A method for controlling the filling and emptying of coolant

Abstract

The present invention discloses a method for controlling the filling and emptying of coolant. Through information interaction between a user and a vehicle controller, the EMS recognizes the user's behavior of filling coolant, and controls the water pump module and the temperature control module to ignore the demand for rapid heat-up in a short period of time during this driving cycle, and acts according to the coolant filling and emptying strategy to empty the entire cooling system to ensure that the coolant can be successfully filled. Specifically, the method includes the following steps: judging the feasibility of the coolant filling and emptying strategy, EMS identifying the user setting operation, EMS judging the type of water pump, the water pump module and the temperature control module executing the coolant filling and emptying strategy, and judging whether the coolant filling and emptying strategy is successfully terminated. The present invention avoids the situation where the coolant filling fails due to the characteristics of the electrified cooling system, resulting in insufficient subsequent engine cooling, or false alarm of the electronic water pump failure.

Description

Technical Field

[0001] The invention relates to the technical field of engines, and in particular to a method for controlling the filling and emptying of coolant. Background Art

[0002] The cooling system solutions currently used in the whole vehicle on the market are usually mechanical water pump + thermostat, in which the thermostat is used to adjust the two branches of the radiator large cycle and bypass small cycle. The thermostat is generally designed to gradually open the large cycle when it reaches 80-90℃, allowing the flow to enter the radiator for heat dissipation. In the conventional solution, neither the mechanical water pump nor the thermostat can be actively controlled, but because the thermostat can at least ensure that the small cycle is always open in the cold state, the structure of the entire cooling system is connected. When the coolant is added, the coolant can flow to various positions in the system. In addition, the mechanical water pump is driven by the engine. When the engine is working, the mechanical water pump will work. It will not stop working due to lack of water in the system or the presence of bubbles in some parts, and will not stop working due to dry running in a short period of time.

[0003] Therefore, when the manufacturer vacuums and fills the system before leaving the factory, or when after-sales service or users fill in the coolant by themselves, no special operation is required. Just start the engine for 3-5 minutes after filling, stir the coolant with a mechanical water pump to allow the air and liquid inside the system to be fully mixed, and then circulate to the expansion kettle and discharge it from the expansion kettle.

[0004] However, after the cooling system was electrified, the mechanical water pump and thermostat were replaced by an electronic water pump and temperature control module (electronically controlled ball valve), and a series of problems emerged. For example, the electronic water pump is decoupled from the engine speed. When the engine is cold-started, in order to achieve rapid warm-up, the electronic water pump often does not work, or only works in a small amount, and cannot fully stir the coolant and air. And because the upper part of the volute water chamber is often difficult to fill with water, that is, the air cannot be completely discharged in the initial state, at this time, the electronic water pump is forced to start. Because the water chamber is not full and the load is insufficient, at the same speed, the electronic water pump cannot reach the required power, and it is easy to be judged by the controller as dry running, thereby forcibly stopping work. In this state, the electronic water pump is actually a false alarm fault, but it will not be able to continue the filling and emptying process, nor can it continue to start the engine. In addition, during the cold start process of the engine, the temperature control module will usually adjust the opening to the minimum value, or even completely close it, and completely close the small circulation. At this time, the engine's cooling system branch is forcibly cut off, and the coolant cannot flow to every area after entering the engine. The liquid level in the expansion kettle is observed to be full, but in fact the inside of the engine is not full at all, which is prone to insufficient cooling in the subsequent working process.

[0005] The common solution on the market for the above problems is to vacuum and fill the system. After completely extracting the air from the system, inject coolant. At this time, the coolant can flow to various locations in the entire system under the action of the pressure difference and fill each interval. Vacuuming requires specific occasions and tools. However, vacuuming generally uses the Bernoulli effect. First, high-pressure gas is required. When the gas flow rate is high, the internal static pressure drops. At this time, a pressure difference occurs with the cooling system, and the air inside the system will be sucked out automatically, creating a vacuum inside the system. However, whether it is high-pressure gas or the corresponding vacuum equipment, it is difficult for users to obtain it. Coolant filling itself is a relatively routine and simple behavior. It is not appropriate to require users to obtain high-value and difficult equipment. Summary of the invention

[0006] In view of this, the present invention provides a coolant filling and emptying control method, which avoids the failure of coolant filling due to the characteristics of the electrified cooling system, resulting in insufficient subsequent engine cooling, or false alarm of electronic water pump failure.

