of the pump 1 is connected to the main valve 2, the main valve 2 is connected to the oil tank 4 through the hot engine start valve 3, the oil tank 4 is connected to the main valve 2 through the overflow valve 5, the input end of the pump 1 is connected to the oil tank 4 through the engine, the control unit is electrically connected to an oil temperature sensor, the oil temperature sensor is used to collect the temperature of the hydraulic oil, the control unit is used to compare the hydraulic oil temperature with the working temperature range and control the action of the main valve 2 and the hot engine start valve 3, the oil temperature sensor is installed in the hydraulic system, and is used to accurately collect the temperature of the hydraulic oil, and provide a basis for the control unit to judge the temperature state of the hydraulic oil, so as to take the corresponding temperature adjustment process later.

[0041] During the warm-up phase, the driver first sends a warm-up control command to the controller through the display. When the control unit receives the warm-up command, it detects the temperature of the hydraulic oil, which is collected by the oil temperature sensor. Assuming that the ideal working temperature range of the excavator is T1-T2, when the hydraulic oil temperature collected by the oil temperature sensor is lower than T1, and the safety lock switch is turned on, and the excavator does not move, the warm-up action begins. When the warm-up conditions are met, the current of the hot start valve 3 is controlled to be maximum, so that the valve core of the hot start valve 3 is in a disconnected state, preventing the oil from flowing back to the oil tank 4 through the hot start valve 3. At the same time, the current of the pump 1 is gradually increased, so that the displacement of the pump 1 gradually increases, thereby increasing the pressure in the oil circuit. When the pressure in the oil circuit reaches the preset overflow pressure point, the oil overflows through the overflow valve 5, and the overflow resistance generates heat to accelerate the temperature rise of the oil. The schematic diagram is shown as follows Figure 2 The displacement of pump 1 corresponds to the opening of pump 1, and the current flow rate is calculated based on the current speed and the current displacement value.

[0042] During the pressurization process, the target torque range and target speed range that the engine can withstand at the current temperature are obtained by looking up the table according to the current oil temperature. According to the engine fuel economy curve, the corresponding target speed point on the economic curve that can achieve maximum power is found within the target torque range and target speed range, and sent to the engine as the set speed for speed control. At the same time, the current of pump 1 is controlled according to the actual current torque value and the maximum ideal torque value, so that the current torque value at the engine end reaches the torque of the current operating point. The difference between the maximum ideal torque value and the current torque is calculated, and the current value of pump 1 is closed-loop controlled through the difference. The difference is recorded as the actual torque error, and the deviation threshold of the difference is recorded as the preset torque error. When the actual torque error is less than the preset torque error, the control of pump 1 current adjustment is stopped to maintain the current value of pump 1.

[0043] The present invention will be further described below by specific embodiments. It should be noted that the following embodiments are only illustrative and are not intended to limit the present invention. Based on the embodiments of the present invention shown below, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the embodiments of the present invention.

[0044] Example 1

[0045] The working temperature range is T1-T2. The temperature of the hydraulic oil is detected by the oil temperature sensor and compared with the working temperature range T1-T2. When the temperature of the hydraulic oil is lower than T1, the engine is warmed up. During the warm-up process, the temperature is further divided into temperature segments [T 01 , T 02 , T1], when the temperature of the hydraulic oil is less than T 01 At this time, by looking up the table, the maximum speed and torque range of the engine at the current temperature are [n 01 , n 01max ],[t 01 , t 01max ], in this case, the speed n1 and torque t1 corresponding to the optimal operating point of the engine are calculated, the set speed is set to n1, and the pump current is increased at the same time, so that the torque tends to the set torque t1. When the temperature reaches T 02 When the maximum speed and torque range of the engine at the current temperature are obtained by re-checking the table, they are [n 02 , n 02max ][t 02 , t 02max ], repeat the above steps, when the temperature reaches T1, stop warming up and perform normal operation. Divide the current torque value of the current working condition and the maximum value of the target torque range to obtain the difference, and set the torque error to 5%. When the difference is less than the torque error of 5%, maintain the current pump current.

