KR100412701B1 - Method of controlling trouble for throttle position sensor in an engine for vehicles - Google Patents

Abstract

For the purpose of preventing the engine starting from turning off due to lack of air quantity and fuel quantity in the case of failure of the throttle position sensor;

When the throttle position sensor breaks down, a signal of the HFM (air flow sensor) detects the state of the engine deceleration and acceleration so that the fuel compensation control is performed. do.

Description

METHOOD OF CONTROLLING TROUBLE FOR THROTTLE POSITION SENSOR IN AN ENGINE FOR VEHICLES}

The present invention relates to an engine control method for a failure of a throttle position sensor applied to an intake cylinder of an automobile engine, and more specifically, to detect a state of deceleration and acceleration of an engine as a signal of an air flow sensor when a throttle position sensor fails. The present invention relates to an engine control method in the event of a failure of a throttle position sensor of an automobile engine, in which fuel compensation control is performed.

For example, an engine used as a power source of an automobile receives fuel and air into a combustion chamber and compresses and explodes it, thereby reciprocating the piston up and down, and converting its up and down reciprocating motion into a rotational motion as a crank mechanism to obtain rotational power.

In such an automobile engine, a throttle position sensor is applied to an intake cylinder for introducing intake gas into the combustion chamber when the driver presses the accelerator pedal to detect the opening angle of the throttle valve that controls the opening area of the intake cylinder.

Accordingly, the electronic control unit that controls the engine as a whole controls the engine control by comparing the current operating state of the engine by combining the detection signals of the throttle position sensor as one element and combining the detection signals of the other sensors. Will be implemented.

Therefore, the throttle position sensor is one of the most important components in the automobile engine operated by the electronic control system. However, the throttle position sensor has almost no failure rate and, if a failure occurs, electrically connects the throttle position sensor and the electronic control unit. As a result of disconnection of wires, conventionally, there is no means provided in preparation for the failure of the throttle position sensor.

Accordingly, in the conventional case, when the throttle position sensor breaks down, the output voltage of the throttle position sensor is represented by "0" volts. When the air volume is compensated, the air volume of the dashpot must appear as "0". This implies that a drop in engine speed (DROP) is caused.

In addition, when the signal of the throttle position sensor is displayed as "0" volts, the fuel correction amount is "0", so that the air amount and fuel amount due to the sudden opening and closing of the throttle valve are not compensated for, so that the engine always There is a problem that a drop in the number of revolutions occurs, and in particular, the engine is turned off when the load is severe.

Therefore, the present invention has been invented to solve the above problems, an object of the present invention is to detect the state of the deceleration and acceleration of the engine as a signal of the air flow sensor when the throttle position sensor breakdown so that the fuel compensation control is made An engine control method is provided when a throttle position sensor of an automobile engine fails.

1 is a block diagram of a control system for operating the present invention.

2 is an operational flowchart of a control method according to the present invention;

3 is a view showing a state in which fuel is controlled by the present invention.

4 is an operation flowchart of a conventional control method.

In order to realize this, the present invention includes a first step of determining whether the engine is a high load region based on the cooling water temperature and the intake temperature, if it is determined that the disconnection is determined according to whether there is an input signal from the throttle position sensor;

If it is determined in the first step that the engine is a high load region, a second step of reading and filtering an HFM signal and calculating a compensation air amount based on the HFM signal;

A third step of calculating an amplitude of the HFM signal read in the second step, calculating an amplitude change amount of the HFM signal with respect to the calculated amplitude, and determining whether the amplitude change amount of the HFM signal is greater than a first reference value Wow;

If it is determined in the third step that the amplitude variation of the HFM signal is greater than the first reference value, the filtered HFM signal variation is calculated, and if it is determined that the filtered HFM signal variation is greater than the second reference value, the acceleration is determined to be acceleration. A fourth step of performing a correction;

If it is determined in the third step that the amplitude change amount of the HFM signal is smaller than the first reference value, it is determined whether the amplitude change amount is smaller than the third reference value, and if it is small, the filtered HFM signal change amount is calculated, and the filtered HFM signal change amount is calculated. The engine control method when the throttle position sensor failure of the vehicle engine, characterized in that the fifth step of performing a fuel correction with the deceleration fuel amount is determined as the deceleration is determined to be smaller than the fourth reference value.

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

1 is a block diagram of a control system capable of operating the present invention. As an input means, a throttle position sensor 2 for detecting an opening amount of a throttle valve and an air flow sensor 4 for detecting an intake air amount of an intake cylinder are shown. (Hot Film Type Air Flow Sensor, hereinafter referred to as HFM), engine rpm sensor 6 for detecting engine speed, vehicle speed sensor 8 for detecting vehicle speed, cooling water temperature sensor 10 for detecting cooling water temperature, and And an intake air temperature sensor 12 for detecting the temperature of the intake air.

The input means in the above is not limited to the above sensors, but describes only the minimum sensors for operating the present invention.

In addition, the signals input from the input means are compared with the data pre-inputted by the electronic control unit ECU to control fuel compensation according to acceleration and deceleration through the fuel control unit 14.

