Flow regulation loop of cooling system of cotton picker and control method

Abstract

The invention discloses a flow adjusting loop of a cotton picker cooling system and a control method, and belongs to the technical field of agricultural machineries, the flow adjusting loop of the cotton picker cooling system comprises a first electric drive water pump loop and a second electric drive water pump loop which are connected in parallel, and each of the first electric drive water pump loop and the second electric drive water pump loop comprises a plurality of branches; heat production components of the cotton picker are grouped according to the required cooling flow, the heat production components in different groups are connected to different branches, each branch is provided with a self-operated temperature control valve, and each self-operated temperature control valve controls the cooling flow passing through a valve body according to the cooling flow required by the heat production component on the corresponding branch. The technical problems that under different cooling requirements of multiple motors and controllers, a traditional cooling system cannot meet all heat dissipation requirements at the same time, flow and lift distribution is uneven, and energy efficiency is low are solved.

Description

Technical Field

[0001] The invention relates to the technical field of agricultural machinery, and in particular to a flow regulating loop and a control method of a cooling system of a cotton picker. Background Art

[0002] With the continuous maturity and upgrading of cotton picker technology, the market has begun to develop and produce electric cotton picker products, which are more efficient and energy-saving, in line with the current trend of electrification of construction machinery; and the difference between electric cotton pickers and traditional cotton pickers is that they have multiple motors and motor controllers working at the same time, which will generate a lot of heat during the operation, so a cooling circulation system is required to dissipate heat.

[0003] At present, there is no precedent in China for the whole cotton picking machine to be driven by an electric motor. In the automotive industry, most new energy vehicles are equipped with a single motor, and their cooling system uses only one main circuit to connect the motor, controller, cooler and other components in series for cooling. The four-row cotton picking baler newly developed by our company uses motors for walking, picking head, fan, and hydraulic pump drive. The total number of motors and controllers adds up to more than ten. Compared with the automotive industry, such a large number of motors and controllers are more complicated, and the cooling power required for each is also different. If only one circuit is used in series to form a system: due to the different working powers of different motors, the required cooling flow is also different, and it is difficult to simultaneously meet the requirements that all motors work in the most suitable temperature range; and if so many motors and controllers are connected in series in one circuit, the water resistance is too large, and the conventional electronic water pump capacity is difficult to meet its flow and head requirements. Summary of the invention

[0004] The invention provides a flow regulating loop and a control method of a cooling system of a cotton picker, so as to solve the technical problem that the heat dissipation requirement of an electric cotton picker is difficult to meet.

[0005] According to one aspect of the present invention, there is provided a flow regulating circuit of a cotton picker cooling system, comprising a first electric-driven water pump circuit and a second electric-driven water pump circuit connected in parallel, wherein the first electric-driven water pump circuit and the second electric-driven water pump circuit each comprise a plurality of branches, and the heat-generating components of the cotton picker are grouped according to the required cooling flow rate, and heat-generating components of different groups are connected to different branches, and a self-operated temperature control valve is provided on each branch, and each self-operated temperature control valve controls the cooling flow rate through the valve body according to the cooling flow rate required by the heat-generating component on the corresponding branch.

[0006] Optionally, the first electric-driven water pump includes a first branch, a second branch and a third branch. The heat-generating elements connected to the first branch include a generator and a generator controller. The heat-generating elements connected to the second branch include a left front travel motor and a right front travel motor. The heat-generating elements connected to the third branch include a left cotton picking head motor and a right cotton picking head motor.

[0007] Optionally, the second electric drive water pump circuit includes a fourth branch, a fifth branch and a sixth branch, the heat-generating element connected to the fourth branch is a dual-drive controller, the heat-generating element connected to the fifth branch is a fan motor and a single-drive controller of the fan motor, and the heat-generating element connected to the sixth branch is a hydraulic pump motor and a rear travel motor.

[0008] Optionally, the self-operated temperature control valve includes a valve body, a valve core and a temperature control component. The valve core is movably arranged in the flow channel inside the valve body. The temperature control component includes a temperature sensing component and a driving component. The temperature sensing component is located in the coolant of the corresponding branch and drives the driving component to move through the principle of thermal expansion and contraction, and then drives the valve core to move through the driving component, so that the conduction area of ​​the valve core flow channel is increased.

[0009] Optionally, the driving component includes a valve cover connected to the valve body and an adjusting spring arranged in the valve cover, the valve core is connected to the adjusting spring, and the temperature sensing component includes a temperature sensing bag, which is connected to the valve cover through a conduit. The temperature sensing bag contains liquid or gas to transfer the force generated by thermal expansion and contraction of the liquid or gas to the valve core through the conduit.

