Fault detection method for oil pump of hybrid power transmission

Abstract

The invention discloses a hybrid power transmission oil pump fault detection method, and belongs to the technical field of oil pump fault detection. A fault pre-processing module is designed in an automatic test tool to realize pre-judgment and processing of faults; therefore, the problem that subsequent tests are interfered due to the fact that faults are not cleared during repeated tests is solved. According to the method, the execution sequence of the test cases is ingeniously designed, all activation conditions and deactivation conditions can be tested through one test case, the tested signal is set as the variable signal a through modular thinking, all repeated actions are built into a basic action module, the reusability of the test module is improved, and the test efficiency is greatly improved. The problems that the workload is large and errors are prone to occurring when fault type signals are numerous and manual testing is conducted are solved.

Description

Technical Field

[0001] The invention belongs to the technical field of oil pump fault detection, and in particular to a hybrid transmission oil pump fault detection method. Background Art

[0002] The hybrid transmission controller changes the oil circuit pressure by controlling the oil pump, thereby causing the clutch to engage or disengage. In this process, the oil pump is an important actuator. When it fails, the hybrid transmission controller needs to identify and handle it in time. When performing hybrid transmission controller fault detection and processing function modules for the oil pump, two problems are often encountered. First, there are too many fault problems, which require repeated testing. However, after the previous test case is executed, when executing the next test case, the fault in the controller is not cleared in time, resulting in interference with subsequent tests. Second, there are many fault signals, and manual testing is labor-intensive and error-prone. Summary of the invention

[0003] The technical solution of the present invention is as follows: a hybrid transmission oil pump fault detection method comprises the following steps:

[0004] S1 test starts and the counter returns to the initial value;

[0005] S2 determines whether there is an oil pump failure. If the result is no, the result is output: the pre-processing test is passed; if the result is yes, step S3 is executed;

[0006] S3 clears the fault and waits for time T, the counter value +1.

[0007] S4 determines whether there is an oil pump failure. If the result is no, the result is output: the pre-processing test is passed; if the result is yes, the counter value is judged and S5 is executed.

[0008] S5: If the counter value in the previous step is ≤3, then execute from step S3 in sequence; if it is >3, then execute S6;

[0009] S6: Output result: The fault cannot be cleared and the preprocessing test fails.

[0010] Furthermore, step S2 is specifically as follows:

[0011] S201 Fault signal definition: define the oil pump fault signal as signal a;

[0012] S202 calls the fault preprocessing module to clear the previous fault;

[0013] S203 sets the IG OFF signal, creates a signal a fault and waits for T1 seconds;

[0014] S204 determines whether CCUA correctly outputs the fuel pump fault signal confirmed by diagnosis to indicate that there is a fault. If CCUA outputs the fuel pump fault signal confirmed by diagnosis to indicate that there is no fault, the test continues. If CCUA outputs the fuel pump fault signal confirmed by diagnosis to indicate that there is a fault, the test ends and the test fails.

[0015] S205 sets the IG ON signal and waits for T1 seconds;

[0016] S206 determines whether CCUA correctly outputs the fuel pump fault signal confirmed by diagnosis. If CCUA outputs the fuel pump fault signal confirmed by diagnosis, the test continues. If CCUA does not output the fuel pump fault signal confirmed by diagnosis, the test ends and the test fails.

[0017] S207 sets IG OFF and waits for T2 seconds.

[0018] S208 determines whether CCUA correctly outputs the fuel pump fault signal confirmed by diagnosis to indicate that there is a fault. If CCUA outputs the fuel pump fault signal confirmed by diagnosis to indicate that there is no fault, the test continues. If CCUA outputs the fuel pump fault signal confirmed by diagnosis to indicate that there is a fault, the test ends and the test fails.

