JP2008260339A - Vehicle control device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a vehicle control device capable of preventing erroneous detection of failure and attaining detection of failure such as disconnection even at the occurrence of an event that ground potential is varied. <P>SOLUTION: The vehicle control device controls the vehicle by adjusting an opening of a proportional solenoid valve 27 according to a detection value of various kinds of sensors 32 attached to the vehicle, and is provided with a ground potential presumption means 113 for presuming the ground potential of the vehicle control device based on amplitude of a dither current superposed on a current value of the proportional solenoid valve 27; a sensor valve correction means 115 for correcting the detection value of the various kinds of sensors 32 from the ground potential presumed by the ground potential presumption means 113; a control means 120 for adjusting the opening of the proportional solenoid valve 27 based on the detection value of the various kinds of sensors 32 after corrected by the sensor value correction means 115; and a failure detection means 117 for performing abnormality detection of the various kinds of sensors 32 based on the detection value of the various kinds of sensors 32 after corrected by the sensor value correction means 115. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a vehicle control device that controls a vehicle by adjusting an opening degree of a proportional solenoid valve in accordance with detection values of various sensors mounted on the vehicle.

  In the conventional vehicle control device, when a sensor or the like mounted on the vehicle breaks down, the failure detection of those sensors or the like is performed in order to notify the driver or the like of the failure. The failure detection includes, for example, a method in which an analog voltage value output as a detection value by a sensor is measured and performed according to the analog voltage value.

  As an example of the failure detection method, when the output voltage value is abnormal, the counter is counted up, and when the output voltage is normal, the counter is counted down or cleared, and this counter value exceeds a predetermined value. It is conceivable that a failure is determined.

  The grounds of the vehicle control device and the on-vehicle device that consumes a large current (for example, the anti-lock brake control device) are grounded at the same location, and the ground of the sensor to be diagnosed is grounded separately from the vehicle control device. In the case where the vehicle mounted device consumes a large current, the ground potential of the vehicle control device becomes high.

  As the ground potential of the vehicle control device increases, the sensor value of the failure detection target apparently decreases from the original voltage value. As a result, there is a problem that an erroneous diagnosis is made as a failure even though the sensor to be diagnosed is not abnormal because the sensor value is apparently lowered.

  To deal with this problem, know in advance events that increase the ground potential of the vehicle control device by consuming a large current (for example, events such as the operation of an antilock brake system or the operation of a shift motor). If this occurs, it is determined that the ground potential of the vehicle control device is high, and there is a conventional technique that prevents erroneous detection by stopping the failure diagnosis of the sensor (for example, patent document) 1).

JP 2001-289066 A

However, the prior art has the following problems.
In Patent Document 1, while an event grasped in advance is operating, in order to prevent a fault from being erroneously detected due to a high ground potential, fault detection during that period is stopped. It was. However, even if the sensor value becomes abnormal due to the disconnection of the sensor in the state where the event grasped in advance is operating, the failure detection is stopped, so the disconnection of the sensor cannot be detected. There is a problem that the driver cannot be notified of the occurrence of the failure.

  Furthermore, in the control of the vehicle body using the value of the throttle position sensor, the vehicle is controlled using the sensor value that is abnormal because the ground potential becomes high while the anti-lock brake system is operating. Therefore, there is a problem that the vehicle is in a state not intended by the driver.

  Furthermore, if the ground potential becomes high due to a cause other than the event that has been grasped in advance, the fault is detected erroneously even though the sensor subject to fault diagnosis is not abnormal, and the driver It is necessary to deal with Further, in this case, there is a problem that the sensor is replaced by mistakenly diagnosing that the sensor is faulty, and unnecessary labor and cost are generated.

  The present invention has been made to solve the above-described problems, and even when an event such as a rise in ground potential occurs, it is possible to prevent erroneous detection of failure and to detect failure such as disconnection. An object of the present invention is to obtain a vehicle control device that performs the above-described operation.

