A crankcase ventilation system control method, crankcase, and vehicle

Abstract

This invention discloses a crankcase ventilation system control method, a crankcase, and a vehicle. The control method includes: initially determining whether the water vapor content is less than or equal to a preset water vapor content and the crankcase temperature is greater than a preset crankcase temperature. If not, it determines whether the intake manifold pressure is greater than a preset pressure value. If yes, it executes a solenoid valve opening control strategy and a crankcase gas heater opening strategy. It then determines again whether the water vapor content is less than or equal to a preset water vapor content and the crankcase temperature is greater than a preset crankcase temperature. If yes, it executes a solenoid valve closing control strategy and a crankcase gas heater closing strategy. Finally, it determines whether the engine is stopped. If the engine is not stopped, it returns to the initial determination step. This invention maintains the engine crankcase temperature and water vapor concentration within a reasonable range, reducing the risk of oil emulsification due to water in hydrogen combustion products, thereby preventing engine damage.

Description

Technical Field

[0001] The present invention relates to crankcase technology, and more particularly to a crankcase ventilation system control method, a crankcase, and a vehicle. Background Technology

[0002] Hydrogen, as a clean and new energy source, is being used more and more widely, especially in the field of hydrogen fuel cell vehicles, which has seen significant development.

[0003] However, while hydrogen as a vehicle fuel meets increasingly stringent emission regulations, it also presents new challenges to engines. Because piston rings cannot completely seal, combustion products from blow-by inevitably enter the crankcase. Furthermore, most hydrogen engines utilize the crankcase ventilation system found in gasoline engines, which cannot guarantee that water vapor levels in the crankcase remain below a certain concentration. Hydrogen combustion produces a significant amount of water. When this water vapor precipitates into the engine oil at certain temperatures and concentrations, it can cause oil emulsification, reducing the oil's protective function and potentially damaging the engine. Summary of the Invention

[0004] This invention provides a crankcase ventilation system control method, a crankcase, and a vehicle to reduce the water content in engine oil, prevent oil emulsification, and thus avoid engine damage.

[0005] In a first aspect, embodiments of the present invention provide a crankcase ventilation system control method, comprising:

[0006] Initially determine whether the conditions are met: water vapor content ≤ preset water vapor content, and crankcase temperature > preset crankcase temperature;

[0007] If not, determine whether the intake manifold pressure is greater than the preset pressure value;

[0008] If so, then execute the solenoid valve opening control strategy and the crankcase gas heater opening strategy.

[0009] The system then determines whether the conditions are met: water vapor content ≤ preset water vapor content, and crankcase temperature > preset crankcase temperature.

[0010] If so, then execute the solenoid valve shutdown control strategy and the crankcase gas heater shutdown strategy;

[0011] Determine if the engine has stopped;

[0012] If the engine is not stopped, return to the initial determination of whether the water vapor content is less than or equal to the preset water vapor content and the crankcase temperature is greater than the preset crankcase temperature.

[0013] Optionally, after determining whether the engine has stopped, the method further includes: if the engine has stopped, then terminating the control of the crankcase ventilation system.

[0014] Optionally, after the initial determination of whether the water vapor content is ≤ preset water vapor content and the crankcase temperature is > preset crankcase temperature, the method further includes: if so, terminating the control of the crankcase ventilation system.

[0015] Optionally, after determining again whether the water vapor content is less than or equal to the preset water vapor content and the crankcase temperature is greater than the preset crankcase temperature, the method further includes: if not, returning to the step of executing the solenoid valve opening control strategy and executing the crankcase gas heater opening strategy.

[0016] Optionally, after determining whether the intake manifold pressure is greater than the preset pressure value, the method further includes: if not, implementing the active oil-gas separator speed adjustment strategy to the first speed and implementing the crankcase gas heater activation strategy.

