Cavitation detection method and system for oil pump, medium and vehicle
By collecting operating parameters in the hybrid engine and performing integral comparison using a map operating condition table, the cavitation fault of the oil pump is diagnosed, solving the problem of oil pump body damage and achieving timely detection and life extension.
Patent Information
- Application Number
- CN202511238631.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-09-01
- Publication Date
- 2025-10-28
AI Technical Summary
Existing technology cannot detect cavitation in the oil pump of a hybrid engine in a timely manner, which can lead to damage to the oil pump body.
By collecting the actual operating parameters of the hybrid engine, integrating them using the map operating condition table, and comparing the actual integrated data with the cavitation integrated data, the cavitation fault of the oil pump can be diagnosed.
Timely detection of cavitation faults in the oil pump can prevent damage to the pump body and extend the life of the oil pump.
Smart Images
Figure CN120845152A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of cavitation detection technology, and in particular to a method, system, medium, and vehicle for detecting cavitation in an oil pump. Background Technology
[0002] In hybrid engines, a lubrication system equipped with a MAP oil pump is generally used to meet the minimum oil pressure requirements under different loads and speeds, thereby achieving the goal of energy saving and emission reduction.
[0003] The lubrication system equipped with a MAP oil pump mainly adjusts the oil pressure by regulating the solenoid valve of the oil pump. The greater the oil pump's pumping capacity, the higher the oil pressure.
[0004] In practical applications, if the lubrication system has internal leaks or certain oil-using components (such as the oil holes of the camshaft, bearings, etc.) experience abnormal wear leading to increased leakage, the usual approach is to adjust the oil pump solenoid valve to increase the oil pump's pumping volume to ensure the lubrication system's pressure requirements. However, this method is prone to cavitation. For example, when the engine is at extreme speeds of 4000 rpm and oil temperatures of 110°C, the oil pump's pumping volume will increase significantly, making cavitation highly likely and ultimately damaging the oil pump body.
[0005] Therefore, the problem with existing technology is: how to detect cavitation in a timely manner to avoid damage to the oil pump body. Summary of the Invention
[0006] To detect cavitation in a timely manner, this invention provides a method, system, medium, and vehicle for detecting cavitation in an oil pump. When the hybrid engine is running, the actual operating parameters of the hybrid engine are collected and integrated, and cavitation test operating parameters under the same operating conditions are also integrated. Based on the comparison between the actual integrated data and the cavitation integrated data, cavitation faults in the oil pump can be diagnosed in a timely manner, thereby avoiding damage to the oil pump body and extending the oil pump's lifespan.
[0007] To address the aforementioned technical problems, a first aspect of the present invention discloses a method for detecting cavitation in an oil pump, wherein the oil pump is installed in the lubrication system of a hybrid engine, the method comprising:
[0008] When the hybrid engine is running, the actual operating parameters of the hybrid engine are collected; wherein, the actual operating parameters include one or more of the following: the actual engine speed, the actual oil temperature corresponding to the oil pump, and the actual duty cycle of the oil pump solenoid valve.
[0009] Integrate the target parameter in the actual operating parameters to obtain actual integral data; wherein, the target parameter is one of the following: the actual engine speed, the actual duty cycle of the oil pump solenoid valve;
[0010] Using the associated parameters of the target parameters, cavitation test operating parameters under the same operating conditions are selected from the map operating condition table, and the cavitation test operating parameters are integrated to obtain cavitation integral data; wherein, the cavitation test operating parameters are one of the following: engine cavitation speed, oil pump solenoid valve cavitation duty cycle; the map operating condition table is an operating condition table drawn by the oil pump unit under critical cavitation phenomenon, with the cavitation test operating parameters as the observation object and the associated parameters corresponding to the cavitation test operating parameters being continuously adjusted.
[0011] Based on the comparison results between the actual integral data and the cavitation integral data, the cavitation fault of the oil pump is detected.
[0012] Optionally, if the target parameter is the actual engine speed, the associated parameters are: the actual duty cycle of the oil pump solenoid valve and the actual oil temperature;
[0013] The step of selecting cavitation test operating parameters under the same operating conditions from the map operating condition table using the correlation parameters of the target parameters, and integrating the cavitation test operating parameters to obtain cavitation integral data, specifically includes:
[0014] Based on the actual duty cycle of the oil pump solenoid valve and the actual oil temperature, the engine cavitation speed under the same operating conditions is found in the map operating condition table.
[0015] The cavitation speed of the engine under the same operating conditions is integrated to obtain the cavitation integral data.
[0016] Optionally, if the target parameter is the actual engine speed and the cavitation test operating parameter is the engine cavitation speed, the step of detecting the cavitation fault of the oil pump based on the comparison result of the actual integral data and the cavitation integral data specifically includes:
[0017] Compare the actual integral data corresponding to the actual engine speed and the cavitation integral data corresponding to the engine cavitation speed within a set monitoring time.