  A vehicle control device according to the present invention superimposes on a current value of a proportional solenoid valve in a vehicle control device that controls the vehicle by adjusting the opening of the proportional solenoid valve according to detection values of various sensors mounted on the vehicle. A ground potential estimating means for estimating the ground potential of the vehicle control device based on the amplitude of the dither current, a sensor value correcting means for correcting detection values of various sensors from the ground potential estimated by the ground potential estimating means, and a sensor Based on the detection values of the various sensors after being corrected by the value correction means, based on the detection values of the various sensors after being corrected by the control means for adjusting the opening of the proportional solenoid valve, and the sensor value correction means, And a failure detection means for detecting abnormality of various sensors.

  According to the present invention, the ground potential after displacement is estimated based on the amplitude of the dither current superimposed on the current value of the proportional solenoid valve, and the detection values by various sensors are corrected based on the estimated ground potential. By using the detected value later to control the opening of the proportional solenoid valve and the abnormality detection process of various sensors, it is possible to prevent erroneous detection of a fault even when an event that causes an increase in ground potential occurs. Thus, it is possible to obtain a vehicle control device that enables failure detection such as disconnection.

  Hereinafter, preferred embodiments of a vehicle control device of the present invention will be described with reference to the drawings. In the following embodiments, a case where the vehicle control device is used for controlling a four-wheel drive vehicle will be described as an example.

Embodiment 1 FIG.
FIG. 1 is a diagram schematically illustrating a four-wheel drive vehicle that is a control target of the vehicle control device according to Embodiment 1 of the present invention. In FIG. 1, the four-wheel drive vehicle to be controlled by the vehicle control device 10 includes an engine 31, a throttle position sensor 32, a transmission 41, a center differential 42, a front differential 43, a rear differential 44, a clutch 45, a front left wheel 46, a front A right wheel 47, a rear left wheel 48, and a rear right wheel 49 are included.

  Torque generated by the engine 31 is transmitted to the transmission 41 and is decelerated or increased by the transmission 41. The output of the transmission 41 is transmitted to the center differential 42, and the center differential 42 transmits driving force to the front differential 43 and the rear differential 44.

  In a vehicle, a difference occurs in the rotational speed of the four wheels due to the difference in turning radius of the four wheels during cornering. Due to the difference in the rotational speed of the wheels, a so-called tight corner brake phenomenon occurs in which a force that hinders turning acts and the turning ability decreases.

  In order to absorb the difference in wheel speed and eliminate such a tight corner braking phenomenon, the vehicle is equipped with a differential gear. That is, a front differential 43 is attached to absorb the speed difference between the left and right front wheels, and a rear differential 44 is installed to absorb the speed difference between the left and right rear wheels. Further, in the four-wheel drive vehicle, a center differential 42 is provided to absorb the wheel speed difference between the front and rear wheels.

  In the front differential 43 that is one of the differential gears used to absorb the wheel speed difference, the rotation distributed from the center differential 42 is transmitted to the front left wheel 46 and the front right wheel 47. When the vehicle is traveling straight, the load applied to the front left wheel 46 and the front right wheel 47 is the same, so the front differential 43 evenly distributes the rotation transmitted from the center differential 42 to the front left wheel 46 and the front right wheel 47.

  On the other hand, for example, when the vehicle is turning left, the turning radius of the front left wheel 46 is smaller than the turning radius of the front right wheel 47, so the load applied to the front left wheel 46 is greater than the load applied to the front right wheel 47. Also grows. In this case, the front differential 43 transmits the rotation transmitted from the center differential 42 to the front right wheel 47 more than the front left wheel 46.

  The rear differential 44 also functions in the same manner as the front differential 43 with respect to the rear left wheel 48 and the rear right wheel 49. As described above, the differential gear has a property of distributing a large amount of rotation to a side with a small load.