[0010] Optionally, a temperature scale is provided on the valve cover.

[0011] Optionally, the valve body forms an opening and closing ring corresponding to the position of the valve core in the flow channel, and a sealing step and a through hole are formed in the opening and closing ring. The sealing step is used to cooperate with the valve body, and the diameter of the through hole is smaller than the diameter of the valve body.

[0012] Optionally, a pressure sensor for detecting the outlet water pressure of the electric water pump is connected to both the first electric water pump circuit and the second electric water pump circuit.

[0013] Optionally, the flow regulating loop of the cotton picker cooling system also includes an air cooler arranged on the loop, and the air cooler is connected in parallel with an expansion pot, which is used to accommodate the expansion of the system's coolant, stabilize the system pressure, and remove air released by the water during the heating process.

[0014] According to another aspect of the present invention, a control method for a cooling system of a cotton picker is provided, using the flow regulating circuit of the cooling system of the cotton picker, characterized in that the method comprises the following steps:

[0015] When the machine is started, the electric drive water pump works at the initial speed. At this time, the radiator does not work, that is, the cooling system temporarily does not have a cooling effect, so that the motor and controller can quickly heat up to their preset working temperature;

[0016] When it is detected that the temperature of a motor or controller is greater than 45°C, the radiator is started and the cooling system begins to work; the balance temperature of the self-operated temperature control valve of each branch is set according to their respective needs;

[0017] In order to avoid overheating caused by power overflow of the electric drive water pump, the total water resistance of the circuit of the first electric drive water pump is calculated to ensure that the output head of the first electric drive water pump is greater than the total water resistance of the circuit, so as to meet the circulation demand of the cooling system and avoid power overflow; the total water resistance of the circuit of the second electric drive water pump is calculated to ensure that the output head of the second electric drive water pump is greater than the total water resistance of the circuit, so as to meet the circulation demand of the cooling system and avoid power overflow;

[0018] The outlet of the electric-driven water pump is equipped with a pressure sensor. When it is monitored that the outlet pressure of the water pump is smaller than the required head, the PWM duty cycle is increased and the water pump speed is increased, that is, the output head is increased; when it is monitored that the outlet pressure is larger than the required head, the PWM duty cycle is reduced and the water pump speed is reduced.

[0019] In summary, the present application includes at least one of the following beneficial technical effects:

[0020] In response to the heat dissipation requirements under complex working conditions of multiple motors and multiple controllers, this solution adopts a dual electric drive water pump parallel structure, dividing the cooling system into two main circuits, each circuit is further subdivided into multiple branches, and each branch is independently designed according to the cooling requirements, avoiding the problem of excessive water resistance caused by a single circuit in series, effectively reducing the system water resistance, and ensuring that the water pump output head meets the circulation requirements. Secondly, by installing a self-operated temperature control valve on each branch, the cooling flow is automatically adjusted. The self-operated temperature control valve uses the principle of thermal expansion and contraction of the coolant to adjust the valve core position according to the real-time temperature requirements of the components, dynamically control the flow, so that each component is always in the optimal operating temperature range, avoiding the disadvantage of the traditional cooling system that cannot meet the heat dissipation requirements of all equipment. Thirdly, the electric drive water pump adjusts the speed through the PWM signal, and the output flow and head are dynamically adjusted as the cooling demand changes, avoiding the overheating problem caused by power overflow, while improving the working efficiency and life of the water pump. In addition, pressure sensors and temperature sensors are added to the system design to monitor the circuit water pressure and coolant temperature in real time, ensure that the water pump works within a safe range, and stabilize the system pressure and exhaust gas through air coolers and expansion pots to further improve system reliability. Through the above design, the solution successfully solves technical problems such as the inability of traditional cooling systems to meet all heat dissipation requirements at the same time under different cooling requirements of multiple motors and controllers, uneven distribution of flow and head, and low energy efficiency, so that the electric cotton picker can operate stably under high-load and complex working conditions, significantly improving the heat dissipation efficiency and system adaptability.

[0021] In addition to the above-described purposes, features and advantages, the present invention has other purposes, features and advantages. The present invention will be further described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The drawings constituting a part of this application are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0023] Figure 1 This is a schematic diagram of a flow regulating circuit of a cooling system of a cotton picking and baling machine of the present invention;

[0024] Figure 2 This is a structural diagram of the self-operated temperature control valve of the present invention;

[0025] Figure 3 This is a control logic diagram of a flow regulating loop of a cooling system of a cotton picking and baling machine of the present invention;

[0026] Figure 4 This is a schematic diagram of an alternative solution for the flow regulating circuit of the cooling system of the cotton picking and baling machine of the present invention.

