KR20100010546A - Device and method for a controlling automobile using both gasoline and lpg - Google Patents

Abstract

PURPOSE: A fuel supply control apparatus for a vehicle using both gasoline and LPG and a control method thereof are provided to easily detect malfunction reason by informing malfunctions such as short circuit or open circuit of a signal wire of a solenoid valve of a user. CONSTITUTION: A fuel supply control apparatus for a vehicle using both gasoline and LPG comprises an LPG ECU(Electric Control Unit,30). The LPG ECU comprises a voltage regulator(31), an overvoltage sensor(32), a gasoline connection controller(35), an LPG controller(36), a central processing unit(34), and a CAN bus transmitter(37). The voltage regulator adjusts the voltage inputted by the ignition key of the input unit. The overvoltage sensor senses and removes overvoltage outputted from the voltage regulator. The gasoline connection controller and the LPG controller connect or disconnect a gasoline fuel system or an LPG fuel system by input value. The central processing unit controls each component. The CAN bus transmitter transmits data to the central processing unit.

Description

Fuel supply control device and control method for gasoline and LP combined vehicles {DEVICE AND METHOD FOR A CONTROLLING AUTOMOBILE USING BOTH GASOLINE AND LPG}

The present invention relates to a fuel supply control device and a control method for a gasoline and LPG combined vehicle, it is possible to reset the program stored in the LPG ECU by using CAN communication, it is possible to control according to the state of the vehicle by setting various control conditions The present invention relates to a fuel supply control device and a control method for a gasoline and LPG combined vehicle.

In general, LPG (Liuefied Petroleum Gas) fuel among the fuels used in the vehicle is used in some passenger cars and vans because of its high octane value, excellent heat resistance, and low fuel cost.

LPG fuel supplied to the engine of the vehicle is a liquid phase and when it is vaporized, it has a good mixing property with air and thus flammability, so knocking is less likely to occur than gasoline and diesel. Vapor-Lock or percolation It is possible to prevent the occurrence of such a phenomenon, and the application range is gradually increasing as an alternative fuel of gasoline or diesel fuel.

Therefore, a gasoline and LPG combined vehicle has a vaporizer and a mixer that requires the use of LPG fuel, a mixer and an LPG fuel tank, a solenoid valve that controls the supply of LPG fuel, and an LPG ECU that controls the solenoid valve. Controller Unit) must be provided.

In a conventional gasoline and LPG combined vehicle, starting is performed by gasoline fuel and when a predetermined condition is satisfied after starting gasoline, for example, a predetermined time has elapsed after starting, and the engine coolant temperature has become above a certain temperature. When the fuel is provided to automatically convert from gasoline to LPG, the technology for the engine supply control device of the combined gasoline and LPG vehicle is well shown in the Republic of Korea Patent Application No. 1999-025086.

The fuel supply control device for a conventional gasoline and LPG combined vehicle as described above is provided with a fuel line that is configured to switch fuel from an external throttle position sensor, an oxygen sensor, a coolant temperature sensor, and the like, and is not injected when the fuel is switched. A separate relay is provided for blocking, but when a problem such as a bug or an error occurs in a program previously stored in the LPG ECU, it is difficult to diagnose the failure, thereby increasing the repair cost.

That is, the conventional LPG ECU does not have a diagnostic function for the failure, it is not easy to determine the failure site of the system, and because the user can not give information about the failure site and diagnosis name, there was a lack of A / S, Because the stored program cannot be updated, it is impossible to improve functions and fix bugs of the program, and the fuel injection quantity control logic is not diverse, which does not satisfy the environmental regulations, and the response speed by the user's operation is slowed and the output is low. There was a problem such as hurting the quality of the sensitivity and poor commerciality.

The present invention has been made in order to solve the above problems, when a bug, error, etc. of the program previously stored in the LPG ECU, the fuel supply of the gasoline and LPG combined vehicle that can be upgraded or reinstalled by using can communication It is an object to provide a control device and a control method.

Another object of the present invention is to provide a user with a diagnosis of a fault such as an overvoltage and a signal line short circuit or an opening of a solenoid valve to notify a user, and thus a fuel supply control device and control method for a gasoline and LPG combined vehicle that can easily find the cause of the fault. To provide.

It is still another object of the present invention to provide a fuel supply control apparatus and control method for a gasoline and LPG combined vehicle that can eliminate the effects of noise and noise when each input signal is branched and input to the vehicle ECU and the LPG ECU. There is.

Still another object of the present invention is to provide a fuel supply control apparatus and control method for a gasoline and LPG combined vehicle that can increase the responsiveness of a vehicle driving corresponding to a user's operation by specifically diversifying control logic when using an LPG fuel gauge. To provide.