[0017] Optionally, after executing the active oil-gas separator speed adjustment to the first speed strategy and the crankcase gas heater activation strategy, the method further includes: determining again whether the water vapor content is less than or equal to the preset water vapor content and the crankcase temperature is greater than the preset crankcase temperature; if not, then returning to the steps of executing the active oil-gas separator speed adjustment to the first speed strategy and the crankcase gas heater activation strategy.

[0018] Optionally, after determining again whether the water vapor content is less than or equal to the preset water vapor content and the crankcase temperature is greater than the preset crankcase temperature, the method further includes: if so, then executing the active oil-gas separator speed adjustment strategy to the second speed and executing the crankcase gas heater shutdown strategy.

[0019] Optionally, after implementing the active oil-gas separator speed adjustment strategy to the second speed and the crankcase gas heater shutdown strategy, the method further includes:

[0020] Determine whether the engine has stopped;

[0021] If the engine stops, control of the crankcase ventilation system is terminated;

[0022] If the engine is not stopped, return to the initial determination of whether the water vapor content is less than or equal to the preset water vapor content and the crankcase temperature is greater than the preset crankcase temperature.

[0023] Secondly, embodiments of the present invention also provide a crankcase capable of executing any of the above-described crankcase ventilation system control methods.

[0024] Thirdly, embodiments of the present invention also provide a vehicle including the aforementioned crankcase.

[0025] The crankcase ventilation system control method provided in this embodiment of the invention includes: initially determining whether the water vapor content is ≤ preset water vapor content and the crankcase temperature is > preset crankcase temperature; if not, determining whether the intake manifold pressure is > preset pressure value; if yes, executing a solenoid valve opening control strategy and a crankcase gas heater opening strategy; again determining whether the water vapor content is ≤ preset water vapor content and the crankcase temperature is > preset crankcase temperature; if yes, executing a solenoid valve closing control strategy and a crankcase gas heater closing strategy; determining whether the engine is stopped; if the engine is not stopped, returning to the initial determination of whether the water vapor content is ≤ preset water vapor content and the crankcase temperature is > preset crankcase temperature. Through this method, appropriate strategies can be activated when the crankcase needs ventilation or heating, thereby preventing water vapor from precipitating in the engine oil, preventing oil emulsification, and thus preventing engine damage. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of a crankcase ventilation system provided in an embodiment of the present invention;

[0027] Figure 2 A logic diagram of a crankcase ventilation system control method provided in an embodiment of the present invention;

[0028] Figure 3 This is a logic diagram of another crankcase ventilation system control method provided in an embodiment of the present invention. Detailed Implementation

[0029] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, the accompanying drawings show only the parts relevant to the present invention, and not all of the structures.

[0030] At the current stage of technology, most hydrogen engines use the crankcase ventilation system of gasoline engines. The crankcase ventilation system control method provided in this embodiment of the invention can be applied to any type of crankcase ventilation system. For ease of understanding, the working process of a crankcase ventilation system will be given as an example below. Figure 1 This is a schematic diagram of a crankcase ventilation system provided in an embodiment of the present invention, with reference to... Figure 1Crankcase gas 2, after being separated by active oil-gas separator 9, enters the pipeline between air filter 7 and turbocharger 6, and re-participates in combustion through intake manifold 4; active oil-gas separator 9 can control crankcase pressure by adjusting speed, the higher the speed, the greater the negative pressure in crankcase, and the higher the gas exchange frequency in crankcase; water vapor content sensor 1 monitors the water vapor concentration in crankcase in real time; crankcase temperature sensor 10 monitors the temperature in crankcase in real time; intake air temperature and pressure sensor 5 monitors the gas pressure in intake manifold in real time; one-way valve 8 controls gas to flow only from air filter to engine through mechanical structure; solenoid valve 3 controls the gas flow between intake manifold and engine by vehicle resistance control unit (ECU); crankcase gas heater 11 is controlled by ECU to turn on and off to heat crankcase gas.