[0018] If the number of times the actual integral data corresponding to the actual engine speed is higher than the cavitation integral data corresponding to the engine cavitation speed reaches a first set threshold, it is determined that the oil pump has the cavitation fault.
[0019] Optionally, if the target parameter is the actual engine speed and the cavitation test operating parameter is the engine cavitation speed, the step of detecting the cavitation fault of the oil pump based on the comparison result of the actual integral data and the cavitation integral data specifically includes:
[0020] The speed integral over-limit ratio is determined within a set monitoring time; wherein, the speed integral over-limit ratio is the ratio of the integral difference between the actual integral data corresponding to the actual engine speed and the cavitation integral data corresponding to the engine cavitation speed to the cavitation integral data corresponding to the engine cavitation speed.
[0021] If the number of times the integral speed exceeds the first threshold reaches the first threshold, it is determined that the oil pump has the cavitation fault.
[0022] If the number of times the integral speed exceeds the second proportional threshold reaches the second number threshold, it is determined that the oil pump has the cavitation fault; wherein, the first proportional threshold is less than the second proportional threshold, and the first number threshold is greater than the second number threshold.
[0023] Optionally, if the target parameter is the actual duty cycle of the oil pump solenoid valve, the associated parameters are: the actual engine speed and the actual oil temperature;
[0024] The step of selecting cavitation test operating parameters under the same operating conditions from the map operating condition table using the correlation parameters of the target parameters, and integrating the cavitation test operating parameters to obtain cavitation integral data, specifically includes:
[0025] Based on the actual engine speed and the actual oil temperature, find the cavitation duty cycle of the oil pump solenoid valve under the same operating conditions in the map operating condition table.
[0026] The cavitation duty cycle of the oil pump solenoid valve under the same operating conditions is integrated to obtain the cavitation integral data.
[0027] Optionally, if the target parameter is the actual duty cycle of the oil pump solenoid valve, and the cavitation test operating parameter is the cavitation duty cycle of the oil pump solenoid valve, then detecting the cavitation fault of the oil pump based on the comparison result of the actual integral data and the cavitation integral data specifically includes:
[0028] Compare the actual integral data corresponding to the actual duty cycle of the oil pump solenoid valve and the cavitation integral data corresponding to the cavitation duty cycle of the oil pump solenoid valve within the set monitoring time.
[0029] If the number of times the actual integral data corresponding to the actual duty cycle of the oil pump solenoid valve is lower than the number of times the cavitation integral data corresponding to the cavitation duty cycle of the oil pump solenoid valve is lower than the second set threshold number, it is determined that the oil pump has the cavitation fault.
[0030] Optionally, if the target parameter is the actual duty cycle of the oil pump solenoid valve, and the cavitation test operating parameter is the cavitation duty cycle of the oil pump solenoid valve, then detecting the cavitation fault of the oil pump based on the comparison result of the actual integral data and the cavitation integral data specifically includes:
[0031] The duty cycle integral exceeding the limit ratio is determined within a set monitoring time; wherein, the duty cycle integral exceeding the limit ratio is the ratio of the integral difference between the actual integral data corresponding to the actual duty cycle of the oil pump solenoid valve and the integral data corresponding to the cavitation duty cycle of the oil pump solenoid valve to the integral data corresponding to the cavitation duty cycle of the oil pump solenoid valve.
[0032] If the number of times the duty cycle integral exceeds the limit by less than the third threshold reaches the third threshold, it is determined that the oil pump has the cavitation fault.
[0033] If the number of times the duty cycle integral exceeds the limit by less than the fourth proportional threshold reaches the fourth number threshold, it is determined that the oil pump has the cavitation fault; wherein, the third proportional threshold is less than the fourth proportional threshold, and the third number threshold is less than the fourth number threshold.
[0034] A second aspect of the present invention discloses a cavitation detection system for an oil pump, the oil pump being assembled in the lubrication system of a hybrid engine, the system comprising:
[0035] The data acquisition module is used to acquire the actual operating parameters of the hybrid engine when the hybrid engine is running; wherein the actual operating parameters include one or more of the following: actual engine speed, actual oil pressure corresponding to the oil pump, actual oil temperature corresponding to the oil pump, and actual duty cycle of the oil pump solenoid valve.
[0036] The first integration module is used to integrate the target parameter in the actual operating parameters to obtain actual integrated data; wherein, the target parameter is one of the following: the actual engine speed, the actual duty cycle of the oil pump solenoid valve;
[0037] The second integration module is used to select cavitation test operating parameters under the same operating conditions from the map operating condition table using the associated parameters of the target parameters, and to integrate the cavitation test operating parameters to obtain cavitation integral data; wherein, the cavitation test operating parameters are one of the following: engine cavitation speed, oil pump solenoid valve cavitation duty cycle; the map operating condition table is an operating condition table drawn by the oil pump unit under critical cavitation phenomenon, with the cavitation test operating parameters as the observation object and the associated parameters corresponding to the cavitation test operating parameters being continuously adjusted.