[0007] A coolant filling and emptying control method provided by the present invention includes: judging the feasibility of a coolant filling and emptying strategy; if it is judged that the coolant filling and emptying strategy can be executed, further confirming the execution intention of the coolant filling and emptying strategy; if it is confirmed that the coolant filling and emptying strategy needs to be executed, then judging the type of water pump; then controlling the water pump module and the temperature control module to execute the coolant filling and emptying strategy; after the water pump module and the temperature control module have completed the execution of the coolant filling and emptying strategy, judging whether the coolant filling and emptying strategy has been successfully completed.

[0008] Furthermore, judging the feasibility of the coolant filling and emptying strategy includes: preliminarily judging the feasibility of the coolant filling and emptying strategy; and further judging whether the coolant filling and emptying strategy is indeed feasible.

[0009] Furthermore, the feasibility of the coolant filling and emptying strategy is preliminarily judged including: whether the vehicle is powered on; whether the hood is open; whether the expansion kettle cover is open; and whether the current water temperature is lower than the filling threshold. If all four conditions are met, it is preliminarily judged that the coolant filling and emptying strategy is feasible.

[0010] Further, judging whether the coolant filling and emptying strategy is indeed feasible includes: continuing to judge whether the current vehicle speed is equal to 0km / h, whether the current gear is in P gear, and whether the engine speed is equal to 0r / min. If so, it is determined that the coolant filling and emptying strategy is indeed feasible.

[0011] Furthermore, confirming the execution intention of the coolant filling and emptying strategy includes: determining whether the user steps on the brake pedal and the accelerator pedal to the bottom with both feet at the same time; and determining whether the user turns the steering wheel in one direction to the end dead point.

[0012] Furthermore, confirming the execution intention of the coolant filling and emptying strategy also includes: determining whether the user turns the steering wheel to the end dead point in another direction.

[0013] Furthermore, after confirming the need to execute the coolant filling and emptying strategy, it also includes: judging the type of water pump; after completing the water pump type judgment, judging the corresponding subsequent filling execution conditions according to the water pump type judgment result, and controlling the coolant filling and emptying strategy of the water pump module and the temperature control module after the corresponding filling execution conditions are met.

[0014] Furthermore, when judging the type of water pump, if the water pump is an electronic water pump, it is necessary to further judge the current battery status: whether the battery voltage is higher than the undervoltage threshold, whether the high voltage power is higher than the low power threshold. If so, the coolant filling and emptying strategy is started, if not, the filling process is ended and a prompt is given; if the water pump is a mechanical water pump, within the set time, further judge whether the engine can be successfully started and whether the engine speed is within a reasonable range. If both are true, the coolant filling and emptying strategy is started, if not, the filling process is ended and a prompt is given.

[0015] Furthermore, in executing the coolant filling and emptying strategy, if the water pump is an electronic water pump, it is necessary to determine whether the electronic water pump filling state speed and filling state time reach the set value, and determine whether the temperature control module filling state opening and filling state time reach the set value. If both reach the set value, the coolant filling and emptying strategy is executed; if the water pump is a mechanical water pump, it is necessary to determine whether the temperature control module filling state opening and filling state time reach the set value. If both reach the set value, the coolant filling and emptying strategy is executed.

[0016] Furthermore, when judging whether the coolant filling and emptying strategy is successfully completed, if the water pump is an electronic water pump, judge again whether the electronic water pump filling state speed, filling state time and the temperature control module filling state opening and filling state time all reach the set values. If so, the coolant filling and emptying strategy is successfully completed; when the water pump is an electronic water pump, judge again whether the temperature control module filling opening and filling state time all reach the set values. If so, the coolant filling and emptying strategy is successfully completed.

[0017] Furthermore, it also includes user detection, specifically including: the user observes the liquid level of the expansion kettle. If the liquid level is lowered, it is necessary to appropriately add liquid to the appropriate level and perform a secondary check; if the liquid level still remains at the upper scale line, it means that the interior has been completely exhausted, the cooling system is filled with coolant, and the filling process is completed.