  When the four-wheel drive vehicle accelerates rapidly, the vehicle body load is increased on the rear wheel side, and the load on the rear wheel increases. The center differential 42 transmits a large amount of rotation from the transmission 41 to the front wheels due to the property of transmitting the rotation to a direction with less load. As a result, the front wheels are easy to idle. Furthermore, when the front wheels are idle, the driving force is not easily transmitted to the rear wheels.

  In addition, the acceleration performance of the vehicle is improved by allocating a large amount of driving force to the tire with the greater load. Therefore, when a four-wheel drive vehicle accelerates suddenly, theoretically, the acceleration performance of the vehicle is improved by allocating more driving force to the rear wheels. However, the provision of the center differential 42 deteriorates its performance.

  Therefore, in order to prevent deterioration in acceleration performance due to the provision of the center differential 42, a device for limiting the differential of the center differential 42 is provided. In the first embodiment, a clutch 45 is provided as a differential limiting device.

  By controlling the restraining force of the clutch 45, the two output shafts of the center differential 42 can be controlled from a differential-free state to a state close to direct coupling, and the differential of the center differential 42 can be limited. Therefore, in the first embodiment, in order to improve the acceleration performance of the vehicle, the binding force of the clutch 45 is increased during acceleration and the differential of the center differential 42 is limited.

  The vehicle accelerates when an accelerator pedal is depressed and a throttle valve that sucks air into the engine is opened. Therefore, in the first embodiment, the vehicle control apparatus 10 measures the output of the throttle position sensor 32 that detects the opening of the throttle valve, calculates the clutch restraining force from the relationship between the value and the vehicle body speed, and determines the hydraulic pressure. Instruct the system 20 of the clutch restraining force.

  The hydraulic system 20 controls the hydraulic pressure applied to the clutch and controls the binding force of the clutch 45 in order to realize the binding force instructed by the vehicle control device 10.

  FIG. 2 is a diagram schematically showing the relationship between the hydraulic system 20 of the four-wheel drive vehicle and the vehicle control device 10 according to Embodiment 1 of the present invention. In FIG. 2, the hydraulic system 20 includes a pump 21, a motor 22, a check valve 23, a tank 24, an accumulator 25, a pressure sensor 26, a proportional electromagnetic valve 27, and a relief valve 28.

  The vehicle control device 10 outputs an operation instruction to the motor 22 from the vehicle control device 10 when it is desired to operate the pump 21. The motor 22 that has received the operation instruction is immediately activated, so that the pump 21 connected by the shaft is activated.

  When the pump 21 is operated, the hydraulic oil in the tank 24 is sent to the accumulator 25 through the check valve 23 provided to prevent the hydraulic oil from flowing back.

  The vehicle control device 10 processes the signal of the pressure sensor 26 and calculates the pump pressure. Then, the vehicle control device 10 operates to issue a stop instruction for the motor 22 when the pump pressure becomes larger than the pump stop pressure set value.

  On the other hand, the vehicle control device 10 operates to issue an operation instruction for the motor 22 when the pressure becomes smaller than the pressure setting value for pump operation. Further, the vehicle control device 10 determines the target opening degree of the proportional solenoid valve 27 and causes a current corresponding to the target opening degree to flow to the proportional solenoid valve 27.

  The proportional solenoid valve 27 supplies pressure to the clutch 45 by changing the opening according to the current flowing through the internal solenoid. When the current flowing through the proportional solenoid valve 27 is large, the opening degree of the proportional solenoid valve 27 is large and the binding force of the clutch 45 is large. On the other hand, when the current flowing through the proportional solenoid valve 27 is small, the opening degree of the proportional solenoid valve 27 is small, and the binding force of the clutch 45 is small.

  FIG. 3 is a detailed configuration diagram of the vehicle control device 10 according to the first embodiment of the present invention. The vehicle control device 10 of FIG. 3 includes a CPU 11, a drive circuit 12, current detection means 13, and an EEPROM 14.

  Further, the CPU 11 includes a dither amplitude measuring unit 111, an amplitude difference calculating unit 112, a ground potential estimating unit 113, a sensor value measuring unit 114, a sensor value correcting unit 115, a target current value determining unit 116, a failure detecting unit 117, and a failure notifying unit. 118, a dither correction unit 119, and a control unit 120.