[0038] The detection module is used to detect cavitation faults in the oil pump based on the comparison results between the actual integral data and the cavitation integral data.
[0039] A third aspect of the present invention discloses a computer-readable storage medium having a computer program stored thereon that, when executed by a processor, implements the steps of the above-described method.
[0040] A fourth aspect of the present invention discloses a vehicle including a memory, a processor, and a computer program stored in the memory and executable on the vehicle processor, characterized in that the vehicle processor implements the steps of the above-described method when executing the program.
[0041] Through one or more technical solutions of the present invention, the present invention has the following beneficial effects or advantages:
[0042] This invention provides a method, system, medium, and vehicle for detecting cavitation in an oil pump. When the hybrid engine is running, the actual operating parameters of the hybrid engine are collected and integrated, and the cavitation test operating parameters under the same working conditions are also integrated. Based on the comparison results between the actual integrated data and the cavitation integrated data, the cavitation fault of the oil pump can be diagnosed in a timely manner, thereby avoiding damage to the oil pump body and extending the life of the oil pump.
[0043] The above description is merely an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention and to implement it in accordance with the contents of the specification, and in order to make the above and other objects, features and advantages of the present invention more apparent and understandable, specific embodiments of the present invention are described below. Attached Figure Description
[0044] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings:
[0045] Figure 1A flowchart of a method for detecting cavitation in an oil pump according to an embodiment of the present invention is shown;
[0046] Figures 2A-2B A schematic diagram of the cavitation speed of an oil pump according to an embodiment of the present invention is shown.
[0047] Figure 3 A schematic diagram of a cavitation detection system for an oil pump according to an embodiment of the present invention is shown. Detailed Implementation
[0048] Exemplary embodiments of the invention will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the invention are shown in the drawings, it should be understood that the invention may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this invention will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.
[0049] Exemplary embodiments of the invention will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the invention are shown in the drawings, it should be understood that the invention may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this invention will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.
[0050] First, as Figure 1 As shown, this embodiment of the invention provides a method for detecting cavitation in an oil pump. The oil pump is installed in the lubrication system of a hybrid engine and includes at least the following steps:
[0051] S101 collects the actual operating parameters of the hybrid engine while it is running.
[0052] The actual operating parameters include one or more of the following: actual engine speed, actual oil temperature corresponding to the oil pump, and actual duty cycle of the oil pump solenoid valve.
[0053] In the actual data collection process, once the target parameter in the actual operating parameters is determined, the corresponding associated parameters can be identified, allowing for targeted data collection. The target parameter is one of the following: actual engine speed, or actual duty cycle of the oil pump solenoid valve. If the target parameter is the actual engine speed, the corresponding associated parameters are: actual duty cycle of the oil pump solenoid valve, or actual oil temperature corresponding to the oil pump. If the target parameter is the actual duty cycle of the oil pump solenoid valve, the corresponding associated parameters are: actual engine speed, or actual oil temperature corresponding to the oil pump.
[0054] S102, Integrate the target parameter in the actual operating parameters to obtain the actual integral data.
[0055] If the target parameter is the actual engine speed, the specific operation for integrating the target parameter in the actual operating parameters is as follows: Integrate the actual engine speed over a set monitoring time period to obtain the actual integrated data corresponding to the actual engine speed. For example, integrate the actual engine speed over a set monitoring time t seconds. Among them, V m d represents the actual integral data corresponding to the actual engine speed V. t This represents the integral over a time variable t, where t is 3 seconds in an example, but this does not impose any restrictions.
[0056] If the target parameter is the actual duty cycle of the oil pump solenoid valve, the specific operation for integrating the target parameter in the actual operating parameters is as follows: Integrate the actual duty cycle of the oil pump solenoid valve within a set monitoring time to obtain the actual integrated data corresponding to the actual duty cycle of the oil pump solenoid valve. For example, integrate the actual duty cycle of the oil pump solenoid valve within a set monitoring time t seconds. Among them, C m This represents the actual integral data corresponding to the actual duty cycle C of the oil pump solenoid valve, d t This represents the integral over a time variable t, where t is 3 seconds in an example, but this does not impose any restrictions.
[0057] S103, using the associated parameters of the target parameters, select the cavitation test operating parameters under the same operating conditions from the map operating condition table, and integrate the cavitation test operating parameters to obtain cavitation integral data.
[0058] The operating parameters for the cavitation test are one of the following: engine cavitation speed, and oil pump solenoid valve cavitation duty cycle.
