JP6048728B2 - Fault diagnosis device for vehicle generator - Google Patents

Description

  The present invention relates to a vehicle generator failure diagnosis apparatus, and more particularly to a vehicle generator failure diagnosis apparatus capable of preventing erroneous diagnosis associated with a control state of a generator that generates electric power by power of an internal combustion engine.

In a vehicular generator that generates electric power by the power of an internal combustion engine mounted on a vehicle, a generator control device that controls a field current (excitation current) flowing in a coil constituting the generator and changes an output voltage is provided. Are known. Moreover, since the generator of a vehicle charges the battery which supplies electric power to an electric load, when a failure occurs, a malfunction occurs in using the vehicle. For this reason, the generator is provided with a failure diagnosis device that measures the output voltage output from the generator to the battery and determines whether it is normal.
However, the generator has a difference in the output voltage between when the temperature of the generator is low and when the temperature is high, even when the control device sets the field current and controls the same output voltage. Occur. For example, when the control device sends a signal to reduce the field current from 10 A to 7 A in order to reduce the charging voltage, the output voltage drops when the generator temperature is high and low. The width is different. Such a difference in output voltage causes a fault diagnosis device to generate a false diagnosis.
Therefore, in Patent Document 1 below, a warm-up state estimation unit for estimating the warm-up state of the generator is provided, and the control device determines the field according to the warm-up state of the generator estimated by the warm-up state estimation unit. The current is set and the output voltage is controlled to be the same. In this way, erroneous diagnosis of the failure diagnosis apparatus can be prevented.

JP 2007-306651 A

By the way, for the purpose of reducing fuel consumption and emission, the vehicle is stopped according to a predetermined condition such as when the vehicle is decelerating or stopped, and the stopped internal combustion engine is stopped for a predetermined operation such as an accelerator operation by a passenger. There is a vehicle equipped with a so-called idle stop control function that is restarted according to the above conditions.
In such a generator control device mounted on a vehicle, the power stored in the battery is reliably consumed by regenerative charging of the generator that is performed during deceleration. Therefore, as shown in FIG. A predetermined power generation delay period Ta is provided after t1, and during this power generation delay period Ta, control is performed so that the exciting current of the generator is stopped and power generation is delayed.
However, when such control is executed, there is a problem that the failure diagnosis device detects that the amount of power generation does not increase even though the generator is normal, and erroneously determines that the generator is faulty. In this case, the failure diagnosis device generates a power generation amount (output voltage) at a time t3 when a predetermined time Tb elapses from t2 when the rotation speed of the generator exceeds the failure diagnosis execution rotation speed after the restart t1 of the internal combustion engine. Since it increased and did not exceed the normal determination voltage, the generator was erroneously determined to be out of order even though it was within the power generation delay period Ta.
In short, conventionally, since the failure diagnosis of the failure diagnosis device is executed even during the delay of power generation (power generation delay period), there has been a problem of outputting an error (generator failure) as an insufficient amount of power generation.

  Therefore, the present invention has been made in view of the above problems, and provides a vehicle generator fault diagnosis apparatus that can accurately determine a fault even when control for delaying power generation is performed. The purpose is to provide.

  According to the present invention, an internal combustion engine applied to a vehicle, an engine stop control device that stops the internal combustion engine according to a predetermined condition, and restarts the internal combustion engine according to an operation of an occupant, and generates power using the power of the internal combustion engine. A generator, a power generation control unit that adjusts an excitation current to control the power generation amount of the generator, a failure diagnosis processing unit that diagnoses a failure of the generator, and at least the excitation from the restart of the internal combustion engine And a diagnosis invalidation processing unit for invalidating the diagnosis of the failure diagnosis processing unit for a predetermined period including a period until the current exceeds a set value.

  Since the diagnosis of the failure diagnosis processing unit is invalidated during the period from the start of restart of the internal combustion engine until the excitation current of the generator exceeds the set value, it is possible to prevent erroneous diagnosis accompanying the control state of the generator. The invalidation process may be a process for stopping the failure diagnosis performed by the failure diagnosis processing unit, or a process for rewriting the result of failure determination by the failure diagnosis processing unit to normal determination.