  The internal circuit of the vehicle control device 10 having such a configuration is based on the ground G2. As an external circuit, a proportional solenoid valve 27 having one end connected to the ground G1 is connected to the current detection means 13 via the terminal 1, and the throttle position sensor 32 having the ground G1 as a reference is connected to the terminal 2 via the terminal 2. The sensor value measuring means 114 is connected.

  The CPU 11 in the vehicle control device 10 determines the PWM duty according to the value of the throttle position sensor 32. The drive circuit 12 turns on and off the transistor TR1 in accordance with the PWM duty determined by the CPU 11.

  The current detection means 13 measures the current flowing through the proportional solenoid valve 27 using the shunt resistor R1. The proportional solenoid valve 27 is composed of a solenoid, and the opening degree of the proportional solenoid valve 27 changes according to the value of the current flowing through the solenoid. The proportional solenoid valve 27 smoothes the spool operation by slightly vibrating the current flowing through the solenoid of the proportional solenoid valve 27 and reducing the friction coefficient in order to improve the hysteresis characteristics and responsiveness of the valve. Dither control is performed by the CPU 11.

  The EEPROM 14 stores the relationship between the reference amplitude and the amplitude difference and the ground potential in advance, and is used when the CPU 11 determines the PWM duty.

Next, the operation of the CPU 11 will be described in detail.
The dither amplitude measuring unit 111 inside the CPU 11 measures the dither amplitude from the measured current value detected by the current detecting unit 13. The amplitude difference calculation unit 112 calculates an amplitude difference between the reference amplitude value stored in the EEPROM 14 and the dither amplitude measured by the dither amplitude measurement unit 111. The ground potential estimation unit 113 estimates the potential of the ground G2 from the amplitude difference calculated by the amplitude difference calculation unit 112.

  On the other hand, the sensor value measuring means 114 measures the output voltage of the throttle position sensor 32. The sensor value correcting unit 115 corrects the sensor value measured by the sensor value measuring unit 114 in accordance with the potential of the ground G2 estimated by the ground potential estimating unit 113. Further, the target current value determining means 116 determines the target current value based on the corrected sensor value.

  The failure detection unit 117 performs failure detection using the sensor value corrected by the sensor value correction unit 115. When a failure occurs, the failure detection unit 117 notifies the driver of the failure that has occurred via the failure notification unit 118.

  The dither correction unit 119 performs dither correction on the target current value determined by the target current value determination unit 116. The control unit 120 performs the PI control so that the measured current value detected by the current detection unit 13 follows the target current value after the dither correction.

  Based on the PWM duty determined as a result of the PI control by the control means 120, the drive circuit 12 turns on and off the transistor TR1 and causes a current to flow through the proportional solenoid valve 27. A diode D1 is connected to absorb a surge generated when the transistor TR1 is off.

  FIG. 4 is a diagram showing a correspondence relationship between the target current value after dither correction in the steady state and the current of the proportional solenoid valve 27 in Embodiment 1 of the present invention. The dither correction unit 119 forms the target current value 53 after dither correction by adding and subtracting the dither correction amount 52 to the target current value 51 every predetermined time (for example, several msec).

  The control means 120 performs PI control in order to make the measured current measured by the current detection means 13 follow the target current value 53 after dither correction. By performing the PI control by the control means 120, the current flowing through the proportional solenoid valve 27 in a steady state becomes a proportional solenoid valve current 54 as shown in FIG. Further, by performing the PI control by the control unit 120, the average current value 55 follows the target current value 51 and becomes substantially equal.

  In the first embodiment, when the potential of the ground G2 becomes higher than the potential of the ground G1 due to the operation of the anti-lock brake system or the like, the diode D1, the shunt from the ground G2 regardless of whether the transistor TR1 is on or off. A current flows through the proportional solenoid valve 27 through the resistor R1. That is, the current detected by the shunt resistor R1 and the current detection means 13 is always offset by a current flowing from the ground G2 into the proportional solenoid valve 27.