[0059] The map operating condition table is a table created by continuously adjusting the associated parameters corresponding to the cavitation test operating parameters of a single oil pump unit under critical cavitation conditions. Different operating condition tables will be obtained by observing different cavitation test operating parameters.
[0060] The following description is based on the conditions that the engine cavitation speed and the oil pump solenoid valve cavitation duty cycle are taken as the observation objects.
[0061] Engine cavitation speed V ′ When used as the object of observation, the corresponding related parameters are: oil pump solenoid valve duty cycle and oil temperature.
[0062] In individual oil pump tests, the cavitation speed of the engine under different oil displacements (i.e., different duty cycles) and oil temperatures is determined. Specifically, with the oil temperature and duty cycle fixed at their respective values, the relationship between oil pressure and engine speed is observed. When an inflection point appears in the engine speed, the speed corresponding to that inflection point is identified as the cavitation speed at a fixed temperature and a fixed duty cycle. For example... Figure 2A This is a schematic diagram showing the relationship between oil temperature and engine speed at a fixed oil temperature (e.g., 120℃) and a fixed duty cycle (e.g., X%). At this point, the engine speed inflection point of 4500 r / min is the cavitation speed, which corresponds to 120℃ and a fixed duty cycle of X%.
[0063] Once the cavitation speed is obtained for all oil temperatures and duty cycles, a cavitation speed map can be created. For example, with the oil temperature fixed at 120°C, a cavitation speed map can be created at 120°C, showing the correspondence between the oil pump solenoid valve duty cycle and the cavitation speed. See [link / reference] Figure 2B With the oil temperature fixed at 120℃, as the duty cycle of the oil pump solenoid valve gradually decreases, the cavitation speed also gradually decreases. Of course, a map-based operating condition table showing the correspondence between the oil pump solenoid valve duty cycle and the cavitation speed will also be drawn for other fixed oil temperatures. Alternatively, a map-based operating condition table showing the correspondence between oil temperature and cavitation speed can be drawn with the oil pump solenoid valve duty cycle fixed. This application does not impose any limitations on this.
[0064] If the target parameter is the actual engine speed, the associated parameters are: the actual duty cycle of the oil pump solenoid valve and the actual oil temperature. In the process of selecting cavitation test operating parameters under the same operating conditions from the map operating condition table using the associated parameters of the target parameter, and integrating the cavitation test operating parameters to obtain cavitation integral data, the engine cavitation speed under the same operating conditions is found in the map operating condition table based on the actual duty cycle of the oil pump solenoid valve and the actual oil temperature. The engine cavitation speed under the same operating conditions is then integrated to obtain cavitation integral data.
[0065] Specifically, since the operating conditions of a hybrid engine change in real time, after monitoring the actual oil pressure, the actual duty cycle of the oil pump solenoid valve, and the actual oil temperature, the engine cavitation speed V under the same operating conditions is first found in the map operating condition table based on the actual duty cycle C of the oil pump solenoid valve and the actual oil temperature T. ′ (C, T), the engine cavitation speed V is monitored within the set monitoring time. ′ Integrating (C, T), the integration operation is as follows: Among them, V i Indicates the engine cavitation speed V ′ (C, T) corresponding cavitation integral data, dt This represents the integral over a time variable t, where t is 3 seconds in an example, but this does not impose a constraint. If a leakage problem occurs inside the hybrid engine, for example, abnormal wear on a crankshaft bearing, resulting in a large oil leakage, in order to maintain the oil pressure required by the hybrid engine under the current operating conditions, such as ensuring that the target oil pressure is still maintained, it is necessary to reduce the actual duty cycle of the oil pump solenoid valve to increase the oil displacement. At this time, the actual oil temperature remains unchanged, and the engine cavitation speed will be found based on the reduced actual duty cycle of the oil pump solenoid valve.
[0066] The cavitation duty cycle C of the oil pump solenoid valve ′ When used as an observation object, the cavitation duty cycle C of the oil pump solenoid valve under different speeds and oil temperatures was determined in a single oil pump test. ′ And draw the map working condition table.
[0067] If the target parameter is the actual duty cycle of the oil pump solenoid valve, the associated parameters are: actual engine speed and actual oil temperature. When selecting cavitation test operating parameters under the same operating conditions from the map operating condition table using the associated parameters of the target parameter, and integrating the cavitation test operating parameters to obtain cavitation integral data, the cavitation duty cycle of the oil pump solenoid valve under the same operating conditions is found in the map operating condition table based on the actual engine speed and actual oil temperature. The cavitation duty cycle of the oil pump solenoid valve under the same operating conditions is then integrated to obtain cavitation integral data.