[0027] Legend:

[0028] 1. Electric water pump; 2. Pressure sensor; 3. Temperature sensor; 4. Ball valve; 5. Filter; 6. Self-operated temperature control valve; 7. Air cooler; 8. Expansion pot; 9. Mechanical water pump; 10. Electric temperature control valve; 11. Valve body; 12. Valve core; 13. Adjustment spring; 14. Valve cover; 15. Temperature scale; 16. Temperature adjustment hole; 17. Conduit; 18. Temperature sensing package plug nut, etc.; 19. Temperature sensing package; 20. Electric regulating valve. DETAILED DESCRIPTION

[0029] The embodiments of the present invention are described in detail below with reference to the accompanying drawings. However, the present invention can be implemented in many different ways as defined and covered below.

[0030] The following is combined with Figure 1-4 This application is described in further detail.

[0031] The embodiment of the present application discloses a flow regulating loop and a control method of a cooling system of a cotton picker.

[0032] Reference Figure 1 The flow regulating circuit of the cotton picker cooling system includes a first electric-driven water pump 1 circuit and a second electric-driven water pump 1 circuit connected in parallel. The first electric-driven water pump 1 circuit and the second electric-driven water pump 1 circuit each include multiple branches. The heat-generating components of the cotton picker are grouped according to the required cooling flow rate. Different groups of heat-generating components are connected to different branches. A self-operated temperature control valve 6 is provided on each branch. Each self-operated temperature control valve 6 controls the cooling flow rate through the valve body according to the cooling flow rate required by the heat-generating component on the corresponding branch.

[0033] The flow requirements of the cooling system are respectively borne by the first electric drive water pump 1 circuit and the second electric drive water pump 1 circuit connected in parallel, and each circuit is further subdivided into multiple branches, so that different heat-generating components are reasonably grouped according to their actual cooling requirements and connected to their respective branches. The role of this design is to accurately match the heat dissipation requirements of different components and avoid the problem of uneven flow and cooling efficiency that may occur in a single circuit design. A self-operated temperature control valve 6 is set on each branch, and the flow size of the valve body is automatically adjusted according to the real-time temperature requirements of the component by using the principle of thermal expansion and contraction, thereby realizing dynamic flow regulation. The purpose of this design is to ensure that each heat-generating component always operates in its optimal operating temperature range, avoid overcooling or overheating, and improve the overall efficiency of the cooling system. In addition, grouping components according to cooling requirements and allocating them to different branches can effectively reduce the water resistance of each branch, reduce the excessive requirements for the water pump head, thereby reducing the system operation power consumption, extending the service life of the equipment, and improving the reliability and adaptability of the system.

[0034] Specifically, the first electric drive water pump 1 includes a first branch, a second branch and a third branch. The heat generating elements connected to the first branch include a generator and a generator controller. The heat generating elements connected to the second branch include a left front travel motor and a right front travel motor. The heat generating elements connected to the third branch include a left cotton picking head motor and a right cotton picking head motor. The flow of the first electric drive water pump 1 is distributed to three independent branches, which are respectively connected to heat generating elements with different functions. Its function is to independently adjust the flow according to the heat dissipation requirements of each group of components, so as to improve the efficiency and adaptability of the cooling system. The first branch is connected to the generator and the generator controller, because of its large power and high heat dissipation requirements, it requires a relatively large cooling flow; the second branch is connected to the left front travel motor and the right front travel motor. These two motors have the same operating power and similar heat dissipation requirements under most working conditions, and can achieve efficient cooling through the same branch; the third branch is connected to the left cotton picking head motor and the right cotton picking head motor. The load and heat dissipation requirements of these two motors are also relatively close. Being independent as a branch can better meet their cooling requirements. The advantage of this setting is that by grouping components with different heat dissipation requirements and assigning them to independent branches, it can not only reduce the water resistance of a single branch, but also ensure that the flow of each branch matches its heat dissipation requirements, avoiding resource waste and uneven cooling problems.

[0035] The second electric drive water pump 1 circuit includes a fourth branch, a fifth branch and a sixth branch. The heat-generating element connected to the fourth branch is a dual-drive controller, the heat-generating element connected to the fifth branch is a fan motor and a single-drive controller of the fan motor, and the heat-generating elements connected to the sixth branch are a hydraulic pump motor and a rear travel motor.