[0031] Figure 2 This is a logic diagram of a crankcase ventilation system control method provided in an embodiment of the present invention. Figure 3 This is a logic diagram of another crankcase ventilation system control method provided in an embodiment of the present invention, with reference to... Figure 2 and Figure 3 The present invention provides a crankcase ventilation system control method, comprising:

[0032] After the engine is started, the following operations can be performed.

[0033] S1: Initially determine whether the water vapor content is ≤ preset water vapor content K and the crankcase temperature is > preset crankcase temperature T.

[0034] The water vapor content and crankcase temperature can both be obtained through sensors in the crankcase ventilation system, and the preset water vapor content K and preset crankcase temperature T can be determined according to actual needs.

[0035] Optionally, if so, control of the crankcase ventilation system shall be terminated.

[0036] Since the water vapor content and crankcase temperature are both at normal levels, no action is required, and the control system of the crankcase ventilation system can be shut down.

[0037] S2: If not, determine whether the intake manifold pressure is greater than the preset pressure value.

[0038] The intake manifold pressure can be obtained from a sensor in the crankcase ventilation system, and the preset pressure value can be determined according to actual needs. For example, the preset pressure value can be 10 kPa.

[0039] S3: If so, then execute the solenoid valve opening control strategy and the crankcase gas heater opening strategy.

[0040] The opening and closing of the solenoid valve and crankcase gas heater can be controlled by the ECU. When the solenoid valve is opened, fresh air enters the crankcase from the intake manifold through the solenoid valve.

[0041] S4: Determine again whether the water vapor content is ≤ preset water vapor content K and the crankcase temperature is > preset crankcase temperature T.

[0042] Optional; if not, return to step S3.

[0043] S5: If so, execute the solenoid valve shutdown control strategy and the crankcase gas heater shutdown strategy.

[0044] S6: Determine if the engine has stopped.

[0045] If the engine does not stop, return to step S1.

[0046] Optionally, if the engine stops, control of the crankcase ventilation system is terminated.

[0047] After executing step S2, the process also includes: if not, executing the active oil-gas separator speed adjustment strategy to the first speed strategy and executing the crankcase gas heater activation strategy.

[0048] The initial rotational speed can be determined according to actual needs. For example, the initial rotational speed could be 4500±200 rpm. Fresh air enters the crankcase through the air filter and a one-way valve. Adjustment of the active oil-gas separator speed can be achieved through ECU control.

[0049] Furthermore, after executing the active oil-gas separator speed adjustment to the first speed strategy and the crankcase gas heater activation strategy, the process further includes: determining again whether the water vapor content is less than or equal to a preset water vapor content and the crankcase temperature is greater than a preset crankcase temperature. If not, the process returns to executing the active oil-gas separator speed adjustment to the first speed strategy and the crankcase gas heater activation strategy. If yes, the process executes the active oil-gas separator speed adjustment to the second speed strategy and the crankcase gas heater deactivation strategy.

[0050] The second speed can be determined according to actual needs; for example, the second speed can be 3000±200 rpm. The speed adjustment of the active oil-gas separator can be accomplished through ECU control.

[0051] Furthermore, after implementing the active oil-gas separator speed adjustment strategy to the second speed and the crankcase gas heater shutdown strategy, the following is also included:

[0052] Determine if the engine has stopped.

[0053] If the engine stops, control of the crankcase ventilation system is terminated.

[0054] If the engine is not stopped, return to the initial judgment step to determine whether the water vapor content is less than or equal to the preset water vapor content and the crankcase temperature is greater than the preset crankcase temperature.

[0055] This invention utilizes a closed-loop control system to operate the solenoid valve, crankcase gas heater, and active oil-gas separator. This allows for real-time monitoring of the water vapor content and temperature within the crankcase under different operating conditions, maintaining these levels within a reasonable range and reducing the risk of oil emulsification caused by water in hydrogen combustion products. This, in turn, prevents engine damage and extends engine life.