[0068] Specifically, based on the actual engine speed V and the actual oil temperature T, the cavitation duty cycle C of the oil pump solenoid valve under the same operating conditions is found in the map operating condition table. ′ (V, T), within the set monitoring time, the cavitation duty cycle C of the oil pump solenoid valve. ′ Integrating (V, T), the integration operation is as follows: Among them, C i Indicates the cavitation duty cycle C of the oil pump solenoid valve ′ The cavitation integral data corresponding to (V, T), d t This represents the integral over the time variable t, where t is 3 seconds in an example, but it does not impose any restrictions.
[0069] S104, based on the comparison results of actual integral data and cavitation integral data, detects cavitation faults in the oil pump.
[0070] During the comparison process, parameters such as the magnitude, ratio, and difference between the actual integral data and the cavitation integral data can be used to determine the cavitation fault of the oil pump.
[0071] In one optional implementation, if the target parameter is the actual engine speed and the cavitation test operating parameter is the engine cavitation speed, during the process of detecting cavitation faults in the oil pump based on the comparison results of the actual integral data and the cavitation integral data, the actual integral data corresponding to the actual engine speed and the cavitation integral data corresponding to the engine cavitation speed are compared within a set monitoring time. If the number of times the actual integral data corresponding to the actual engine speed is higher than the number of times the cavitation integral data corresponding to the engine cavitation speed is higher than the number of times reaches a first set threshold, it is determined that the oil pump has a cavitation fault.
[0072] For example, set the first set threshold number to 1. See Table 1 for the rotational speed comparison table.
[0073] Table 1
[0074] engine actual speed rpm Cavitation speed at 50% duty cycle (small to medium displacement) Cavitation speed at 20% duty cycle (large displacement) 3000 5000 2800 2900 5000 2800 3100 5000 2800
[0075] If the actual engine speed is 3000±100r / min, the oil temperature is 120℃, the oil pump duty cycle is 50% under normal conditions, and the oil pump is in a small to medium displacement state, then the oil pump cavitation speed is 5000r / min, which is greater than the current actual operating speed of 3000±100r / min, which is a safe state.
[0076] When an engine has internal leakage, such as abnormal wear on a crankshaft bearing, resulting in significant oil leakage, the oil pump solenoid valve is adjusted to 20% to maintain the required oil pressure under current operating conditions, increasing the displacement. At this point, the cavitation speed is 2800 rpm, which is less than the actual operating speed of 3000 ± 100 rpm, thus indicating a risk of cavitation. Therefore, this solution can promptly detect cavitation caused by excessive oil pump adjustment to a high displacement when internal leakage in the assembly worsens, thereby reducing the risk of pump damage.
[0077] If the number of times this risk occurs exceeds a first set threshold, such as once, then the oil pump is determined to have a cavitation fault.
[0078] In one optional implementation, if the target parameter is the actual engine speed and the cavitation test operating parameter is the engine cavitation speed, during the process of detecting cavitation faults in the oil pump based on the comparison results of the actual integral data and the cavitation integral data, the speed integral over-limit ratio is determined within a set monitoring time. The speed integral over-limit ratio is the ratio of the integral difference between the actual integral data corresponding to the actual engine speed and the cavitation integral data corresponding to the engine cavitation speed to the cavitation integral data corresponding to the engine cavitation speed, calculated as: T1 = (V m -V i ) / V i .
[0079] If the number of times the integral speed exceeding the limit ratio T1 exceeds the first proportional threshold reaches the first threshold, it is determined that the oil pump has a cavitation fault. For example, if the number of times the integral speed exceeding the limit ratio T1 exceeds 10% reaches 10 times, it is determined that the oil pump has a cavitation fault.
[0080] If the number of times the integral speed exceeding the limit ratio T1 exceeds the second proportional threshold reaches the second threshold, a cavitation fault is determined in the oil pump. Here, the first proportional threshold is less than the second proportional threshold, and the first threshold is greater than the second threshold. For example, if the integral speed exceeding the limit ratio T1 exceeds 50% twice, a cavitation fault is determined in the oil pump.
[0081] The reason for setting different percentage thresholds and different number of occurrence thresholds is that cavitation phenomena vary in severity. If the integral speed exceeding the limit ratio T1 is not high (e.g., above 10%), it indicates a mild cavitation phenomenon, so the number of occurrence thresholds are set higher, for example, cavitation faults are reported only after 10 occurrences. If the integral speed exceeding the limit ratio T1 is high (e.g., above 50%), it indicates a severe cavitation phenomenon, so the number of occurrence thresholds are set lower, for example, cavitation faults are reported only after 2 occurrences. By setting different detection strategies for different degrees of cavitation, no cavitation phenomenon in the oil pump will be missed, thus avoiding damage to the oil pump body and extending the life of the oil pump.