[0019] S209 sets the IG ON signal and waits for T1 seconds, clears the signal a fault, and waits for T2 seconds;

[0020] S210 determines whether CCUA correctly outputs the fuel pump fault signal confirmed by diagnosis as faulty. If CCUA outputs the fuel pump fault signal confirmed by diagnosis as no fault, the test passes. If CCUA outputs the fuel pump fault signal confirmed by diagnosis as faulty, the test ends and the test fails.

[0021] Furthermore, oil pump failures include: oil pump low voltage fault signal, oil pump overvoltage fault signal, oil pump overtemperature fault signal, oil pump position sensor fault signal, oil pump internal fault signal, oil pump overcurrent fault signal, oil pump signal abnormal fault signal, oil pump stuck fault signal, oil pump system fault signal and oil pump derating fault signal.

[0022] The beneficial effects of the present invention are:

[0023] The present invention implements pre-judgment and processing of faults by designing a fault preprocessing module in the automated test tool, thereby solving the problem of interference with subsequent tests caused by failure to clear faults during repeated tests. The present invention cleverly designs the test case execution sequence to achieve the goal of testing all activation conditions and deactivation conditions through one test case, and through modular thinking, sets the measured signal as a variable signal a, and builds all repeated actions into basic action modules, thereby improving the reusability of the test module and greatly improving the test efficiency. It solves the problem of large workload and easy errors when manually testing a large number of fault-type signals. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 Schematic diagram of signal transmission relationship of the present invention.

[0025] Figure 2 This is a schematic diagram of fault preprocessing of the present invention.

[0026] Figure 3 This is a schematic diagram of the fault test of the present invention. DETAILED DESCRIPTION

[0027] It should be noted that in the description of the present invention, the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside", "clockwise", "counterclockwise", etc. indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction.

[0028] In the present invention, unless otherwise clearly specified and limited, the terms "set", "install", "connect", "connect" and the like should be understood in a broad sense. For example, "fixed" can be a fixed connection, a detachable connection, or an integral connection; the connection can be a mechanical connection or an electrical connection; the connection can be a direct connection or an indirect connection through an intermediate medium, and can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0029] After the oil pump controller (hereinafter referred to as PCBA) detects that the oil pump has a fault, it will transmit the oil pump fault signal to the hybrid transmission controller (hereinafter referred to as CCUA). CCUA will diagnose and process the signal sent by PCBA, and transmit the diagnosed confirmed oil pump fault signal to the vehicle controller (hereinafter referred to as VCU). There are ten types of faults sent by PCBA, namely: oil pump low voltage fault signal, oil pump overvoltage fault signal, oil pump overtemperature fault signal, oil pump position sensor fault signal, oil pump internal fault signal, oil pump overcurrent fault signal, oil pump signal abnormal fault signal, oil pump stuck fault signal, oil pump system fault signal, oil pump derating fault signal. The signal transmission relationship is as follows: Figure 1 shown.

[0030] The activation conditions for all the above faults are: the vehicle IG is ON, and the oil pump fault signal appears for a duration exceeding the detection time threshold T1. In particular, when the vehicle IG is OFF or the detection time threshold T1 is not reached, even if the fault is triggered, CCUA will output the oil pump fault signal confirmed by diagnosis as no fault.

[0031] The deactivation conditions for all the above faults are: under the condition that CCUA outputs the fuel pump fault signal confirmed by diagnosis, when the vehicle IG is OFF, or after the fault is cleared and the duration exceeds the detection time threshold T2, the fuel pump fault signal confirmed by diagnosis output by CCUA is no fault.

[0032] Fault preprocessing module process design Figure 2 The output of this module is: preprocessing passed, preprocessing failed.

[0033] S1: The test starts and the counter returns to the initial value 0.

[0034] S2: Determine whether there is an oil pump failure. If the result is no, output the result: pre-processing test passed; if the result is yes, execute step S3.

[0035] S3: Clear the fault and wait T3s, the counter value +1.

[0036] S4: Determine whether there is an oil pump failure. If the result is no, output the result: pre-processing test passed; if the result is yes, perform counter value judgment and execute S5.