  Thus, even when the measured current value detected by the current detection means 13 is offset, the PI control by the control means 120 is performed on the target current value 51, and therefore the average current value 55 is The target current value 51 is followed.

  On the other hand, the current value that actually flows from the battery (+ B) through the transistor TR1 and the shunt resistor R1 to the proportional solenoid valve 27 is obtained by subtracting the offset amount from the target current value 51, and the dither amplitude 56 is the current after the subtraction. The value corresponds to the value. As a result, the dither amplitude 56 becomes smaller than when the measured current value detected by the current detection means 13 is not offset.

  FIG. 5 is a diagram showing the relationship of the amplitude difference between the dither amplitude 56 and the reference amplitude with respect to the potential of the ground G2 in the first embodiment of the present invention. As shown in FIG. 5, since there is a linear function relationship between the ground potential G <b> 2 and the dither amplitude difference, the ground potential estimation means 113 in the CPU 11 calculates from the amplitude difference based on the measurement result of the dither amplitude 56. It is possible to estimate the potential of the ground G2.

  The potential of the ground G2 is estimated from the amplitude difference between the reference amplitude and the current dither amplitude 56 measured by the dither amplitude measuring means 111, with the dither amplitude 56 when the potential of the ground G2 is 0V as a reference amplitude. be able to.

  Therefore, in order to measure the potential of the ground G2, the dither amplitude when the potential of the ground G2 is 0 V is required as the reference amplitude. However, individual differences occur in this value due to variations in the resistance values of the transistor TR1, the shunt resistor R1, the proportional solenoid valve 27, and the like.

  Therefore, in order to eliminate such individual differences, in the first embodiment, the ground G1 and the ground G2 are grounded in common before the vehicle control apparatus 10 is actually used, that is, before shipment from the factory. The dither amplitude 56 is measured in a state where the potential difference of the ground G2 is 0 V, and the measurement result is stored in the EEPROM 14 as a reference amplitude. When the vehicle control device 10 is actually used, the value stored in the EEPROM 14 is used as the reference amplitude, and the potential of the ground G2 is estimated.

  Such measurement of the reference amplitude is performed by a shipping inspection apparatus before shipment from the factory.

  Furthermore, the following measures can be considered in order to suppress the variation of parts. Prior to factory shipment, a power source is connected between the ground G1 and the ground G2 with the ground G1 as a reference, and the dither amplitude 56 is measured when the voltage of the connected power source is increased. Then, an amplitude difference is obtained from the measured dither amplitude 56 and the reference amplitude, and stored in advance in the EEPROM 14 as a map indicating the relationship between the amplitude difference and the ground potential.

  When the vehicle control device 10 is actually used, the ground potential estimating unit 113 displays the ground potential corresponding to the amplitude difference obtained by the amplitude difference calculating unit on a map indicating the relationship between the amplitude difference stored in the EEPROM 14 and the ground potential. Estimate based on. In this way, by estimating the ground potential using the map, it is possible to perform estimation while suppressing the influence of individual differences due to component variations.

  Such a measurement of the relationship between the amplitude difference and the ground potential is performed by a shipping inspection device before shipment from the factory.

  The sensor value correcting unit 115 corrects the output voltage of the throttle position sensor 32 detected by the sensor value measuring unit 114 using the potential of the ground G2 estimated by the ground potential estimating unit 113. Since the potential of the ground G2 of the vehicle control device 10 is high, the output voltage of the throttle position sensor 32 is apparently measured only for the increase in the potential of the ground G2.

  Therefore, if the sensor value measuring means 114 adds the potential of the ground G2 estimated based on the dither amplitude 56 by the ground potential estimating means 113 to the output voltage of the throttle position sensor 32 detected by the sensor value measuring means 114. The correction is completed. By using the corrected sensor value for vehicle control, erroneous detection of a failure can be prevented even when the potential of the ground G2 is high.