In order to achieve the above object, the present invention provides an input unit for outputting an input value of the state information data of the vehicle, a vehicle ECU for controlling the output amount of gasoline and LPG injected into the engine with the state information data using a pre-stored program ( A fuel supply control apparatus for a gasoline and LPG combined vehicle including an engine control unit) and an LPG ECU, a gasoline fuel gauge and an LPG fuel gauge for injecting fuel into an engine under control of the vehicle ECU and the LPG ECU, the LPG ECU The gasoline controller may include a voltage regulator for adjusting a voltage input by an ignition key of the input unit, an overvoltage detector for detecting and removing an overvoltage of a voltage output from the voltage regulator, and an input value for selecting fuel injected into an engine. Gasoline connection controller and LPG controller connected or disconnected with fuel gauge and LPG fuel gauge The air from the outside of the central processing unit and the LPG ECU for controlling the respective components, characterized in that it comprises a canvas transmitter provided to transmit data to the central processor.

The LPG ECU may further include a first relay driven to output oxygen amount data input from the input unit to the LPG ECU or the vehicle ECU.

The gasoline connection controller may further include: a second relay configured to selectively connect the gasoline injector of the gasoline fuel system and the vehicle ECU; An equivalent resistance to replace the gasoline injector with the same resistance as the gasoline injector if the gasoline injector and the vehicle ECU are not connected by driving of the second relay; And a third relay selectively connecting the gasoline pump and the vehicle ECU.

The LPG controller may further include: a solenoid valve controller controlling opening and closing of the solenoid valve with a PWM control signal calculated by a program of the central processing unit; And a solenoid valve state diagnosis unit for detecting a short circuit or opening of the solenoid valve and outputting a feedback signal to the central processing unit.

The present invention provides a method comprising: a first step of resetting a program using can communication when data input from an external gasoline and LPG combined vehicle matches data of a central processing unit of an LPG ECU; A second step of initializing state information of the vehicle and receiving data of a switch module for selecting fuel when mismatching or resetting is completed in the first step; When the data of the switch module is in gasoline mode, the solenoid valve is closed, and the vehicle ECU, the oxygen sensor and the gasoline fuel gauge are connected to perform fuel supply control using gasoline, and the data of the switch module is in the LPG mode. The vehicle ECU, the oxygen sensor and the gasoline fuel gauge are released, the solenoid valve is opened to perform fuel supply control using the LPG. When the data of the switch module is in the automatic mode, the gasoline mode is entered until the vehicle enters the deceleration section. And entering the deceleration section, and performing a LPG mode control.

In addition, the fuel supply control using the LPG, when the vehicle state information enters the predetermined coolant temperature, the throttle valve opening amount, the acceleration section, the deceleration section, the engine RPM conditions, characterized in that for performing the control according to the state information It is done.

In addition, when the coolant temperature is less than a predetermined temperature, the fuel injection amount is controlled by the PWM duty corresponding to the coolant temperature.

The throttle valve opening amount may be set to a low section for a case where the engine is idle, a middle section for a partial throttle valve opening, and a high section for a throttle valve opening to a maximum section. In order to control the fuel injection amount by the PWM duty calculated by the proportional integral control by receiving the data of the oxygen sensor, in the high section receives the engine RPM through the taco signal, PWM corresponding to the preset engine RPM The fuel injection amount is controlled by the duty.

The proportional integral control gain of the lower section is smaller than the proportional integral control gain of the intermediate section.

In addition, the acceleration section entering the intermediate section from the low section controls the fuel injection amount by the PWM duty set in the acceleration section for a predetermined time, the deceleration section entering the low section from the intermediate section is the engine The fuel injection amount is controlled by the PMW duty set in the deceleration section until the RPM reaches a preset reference engine RPM.

Here, the PWM duty set in the acceleration section is greater than the PWM duty set in the deceleration section.

In addition, when the engine RPM is received through the taco signal, and the engine RPM is a preset maximum engine RPM, the PWM duty is set to 0 to stop the fuel supply.

In addition, the fuel supply control using the LPG is performed by receiving the state information periodically, respectively, before the fuel supply control using the LPG is characterized in that the previous control is released.

In addition, the fuel supply control using the LPG is characterized in that it is repeatedly performed according to the state information until the data of the switch module is switched to the gasoline mode.

As described above, the present invention having the configuration as described above provides a user with a diagnosis of a fault such as an overvoltage and a signal line short circuit or opening of a solenoid valve in a fuel supply device of a gasoline and LPG combined vehicle using gasoline and LPG as fuel. By providing a notification, the cause of the failure can be easily found, and by selectively providing a signal that the vehicle ECU can detect as an error, the diagnosis of the vehicle ECU can be minimized, and each input signal is connected to the vehicle ECU and the LPG. It is possible to remove the effects of noise and noise when branching to the ECU and input.In the case of a bug or error of a program previously stored in the LPG ECU, upgrade or reinstallation of the program can be performed using CAN communication. Vehicle that responds to user's operation by specifically diversifying control logic when using LPG fuel gauge It is possible to increase the agreed reactive, can achieve effects such that by setting the point in time when the fuel is switched to deceleration to minimize noise and vibration of the fuel conversion user feels.