[0037] S5: If the counter value in the previous step is less than or equal to 3, then execute from step S3 in sequence; if it is greater than 3, then execute S6.

[0038] S6: Output result: The fault cannot be cleared and the preprocessing test fails.

[0039] Oil pump fault diagnosis software function test flow chart design Figure 3 shown.

[0040] The overall idea is: fault preprocessing → test whether the fault can be reported when the fault exists but the power is not on → test whether the fault can be reported when the fault exists and the power is on → test whether the fault can be eliminated under the condition of power off after the fault information is output → test whether the fault can be eliminated under the condition of power off but clearing the fault signal after the oil pump fault signal is diagnosed and confirmed.

[0041] The specific test steps are as follows:

[0042] The first set of tests: Oil pump low voltage fault test

[0043] S1: Fault signal definition: The oil pump low voltage fault signal is defined as signal a.

[0044] S2: Call the fault preprocessing module to clear the previous fault.

[0045] S3: Set IG OFF signal, create signal a fault and wait T1s.

[0046] S4: Determine whether CCUA correctly outputs the fuel pump fault signal confirmed by diagnosis as having a fault. If CCUA outputs the fuel pump fault signal confirmed by diagnosis as having no fault, the test continues. If CCUA outputs the fuel pump fault signal confirmed by diagnosis as having a fault, the test ends and the test fails.

[0047] S5: Set the IG ON signal and wait for T1s.

[0048] S6: Determine whether CCUA correctly outputs the fuel pump fault signal confirmed by diagnosis. If CCUA outputs the fuel pump fault signal confirmed by diagnosis, the test continues. If CCUA does not output the fuel pump fault signal confirmed by diagnosis, the test ends and the test fails.

[0049] S7: Set IG OFF and wait for T2s.

[0050] S8: Determine whether CCUA correctly outputs the fuel pump fault signal confirmed by diagnosis as faulty. If CCUA outputs the fuel pump fault signal confirmed by diagnosis as no fault, the test continues. If CCUA outputs the fuel pump fault signal confirmed by diagnosis as faulty, the test ends and the test fails.

[0051] S9: Set the IG ON signal and wait for T1s, clear the signal a fault, and wait for T2s.

[0052] S10: Determine whether CCUA correctly outputs the fuel pump fault signal confirmed by diagnosis to indicate that there is a fault. If CCUA outputs the fuel pump fault signal confirmed by diagnosis to indicate that there is no fault, the test passes. If CCUA outputs the fuel pump fault signal confirmed by diagnosis to indicate that there is a fault, the test ends and the test fails.

[0053] After the above steps, all test conditions of the oil pump low voltage fault signal test can be completed. However, we will find that in addition to this signal, there are nine oil pump fault signals that need to be tested. If each signal is tested according to the above process, it will be too cumbersome. Therefore, this patent adopts a modular thinking, defines the signal to be tested as signal a, and encapsulates steps S2 to S10 in the above process into a basic test case module 01, then our subsequent test is simplified to:

[0054] The second test group: oil pump overvoltage fault test

[0055] S1: The oil pump overvoltage fault signal is defined as signal a.

[0056] S2: Call the basic test case module 01.

[0057] The third test group: oil pump overtemperature fault test

[0058] S1: The oil pump overvoltage fault signal is defined as signal a.

[0059] S2: Call basic test case module 01

[0060] In this way, all other fault types can be tested, achieving our goal of covering all oil pump fault software function tests.

[0061] 1. The difference between the oil pump xx fault signal and the oil pump fault signal confirmed by diagnosis. As the main body, the hybrid transmission controller (i.e., CCUA) described in this patent focuses on the difference. The oil pump xx fault signal is the input signal of CCUA. CCUA needs to judge and process this type of signal, while the oil pump fault signal confirmed by diagnosis means that CCUA has determined that the oil pump is in a faulty state and cannot work normally. It needs to transmit a signal to the vehicle controller (i.e., VCU). This signal is the oil pump fault signal confirmed by diagnosis.