  If the output voltage value of the throttle position sensor 32 after being corrected by the sensor value correction means 115 is abnormal, the failure detection means 117 in the vehicle control device 10 counts up a failure determination counter. On the other hand, when the output voltage value becomes a normal value, the failure detection means 117 clears the failure determination counter. The failure detecting means 117 determines that the throttle position sensor 32 has failed when the value of the counter becomes equal to or greater than a predetermined value.

  As described above, the vehicle control apparatus according to the first embodiment uses the corrected sensor output voltage based on the estimation result of the potential of the ground G2 as the sensor output voltage for performing the failure determination. Even when the value is high, no false detection of failure occurs. In this state, even when the sensor value becomes abnormal due to sensor disconnection or the like, failure detection by the failure detection means 117 is possible, and the driver can be notified of the failure.

  FIG. 6 is a flowchart showing a series of operations of the vehicle control device according to Embodiment 1 of the present invention. When the control is started, the dither amplitude measuring unit 111 measures the dither amplitude 56 in step S601. As an example, the dither amplitude measuring unit 111 stores a maximum value and a minimum value within a certain time (for example, twice the dither period 57), and obtains a difference between the maximum value and the minimum value, thereby obtaining a dither amplitude. 56 can be calculated.

  Next, in step S602, the amplitude difference calculation means 112 subtracts the dither amplitude 56 measured in the previous step S601 from the reference amplitude value stored in the EEPROM 14 before product shipment, and calculates the dither amplitude difference.

  Next, in step S603, the ground potential estimation means 113 determines the previous step S602 based on the relationship between the dither amplitude difference stored in the EEPROM 14 at the time of shipping inspection and the ground potential (corresponding to the relationship shown in FIG. 5). The potential of the ground G2 corresponding to the dither amplitude difference obtained in step 1 is estimated.

  Next, in step S604, the sensor value correcting unit 115 adds the potential of the ground G2 estimated in the previous step S603 to the output voltage of the throttle position sensor 32, thereby obtaining a corrected sensor value. .

  Next, in step S605, the failure detection unit 117 determines whether there is an abnormality in the sensor value. If the corrected sensor value is normal, the process proceeds to step S606, and the failure determination counter is cleared. On the other hand, if the corrected sensor value is abnormal, the failure detection means 117 proceeds to step S607 and counts up the failure determination counter.

  Further, in step S608, the failure detection unit 117 determines whether or not the failure determination counter is equal to or smaller than a predetermined set value. If it is equal to or greater than the predetermined set value, the failure detection unit 117 determines that a failure has occurred, and proceeds to step S609 to notify the driver of the failure via the failure notification unit 118. On the other hand, when the counter is equal to or smaller than the predetermined set value, the failure detection unit 117 determines that there is no failure and repeats the processing from step S601.

  As described above, according to the first embodiment, the ground potential is estimated from the dither amplitude even when the ground potential of the vehicle control device becomes high due to the operation of a device that consumes a large current, and according to the estimation result. Thus, it is possible to detect a failure by correcting the sensor value. As a result, even when a failure such as a sensor disconnection occurs in a state where the ground potential is high, failure detection based on the corrected sensor value can be performed, and the driver can be notified of the failure.

  Furthermore, by using the target current value based on the corrected sensor value for vehicle control, even when the ground potential is high, an operation equivalent to the control when the ground potential is not high can be performed. As a result, traveling as intended by the driver can be realized regardless of the state of the ground potential. Furthermore, since the failure detection is performed using the corrected sensor value, it is possible to avoid erroneous detection of the sensor failure due to the high ground potential.

  Furthermore, the amplitude of the dither current when the ground potential is 0 V is stored in advance as a reference amplitude, and the ground potential is estimated based on the amplitude difference from the measured dither amplitude, so that the amount of displacement from the reference value is obtained. The absolute value of the ground potential can be estimated, and the estimation accuracy of the ground potential is improved.

