KR20030055866A - A difficulty diagnosing and putting apparatus in eps system - Google Patents

Abstract

PURPOSE: A failure diagnosing and managing apparatus of an EPS(Electronic Power Steering) system is provided to prevent a misoperation of the EPS by installing diagnosing and deciding devices to an ECU(Electronic Control Unit) and taking necessary steps promptly. CONSTITUTION: A failure diagnosing and managing apparatus of an EPS(Electronic Power Steering) system includes a failure diagnosing and deciding device(8). The failure diagnosing and deciding device diagnoses and decides failure of the EPS system by monitoring torque of a torque sensor(2), a vehicle speed of a speed sensor(3) and a steering angle of a steering angle sensor(4). The failure diagnosing and deciding device turns off a motor relay of a motor relay on/off circuit(6) when failure is decided. The motor relay is turned on when detected information is returned to normal conditions. A main relay of a main relay on/off circuit(1) is turned off when serious failure is decided to turn off an ECU(Electronic Control Unit). Therefore, a misoperation of the EPS system is prevented previously by taking prompt steps.

Description

Fault diagnosis and countermeasures in electronically controlled power steering system {A DIFFICULTY DIAGNOSING AND PUTTING APPARATUS IN EPS SYSTEM}

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a device for diagnosing and correcting a failure in an electronic power steering system (hereinafter, referred to as "EPS"), and more particularly to an electronic control unit (hereinafter referred to as "ECU"). Fault Diagnosis and Determination Device in EPS System to prevent malfunction of EPS system by performing diagnosis of various failures and taking prompt action in case of failure. will be.

In general, the vehicle is provided with a vehicle ECU that receives the electrical signals detected by the various input sensors and outputs a digital control signal for driving the various actuators on the output side.

As shown in FIG. 1, the EPS system which reduces the operation force of the driver's steering wheel according to the speed of the vehicle by using the ECU as described above, enables the main relay to be turned on / off for driving the ECU. Main relay on / off circuit (1), torque sensor (2) for detecting steering wheel torque, vehicle speed sensor (3) for detecting vehicle speed, steering angle sensor for detecting steering angle of steering wheel (4) and when the main relay is turned on through the main relay on / off circuit 1, the motor is driven from the information detected by the torque sensor 2, the vehicle speed sensor 3, and the steering angle sensor 4, respectively. A target current calculator 5 for calculating a target current for driving the motor 7 and turning on the motor relay to drive the motor 7 so that the target current calculated by the target current calculator 5 becomes a real current flowing through the motor 7. Motor relay on / off circuit ( 6) consists of.

In the conventional EPS system configured as described above, the target current calculation unit 5 uses the torque sensor 2, the vehicle speed sensor 3, and the steering current sensor 5 to detect the torque, the vehicle speed, and the steering angle from the detected information. When the target current is calculated, the calculated target current is applied to the motor 7 to drive the motor 7.

On the other hand, the conventional EPS system operating as described above is very important to ensure the stability of the failure relative to the conventional hydraulic steering system as a steering system by the electronic control.

However, in the conventional EPS system, a device for diagnosing and determining a failure for various failures of the EPS system including an ECU and taking a corresponding measure when a failure occurs is not implemented.

Accordingly, when the EPS system malfunctions due to a failure, there is a problem that the driver handle does not operate according to the driver's intention or a dangerous situation may occur in which the steering wheel may be steered regardless of the driver's intention.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, the object of which is to provide a diagnosis and judgment means in the ECU to diagnose the various failures and if the failure occurs quickly by taking the appropriate steps step by step of the EPS It is to provide a failure diagnosis and countermeasure device in an EPS system that prevents malfunctions and promotes safe driving of a vehicle.

1 is a block diagram of a conventional electronically controlled power steering system,

2 is a block diagram of an apparatus for diagnosing and correcting a failure in an electronically controlled power steering system according to the present invention.

<Description of the symbols for the main parts of the drawings>

1: main relay on / off circuit 2: torque sensor

3: vehicle speed sensor 4: steering angle sensor

5: target current calculating unit 6: motor relay on / off circuit

7: motor 8: fault diagnosis and judgment unit

The fault diagnosis and countermeasure in the EPS system of the present invention for achieving the above object includes a main relay on / off circuit, a torque sensor, a vehicle speed sensor, a steering angle sensor, and the main relay on / off circuit. A target current calculator configured to calculate a target current for driving the motor from the information detected by the torque sensor, the vehicle speed sensor, and the steering angle sensor when the main relay is turned on, and a target calculated by the target current calculator by turning on the motor relay. An EPS system composed of a motor relay on / off circuit for driving a motor so that a current becomes an actual current flowing through the motor, the torque detected by the torque sensor, the vehicle speed detected by the vehicle speed sensor, and the steering angle detected by the steering angle sensor Monitoring each detection information to diagnose and determine the failure of EPS system, And further comprising a right that action fault diagnosis and determination takes is characterized in that configuration.

Hereinafter, with reference to the accompanying drawings will be described in detail the configuration and operation of the failure diagnosis and action apparatus in the EPS system according to the present invention.