[0036] The second electric drive water pump 1 circuit is subdivided into three branches and allocated according to the heat dissipation requirements of different components. The purpose is to achieve efficient distribution and precise adjustment of cooling flow, and ensure that the cooling requirements of each heat-generating component are met. The fourth branch is connected to the dual-drive controller. Since the dual-drive controller needs to control two motors at the same time, the working power is large and the heat dissipation requirement is high, so a separate branch can provide sufficient cooling flow; the fifth branch is connected to the fan motor and the single-drive controller of the fan motor. These components are in a shutdown state in the road transportation mode and do not need to be cooled; while in the field harvesting mode, they run synchronously at high speed and have high thermal power. Merging them into one branch can save cooling resources and ensure cooling efficiency; the sixth branch is connected to the hydraulic pump motor and the rear travel motor. The working power of these two components is similar and the cooling requirements are similar. Therefore, allocating them to the same branch can simplify the system design, reduce water resistance and improve flow utilization efficiency. The purpose of this design is to avoid the problem of uneven flow distribution in a single circuit by grouping components according to heat dissipation requirements, while reducing the water resistance burden of each branch, so that the water pump can work more efficiently.

[0037] Reference Figure 2 The self-operated temperature control valve 6 includes a valve body, a valve core and a temperature control component. The valve core is movably arranged in the flow channel in the valve body. The temperature control component includes a temperature sensing component and a driving component. The temperature sensing component is located in the coolant of the corresponding branch and drives the driving component to move through the principle of thermal expansion and contraction, and then drives the valve core to move through the driving component, so that the conduction area of ​​the valve core flow channel is increased. After the temperature change of the coolant is sensed by the temperature sensing component, the thermal expansion and contraction effect is used to achieve automatic adjustment. When the temperature of the coolant rises, the liquid or gas in the temperature sensing component generates a displacement force due to thermal expansion and contraction, and the driving component moves accordingly and drives the valve core to move, increasing the conduction area of ​​the valve core and increasing the coolant flow rate, thereby improving the heat dissipation efficiency; when the temperature of the coolant decreases, the liquid or gas in the temperature sensing component contracts, and the driving component drives the valve core to return to its position, reducing the conduction area, reducing the flow rate, and avoiding overcooling.

[0038] The driving component includes a valve cover connected to the valve body and an adjusting spring arranged in the valve cover, the valve core is connected to the adjusting spring, and the temperature sensing component includes a temperature sensing bag, which is connected to the valve cover through a conduit. The temperature sensing bag contains liquid or gas, so as to transmit the force generated by the thermal expansion and contraction of the liquid or gas to the valve core through the conduit. When the temperature of the coolant rises, the liquid or gas in the temperature sensing bag expands due to the thermal expansion effect, and the expansion force is transmitted to the adjusting spring in the driving component through the conduit, pushing the valve core to move, increasing the flow channel conduction area, thereby increasing the coolant flow rate and improving the heat dissipation efficiency; when the temperature of the coolant decreases, the liquid or gas in the temperature sensing bag shrinks due to the contraction effect, and the adjusting spring drives the valve core back to its position through its elastic force, reducing the flow channel conduction area, reducing the coolant flow rate, and preventing the system from overcooling.

[0039] The valve cover is provided with a temperature scale. The purpose of providing a temperature scale on the valve cover of the self-operated temperature control valve 6 is to provide a visual temperature adjustment reference for the cooling system, so that the user can accurately set the balance temperature range of the valve according to the specific working conditions, and ensure that the cooling flow of each branch matches the heat dissipation requirements of the component. Through the scale, the user can intuitively adjust and monitor the temperature setting value of the temperature control valve to adapt it to the working temperature requirements of different components, thereby achieving personalized cooling optimization.

[0040] The valve body forms an opening and closing ring corresponding to the position of the valve core in the flow channel, and a sealing step and a through hole are formed in the opening and closing ring. The sealing step is used to cooperate with the valve body, and the diameter of the through hole is smaller than the diameter of the valve body. The purpose of this setting is to improve the sealing performance and flow adjustment accuracy of the self-operated temperature control valve 6. The sealing step is used to cooperate closely with the valve core to ensure that the flow channel can effectively block the flow of coolant when the valve core is closed to avoid leakage, thereby improving the sealing performance and cooling efficiency of the system.

[0041] Optionally, the self-operated temperature control valve 6 of this solution can be attached Figure 4 The electric temperature control valve 10 is replaced by the electric temperature control valve 10 in the embodiment. The electric temperature control valve 10 is controlled by a controller, and its cost is higher than that of the self-operated temperature control valve 6. The cost of using it in a system with many branches will increase a lot, but it has high control accuracy and can be used in systems that require precise control. The first electric drive water pump 1 of this scheme uses a PWM signal to adjust the duty cycle to control the speed, which can be used with an additional Figure 4 The constant power mechanical water pump 9 and the electric regulating valve 20 are used to replace the water pump to achieve flow regulation.