  Furthermore, at the time of shipment, etc., by measuring and storing in advance the reference amplitude value for each individual vehicle post-natal device, it is possible to suppress variations in the components of the amplitude difference for estimating the ground potential. In particular, the estimation accuracy of the ground potential is improved.

  Furthermore, at the time of shipment, for example, the relationship between the ground potential and the amplitude difference is mapped and stored in advance for each individual vehicle postnatal device, so that the relationship between the amplitude difference and the ground potential for estimating the ground potential can be determined. Variations in parts can be suppressed, and as a result, the estimation accuracy of the ground potential is improved.

It is the figure which represented typically the four-wheel drive vehicle which is a control object of the vehicle control apparatus in Embodiment 1 of this invention. It is the figure which represented typically the relationship between the hydraulic system of the four-wheel drive vehicle in Embodiment 1 of this invention, and a vehicle control apparatus. It is a detailed block diagram of the vehicle control apparatus in Embodiment 1 of this invention. It is the figure which showed the correspondence of the target current value after the dither correction | amendment in the steady state in Embodiment 1 of this invention, and the electric current of a proportional solenoid valve. It is a figure showing the relationship of the amplitude difference of a dither amplitude and a reference amplitude with respect to the electric potential of the ground in Embodiment 1 of this invention. It is a flowchart which shows a series of operation | movement of the vehicle control apparatus in Embodiment 1 of this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 Vehicle control apparatus, 11 CPU, 12 Drive circuit, 13 Current detection means, 14 EEPROM (memory means), 20 Hydraulic system, 21 Pump, 22 Motor, 23 Check valve, 24 Tank, 25 Accumulator, 26 Pressure sensor, 27 Proportional Solenoid valve, 28 relief valve, 31 engine, 32 throttle position sensor (various sensors), 41 transmission, 42 center differential, 43 front differential, 44 rear differential, 45 clutch, 46 front left wheel, 47 front right wheel, 48 rear left wheel, 49 Rear right wheel, 51 Target current value, 52 Dither correction amount, 53 Dither correction target current value, 54 Proportional solenoid valve current, 55 Average current value, 56 Dither amplitude, 57 Dither period, 111 Dither amplitude measuring means, 112 Amplitude difference calculation means, 113 g Land potential estimation means, 114 sensor value measurement means, 115 sensor value correction means, 116 target current value determination means, 117 failure detection means, 118 failure notification means, 119 dither correction means, 120 control means.

Claims (3)

In a vehicle control device that controls the vehicle by adjusting the opening of the proportional solenoid valve according to the detection values of various sensors mounted on the vehicle,
Ground potential estimation means for estimating the ground potential of the vehicle control device based on the amplitude of the dither current superimposed on the current value of the proportional solenoid valve;
Sensor value correction means for correcting detection values of the various sensors from the ground potential estimated by the ground potential estimation means;
Control means for adjusting the opening of the proportional solenoid valve based on detection values of various sensors after being corrected by the sensor value correction means;
A vehicle control device comprising: failure detection means for detecting abnormality of the various sensors based on detection values of the various sensors after being corrected by the sensor value correction means. The vehicle control device according to claim 1,
The ground potential estimating means includes
Storage means for preliminarily storing the dither current amplitude when the ground potential of the vehicle control device is 0 V as a reference amplitude;
Amplitude difference calculating means for obtaining an actual amplitude from the amplitude of the dither current superimposed on the current value of the proportional solenoid valve, and obtaining an amplitude difference between the reference amplitude and the actual amplitude stored in the storage means,
A vehicle control device that estimates a ground potential corresponding to the amplitude difference obtained by the amplitude difference calculation means. The vehicle control device according to claim 2,
The storage means further stores in advance a map that correlates an amplitude difference between a reference amplitude and an actual amplitude and a ground potential;
The vehicle control apparatus characterized in that the ground potential estimation means estimates a ground potential corresponding to the amplitude difference obtained by the amplitude difference calculation means based on the map stored in the storage means.

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