KR100795034B1 - Electronic control unit in electric power steering system - Google Patents

Abstract

Electronic control of the electric power steering system, which is easy to repair by storing changes of various system state variables in the electric power steering system of the electric power steering system and using it as a reference for analyzing the cause of the failure occurred at the present time. Relates to a device.

The electronic control device includes an electronic control device of an electric power steering system, comprising: a communication interface for transmitting and receiving data with an external device; An input interface unit for receiving a signal transmitted from an external vehicle speed sensor, a torque sensor, and a mode switch; An output interface unit for transmitting and receiving predetermined data with an external brushless motor, a motor position sensor, a warning lamp, a communication interface; A nonvolatile memory in which inspection data is periodically stored in a corresponding area in accordance with a predetermined control signal; Based on the parts state data input from the vehicle speed sensor and the torque sensor, the corresponding parts state of the vehicle is stored according to a predetermined period, and when the failure detail analysis request signal is received from the outside, the parts state data is stored from the nonvolatile memory. The control unit is configured to receive and analyze failure details of the corresponding parts and output failure details analysis data through the communication interface.

Description

Electronic control device of electric power steering system {ELECTRONIC CONTROL UNIT IN ELECTRIC POWER STEERING SYSTEM}             

1 is a block diagram showing the configuration of a general electric power steering system.

Figure 2 is a block diagram showing the detailed configuration of the electric power steering system according to the present invention.

3 is a block diagram illustrating in detail a memory map of the EEPROM of FIG. 2;

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

10: ECU 12: battery

14: mode switch 16: vehicle speed sensor

18: torque sensor 20: warning light

22: motor

The present invention relates to an electronic control device. In particular, the electronic control device of the electric power steering system stores changes of various system state variables in the past and utilizes them as a reference for analyzing the cause of the failure occurring at the present time. The present invention relates to an electronic control apparatus for an electric power steering system that facilitates the operation.

In general, an electric power steering (EPS) system is an apparatus that assists steering power by the power of an electric motor instead of the existing hydraulic pressure.

The configuration of such EPS is as follows.

FIG. 1 is a block diagram showing the configuration of a general EPS, including an electronic control unit (ECU) 10 for generating a predetermined control signal, and a battery 12 for supplying a predetermined level of DC power; A mode switch 14 for the driver to select the electric power steering mode by pressing the motor, a speed sensor 16 for detecting the speed of the vehicle, and a driver's steering intention Torque sensor 18 is connected to the input terminal of the electronic controller.

The output terminal of the electronic control device includes a warning lamp 20 for notifying the driver of a predetermined failure and a motor 22 for providing power for assisting the steering force of the vehicle.

Referring to the operation flow of the EPS as follows.

First, the driver's steering intention is detected through a torque sensor directly connected to the steering wheel. This signal is received by the ECU and assists steering by driving the motor to provide the appropriate force, taking into account the current vehicle speed. In other words, when stopping or driving at low speeds, the driver's power is reduced by substituting a large force.

The EPS is divided into a column type (Columm type), a pinion type (rack type), a rack type (Rack type) according to the position where the electric motor transmits the steering assistance force, the column type EPS is a column axis on which the steering wheel is mounted By connecting an electric motor, it is used in a light car or a small car, and the pinion type EPS directly assists the pinion of the rack and pinion to be used in a medium and small car, and the rack type EPS supports the rack bar of the rack and pinion directly and Used for large cars.

This electronic control device of EPS is 1) sensor signal input processing function, 2) motor current control, calculation function, 3) pulse width modulation (PWM) motor driving function, 4) fail-safe logic (FAIL) -SAFE LOGIC) function and consists of input interface circuit, output interface circuit and control circuit.

However, in the EPS system as described above, the past history is not considered at all with respect to the current failure. In other words, it only alerts you if the device has failed.

Thus, in order for the driver to develop a more comfortable and reliable system, there is a need to monitor the cause of the failure.

The present invention is to solve the above problems and to meet the above needs, the electronic control of the electric power steering system to facilitate troubleshooting by analyzing the cause of the failure on the basis of previously stored data at the time of failure, to inform the driver The purpose is to provide a device.