FIG. 1 is a block diagram of a failure diagnosis device for a vehicular generator. (Example) FIG. 2 is a flowchart of failure diagnosis execution determination processing of the failure diagnosis apparatus. (Example) FIG. 3 is a flowchart of the failure diagnosis process of the failure diagnosis apparatus. (Example) FIG. 4 is a flowchart of failure diagnosis invalidation processing of the failure diagnosis apparatus. (Example) FIG. 5 is a flowchart of the failure diagnosis invalid extension process of the failure diagnosis apparatus. (Example) FIG. 6 is a time chart of failure diagnosis processing of the failure diagnosis apparatus. (Example) FIG. 7 is a time chart of failure diagnosis processing of the failure diagnosis apparatus. (Conventional example)

  Embodiments of the present invention will be described below with reference to the drawings.

1 to 6 show an embodiment of the present invention. In FIG. 1, an internal combustion engine 1 applied to a vehicle includes a starter motor 2 for starting. The operation state of the internal combustion engine 1 is controlled by the internal combustion engine control device 3. The internal combustion engine control device 3 outputs a control signal to the internal combustion engine 1 based on the running state of the vehicle and the driving operation state of the occupant, and controls the operating state of the internal combustion engine 1.
The internal combustion engine control device 3 communicates information with the engine stop control device 4 through an in-vehicle communication network (LIN) 5, stops the internal combustion engine 1 according to a predetermined condition, and stops the stopped internal combustion engine 1. It restarts according to a predetermined condition.
The engine stop control device 4 is based on the accelerator pedal operation state detected by the accelerator position sensor 6, the brake pedal operation state detected by the brake position sensor 7, and the vehicle speed detected by the vehicle speed sensor (crank angle sensor) 8. Thus, a predetermined condition for stopping the internal combustion engine 1 and a predetermined condition for restarting the internal combustion engine 1 while it is stopped are determined.
The engine stop control device 4 outputs an engine stop signal to the internal combustion engine control device 3 in accordance with a predetermined condition such as when the vehicle is decelerated or stopped, and stops the internal combustion engine 1 (idle stop). Further, the engine stop control device 4 outputs an engine restart signal to the internal combustion engine control device 3 in accordance with a predetermined condition such as an accelerator depression operation by an occupant while the internal combustion engine 1 is stopped (idle stop). Is restarted.

The internal combustion engine 1 includes a vehicular generator (hereinafter referred to as a “generator”) 9 that generates electric power using the power of the internal combustion engine 1. The generator 9 includes a regulator 10 that adjusts an output voltage based on an adjustment voltage by an excitation current flowing through the rotor coil. The output voltage of the generator 9 adjusted by the regulator 10 is supplied to the first battery 11 and the second battery 12 for charging. The first battery 11 and the second battery 12 include the starter motor 2 and supply electric power to the electric load 13 of the vehicle.
The generator 9 includes a power generation state detection device 14 that detects a power generation state. The power generation state detection device 14 detects the excitation current flowing through the rotor coil and the output voltage supplied to the first battery 11 and the second battery 12, and sends information to the internal combustion engine control device 3 via the in-vehicle communication network (LIN) 5. Communicate.
The internal combustion engine control device 3 includes a power generation control unit 15. The power generation control unit 15 adjusts the excitation current to control the power generation amount of the generator 9 based on the excitation current and the output voltage detected by the power generation state detection device 14. The regulator 10 adjusts the output voltage with the exciting current, and supplies the first battery 11 and the second battery 12 for charging.
The internal combustion engine control device 3 includes a failure diagnosis processing unit 16 and a diagnosis invalidation processing unit 17. The failure diagnosis processing unit 16 diagnoses a failure of the generator 9. The diagnosis invalidation processing unit 17 performs a process of invalidating the diagnosis of the failure diagnosis processing unit 16 for a predetermined period including at least a period from the start of restart of the internal combustion engine 1 until the excitation current exceeds the set value.
In addition, the internal combustion engine control device 3 includes an invalid extension processing unit 18. The invalidation extension processing unit 18, after the elapse of a predetermined period by the diagnosis invalidation processing unit 17, until at least one of the excitation current and the adjustment voltage of the generator 9 exceeds the set value passes the set period. The invalidation process performed by the diagnosis invalidation processing unit 17 is extended.
The internal combustion engine 1, the internal combustion engine control device 3, the engine stop control device 4, a generator 9, a power generation state detection unit 14, a power generation control unit 15, a failure diagnosis processing unit 16, a diagnosis invalidation processing unit 17, and an invalid extension processing unit 18 Constitutes a fault diagnosis device 19 for the generator 9.
In the present embodiment, the in-vehicle communication network 5 has been described using LIN (Local Interconnect Network), but can be replaced with known communication means such as CAN (Controller Area Network), for example.