[0042] The first electric drive water pump 1 circuit and the second electric drive water pump 1 circuit are both connected with a pressure sensor 2 for detecting the outlet water pressure of the electric drive water pump 1. The purpose of connecting the pressure sensor 2 is to monitor the water pressure at the outlet of the electric drive water pump 1 in real time to ensure that the flow and head of the cooling system always meet the heat dissipation requirements of each branch. Through the pressure sensor 2, the actual working state of the water pump can be accurately detected. When the water pressure is lower than the required head, the control system can increase the PWM signal duty cycle, increase the water pump speed, and increase the head to meet the circulation requirements; when the water pressure is higher than the required head, the water pump speed can be reduced to reduce energy consumption and avoid overheating caused by power overflow. Such a design can not only dynamically adjust the output of the water pump and optimize the operating efficiency of the cooling system, but also prevent the water pump from shortening its service life due to overload or no-load operation.

[0043] The flow regulating loop of the cotton picker cooling system also includes an air cooler 7 arranged on the loop, and an expansion pot 8 is connected in parallel to the air cooler 7. The expansion pot 8 is used to accommodate the expansion of the system's coolant, stabilize the system pressure, and remove the air released by the water during the heating process. The air cooler 7 quickly dissipates the heat in the coolant through forced ventilation, thereby reducing the coolant temperature and ensuring the overall heat dissipation efficiency of the cooling system; the expansion pot 8 works in parallel with the air cooler 7 to accommodate the excess liquid generated by the expansion of the coolant due to heat, and replenishes the liquid when the coolant is cooled and contracted, thereby ensuring the dynamic balance of the amount of coolant in the system. The expansion pot 8 also has an exhaust function, which can avoid the generation of gas blockage by releasing gas when the coolant is heated, and prevent the problem of pressure fluctuation or cooling efficiency reduction in the pipeline. The advantage of this design is that it effectively avoids the impact of the expansion or contraction of the coolant on the system pressure, maintains the stability of the pressure of the cooling circuit, and prolongs the service life of the equipment; at the same time, the air in the coolant is eliminated through the gas exhaust function, thereby improving the smoothness of the coolant circulation and the cooling effect.

[0044] During long-term use, the coolant may be polluted by the external environment, or the corrosion and aging of the internal materials of the cooling system may produce sediment and particles. If these impurities are not removed in time, they may cause the following problems: pipeline blockage, affecting the circulation of the coolant; damage to precision parts such as water pumps and valves, shortening their service life; reducing the heat exchange efficiency of the radiator, affecting the overall heat dissipation performance of the system. By installing a coolant filter 5 in the cooling circuit, these impurities can be effectively captured to ensure the cleanliness of the coolant and the normal operation of the circulation system.

[0045] Reference Figure 3 , the control method of the cooling system of the cotton picker comprises the following steps:

[0046] S100, when the motor is started, the electric drive water pump 1 operates at an initial speed. At this time, the radiator does not work, that is, the cooling system temporarily does not have a cooling effect, so that the motor and the controller can quickly heat up to their preset working temperature.

[0047] Specifically, S100 includes the following steps:

[0048] Electric drive water pump 1 initial speed setting: When the cotton picker starts, the electric drive water pump 1 in the cooling system receives a preset signal through the controller and works at a lower initial speed. This speed is usually set by the system program, the purpose is to let the coolant circulate in the system at a slower speed, to ensure that only a small amount of coolant flows, and reduce the heat dissipation effect.

[0049] Turn off the radiator: At this time, the radiator in the cooling system (such as the air cooler 7) remains in a closed state, and its fan does not run. The start signal of the radiator is locked through the control logic, so that it does not participate in the work at the initial stage of the system. This ensures that the coolant will not be cooled quickly due to the action of the radiator.

[0050] Limited circulation of flow: In this stage, although the coolant circulates in the system in a limited manner, the cooling effect is greatly limited due to the closure of the radiator. As a result, the heat of the motor and controller in the initial stage can accumulate quickly, causing the temperature of the equipment to rise rapidly.

[0051] Temperature monitoring and judgment: The temperature sensor 3 in the cooling system monitors the temperature of the motor and the controller in real time. When the temperature gradually rises and approaches the preset optimal operating temperature range (for example, 45°C), the system begins to prepare to enter the normal cooling mode.