[0018] Compared with the existing technology, the present invention has the following beneficial technical effects:

[0019] A coolant filling and emptying control method provided by the present invention enables the engine control system to recognize the user's behavior of filling coolant through information interaction between the user and the vehicle controller, and controls the water pump module and the temperature control module to ignore the demand for rapid engine warm-up within a short period of time in this driving cycle, and acts according to the coolant filling and emptying strategy, thereby avoiding the failure of coolant filling due to the characteristics of the electrified cooling system, resulting in insufficient subsequent engine cooling, or false alarm of a water pump module fault, ensuring that the user can successfully complete the filling behavior in one operation, thereby ensuring the subsequent safe operation of the whole vehicle. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 The present invention is a flow chart of a coolant filling and emptying control method. DETAILED DESCRIPTION

[0021] The specific implementation of the present invention is further described in detail below in conjunction with the accompanying drawings and examples. The following examples are used to illustrate the present invention, but are not intended to limit the scope of the present invention.

[0022] In the description of the present invention, it should be noted that the orientation or position relationship indicated in the description is based on the orientation or position relationship shown in the accompanying drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0023] Please refer to Figure 1 The present invention provides a coolant filling and emptying control method, which enables the EMS to recognize the user's intention to fill the coolant through information interaction between the user and the vehicle controller, and controls the water pump module and the temperature control module to ignore the rapid heat-up demand in a short time of this driving cycle, and to act according to the coolant filling and emptying strategy to empty the entire cooling system to ensure that the coolant can be successfully filled, including the following steps:

[0024] S1, preliminarily determine the feasibility of the coolant filling and emptying strategy.

[0025] Because the water temperature is too high when the engine is working, when the engine is started or the water pump is working, the liquid may splash to the outside and cause burns. Therefore, it is generally recommended to refill in a cold state. Therefore, it is necessary to determine whether the water temperature is below the threshold. In order to discharge the gas during emptying, the expansion kettle cover needs to be opened. In order to facilitate observation and secondary refilling, the engine hood also needs to be kept open. After emptying, the user will further confirm the liquid level change and determine whether to continue secondary refilling. The emptying action will be completed by the actuator, so the user needs to power on the entire vehicle.

[0026] Based on the above reasons, EMS needs to make a preliminary judgment on the feasibility of the coolant filling and emptying strategy. First, three conditions are judged: a. Whether the vehicle is powered on. If it is powered on but not started, Bit_on = 1 (the vehicle is powered on), otherwise Bit_on = 0 (the vehicle is powered off); b. Whether the hood is open, the hood sensor directly reads the signal. If the hood is open, Bit_hood1 = 1 (the hood is open), otherwise Bit_hood1 = 0 (the hood is closed); c. Whether the expansion kettle cover is open, the expansion kettle cover sensor directly reads the signal. Receive the read signal. If the expansion kettle cover is open, Bit_hood2 = 1 (expansion kettle cover is open), otherwise Bit_hood2 = 0 (expansion kettle cover is closed); d. Is the current water temperature lower than the filling threshold? If the above four conditions are met: Bit_on = 1, Bit_hood1 = 1, Bit_hood2 = 1 and the previous water temperature is lower than the filling threshold, it is preliminarily considered that the coolant filling and emptying strategy is feasible, and the next step is entered, and the process status bit of the coolant filling and emptying strategy is marked as Bit_s1 = 1 (preliminary judgment is feasible). In this process, if Bit_on = 0 (the whole vehicle is powered off), or Bit_hood1 = 0 or Bit_hood2 = 0 (the engine hood or expansion kettle cover is closed), or the water temperature is high and exceeds the threshold, it is considered to be non-cold filling, and there is a risk. At this time, the status bit of the coolant filling and emptying strategy process is marked as Bit_s1 = 0 (the filling process is completed). Since opening the hood when the car is cold is a routine maintenance behavior and is not necessarily caused by adding coolant, this step is only for initial judgment and no prompts will be given to the instrument.

[0027] S2, when the coolant filling and emptying strategy is initially judged to be feasible, further judging whether the coolant filling and emptying strategy is indeed feasible.