[0056] This invention also provides a crankcase capable of executing any of the above-described crankcase ventilation system control methods.

[0057] Since the crankcase in this embodiment of the invention can execute any of the above-mentioned crankcase ventilation system control methods, it has corresponding beneficial effects.

[0058] This invention also provides a vehicle including the aforementioned crankcase.

[0059] Since the vehicle in this embodiment of the invention includes the aforementioned crankcase, it has corresponding beneficial effects.

[0060] Note that the above description is merely a preferred embodiment of the present invention and the technical principles employed. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and various obvious changes, readjustments, combinations, and substitutions can be made without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in detail through the above embodiments, the present invention is not limited to the above embodiments, and may include many other equivalent embodiments without departing from the concept of the present invention, the scope of which is determined by the scope of the appended claims.

Claims

1. A control method for a crankcase ventilation system, characterized in that, include: Initially determine whether the conditions are met: water vapor content ≤ preset water vapor content, and crankcase temperature > preset crankcase temperature; If not, determine whether the intake manifold pressure is greater than the preset pressure value; If so, then execute the solenoid valve opening control strategy and the crankcase gas heater opening strategy. If not, then the active oil-gas separator speed is adjusted to the first speed strategy, and the crankcase gas heater is turned on strategy. The system then determines whether the conditions are met: water vapor content ≤ preset water vapor content, and crankcase temperature > preset crankcase temperature. If so, then execute the solenoid valve shutdown control strategy and the crankcase gas heater shutdown strategy; Determine if the engine has stopped; If the engine is not stopped, return to the initial determination of whether the water vapor content is less than or equal to the preset water vapor content and the crankcase temperature is greater than the preset crankcase temperature.

2. The crankcase ventilation system control method according to claim 1, characterized in that, After determining whether the engine has stopped, the method further includes: if the engine has stopped, then terminating the control of the crankcase ventilation system.

3. The crankcase ventilation system control method according to claim 1, characterized in that, After the initial determination of whether the water vapor content is less than or equal to the preset water vapor content and the crankcase temperature is greater than the preset crankcase temperature, the method further includes: if so, terminating the control of the crankcase ventilation system.

4. The crankcase ventilation system control method according to claim 1, characterized in that, After determining again whether the water vapor content is less than or equal to the preset water vapor content and the crankcase temperature is greater than the preset crankcase temperature, the method further includes: if not, returning to the step of executing the solenoid valve opening control strategy and executing the crankcase gas heater opening strategy.

5. The crankcase ventilation system control method according to claim 1, characterized in that, After executing the active oil-gas separator speed adjustment to the first speed strategy and the crankcase gas heater activation strategy, the method further includes: determining again whether the water vapor content is less than or equal to the preset water vapor content and the crankcase temperature is greater than the preset crankcase temperature; if not, then returning to the steps of executing the active oil-gas separator speed adjustment to the first speed strategy and the crankcase gas heater activation strategy.

6. The crankcase ventilation system control method according to claim 5, characterized in that, After determining again whether the water vapor content is less than or equal to the preset water vapor content and the crankcase temperature is greater than the preset crankcase temperature, the method further includes: if so, then the active oil-gas separator speed is adjusted to the second speed strategy, and the crankcase gas heater is turned off strategy.

7. The crankcase ventilation system control method according to claim 6, characterized in that, After implementing the strategy of adjusting the active oil-gas separator speed to the second speed and the strategy of shutting off the crankcase gas heater, the following steps are also included: Determine whether the engine has stopped; If the engine stops, control of the crankcase ventilation system is terminated; If the engine is not stopped, return to the initial determination of whether the water vapor content is less than or equal to the preset water vapor content and the crankcase temperature is greater than the preset crankcase temperature.

8. A crankcase, characterized in that, It is capable of performing the crankcase ventilation system control method according to any one of claims 1-7.

9. A vehicle, characterized in that, Includes the crankcase as described in claim 8.

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