[0046] like Figure 3 As shown in the figure, the line connecting the tangent points of the equal power curve and the equal fuel consumption curve is the optimal fuel economy curve. The point closest to the small circle of the equal fuel consumption curve within the maximum speed and torque range is the target speed point, which corresponds to a target torque value and a target speed value. The dashed line where the tangent point is located is the fuel economy curve, and the speed point is found so that it falls on the dashed line. The speed is determined to be a fixed value, and the torque is found so that the intersection with the speed falls on the dashed line, and the current power is the maximum.

[0047] In the control system of the excavator, a table of the correspondence between the hydraulic oil temperature and the fan speed is established in advance through data collection. For example, when the hydraulic oil temperature is 50°C, the corresponding fan speed is set to 1000 rpm; when the hydraulic oil temperature is 60°C, the corresponding fan speed is set to 1500 rpm, etc. The table covers different hydraulic oil temperature ranges and the corresponding fan speed values, providing basic data for subsequent interpolation calculations. A temperature sensor that can accurately measure the hydraulic oil temperature is installed in the hydraulic system. It monitors the actual temperature of the hydraulic oil at all times and transmits the temperature signal to the control system of the excavator in real time. At the same time, a controller for controlling the fan motor current is set to adjust the fan speed by changing the current size. The smaller the current, the higher the fan speed and the stronger the heat dissipation capacity. The inverse proportional solenoid valve is used to keep the fan at a lower speed, which can make it respond quickly when working.

[0048] When the excavator is in a cooling state (such as when the hydraulic oil temperature is too high after long-term high-intensity operation or when the external ambient temperature is high, causing the hydraulic oil to heat up), the hydraulic oil temperature sensor will continuously collect the actual temperature value of the current hydraulic oil and transmit the value to the control system. After the control system receives the current hydraulic oil temperature, it will compare it with the pre-set suitable hydraulic oil working temperature range. If the current temperature exceeds the upper limit of the working temperature range, the control system determines that the fan needs to be started for cooling operation, and enters the process of calculating the fan setting current based on the corresponding relationship.

[0049] The process of using the linear interpolation formula to calculate the corresponding fan setting current is as follows: Assuming T a 、T b represents the two end temperatures of the temperature interval (in this embodiment, T a =50℃, T b =60℃), N a 、N b Indicates the corresponding fan speed interval endpoint value (N a =1000 rpm, N b =1500 rpm), T represents the actual hydraulic oil temperature (55°C), N 风扇 Indicates the fan speed that needs to be calculated. The calculation formula is as follows:

[0050]

[0051] Substituting the values ​​into the =1250 rpm, and then according to the corresponding relationship between fan speed and current, the set current value required to achieve the fan speed of 1250 rpm is calculated, and the corresponding current is 2.5A by looking up the table. The control system sends the calculated fan set current value of 2.5A to the current controller of the fan motor. The current controller adjusts the current output to the fan motor according to the received command, so that the fan motor runs according to the set current, so that the fan reaches the calculated speed of 1250 rpm.

[0052] The present invention gradually increases the displacement of pump 1 by controlling the current of hot start valve 3 and the current of pump 1, so that the oil circuit pressure increases automatically, and the post-processing exhaust temperature is increased, and the driver does not need to perform related operations, thereby reducing the driver's fatigue level; at the same time, the bucket confluence valve is used as the hot start valve 3, reducing the use of parts and reducing costs. The present invention controls the set speed of the engine during the hot start process, so that it tends to a smaller fuel consumption rate under the current working conditions, thereby improving economy.

[0053] In the description of the present invention, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In the present invention, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in the present invention and the features of the different embodiments or examples, without contradiction.