Features of the present invention for achieving the above object is a communication interface for transmitting and receiving data with an external device; An input interface unit for receiving a signal transmitted from an external vehicle speed sensor, a torque sensor, and a mode switch; An output interface unit for transmitting and receiving predetermined data with an external brushless motor, a motor position sensor, a warning lamp, a communication interface; A nonvolatile memory in which inspection data is periodically stored in a corresponding area in accordance with a predetermined control signal; Based on the parts state data input from the vehicle speed sensor and the torque sensor, the corresponding parts state of the vehicle is stored according to a predetermined period, and when the failure detail analysis request signal is received from the outside, the parts state data is stored from the nonvolatile memory. The control unit is configured to receive and analyze the failure details of the corresponding parts and output failure details analysis data through the communication interface.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

2 is a detailed block diagram of an electronic control apparatus for an electric power steering system according to the present invention, and includes an electronic control apparatus 10 for generating a predetermined control signal and supplying a DC voltage having a predetermined level to an input terminal thereof. The driver's steering intention is detected by detecting the battery 12, the mode switch 14 for the driver to select, the vehicle speed sensor 16 for detecting the speed of the vehicle, and the torque of the vehicle. Torque sensor 18 is connected.

In addition, a brushless direct current motor 220 for providing a predetermined power source is provided at an output end of the electronic controller 10, and a motor position sensor (hereinafter, referred to as a position sensor) for feeding back each position of the motor. 210 and a warning light 200 for informing a driver of a predetermined failure are connected to each other.

Meanwhile, the electronic controller 10 includes an input interface circuit 120 for receiving signals from the battery 12, the mode switch 14, the vehicle speed sensor 16, and the torque sensor 18, and the position. The sensor interface 210, an output interface circuit 150 for signal output and interfacing to the warning lamp 200, a motor driver 220 for applying a control signal for driving the BLDC motor 220, and a fault history EEPROM (Erasable Electronic Programmable Read Only Memory) 130 is recorded.

Here, the BLDC motor 220 will be described in detail as follows.

Since a conventional motor has a mechanical mechanism by a brush and a commutator, the generation of friction torque, poor contact due to wear and corrosion, noise and abrasion, etc. occur, and to solve this disadvantage, the brushless DC motor is a BLDC motor.

The memory map of the EEPROM, which is a main feature of the present invention, will be described in detail as follows.

FIG. 3 is a block diagram illustrating a memory map of the EEPROM shown in FIG. 2. The controller periodically stores the state of the vehicle in the EEPROM. Since the EEPROM can be stored from 00 to FF, the maximum number of times can be stored. Until the FFth.

Therefore, at 00, the state before n cycles is stored, and at FF, the state before n + 1 cycles is stored.

If the current state information to be stored corresponds to 12, state 10 before 2 cycles, state 11 before 1 cycle, state 12 before the current state, state 13 before the FF cycle, Address 14 will be stored in the order of state before FF-1 cycle.

In this case, the EEPROM is a kind of nonvolatile writable memory, and the memory area is not always determined to the FF address but can be selected according to an application.

In addition, the EEPROM performs the role of a black box by recording the current state while deleting the oldest record by repeating infinitely from the start address to the end address set in the EEPROM.

Based on the stored information, the electronic controller analyzes the cause of the failure and transmits the analyzed data to an external device through the communication interface.

For reference, the external device may facilitate the repair by informing the driver of a method for resolving a failure caused by receiving the analyzed data.

According to a preferred embodiment of the present embodiment as described above has the following advantages.

First, when a failure occurs, the cause of the current failure is analyzed and the failure analysis data is output based on the state information of the corresponding parts accumulated periodically in the past, thereby making it easy to repair and maintain the vehicle.

Second, by securing past data on replacement parts and frequent breakdowns of automobile parts, it is possible to implement preventive maintenance system by informing the novice driver of the maintenance technology that is being developed in real time.

Claims (1)

In the electronic control device of the electric power steering system, Communication interface for data transmission and reception with an external device, An input interface unit for receiving a signal transmitted from an external vehicle speed sensor, a torque sensor, and a mode switch; An output interface for transmitting and receiving a predetermined data with an external brushless motor, a motor position sensor, a warning light, a communication interface, A nonvolatile memory in which inspection data is periodically stored in a corresponding area in accordance with a predetermined control signal; Based on the component state data input from the vehicle speed sensor and the torque sensor, the corresponding component state of the vehicle is stored in the nonvolatile memory according to a predetermined period, and when a failure detail analysis request signal is received from the outside, the nonvolatile memory is stored in the nonvolatile memory. And a controller configured to receive the part status data and analyze failure details of the corresponding parts to output failure details analysis data through the communication interface.

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