The fuel control unit 14 means a fuel injector for injecting fuel, and the fuel amount can be controlled by controlling the energization time of the fuel injector.

In the control method of the present invention using such a system, as shown in FIG. 2, it is first determined whether there is an input signal from the current throttle position sensor (S100).

If it is determined in step S100 that the throttle position valve is in a disconnected state, the cooling water temperature and intake temperature are read from the cooling water temperature sensor 10 and the intake air temperature sensor 12 (S110), and based on this, it is determined whether the engine is a high load region. It is made (S120).

In the above-mentioned high load region, the cooling water temperature is set to 90 ° C. or higher, and the intake air temperature is set to 70 ° C. or higher.

If it is determined in step S120 that the engine is a high load region, the HFM signal is read (S130), and then filtered (S140), and the amount of compensation air is calculated based on this (S150).

The larger the filtered HFM signal is, the larger the amount of compensation air is set.

The amplitude of the HFM signal is calculated (S160), and the amplitude thereof is calculated in units of 100 msec, and after calculating the amplitude change amount (ΔFRQ) of the HFM signal with respect to the calculated amplitude (S170), the amplitude of the HFM signal. It is determined whether the change amount ΔFRQ is greater than the first reference value threshold 1 (S180).

The amplitude change amount ΔFRQ of the HFM signal is calculated in units of approximately 100 msec, and when the throttle valve is changed, the amplitude difference of the HFM signal is used. In this case, when the throttle is constant, the HFM signal is constant, but the throttle is sudden. The amplitude fluctuates rapidly, as shown in the upper part of FIG.

In addition, if it is determined in step S180 that the amplitude change amount ΔFRQ of the HFM signal is greater than the first reference value threshold 1, the filtered HFM signal change amount ΔF_hfm is calculated (S190), and the filtered HFM signal change amount is determined. If (ΔF_hfm) is greater than the second reference value (threshold 2) is determined (S200) is determined to be large, it is determined to be accelerated (S210) and the acceleration fuel amount correction is performed (S220).

When it is determined that the acceleration through the above process, as shown in FIG. 3, the fuel is gradually increased and then attenuated by a constant slope.

At this time, the accelerated fuel amount becomes the base fuel amount + the accelerated fuel amount compensation.

If it is determined in step S180 that the amplitude change amount ΔFRQ of the HFM signal is smaller than the first reference value (threshold 1), it is determined whether the amplitude change amount ΔFRQ of the HFM signal is smaller than the third reference value (threshold 3) ( S230) If it is determined that it is determined, the filtered HFM signal variation amount ΔF_hfm is calculated (S240), and it is determined whether the filtered HFM signal variation amount ΔF_hfm is smaller than the fourth reference value (threshold 4) (S250). If it is determined that the deceleration (S260), after the deceleration fuel amount correction is performed (S270) to end.

When the step S200 and step S250 are not satisfied as described above, when it is determined to be decelerated through the above process, as shown in FIG.

At this time, the deceleration fuel amount is the basic fuel amount + deceleration fuel amount compensation.

As described above, according to the present invention, when the throttle position sensor breaks down, the engine deceleration and acceleration are detected as signals of the HFM (air flow sensor) so that the fuel compensation control is performed so that the air volume of the dash port is not started. This invention is an invention that can prevent the engine starting off due to the lack of acceleration / deceleration fuel amount due to this off or acceleration / deceleration determination impossible, thereby contributing to safe driving.

Claims (4)

A first step of determining whether the engine is a high load region based on the cooling water temperature and the intake air temperature, if it is determined that the disconnection is determined according to whether there is an input signal from the throttle position sensor; If it is determined in the first step that the engine is a high load region, a second step of reading and filtering an HFM signal and calculating a compensation air amount based on the HFM signal; A third step of calculating an amplitude of the HFM signal read in the second step, calculating an amplitude change amount of the HFM signal with respect to the calculated amplitude, and determining whether the amplitude change amount of the HFM signal is greater than a first reference value Wow; If it is determined in the third step that the amplitude variation of the HFM signal is greater than the first reference value, the filtered HFM signal variation is calculated, and if it is determined that the filtered HFM signal variation is greater than the second reference value, the acceleration is determined to be acceleration. A fourth step of performing a correction; If it is determined in the third step that the amplitude change amount of the HFM signal is smaller than the first reference value, it is determined whether the amplitude change amount is smaller than the third reference value, and if it is small, the filtered HFM signal change amount is calculated, and the filtered HFM signal change amount is calculated. The engine control method when the throttle position sensor failure of the vehicle engine, characterized in that the fifth step of performing a fuel correction with the deceleration fuel amount is determined as deceleration if it is determined to be smaller than the fourth reference value. The engine control method according to claim 1, wherein the high load region in the first step has a cooling water temperature of 90 ° C. or higher and an intake air temperature of 70 ° C. or higher. The method of claim 1, wherein in the fourth step, the fuel correction is performed by a predetermined amount of fuel and gradually attenuated by a predetermined slope. The method of claim 1, wherein in the fourth step, the fuel correction is performed by gradually reducing the amount of fuel and then gradually recovering it to a constant inclination.