[0052] Switch to normal working state: When the temperature of a motor or controller reaches the set value, the radiator starts, the cooling system enters the normal operating stage, and begins to dissipate heat effectively.

[0053] The purpose of this step design is to quickly reach the ideal operating temperature of the motor and controller when the equipment is initially running. Running the motor and controller at a lower temperature will reduce efficiency and may affect performance and life, but this initial control strategy can avoid this problem and ensure that the equipment enters an efficient operating state in the shortest possible time, while reducing energy consumption and resource waste.

[0054] S200, when it is detected that the temperature of a motor or controller is greater than 45°C, the radiator is started and the cooling system begins to work; the balance temperature of the self-operated temperature control valve 6 of each branch is set according to respective requirements.

[0055] Specifically, S200 includes the following steps:

[0056] Temperature detection: The temperature sensors 3 in the cooling system monitor the operating temperature of all motors and controllers in real time. These sensors are arranged near key components and transmit temperature data to the system controller.

[0057] Temperature threshold determination: The controller receives data from the temperature sensor 3 and determines whether the temperature of any motor or controller exceeds 45°C (preset threshold). If no device reaches 45°C, the radiator remains off and the system continues to maintain the initial low-speed cycle. If the temperature of a device exceeds 45°C, a signal to start the radiator is triggered.

[0058] Start the radiator: When the trigger signal is sent, the radiator (such as the air cooler 7) starts to work. The fan of the air cooler 7 adjusts the speed through the controller to absorb the heat in the coolant and reduce its temperature, thereby starting to dissipate heat comprehensively.

[0059] The self-operated temperature control valve 6 starts to work: the self-operated temperature control valve 6 installed on each branch of the cooling system begins to adjust the flow according to their respective needs. These temperature control valves have been preset with different equilibrium temperatures when the system is set. For example, the generator branch may be set to a higher equilibrium temperature (such as 60°C), while the controller branch may be set to a lower equilibrium temperature (such as 50°C). When the temperature of the coolant exceeds the equilibrium temperature of each branch, the self-operated temperature control valve 6 will automatically increase the flow channel opening and increase the coolant flow to improve the heat dissipation efficiency; when the temperature drops, the valve gradually closes and reduces the flow to prevent overcooling.

[0060] Dynamic balanced cooling: The radiator and the self-operated temperature control valve 6 work together to dynamically adjust the coolant flow and cooling intensity according to the real-time temperature requirements of each branch to ensure that each device is always within the optimal operating temperature range.

[0061] Continuous monitoring and adjustment: The system continuously monitors the temperature changes of the equipment. If the temperature returns to below the threshold (such as below 45°C), the system may reduce the radiator speed or gradually close part of the flow; if the temperature continues to rise, the radiator and temperature control valve will further increase the cooling intensity.

[0062] S300, in order to avoid overheating caused by power overflow of the electric drive water pump 1, the total water resistance of the circuit of the first electric drive water pump 1 is calculated to ensure that the output head of the first electric drive water pump 1 is greater than the total water resistance of the circuit, so as to meet the circulation demand of the cooling system and avoid power overflow; the total water resistance of the circuit of the second electric drive water pump 1 is calculated to ensure that the output head of the second electric drive water pump 1 is greater than the total water resistance of the circuit, so as to meet the circulation demand of the cooling system and avoid power overflow.

[0063] Specifically, S300 includes the following steps:

[0064] Determine the cooling circuit parameters: collect and confirm the physical parameters of the first electric drive water pump 1 and the second electric drive water pump 1 circuit, including: the pipe length and diameter of each branch, the water resistance coefficient of the components in each branch (such as valves, self-operated temperature control valves 6, motors and controllers, etc.), and the fluid properties of the coolant (such as viscosity and density).

[0065] Calculate the total water resistance: Use the fluid mechanics formula to calculate the water resistance of each branch, and combine the resistance relationship of the branches in parallel or series into the total water resistance of the overall circuit.

[0066] The formula generally takes the following form: For the series part: total water resistance Rtotal = R1 + R2 + R3 + ...; For the parallel part: total water resistance Rtotal = 1 / (1 / R1 + 1 / R2 + 1 / R3 + ...) By combining these calculations, the total water resistance value of the first and second electric drive water pump 1 circuits is obtained.

[0067] Matching the water pump head requirement: According to the total water resistance calculation result, determine the minimum head H requirement of the first electric drive water pump 1 and the second electric drive water pump 1, so as to ensure that the output head of the water pump is sufficient to overcome the total water resistance of the circuit and meet the coolant circulation requirement.