[0054] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0055] Any process or method description in a flowchart or otherwise described herein may be understood to represent a module, segment or portion of code comprising one or more executable instructions for implementing the steps of a custom logical function or process, and the scope of the preferred embodiments of the present invention includes alternative implementations in which functions may not be performed in the order shown or discussed, including performing functions in a substantially simultaneous manner or in reverse order depending on the functions involved, which should be understood by technicians in the technical field to which the embodiments of the present invention belong.

[0056] In the several embodiments provided by the present invention, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. For example, the device embodiments described above are only schematic. For example, the division of the units is only a logical function division. There may be other division methods in actual implementation. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0057] In addition, each functional unit in each embodiment of the present invention may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of hardware plus software functional units.

[0058] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A method for cold start and temperature regulation control of an excavator, characterized in that: The steps include: When the hot engine condition is met during the hot engine phase, the hot engine start valve is controlled to be disconnected, and the pump current is increased to perform pressurization processing; the hot engine start valve is set as a bucket confluence valve; It is determined whether the control stop condition is met, if so, the current pump current is maintained to warm up the engine; otherwise, the engine speed is adjusted to the target speed point, and the pump current is adjusted according to the actual torque error.

2. The excavator cold machine start and temperature adjustment control method according to claim 1, characterized in that: Set the working temperature range, detect the temperature of the hydraulic oil in the current working condition, compare the temperature of the hydraulic oil with the working temperature range, when the temperature of the hydraulic oil is lower than the working temperature range, it is the warm-up stage, when the temperature of the hydraulic oil is within the working temperature range, it is the normal working stage, and when the temperature of the hydraulic oil is higher than the working temperature range, it is the cooling stage.

3. The excavator cold start and temperature adjustment control method according to claim 2, characterized in that: The current operating condition corresponds to a target torque range, a target speed range and a preset torque error. The actual torque error is obtained by subtracting the current torque value of the current operating condition from the maximum value of the target torque range. When the actual torque error is less than the preset torque error, the current pump current is maintained.

4. The excavator cold start and temperature adjustment control method according to claim 2, characterized in that: When the excavator is in the normal working stage, the hot start valve is controlled to be turned on, and the hydraulic oil flows to the working oil circuit.

5. The excavator cold start and temperature adjustment control method according to claim 2, characterized in that: When the excavator is in the cooling stage, the fan setting current is obtained according to the corresponding relationship between the temperature of the hydraulic oil and the fan speed, and the fan speed is controlled to reduce the temperature of the hydraulic oil.

6. The excavator cold start and temperature adjustment control method according to claim 3, characterized in that: The target torque range and the target speed range of the current working condition are both obtained by looking up a table, and the target torque range and the target speed range are combined with a universal characteristic curve to obtain the target speed point.

7. The excavator cold start and temperature adjustment control method according to claim 1, characterized in that: The hot engine condition is that the safety lock switch is in the on state and the excavator is not moving.

8. The excavator cold start and temperature adjustment control method according to claim 1, characterized in that: The control stop condition is that the displacement of the pump exceeds a preset maximum displacement or the engine load exceeds a preset maximum load.

9. The excavator cold start and temperature adjustment control method according to claim 1, characterized in that: An overflow pressure is preset, and when the pressure of the hydraulic oil is greater than the overflow pressure, the overflow valve is opened.

10. An excavator cold start and temperature adjustment control system, characterized in that: It includes a pump, a main valve, a hot car starting valve and a control unit; the hot car starting valve is set as a bucket combining valve; wherein the output end of the pump is connected to the main valve, the main valve is connected to a fuel tank through the hot car starting valve, the fuel tank is connected to the main valve through a relief valve, the input end of the pump is connected to the fuel tank through an engine, the control unit is electrically connected to an oil temperature sensor, the oil temperature sensor is used to collect the temperature of the hydraulic oil, the control unit adopts the excavator cold machine starting and temperature adjustment control method as described in any one of claims 1 to 9, which is used to compare the hydraulic oil temperature with the working temperature range and control the action of the main valve and the hot car starting valve.

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