[0082] Furthermore, after confirming the cavitation fault of the oil pump, the engine malfunction indicator light is illuminated to indicate a lubrication system malfunction. The hybrid engine then shuts down for protection, prompting the user to bring the oil pump in for repair. This is to prevent prolonged damage to the oil pump body and extend the life of the oil pump.
[0083] In one optional implementation, if the target parameter is the actual duty cycle of the oil pump solenoid valve and the cavitation test operating parameter is the cavitation duty cycle of the oil pump solenoid valve, during the process of detecting cavitation faults in the oil pump based on the comparison results of the actual integral data and the cavitation integral data, the actual integral data corresponding to the actual duty cycle of the oil pump solenoid valve and the cavitation integral data corresponding to the cavitation duty cycle of the oil pump solenoid valve are compared within a set monitoring time. If the number of times the actual integral data corresponding to the actual duty cycle of the oil pump solenoid valve is lower than the number of times the cavitation integral data corresponding to the cavitation duty cycle of the oil pump solenoid valve reaches a second set threshold, it is determined that there is a cavitation fault in the oil pump.
[0084] In one optional implementation, if the target parameter is the actual duty cycle of the oil pump solenoid valve, and the cavitation test operating parameter is the cavitation duty cycle of the oil pump solenoid valve, during the process of detecting cavitation faults in the oil pump based on the comparison results of the actual integral data and the cavitation integral data, the duty cycle integral over-limit ratio is determined within a set monitoring time. The duty cycle integral over-limit ratio is the ratio of the integral difference between the actual integral data corresponding to the actual duty cycle of the oil pump solenoid valve and the cavitation integral data corresponding to the cavitation duty cycle of the oil pump solenoid valve, relative to the cavitation integral data corresponding to the cavitation duty cycle of the oil pump solenoid valve. The calculation method is: T2 = (C i -C m ) / C i If the number of times the duty cycle integral over-limit ratio T2 is lower than the third proportional threshold reaches the third number threshold, an oil pump cavitation fault is determined. If the number of times the duty cycle integral over-limit ratio T2 is lower than the fourth proportional threshold reaches the fourth number threshold, an oil pump cavitation fault is determined. The third proportional threshold is lower than the fourth proportional threshold, and the third number threshold is lower than the fourth number threshold. The reason for setting different proportional and number thresholds is that cavitation varies in severity. If the duty cycle integral over-limit ratio T2 is high (e.g., above 80%), it indicates a smaller displacement and milder cavitation; therefore, a higher number threshold is set, for example, 10 occurrences before an cavitation fault is reported. If the duty cycle integral over-limit ratio T2 is low (e.g., above 20%), it indicates a larger displacement and more severe cavitation; therefore, a lower number threshold is set, for example, 2 occurrences before an cavitation fault is reported. By setting different detection strategies for different degrees of cavitation, no oil pump cavitation will be missed, thus preventing pump body damage and extending oil pump life.
[0085] Furthermore, after confirming the cavitation fault of the oil pump, the engine malfunction indicator light is illuminated to indicate a lubrication system malfunction. The hybrid engine then shuts down for protection, prompting the user to bring the oil pump in for repair. This is to prevent prolonged damage to the oil pump body and extend the life of the oil pump.
[0086] It is worth noting that oil pump cavitation is a durability failure, and oil pump damage is also a durability process. Therefore, the integral time variable t and the set number threshold referenced in this application can be flexibly adjusted according to the actual degree of pump damage.
[0087] The technical solution provided by this invention collects and integrates the actual operating parameters of the hybrid engine during operation, and integrates the cavitation test operating parameters under the same working conditions. Based on the comparison results of the actual integrated data and the cavitation integrated data, the cavitation fault of the oil pump can be diagnosed in a timely manner, thereby avoiding damage to the oil pump body and extending the life of the oil pump.
[0088] Secondly, based on the same inventive concept as the oil pump cavitation detection method provided in the first aspect embodiment, this embodiment of the invention also provides an oil pump cavitation detection system, wherein the oil pump is installed in the lubrication system of a hybrid engine, see below. Figure 3 The system includes:
[0089] The acquisition module 301 is used to acquire the actual operating parameters of the hybrid engine when the hybrid engine is running; wherein the actual operating parameters include one or more of the following: actual engine speed, actual oil pressure corresponding to the oil pump, actual oil temperature corresponding to the oil pump, and actual duty cycle of the oil pump solenoid valve.
[0090] The first integration module 302 is used to integrate the target parameter in the actual operating parameters to obtain actual integrated data; wherein, the target parameter is one of the following: the actual engine speed, the actual duty cycle of the oil pump solenoid valve;
[0091] The second integration module 303 is used to select cavitation test operating parameters under the same operating conditions from the map operating condition table using the associated parameters of the target parameters, and to integrate the cavitation test operating parameters to obtain cavitation integral data; wherein, the cavitation test operating parameters are one of the following: engine cavitation speed, oil pump solenoid valve cavitation duty cycle; the map operating condition table is an operating condition table drawn by the oil pump unit under critical cavitation phenomenon, with the cavitation test operating parameters as the observation object and the associated parameters corresponding to the cavitation test operating parameters being continuously adjusted.