Next, the operation will be described.
In FIG. 2, the failure diagnosis device 19 of the generator 9 is a signal of an ignition switch (not shown) that is input to the internal combustion engine control device 3 when a failure diagnosis execution determination processing program is started by the failure diagnosis processing unit 16 (A01). Is OFF (A02). If this determination (A02) is YES, the process returns (A03). When this determination (A02) is NO, failure diagnosis processing (see FIG. 3) is performed (A04), and the process returns (A03).
As shown in FIG. 3, when the failure diagnosis processing program starts by the failure diagnosis processing unit 16 (B01), the failure diagnosis apparatus 19 determines whether the in-vehicle communication network (LIN) 5 is in communication abnormality (B02), It is determined whether the electrical abnormality failure diagnosis result of the generator 6 is abnormal (B03), it is determined whether the engine speed of the internal combustion engine 1 is equal to or higher than the failure diagnosis determination engine speed of the generator 9 (B04), It is determined whether the failure diagnosis invalid condition of the generator 9 (the internal combustion engine 1 is being started) is not established (B05), and a state in which all of the conditions based on these determinations (B02) to (B05) are established (YES) is a predetermined time. It is determined whether the process has been continued (B06).
If all of the determinations (B02) to (B06) are YES, it is determined that there is a failure (B07), and the process returns (B08). If any one of the determinations (B02) to (B06) is NO, the diagnosis is stopped (B09) and the process returns (B08).

As shown in FIG. 4, the failure diagnosis invalidation process based on the failure diagnosis invalid condition of the generator 9 starts the failure diagnosis invalidation processing program by the diagnosis invalidation processing unit 17 (C01). It is determined whether an engine stop signal is input to the control device 3 (C02). When there is an engine stop signal, the internal combustion engine 1 is stopped and the generator 9 is also stopped, so the failure diagnosis of the generator 9 is not performed.
Therefore, if the determination (C02) is YES, the failure diagnosis invalidation process is not necessary, so the failure diagnosis invalidation process is not executed and the process returns (C03). At this time, if the diagnosis invalidation processing unit 17 is executing the failure diagnosis invalidation process, the process is canceled.
If the determination (C02) is NO, an engine restart signal is input from the engine stop control device 4 to the internal combustion engine control device 3, and it is determined whether the internal combustion engine 1 is starting (C04). Whether the internal combustion engine 1 is being started is determined from the start of the internal combustion engine 1 by the starter motor 2 until the engine speed starts increasing until the engine speed exceeds the set speed. And judge.
If this determination (C04) is YES, it is determined that the failure diagnosis invalid condition is satisfied, the invalidation process is executed by the diagnosis invalidation processing unit 17 (C05), and the process returns (C03).
In the failure diagnosis disable process (C05), diagnosis and disabling processor 17, as shown in FIG. 6, until a predetermined period of time Tc including the time t5 at least the exciting current exceeds the set value from the restart start t1 of the internal combustion engine 1, a failure The process which invalidates the failure diagnosis which the diagnosis process part 16 performs is performed.
The failure diagnosis invalidation processing may stop the execution of the failure diagnosis of the failure diagnosis processing unit 16, and the determination result is determined to be normal regardless of the result of the failure diagnosis performed by the failure diagnosis processing unit 16. It may be rewritten.
If the diagnosis (C04) is NO, failure diagnosis invalid extension processing is executed (C06), and the process returns (C03).