[0068] Set the pump head target: Based on the head calculation, set the pump output head slightly higher than the target value of the total water resistance of the circuit. Htarget = Hdemand + ΔH, where ΔH is a safety margin to cope with possible changes in operating conditions.

[0069] Pump operation debugging and calibration: Use pressure sensor 2 to monitor the real-time water pressure at the pump outlet, and detect the actual head in combination with the system flow. If the actual head is found to be insufficient to meet the circuit requirements, the system will increase the pump speed by increasing the PWM duty cycle, thereby increasing the head and flow. If the actual head is too high, the system will reduce the PWM duty cycle and reduce the pump speed to save energy.

[0070] Applied to two water pumps in steps: First electric drive water pump 1 circuit: Priority calculation and debugging, used to cool high-load equipment such as generators, travel motors, cotton picking head motors, etc. Second electric drive water pump 1 circuit: Subsequently adjusted, used to cool controllers, fan motors, hydraulic pump motors, etc.

[0071] Continuous monitoring and dynamic adjustment: The system dynamically adjusts the output head of the water pump through real-time data from pressure sensor 2 and temperature sensor 3 to ensure that the circuit water resistance requirements are always met to avoid power overflow or shortage.

[0072] S400, the outlet of the electric drive water pump 1 is provided with a pressure sensor 2. When it is monitored that the outlet pressure of the water pump is smaller than the required head, the PWM duty cycle is increased and the water pump speed is increased, that is, the output head is increased; when it is monitored that the outlet pressure is larger than the required head, the PWM duty cycle is reduced and the water pump speed is reduced.

[0073] Specifically, S400 includes the following steps:

[0074] Pressure sensor 2 monitors the outlet pressure of the water pump in real time: A pressure sensor 2 is installed at the outlet of each electric drive water pump 1 to monitor the outlet pressure data of the water pump in real time. These sensors convert the collected pressure signals into electrical signals and transmit them to the system controller.

[0075] Calculate required head: The system determines the head required under the current working conditions based on the previously calculated total water resistance of the circuit.

[0076] Comparison of actual pressure with required head: The system controller compares the actual outlet pressure value Pactual provided by the pressure sensor 2 with the required head in real time.

[0077] Determine whether the water pump speed needs to be adjusted: When the outlet pressure is lower than the required head: If P_actual < H_required, it indicates that the head of the water pump is insufficient, and the coolant flow may not meet the circulation requirements. When the outlet pressure is higher than the required head: If P_actual > H_required, it indicates that the head of the water pump is too high, causing unnecessary power consumption or potential overheating problems.

[0078] Adjust the water pump speed through the PWM signal: Increase the PWM duty cycle: When the actual pressure is lower than the required head, the system will increase the PWM signal duty cycle of the water pump, increase the speed of the water pump, thereby increasing the output head and coolant flow of the water pump. Decrease the PWM duty cycle: When the actual pressure is higher than the required head, the system will decrease the PWM signal duty cycle, reduce the water pump speed, lower the head and flow rate, and avoid energy consumption waste and overheating.

[0079] Real-time feedback and dynamic balance: Through the continuous monitoring of the pressure sensor 2 and the real-time adjustment of the controller, the system maintains the dynamic balance between the output head of the water pump and the required head within each cycle. This feedback mechanism ensures that the coolant can maintain a stable flow rate in all branches.

[0080] Priority of adjustment and optimization: If the pressure is too low, prioritize ensuring that the head reaches the requirement to avoid insufficient cooling. If the pressure is too high, aim to save energy consumption and optimize the head output.

[0081] The flow regulation loop of the cooling system of the present invention can automatically adjust the loop flow according to the heat dissipation requirements under different working conditions, enabling each motor and controller to work within an optimal temperature range; these components are connected in series and parallel according to the cooling requirements of different motors and controllers, with a wide application range and flexible connection solutions; the flow regulation process is fully automatic without manual adjustment, with high reliability; the output flow of the electric drive water pump 1 automatically adjusts according to the cooling requirements, avoiding power overflow and extending the working life of the water pump.

[0082] The above are only the preferred embodiments of the present invention and are not used to limit the present invention. For those skilled in the art, the present invention can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. The flow regulating circuit of the cotton picker cooling system is characterized by: The invention comprises a first electric-driven water pump (1) circuit and a second electric-driven water pump (1) circuit connected in parallel, wherein the first electric-driven water pump (1) circuit and the second electric-driven water pump (1) circuit each comprise a plurality of branches, the heat-generating components of the cotton picker are grouped according to the required cooling flow rate, and the heat-generating components of different groups are connected to different branches, and each branch is provided with a self-operated temperature control valve (6), and each self-operated temperature control valve (6) controls the cooling flow rate through the valve body according to the cooling flow rate required by the heat-generating component on the corresponding branch.