[0092] The detection module 304 is used to detect cavitation faults in the oil pump based on the comparison results between the actual integral data and the cavitation integral data.
[0093] It should be noted that the specific operation methods of each module in the oil pump cavitation detection system provided in the embodiments of the present invention have been described in detail in the method embodiments provided in the first aspect above. The specific implementation process can be referred to the method embodiments provided in the first aspect above, and will not be described in detail here.
[0094] Thirdly, based on the same inventive concept as the oil pump cavitation detection method provided in the first aspect embodiment, the present invention also discloses a computer-readable storage medium storing a computer program thereon, which, when executed by a processor, implements the steps of any of the methods described above.
[0095] Fourthly, based on the same inventive concept as the oil pump cavitation detection method provided in the first aspect embodiment, this embodiment of the invention also discloses a vehicle, including a memory, a processor, and a computer program stored in the memory and executable on the vehicle processor, wherein the vehicle processor executes the program to implement the steps of any of the methods described above.
[0096] Through one or more embodiments of the present invention, the present invention has the following beneficial effects or advantages:
[0097] This invention provides a method, system, medium, and vehicle for detecting cavitation in an oil pump. When the hybrid engine is running, the actual operating parameters of the hybrid engine are collected and integrated, and the cavitation test operating parameters under the same working conditions are also integrated. Based on the comparison results between the actual integrated data and the cavitation integrated data, the cavitation fault of the oil pump can be quickly diagnosed, thereby avoiding damage to the oil pump body and extending the life of the oil pump.
[0098] Although preferred embodiments of the invention have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including both the preferred embodiments and all changes and modifications falling within the scope of the invention.
[0099] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.
Claims
1. A method for detecting cavitation in an oil pump, wherein the oil pump is assembled in the lubrication system of a hybrid engine, characterized in that, The method includes: When the hybrid engine is running, the actual operating parameters of the hybrid engine are collected; wherein, the actual operating parameters include one or more of the following: the actual engine speed, the actual oil temperature corresponding to the oil pump, and the actual duty cycle of the oil pump solenoid valve. Integrate the target parameter in the actual operating parameters to obtain actual integral data; wherein, the target parameter is one of the following: the actual engine speed, the actual duty cycle of the oil pump solenoid valve; Using the associated parameters of the target parameters, cavitation test operating parameters under the same operating conditions are selected from the map operating condition table, and the cavitation test operating parameters are integrated to obtain cavitation integral data; wherein, the cavitation test operating parameters are one of the following: engine cavitation speed, oil pump solenoid valve cavitation duty cycle; the map operating condition table is an operating condition table drawn by the oil pump unit under critical cavitation phenomenon, with the cavitation test operating parameters as the observation object and the associated parameters corresponding to the cavitation test operating parameters being continuously adjusted. Based on the comparison results between the actual integral data and the cavitation integral data, the cavitation fault of the oil pump is detected.
2. The method as described in claim 1, characterized in that, If the target parameter is the actual engine speed, the associated parameters are: the actual duty cycle of the oil pump solenoid valve and the actual oil temperature; The step of selecting cavitation test operating parameters under the same operating conditions from the map operating condition table using the correlation parameters of the target parameters, and integrating the cavitation test operating parameters to obtain cavitation integral data, specifically includes: Based on the actual duty cycle of the oil pump solenoid valve and the actual oil temperature, the engine cavitation speed under the same operating conditions is found in the map operating condition table. The cavitation speed of the engine under the same operating conditions is integrated to obtain the cavitation integral data.
3. The method as described in claim 1 or 2, characterized in that, If the target parameter is the actual engine speed, and the cavitation test operating parameter is the engine cavitation speed, then detecting the cavitation fault of the oil pump based on the comparison result of the actual integral data and the cavitation integral data specifically includes: Compare the actual integral data corresponding to the actual engine speed and the cavitation integral data corresponding to the engine cavitation speed within a set monitoring time. If the number of times the actual integral data corresponding to the actual engine speed is higher than the cavitation integral data corresponding to the engine cavitation speed reaches a first set threshold, it is determined that the oil pump has the cavitation fault.