FIG. 2 is a block diagram of a fault diagnosis and countermeasure device in an EPS system according to the present invention, which detects a main relay on / off circuit 1 and a handle torque for turning on / off a main relay for driving an ECU. The main relay is turned on via the torque sensor 2, the vehicle speed sensor 3 for detecting the speed of the vehicle, the steering angle sensor 4 for detecting the steering angle of the steering wheel, and the main relay on / off circuit 1 When the torque sensor (2), the vehicle speed sensor (3), the steering angle sensor (4), the target current calculation unit (5) for calculating a target current for driving the motor, and the motor relay is turned on A torque detected by the torque sensor 2 and the motor relay on / off circuit 6 for driving the motor 7 so that the target current calculated by the target current calculating unit 5 becomes the actual current flowing through the motor 7. , The vehicle speed detected by the vehicle speed sensor 3, the It is composed of a failure diagnosis and determination unit 8 for monitoring and detecting the detection information of the steering angle detected by the steering angle sensor 4 to diagnose and determine a failure of the EPS system and to take a corresponding action when a failure occurs.

When it is determined that a failure has occurred in the EPS system, the failure diagnosis and determination unit 8 turns off the motor relay of the motor relay on / off circuit 6 in a step 1 operation, and at this time within the predetermined time range. When the detection information of the torque sensor 2, the vehicle speed sensor 3, and the steering angle sensor 4 is normally returned, the motor relay of the motor relay on / off circuit 6 is turned on to generate normal steering force.

However, if it is determined that the failure in the EPS system is a serious failure, when the EPS relay is normally turned off by turning off the main relay of the main relay on / off circuit 1 as a two-stage action. Until steering is stopped.

Here, the same structure as the conventional one has been described with the same reference numeral.

Referring to the operation of the failure diagnosis and action device in the EPS system of the present invention configured as described above are as follows.

In the EPS system according to the present invention, when the main relay of the main relay on / off circuit (1) is turned on to drive the ECU, the torque sensor (2), the vehicle speed sensor (3), the steering angle sensor (4) Detects corresponding information of torque, vehicle speed, and steering angle, respectively, and outputs the detected information to the target current calculator 5.

Accordingly, the target current calculator 5 drives the motor 7 from the detected information of the torque, the vehicle speed, and the steering angle detected by the torque sensor 2, the vehicle speed sensor 3, and the steering angle sensor 4, respectively. Calculate the target current to

Thereafter, the motor relay on / off circuit 6 turns on the motor relay to drive the motor 7 so that the target current calculated by the target current calculating unit 5 becomes the actual current flowing through the motor 7.

On the other hand, the failure diagnosis and determination unit 8 detects each piece of detection information of the torque detected by the torque sensor 2, the vehicle speed detected by the vehicle speed sensor 3, and the steering angle detected by the steering angle sensor 4. By monitoring and diagnosing the failure of the EPS system, if a failure occurs, the corresponding action is taken.

That is, when monitoring the detection information of the torque sensor (2), the vehicle speed sensor (3), the steering angle sensor (4), it is determined that a failure has occurred in the EPS system, the motor of the motor relay on / off circuit (6) Take the equivalent of step 1 to turn off the relay.

At this time, when the detection information of the torque sensor 2, the vehicle speed sensor 3, the steering angle sensor 4 is normally returned within a predetermined time range, the motor relay of the motor relay on / off circuit 6 is turned on to normal. Generate steering force.

And, if it is determined that the failure in the EPS system is a serious level of failure, the main relay of the main relay on / off circuit 1 is turned off to completely turn off the ECU and stop generating steering force until the EPS system returns normally. Take the action corresponding to the steps.

In addition, in the present invention, when a failure occurs in the EPS system, a warning lamp such as a fail lamp may be turned on to notify the driver of the failure of the EPS system.

As described above, in the present invention, the detection information of each sensor is monitored to determine whether the EPS system is broken and the corresponding action is systematically phased according to the determined failure level of the EPS system.

In other words, by diagnosing and determining the failure of the EPS system in advance, it is possible to prevent the malfunction of the EPS system more reliably by taking an action in a short time.

As described above, the present invention is provided with a failure diagnosis and determination means in the ECU to diagnose various failures and to take steps step by step quickly when a failure occurs, thereby preventing malfunction of the EPS system in advance. It is possible to protect the vehicle as well as the driver by preventing lane departure of the vehicle due to sudden steering due to malfunction of the EPS system, thereby promoting safe driving of the vehicle.

Claims (2)

When the main relay is turned on through the main relay on / off circuit, the torque sensor, the vehicle speed sensor, the steering angle sensor, and the main relay on / off circuit, the information is detected from the torque sensor, the vehicle speed sensor, and the steering angle sensor, respectively. EPS consisting of a target current calculating unit for calculating a target current for driving the motor, and a motor relay on / off circuit for turning on the motor relay to drive the motor so that the target current calculated by the target current calculating unit becomes a real current flowing through the motor. In the system, Diagnose and determine the failure of the EPS system by monitoring the detection information of the torque detected by the torque sensor, the vehicle speed detected by the vehicle speed sensor, and the steering angle detected by the steering angle sensor, and take a corresponding action when a failure occurs. Failure diagnosis and action device in an electronically controlled power steering system, characterized in that it further comprises a failure diagnosis and determination unit. The method of claim 1, wherein the failure diagnosis and determination unit, A first step of determining whether the EPS system is broken by monitoring detection information of the torque sensor, the vehicle speed sensor, and the steering angle sensor; A second step of turning off the motor relay of the motor relay on / off circuit when it is determined that a failure occurs in the EPS system as a result of the determination of the first step; A third step of turning on the motor relay of the motor relay on / off circuit when the detection information of the torque sensor, the vehicle speed sensor, and the steering angle sensor is normally returned within a predetermined time range after performing the second step; As a result of the determination in the second step, if it is determined that the failure in the EPS system is a serious failure, steering power is generated until the main system of the main relay on / off circuit is turned off to completely turn off the ECU and the EPS system returns normally. And a device for diagnosing and correcting a failure in an electronically controlled power steering system, characterized in that it operates in a fourth step of stopping.