[0028] Since the user operation needs to be identified later, but the user's operation behavior must be performed under safe conditions, it is necessary to determine whether the current vehicle speed is equal to 0km / h, that is, to ensure that the vehicle is static, whether the current gear is in P gear, it must be in parking state to avoid rolling back, and whether the engine speed is equal to 0r / min. This step needs to ensure that the subsequent behavior is absolutely safe. The above conditions are in an "and" relationship. When all are met, it is determined that the coolant filling and emptying strategy is indeed feasible. At this time, the process status of the coolant filling and emptying strategy is changed from Bit_s1=1 (preliminary judgment is feasible) to Bit_s2=1 (indeed feasible), and the filling display status bit is marked as Bit_add_dis=1. At this time, the instrument starts to display the filling status and pops up the message "Coolant emptying step in progress". The system officially enters the filling and emptying strategy condition identification process. When the filling display status bit Bit_add_dis=0 is the normal vehicle startup state, the instrument does not have any prompts.

[0029] S3, after determining that the coolant filling and emptying strategy is indeed feasible, the EMS needs to further confirm the execution intention of the coolant filling and emptying strategy by identifying the set user operation.

[0030] EMS needs to interact with the user through a series of special operations performed by the user, which are then identified by EMS. When these operations are identified, it is confirmed that the coolant filling and emptying strategy needs to be executed. In order to avoid system misjudgment, the user's operation behavior needs to be significantly different from the normal behavior, and several steps need to be connected to each other. The more steps, the more difficult it is to misjudge. There must be a corresponding time constraint between each step. If the countdown exceeds, it is assumed that the waiting time is too long. The user is unwilling to continue, and the system automatically exits the coolant filling and emptying steps and switches to the normal strategy state.

[0031] Specifically, the system needs to identify the following three setting operations performed by the user:

[0032] S3.1, determining whether the user steps on the brake pedal and the accelerator pedal to the bottom with both feet at the same time.

[0033] On the basis that the coolant filling and emptying strategy process is in the state of Bit_s2=1 (it is indeed feasible), the user can start the confirmation operation. According to the pre-set confirmation operation action, the user is first required to step on the brake pedal and the accelerator pedal to the bottom with both feet. At this time, the EMS determines whether the brake pedal stroke and the accelerator pedal stroke are both higher than the corresponding threshold value (considering that different users have different strengths and may not be able to step on the bottom, the threshold values ​​are set to "deep stepping", such as 90-95% of the stroke, not 100%). If the brake pedal stroke and the accelerator pedal stroke are both higher than the corresponding threshold value, it means that the brake pedal and the accelerator pedal are both stepped to the bottom. At this time, the process state of the coolant filling and emptying strategy is changed from Bit_s2=1 (it is indeed feasible) to Bit_s3=1 (both pedals have been stepped to the bottom). After that, the countdown t_count_s2 starts (that is, it is necessary to leave enough time for the user, but it should not be too long, generally set to 10-30s), waiting for the next step. If the user has not activated the next step at the end of the countdown t_count_s2, or the process status of the coolant filling and draining strategy becomes Bit_s1=0 (preliminary judgment is not feasible) due to closing the hood, starting the engine, etc. during this process, or the car moves abnormally, resulting in the vehicle speed not being equal to 0km / h, or the gear is switched and is no longer in P gear, resulting in Bit_s2=0 (really not feasible), then the filling display status bit is marked as Bit_add_dis=2, indicating exiting the filling, and the instrument pops up the message "Coolant draining step failed".

[0034] S3.2, after the double pedals are pressed to the bottom, further determine whether the user has turned the steering wheel left to the dead point.

[0035] When Bit_s3=1 (both pedals have been stepped on to the bottom), EMS needs to double-confirm the user, and requires the user to turn the steering wheel to the left to the end dead center. During the countdown t_count_s2, EMS continues to confirm the steering wheel angle. EMS obtains the steering wheel angle signal from the vehicle CAN network to confirm that the steering wheel's left turn travel is not less than the maximum left turn angle threshold (to avoid errors in user actions, it is not actually necessary to turn the steering wheel to the dead center, but it is required to turn the steering wheel to the left at a full 90-95% angle. Therefore, the maximum left turn angle threshold is 90-95% of the maximum left turn to the dead center). The process status of the coolant filling and emptying strategy is set to Bit_s4=1 (the steering wheel has completed the left turn to the end dead center), and the countdown t_count_s3 is entered (that is, enough time needs to be left for the user). If the next step is not activated at the end of the countdown, or the process status of the coolant filling and emptying strategy becomes Bit_s1=0 (preliminary judgment is not feasible), or Bit_s2=0 (really not feasible), or Bit_s3=0 (double pedals are not stepped on to the bottom) due to various abnormalities, the process will be exited by default. At this time, the process status of the coolant filling and emptying strategy is set to Bit_s4=0 (steering wheel has not completed the left turn to the end dead point), the filling display status bit is marked as Bit_add_dis=2 (exit filling), and the instrument pops up the message "Coolant emptying step failed".