4. The method as described in claim 1 or 2, characterized in that, If the target parameter is the actual engine speed, and the cavitation test operating parameter is the engine cavitation speed, then detecting the cavitation fault of the oil pump based on the comparison result of the actual integral data and the cavitation integral data specifically includes: The speed integral over-limit ratio is determined within a set monitoring time; wherein, the speed integral over-limit ratio is the ratio of the integral difference between the actual integral data corresponding to the actual engine speed and the cavitation integral data corresponding to the engine cavitation speed to the cavitation integral data corresponding to the engine cavitation speed. If the number of times the integral speed exceeds the first threshold reaches the first threshold, it is determined that the oil pump has the cavitation fault. If the number of times the integral speed exceeds the second proportional threshold reaches the second number threshold, it is determined that the oil pump has the cavitation fault; wherein, the first proportional threshold is less than the second proportional threshold, and the first number threshold is greater than the second number threshold.
5. The method as described in claim 1, characterized in that, If the target parameter is the actual duty cycle of the oil pump solenoid valve, the associated parameters are: the actual engine speed and the actual oil temperature; The step of selecting cavitation test operating parameters under the same operating conditions from the map operating condition table using the correlation parameters of the target parameters, and integrating the cavitation test operating parameters to obtain cavitation integral data, specifically includes: Based on the actual engine speed and the actual oil temperature, find the cavitation duty cycle of the oil pump solenoid valve under the same operating conditions in the map operating condition table. The cavitation duty cycle of the oil pump solenoid valve under the same operating conditions is integrated to obtain the cavitation integral data.
6. The method as described in claim 1 or 5, characterized in that, If the target parameter is the actual duty cycle of the oil pump solenoid valve, and the cavitation test operating parameter is the cavitation duty cycle of the oil pump solenoid valve, then detecting the cavitation fault of the oil pump based on the comparison result of the actual integral data and the cavitation integral data specifically includes: Compare the actual integral data corresponding to the actual duty cycle of the oil pump solenoid valve and the cavitation integral data corresponding to the cavitation duty cycle of the oil pump solenoid valve within the set monitoring time. If the number of times the actual integral data corresponding to the actual duty cycle of the oil pump solenoid valve is lower than the number of times the cavitation integral data corresponding to the cavitation duty cycle of the oil pump solenoid valve is lower than the second set threshold number, it is determined that the oil pump has the cavitation fault.
7. The method as described in claim 1 or 2, characterized in that, If the target parameter is the actual duty cycle of the oil pump solenoid valve, and the cavitation test operating parameter is the cavitation duty cycle of the oil pump solenoid valve, then detecting the cavitation fault of the oil pump based on the comparison result of the actual integral data and the cavitation integral data specifically includes: The duty cycle integral exceeding the limit ratio is determined within a set monitoring time; wherein, the duty cycle integral exceeding the limit ratio is the ratio of the integral difference between the actual integral data corresponding to the actual duty cycle of the oil pump solenoid valve and the integral data corresponding to the cavitation duty cycle of the oil pump solenoid valve to the integral data corresponding to the cavitation duty cycle of the oil pump solenoid valve. If the number of times the duty cycle integral exceeds the limit by less than the third threshold reaches the third threshold, it is determined that the oil pump has the cavitation fault. If the number of times the duty cycle integral exceeds the limit by less than the fourth proportional threshold reaches the fourth number threshold, it is determined that the oil pump has the cavitation fault; wherein, the third proportional threshold is less than the fourth proportional threshold, and the third number threshold is less than the fourth number threshold.
8. A cavitation detection system for an oil pump, said oil pump being assembled in the lubrication system of a hybrid engine, characterized in that, The system includes: The data acquisition module is used to acquire the actual operating parameters of the hybrid engine when the hybrid engine is running; wherein the actual operating parameters include one or more of the following: actual engine speed, actual oil pressure corresponding to the oil pump, actual oil temperature corresponding to the oil pump, and actual duty cycle of the oil pump solenoid valve. The first integration module is used to integrate the target parameter in the actual operating parameters to obtain actual integrated data; wherein, the target parameter is one of the following: the actual engine speed, the actual duty cycle of the oil pump solenoid valve; The second integration module is used to select cavitation test operating parameters under the same operating conditions from the map operating condition table using the associated parameters of the target parameters, and to integrate the cavitation test operating parameters to obtain cavitation integral data; wherein, the cavitation test operating parameters are one of the following: engine cavitation speed, oil pump solenoid valve cavitation duty cycle; the map operating condition table is an operating condition table drawn by the oil pump unit under critical cavitation phenomenon, with the cavitation test operating parameters as the observation object and the associated parameters corresponding to the cavitation test operating parameters being continuously adjusted. The detection module is used to detect cavitation faults in the oil pump based on the comparison results between the actual integral data and the cavitation integral data.
9. A computer-readable storage medium having a computer program stored thereon, characterized in that, When executed by a processor, the program implements the steps of the method according to any one of claims 1-7.
10. A vehicle, comprising a memory, a processor, and a computer program stored in the memory and executable on an onboard processor, characterized in that, When the vehicle-mounted processor executes the program, it implements the steps of the method according to any one of claims 1-7.