[0062] 2. The fault clearing operation appears twice in this patent, namely in the fault preprocessing module S1 step and the oil pump fault diagnosis software functional test. In the fault preprocessing module S1 step, since it is a general fault judgment and processing, the fault clearing here means clearing all faults (a debugging port has been made in the model, and all faults can be cleared with one click). In the oil pump fault diagnosis software functional test, the faults injected in this step are cleared. For example, the oil pump low voltage fault is injected in the initial step, and only the oil pump low voltage fault is cleared in this step, which is used to determine the CCUA's processing of clearing the fault signal.

[0063] The above is only a specific implementation of the present invention, but the protection scope of the present invention is not limited thereto. Any modification, equivalent replacement and improvement made by any person skilled in the art within the technical scope disclosed by the present invention and within the spirit and principle of the present invention shall be covered within the protection scope of the present invention. At the same time, the contents not described in detail in this specification belong to the prior art known to those skilled in the art.

[0064] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

Claims

1. A hybrid transmission oil pump fault detection method, characterized in that: The following steps are involved: S1 test starts and the counter returns to the initial value; S2 determines whether there is an oil pump failure. If the result is no, it outputs the result: pre-processing test passed; If the result is yes, execute step S3; S3 clears the fault and waits for time T, the counter value +1. S4 determines whether there is an oil pump failure. If the result is no, the result is output: the pre-processing test is passed; If the answer is yes, the counter value is judged and S5 is executed. S5: If the counter value in the previous step is ≤3, then execute from step S3 in sequence; if it is >3, then execute S6; S6: Output result: The fault cannot be cleared and the preprocessing test fails.

2. A hybrid transmission oil pump fault detection method according to claim 1, characterized in that: Step S2 is specifically as follows: S201 fault signal definition: defining the oil pump fault signal as signal a; S202 calls the fault preprocessing module to clear the previous fault; S203 sets the IG OFF signal, creates a signal a fault and waits for T1 seconds; S204 determines whether CCUA correctly outputs the fuel pump fault signal confirmed by diagnosis to indicate that there is a fault. If CCUA outputs the fuel pump fault signal confirmed by diagnosis to indicate that there is no fault, the test continues. If CCUA outputs the fuel pump fault signal confirmed by diagnosis to indicate that there is a fault, the test ends and the test fails. S205 sets the IG ON signal and waits for T1 seconds; S206 determines whether CCUA correctly outputs the fuel pump fault signal confirmed by diagnosis. If CCUA outputs the fuel pump fault signal confirmed by diagnosis, the test continues. If CCUA does not output the fuel pump fault signal confirmed by diagnosis, the test ends and the test fails. S207 sets IG OFF and waits for T2 seconds. S208 determines whether CCUA correctly outputs the fuel pump fault signal confirmed by diagnosis to indicate that there is a fault. If CCUA outputs the fuel pump fault signal confirmed by diagnosis to indicate that there is no fault, the test continues. If CCUA outputs the fuel pump fault signal confirmed by diagnosis to indicate that there is a fault, the test ends and the test fails. S209 sets the IG ON signal and waits for T1 seconds, clears the signal a fault, and waits for T2 seconds; S210 determines whether CCUA correctly outputs the fuel pump fault signal confirmed by diagnosis as faulty. If CCUA outputs the fuel pump fault signal confirmed by diagnosis as no fault, the test passes. If CCUA outputs the fuel pump fault signal confirmed by diagnosis as faulty, the test ends and the test fails.

3. A hybrid transmission oil pump fault detection method according to claim 2, characterized in that: Oil pump failures include: oil pump low voltage fault signal, oil pump overvoltage fault signal, oil pump overtemperature fault signal, oil pump position sensor fault signal, oil pump internal fault signal, oil pump overcurrent fault signal, oil pump signal abnormal fault signal, oil pump stuck fault signal, oil pump system fault signal and oil pump derating fault signal.

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