[0036] S3.3, based on the steering wheel having completed the left turn to the end dead point, further determine whether the user turns the steering wheel to the right to the end dead point.

[0037] As mentioned above, when the process status of the coolant filling and emptying strategy is Bit_s4=1 (the steering wheel has completed the left turn to the end dead point), the EMS continues to determine whether to enter the next step. At this time, the user holds the steering wheel and turns right until the steering wheel is at the end dead point. At this time, the EMS obtains the steering wheel angle signal from the vehicle CAN network and confirms that the right turn stroke of the steering wheel is not less than the maximum right turn angle threshold. The process status of the coolant filling and emptying strategy is set to Bit_s5=1 (the steering wheel has completed the right turn to the end dead point). At this time, the countdown t_count_s4 is entered (that is, sufficient time needs to be left for the user, but not too long, generally set to 10-30s), if the next step has not been activated at the end of the countdown, or due to any abnormality, the process status of the coolant filling and emptying strategy becomes Bit_s1=0 (preliminary judgment is not feasible), or Bit_s2=0 (really not feasible), or Bit_s3=0 (double pedals are not stepped on to the bottom), or Bit_s4=0 (the steering wheel has not completed the left turn to the end dead center), then the process status of the coolant filling and emptying strategy is set to Bit_s5=0 (the steering wheel has not completed the right turn to the end dead center), the filling display status bit is marked as Bit_add_dis=2 (exit filling), and the instrument pops up the message "Coolant emptying step failed".

[0038] S4: After further confirming the execution of the coolant filling and draining strategy, the EMS needs to determine the type of water pump.

[0039] When the process status of the coolant filling and emptying strategy is Bit_s5=1 (the steering wheel has completed the right turn to the end dead point), the EMS has fully confirmed the user behavior and needs to execute the coolant filling and emptying strategy, so the water pump module and the temperature control module can start to execute the coolant filling and emptying strategy. However, due to the variety of engine solutions, there are many situations such as mechanical water pump + temperature control module, electronic water pump + thermostat, and electronic water pump + temperature control module. The coolant filling and emptying strategy first requires the water pump to work, mix the air and coolant in the system evenly, and transport the air to the position of the expansion kettle. Since the expansion kettle is opened during this period and directly connected to the atmosphere, the internal gas can be discharged. For the electronic water pump, since its speed is decoupled from the engine, the operation can be performed without starting the engine. This is the preferred solution. For the mechanical water pump, since its speed is coupled with the engine, the engine must be started before the operation can be performed. However, the operation of the electronic water pump directly consumes battery energy. If the vehicle has not moved for a long time and the battery is low, the engine may not start. Therefore, the engine must be started for filling and emptying when the battery is low. Therefore, before the electronic water pump and temperature control module execute the coolant filling and emptying strategy, the EMS needs to determine the type of water pump when the process status of the coolant filling and emptying strategy is Bit_s5 = 1 (the steering wheel has completed the right turn to the end dead point).