2. The flow regulating circuit of the cooling system of the cotton picker according to claim 1, characterized in that: The first electric-driven water pump (1) comprises a first branch, a second branch and a third branch, the heat-generating element connected to the first branch comprises a generator and a generator controller, the heat-generating element connected to the second branch comprises a left front travel motor and a right front travel motor, and the heat-generating element connected to the third branch comprises a left cotton picking head motor and a right cotton picking head motor.

3. The flow regulating circuit of the cooling system of the cotton picker according to claim 2, characterized in that: The second electric drive water pump (1) circuit comprises a fourth branch, a fifth branch and a sixth branch, the heat generating element connected to the fourth branch is a dual drive controller, the heat generating element connected to the fifth branch is a fan motor and a single drive controller of the fan motor, and the heat generating element connected to the sixth branch is a hydraulic pump motor and a rear travel motor.

4. The flow regulating circuit of the cooling system of the cotton picker according to claim 1, characterized in that: The self-operated temperature control valve (6) comprises a valve body, a valve core and a temperature control component. The valve core is movably arranged in a flow channel in the valve body. The temperature control component comprises a temperature sensing component and a driving component. The temperature sensing component is located in the coolant of the corresponding branch and drives the driving component to move according to the principle of thermal expansion and contraction. The driving component then drives the valve core to move, thereby changing the conduction area of ​​the valve core flow channel.

5. The flow regulating circuit of the cooling system of the cotton picker according to claim 4, characterized in that: The driving component includes a valve cover connected to the valve body and an adjusting spring arranged in the valve cover, the valve core is connected to the adjusting spring, and the temperature sensing component includes a temperature sensing bag, which is connected to the valve cover through a conduit. The temperature sensing bag contains liquid or gas so as to transfer the force generated by thermal expansion and contraction of the liquid or gas to the valve core through the conduit.

6. The flow regulating circuit of the cooling system of the cotton picker according to claim 5, characterized in that: The valve cover is provided with a temperature scale.

7. The flow regulating circuit of the cooling system of the cotton picker according to claim 6, characterized in that: The valve body is formed with an opening and closing ring corresponding to the position of the valve core in the flow channel, and a sealing step and a through hole are formed in the opening and closing ring. The sealing step is used to cooperate with the valve body, and the diameter of the through hole is smaller than the diameter of the valve body.

8. The flow regulating circuit of the cooling system of the cotton picker according to claim 7, characterized in that: The first electric water pump (1) circuit and the second electric water pump (1) circuit are both connected to a pressure sensor (2) for detecting the outlet water pressure of the electric water pump (1).

9. The flow regulating circuit of the cooling system of the cotton picker according to claim 8, characterized in that: The flow regulating loop of the cotton picker cooling system also includes an air cooler (7) arranged on the loop, and an expansion pot (8) is connected in parallel to the air cooler (7). The expansion pot (8) is used to accommodate the expansion of the system's coolant, stabilize the system pressure, and remove the air released by the water during the heating process.

10. A method for controlling a cooling system of a cotton picker, using the flow regulating circuit of the cooling system of a cotton picker according to any one of claims 1 to 9, characterized in that: The steps include: When the machine is started, the electric drive water pump (1) operates at an initial speed, and the radiator does not work at this time, that is, the cooling system temporarily does not have a cooling effect, so that the motor and the controller can quickly heat up to their preset working temperature; When it is detected that the temperature of a motor or controller is greater than 45°C, the radiator is started and the cooling system starts to work; the self-operated temperature control valve (6) of each branch is set according to the respective requirements; In order to avoid overheating caused by power overflow of the electric drive water pump (1), the total water resistance of the circuit of the first electric drive water pump (1) is calculated to ensure that the output head of the first electric drive water pump (1) is greater than the total water resistance of the circuit, so as to meet the circulation demand of the cooling system and avoid power overflow; the total water resistance of the circuit of the second electric drive water pump (1) is calculated to ensure that the output head of the second electric drive water pump (1) is greater than the total water resistance of the circuit, so as to meet the circulation demand of the cooling system and avoid power overflow; The outlet of the electric drive water pump (1) is provided with a pressure sensor (2). When it is detected that the outlet pressure of the water pump is smaller than the required head, the PWM duty cycle is increased and the water pump speed is increased, that is, the output head is increased; when it is detected that the outlet pressure is larger than the required head, the PWM duty cycle is reduced and the water pump speed is reduced.

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