In the failure diagnosis invalid extension process (C06) of the generator 9, as shown in FIG. 5, when the failure diagnosis invalid extension process program is started by the invalid extension processing unit 18 (D01), the timer of the internal combustion engine control device 3 is started. 20 starts counting the set period (D02), determines whether the adjustment voltage of the regulator 10 has exceeded the set value for the invalid extension process (D03), and has the excitation current of the regulator 10 exceeded the set value for the invalid extend process? (D04) and whether the count of the timer 20 has passed the set period is determined (D05).
If all of the determinations (D03) to (D05) are YES, the timer 20 is reset and the invalidation process is canceled (D06), and the process returns to the failure diagnosis invalidation extension process (C06) in FIG. 4 (D07). When any one of the determinations (D03) to (D05) is NO, the timer 20 continues counting and the invalidation process is continued (D08), and the process returns to the failure diagnosis invalidation extension process (C06) of FIG. D07).
Disable extension processing unit 18, as shown in FIG. 6, after the spent through the Tokoro periodically between Tc, either one of the excitation current or adjust voltage of at least the generator 9, setting the state exceeding the set value The invalidation process performed by the diagnosis invalidation processing unit 17 is extended until time t6 when the period Td elapses.

Thus, the failure diagnosis device 19 for the generator 9 invalidates the failure diagnosis for a predetermined period Tc from the start of restart of the internal combustion engine 1 until the excitation current of the generator 9 exceeds the set value. It is possible to prevent erroneous diagnosis associated with the control state. The invalidation process may be a process of stopping the failure diagnosis performed by the failure diagnosis processing unit 16 or a process of rewriting the result of the failure determination by the failure diagnosis processing unit 16 to a normal determination.
Further, the failure diagnosis device 19 of the generator 6 determines that the state in which the excitation current or the adjustment voltage of the generator 9 exceeds the set value after the predetermined period Tc of the invalidation process by the diagnosis invalidation processing unit 17 has passed the set period Td. Since the invalidation process is extended until the time elapses, it is possible to prevent the invalidation process from being canceled when the power generation amount of the generator 9 temporarily increases due to, for example, rapid acceleration. That is, when the power generation amount decreases after the temporary increase in the power generation amount, the failure diagnosis device 19 can be prevented from erroneously diagnosing the generator 9 as a failure.
The failure diagnosis device 19 reflects the result of the accurate failure determination in the lighting control of the charging warning light that is turned on when the generator 9 fails, so that the charging warning light is erroneously turned on due to a wrong diagnosis of the generator 9. Can be prevented.

  The present invention can accurately determine a failure even when control for delaying power generation is performed. If the vehicle includes a generator that generates power by an internal combustion engine, the present invention is applied to a four-wheeled vehicle. Not limited to two-wheeled vehicles.

DESCRIPTION OF SYMBOLS 1 Internal combustion engine 2 Starter motor 3 Internal combustion engine control apparatus 4 Engine stop control apparatus 5 In-vehicle communication network (LIN)
6 Accelerator position sensor 7 Brake position sensor 8 Vehicle speed sensor (crank angle sensor)
DESCRIPTION OF SYMBOLS 9 Generator 10 Regulator 11 1st battery 12 2nd battery 13 Electric load 14 Electric power generation state detection apparatus 15 Electric power generation control part 16 Failure diagnosis process part 17 Diagnosis invalid process part 18 Invalid extension process part 19 Failure diagnosis apparatus 20 Timer

Claims (2)

  An internal combustion engine applied to a vehicle, an engine stop control device that stops the internal combustion engine according to a predetermined condition, and restarts the internal combustion engine according to an operation of an occupant, a generator that generates electric power using the power of the internal combustion engine, A power generation control unit for adjusting an excitation current to control the power generation amount of the generator; a failure diagnosis processing unit for diagnosing a failure of the generator; and at least the excitation current from a restart start of the internal combustion engine A failure diagnosis apparatus for a vehicle generator, comprising: a diagnosis invalidation processing unit that performs a process of invalidating the diagnosis of the failure diagnosis processing unit for a predetermined period including a period of time exceeding   The failure diagnosis apparatus performs invalidation performed by the diagnosis invalidation processing unit until at least one of the excitation current and the adjustment voltage of the generator exceeds a set value after the set period elapses after the predetermined period has elapsed. The fault diagnosis device for a vehicular generator according to claim 1, further comprising an invalid extension processing unit that extends the processing.

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