[0040] EMS reads the status of the main cooling water pump of the engine preset in the early stage of design, and determines whether it is an electronic water pump or a mechanical water pump. If it is an electronic water pump, CWBit_ewp=1 (electronic water pump) is preset, and if it is a mechanical water pump, CWBit_ewp=0 (mechanical water pump) is preset. When CWBit_ewp=1 (electronic water pump) and the process status of the coolant filling and emptying strategy is Bit_s5=1 (the steering wheel has completed the right turn to the end dead point), EMS also needs to judge the current battery status. In the system of conventional fuel vehicles, only the 12V battery supplies power to the electronic water pump. Therefore, when the battery voltage is higher than the undervoltage threshold, the coolant filling and emptying execution process is directly entered. For hybrid vehicles, since the 12V battery is connected to the high-voltage battery, the 12V battery voltage must be higher than the undervoltage threshold, and the high-voltage battery power must be higher than the low power threshold; therefore, the judgment conditions of the battery status need to be pre-set according to the vehicle model. If the power condition is judged as yes, that is, the power is sufficient to support the operation of the electronic water pump, the system can enter the coolant filling and emptying strategy, and the EMS activates the electronic water pump and temperature control module in the cooling system, and sets the filling working state to Bit_vac1, indicating that the coolant filling and emptying strategy is started, and the electronic water pump and temperature control module are controlled to perform the filling action. If the battery voltage of the conventional vehicle model is not higher than the undervoltage threshold, or the hybrid vehicle model cannot meet the voltage and SOC of the 12V battery, the EMS waits to enter the next step, and the subsequent steps are the same as when CWBit_ewp=0 (mechanical water pump) and Bit_s5=1 (the steering wheel has completed the right turn to the end dead point).

[0041] When CWBit_ewp=0 (mechanical water pump) and Bit_s5=1 (the steering wheel has completed the right turn to the end dead point), EMS still needs to determine whether to enter the next step. At this time, the EMS system enters the countdown t_count_s5. The user needs to ignite and start the engine before the countdown ends (starting the engine to stabilize it at the idle level requires a certain process, generally 3-5s per time. In order to ensure that there are 2-3 start times to ensure successful start, the countdown t_count_s5 is generally set to 20-30s). During this process, EMS continues to determine whether the engine speed is within a reasonable range. If the engine speed is within the idle threshold ±100r / min range (idle speed generally fluctuates) before the countdown ends, the process status of the coolant filling and emptying strategy is set to Bit_s6=1 (complete water pump type judgment), and the filling working status is set to Bit_vac=1 (start coolant filling and emptying strategy), and sent to the electronic water pump and temperature control module control module. During this process, if the process status of the coolant filling and draining strategy changes to Bit_s1=0 (preliminary judgment is not feasible) or Bit_s2=0 (definitely not feasible) or Bit_s3=0 (double pedals are not pressed to the bottom) or Bit_s4=0 (steering wheel has not completed the left turn to the end dead center) or Bit_s5=0 (steering wheel has not completed the right turn to the end dead center), or when the countdown ends, Bit_s6=0 (water pump type judgment is not completed), the coolant filling display status bit will be set to Bit_add_dis=2 (exit filling), and the instrument will pop up the message "Coolant draining step failed".

[0042] S5, based on the determination of the water pump type, the water pump module and the temperature control module execute the coolant filling and draining strategy.

[0043] Since the actual emptying process generally requires the water pump to work at an appropriate speed (electronic water pumps can be adjusted, while mechanical water pumps are fixed speeds considering the engine idle speed) to drive the coolant flow, the temperature control module is required to be opened to a position where large and small cycles are staggered, or other positions that can ensure the connectivity of the entire system. Therefore, if the engine is designed with an electronic water pump, when CWBit_ewp=1 (electronic water pump) is preset, when the electronic water pump control module and the temperature control module control module receive Bit_vac=1 (starting the coolant filling and emptying strategy), they enter the corresponding coolant filling working state respectively, the electronic water pump queries the calibrated filling state speed and filling state time, and executes the calibrated filling state speed as the target speed, and the duration; the temperature control module control module queries the calibrated filling state opening and filling state time, and starts to execute the calibrated filling state opening as the target opening, and the duration. When the electronic water pump is at the set speed and the filling state time is met, a signal ewp_finish=1 is sent (the electronic water pump execution is completed), otherwise ewp_finish=0 (the electronic water pump execution is not completed); when the temperature control module is at the set opening and the working duration meets the filling state time, a signal TMM_finish=1 is sent (the temperature control module execution is completed), otherwise TMM_finish=0 (the temperature control module execution is not completed).

[0044] If the engine is designed as a mechanical water pump and CWBit_ewp=0 (mechanical water pump) is preset, the mechanical water pump will work freely with the engine ignition, and only the temperature control module will perform corresponding actions internally. When the working duration meets the filling state time at the set opening, a signal TMM_finish=1 (temperature control module execution is completed) is sent, otherwise TMM_finish=0 (temperature control module execution is not completed).

[0045] In the above steps, in a system with an electronic water pump, the engine does not need to be started for filling and emptying, and there is no risk. However, if the battery is low or the system is a mechanical water pump, the engine needs to be started. To ensure safety, the emptying process must remain idle throughout. If the engine speed exceeds the idle threshold of ±100r / min, the user may have performed a flameout operation or stepped on the accelerator to make the engine reach a high idle speed. In this process, to avoid accidents, the process status of the coolant filling and emptying strategy is set to Bit_s6=0 (water pump type judgment is not completed), the filling working status bit is set to Bit_vac=0, indicating that the coolant filling and emptying strategy is not started, the filling display status bit is set to Bit_add_dis=2 (exit filling), and the instrument pops up the message "Coolant emptying step failed".

[0046] S6, based on the water pump module and the temperature control module having completed the execution of the coolant filling and emptying strategy, determining whether the coolant filling and emptying strategy is successfully completed.

[0047] If the powertrain is designed with an electronic water pump, when CWBit_ewp=1 (electronic water pump) is preset, the EMS determines whether the electronic water pump execution completion signal ewp_finish and the temperature control module execution completion signal TMM_finish are equal to 1. If ewp_finish=1 (electronic water pump execution is completed) and TMM_finish=1 (temperature control module execution is completed), it means that the filling and emptying are completed. At this time, the process status of the coolant filling and emptying strategy is set to Bit_s7=1 (successful completion), otherwise Bit_s7=0 (unsuccessful completion); if CWBit_ewp=0 (mechanical water pump) is preset, the EMS only determines whether the temperature control module execution completion signal TMM_finish is equal to 1. If TMM_finish=1 (temperature control module execution is completed), it means that the filling and emptying are completed. At this time, the process status of the coolant filling and emptying strategy is set to Bit_s7=1 (successful completion), otherwise Bit_s7=0 (unsuccessful completion).

[0048] S7: After the coolant filling and draining strategy is successfully completed, the user is required to perform a test.

[0049] After the filling and emptying is successfully completed, the user needs to be prompted. After completing this step, the user observes the liquid level of the expansion kettle. If the liquid level drops, it means that air is indeed discharged from the inside, and the liquid needs to be properly added to the appropriate liquid level for a second check. If the liquid level still remains on the upper scale line, it means that the inside has been completely exhausted, the cooling system is filled with coolant, and the filling process is completed. At this time, the expansion kettle cover can be closed, the engine cover can be closed, and the normal state can be entered.

[0050] As mentioned above, in the above full emptying process, if the filling display status bit is Bit_add_dis=0 (normal state), the filling and emptying identification is not performed at this time, and the instrument does not make any special prompts. When the filling display status bit is Bit_add_dis=1 (the system officially enters the filling and emptying strategy condition identification process), it means that in the emptying judgment process, the instrument prompts "coolant emptying step is in progress". When the filling display status bit is Bit_add_dis=2 (exit filling), it means that a certain step in the process failed, then the instrument prompts "coolant emptying step failed" and lasts for a certain period of time. After the countdown ends, the filling display status bit becomes Bit_add_dis=0 (normal state), and the normal state is restored, waiting for the user to restart. When and only when the EMS sets the process status of the coolant filling and emptying strategy to Bit_s7=1 (successful completion), it means that the filling is successful. When Bit_s7=1 (successful completion), Bit_add_dis=0 (normal state) and the normal state is restored. When Bit_s7=1 (successfully completed), the instrument prompts "Coolant draining process completed" and lasts for a certain period of time. After the duration is over, the prompt disappears and the whole process is completed.

[0051] To summarize, the present invention provides a coolant filling and emptying control method, which enables the engine control system to recognize the user's behavior of filling coolant through information interaction between the user and the vehicle controller, and controls the water pump module and the temperature control module to ignore the rapid warm-up demand in a short period of time during this driving cycle, and acts according to the coolant filling and emptying strategy, thereby avoiding the failure of coolant filling due to the characteristics of the electrified cooling system, resulting in insufficient subsequent engine cooling, or false alarm of a water pump module fault, ensuring that the user can successfully complete the filling behavior in one operation, thereby ensuring the subsequent safe operation of the vehicle.

[0052] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A method for controlling the filling and emptying of a coolant, characterized in that: include: Determine the feasibility of coolant filling and draining strategies; If it is determined that the coolant filling and emptying strategy can be executed, the execution intention of the coolant filling and emptying strategy is further confirmed; If it is confirmed that the coolant filling and emptying strategy needs to be executed, the water pump module and the temperature control module are controlled to execute the coolant filling and emptying strategy; After the water pump module and the temperature control module have completed the coolant filling and emptying strategy, it is determined whether the coolant filling and emptying strategy has been successfully completed; Determine the type of water pump; After the water pump type is determined, the corresponding subsequent filling execution conditions are determined according to the water pump type determination result, and the water pump module and the temperature control module coolant filling and emptying strategies are controlled after the corresponding filling execution conditions are met; When judging the type of water pump, if the water pump is an electronic water pump, it is necessary to further judge the current battery status: whether the battery voltage is higher than the undervoltage threshold, whether the high voltage power is higher than the low power threshold, if so, the coolant filling and emptying strategy is started, if not, the filling process ends and a prompt is given; If the water pump is a mechanical water pump, within the set time, it is further determined whether the engine can be successfully started and whether the engine speed is within a reasonable range. If both are true, the coolant filling and emptying strategy is started. If not, the filling process ends and a prompt is given.

2. The coolant filling and emptying control method according to claim 1, characterized in that: The feasibility of the coolant filling and draining strategy includes: Preliminarily determine the feasibility of the coolant filling and emptying strategy; Further determine whether the coolant filling and draining strategy is indeed feasible.

3. The coolant filling and emptying control method according to claim 2, characterized in that: The feasibility of the coolant filling and emptying strategy is initially determined as follows: Determine whether the vehicle is powered on; Determine whether the hood is open; Determine whether the expansion kettle cover is open; Determine whether the current water temperature is lower than the filling threshold; If the above four conditions are met, it can be preliminarily judged that the coolant filling and draining strategy is feasible.

4. The coolant filling and emptying control method according to claim 2, characterized in that: Further judging whether the coolant filling and emptying strategy is indeed feasible includes: judging whether the current vehicle speed is equal to 0km / h, whether the current gear is in P gear, and whether the engine speed is equal to 0r / min. If so, it is determined that the coolant filling and emptying strategy is indeed feasible.

5. The coolant filling and emptying control method according to claim 1, characterized in that: Confirm that the execution intent of the coolant filling and emptying strategy includes: Determine whether the user presses the brake pedal and the accelerator pedal to the bottom with both feet at the same time; Determine whether the user turns the steering wheel to the dead point in one direction.

6. The coolant filling and emptying control method according to claim 5, characterized in that: Confirming the execution intention of the coolant filling and emptying strategy also includes: determining whether the user turns the steering wheel to the end dead point in another direction.

7. The coolant filling and emptying control method according to claim 1, characterized in that: In the execution of the coolant filling and emptying strategy, if the water pump is an electronic water pump, it is necessary to determine whether the electronic water pump filling state speed and filling state time have reached the set values, and determine whether the filling state opening and filling state time of the temperature control module have reached the set values. If both have reached the set values, the execution of the coolant filling and emptying strategy is completed; If the water pump is a mechanical water pump, it is necessary to determine whether the filling state opening and filling state time of the temperature control module reach the set values. If both reach the set values, the coolant filling and emptying strategy is executed.

8. The coolant filling and emptying control method according to claim 1, characterized in that: When judging whether the coolant filling and emptying strategy is successfully completed, if the water pump is an electronic water pump, it is judged again whether the electronic water pump filling state speed, filling state time and the temperature control module filling state opening and filling state time have reached the set values. If so, the coolant filling and emptying strategy is successfully completed; When the water pump is an electronic water pump, it is determined again whether the filling opening and filling state time of the temperature control module have reached the set values. If so, the coolant filling and emptying strategy is successfully completed.

9. The coolant filling and emptying control method according to claim 1, characterized in that: It also includes user detection, including: The user observes the liquid level in the expansion kettle. If the liquid level drops, it is necessary to add liquid to the appropriate level and perform a second check. If the liquid level still remains on the upper scale line, it means that the interior has been completely exhausted, the cooling system is filled with coolant, and the filling process is completed.

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