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

1 is a block diagram schematically showing the configuration of a fuel supply control apparatus for a gasoline and LPG combined vehicle according to the present invention. As shown in FIG. 1, a fuel supply control apparatus for a gasoline and LPG combined vehicle includes an input unit 10, an LPG ECU 30, an output unit 50, and a vehicle ECU 70.

Here, the fuel supply control apparatus according to the present invention means only the LPG ECU 30, and also illustrates the input unit 10, the output unit 50 and the vehicle ECU 70 to explain the operation of the LPG ECU 30. do.

The input unit 10 includes an ignition key 11, a switch module 13, a sensing unit 15, and an external device 17, and each component 11 of the input unit 10 except for the external device 17. 13, 15, and 17 are connected to the LPG ECU 30 and the vehicle ECU 70, respectively.

That is, the state information of the vehicle sensed by the input unit 10 is branched so that the LPG ECU 30 as well as the vehicle ECU 70 can be input.

The ignition key 11 among the components of the input unit 10 described above is supplied with data of the ignition key 11 when the user inserts the key into the key box and turns it to the IGN position to start the engine. The vehicle start information is informed to the LPG ECU 30 and the vehicle ECU 70, respectively.

In addition, the switch module 13 includes an input means 13a for receiving a user input and a display means 13b for outputting the remaining amount of LPG fuel to a user, wherein the input means 13a uses an engine using gasoline. Each switch is provided for the gasoline mode for driving the engine, the LPG mode for driving the engine using the LPG, and the automatic mode in which the supply of gasoline and the LPG is automatically controlled according to the vehicle condition.

In addition, the sensing means 15 is an input value for controlling the amount of fuel injected into the engine, and is connected to the coolant sensor 15a for detecting the coolant temperature and the accelerator pedal, and is opened to adjust the air flow rate according to the angle of the accelerator pedal. A throttle position sensor 15b for detecting the throttle valve opening amount is included.

Here, the throttle position sensor (TPS: THROTTLE POSITION SENSOR, 15b) reads the opening degree (opening and closing angle) of the throttle valve as a change in the output voltage according to the change of the variable resistor rotating along with the throttle shaft of the throttle body. 30) and the vehicle ECU 70 to control the fuel injection amount, the LPG ECU 30 and the vehicle ECU 70 in accordance with the output voltage of the throttle position sensor 15b and the pressure signal such as the engine speed, the engine state To determine the fuel injection amount.

In addition, the sensing means 15 includes an oxygen sensor 15c which checks whether the engine RPM input through the taco signal and the amount of fuel supplied are excessive.

Here, the oxygen sensor 15c checks the result of controlling the ignition timing and fuel injection amount of the engine in the LPG ECU 30 and the vehicle ECU 70, and the amount of oxygen remaining in the exhaust gas that is burned and discharged in the combustion chamber. Is compared with the amount of oxygen in the atmosphere and provides a basis for whether or not the amount of fuel currently supplied to the engine is at the theoretical air-fuel ratio.

In addition, the external device 17 refers to a device capable of performing a reset, such as initialization, modification and upgrade of the program stored in the LPG ECU 30 according to the present invention through can communication.

Meanwhile, the LPG ECU 30 according to the present invention includes a voltage regulator 31, an overvoltage detector 32, a first relay 33, a central processing unit 34, a gasoline connection controller 35, and an LPG controller 36. And a CAN bus transmitter 37.

Here, the voltage regulator 31 adjusts the voltage of the power supplied by the ignition key, and the overvoltage detector 32 is output through the voltage regulator 31 so that the voltage input to the CPU 34 is overvoltage. Diagnosis of cognition is provided to prevent this.

In addition, the first relay 33 is provided to connect the oxygen sensor 15c to the LPG ECU 30 or the vehicle ECU 70, because the reason is that when the fuel supply control is the LPG mode, the oxygen sensor 15c If the output of the) is also output to the vehicle ECU 70, the vehicle ECU 70 does not supply gasoline fuel, and thus it may be determined as an error, and accordingly, the vehicle ECU 70 may determine the failure. Because there is.

Accordingly, the first relay 33 is connected between the oxygen sensor 15c and the central processing unit 34 of the LPG ECU 30 and between the oxygen sensor 15c and the vehicle ECU 70, and the oxygen sensor in the gasoline mode. The connection between the 15c and the central processing unit 34 of the LPG ECU 30 is released. In contrast, the connection between the oxygen sensor 15c and the vehicle ECU 70 is released in the LPG mode.

Since the output data of the switch module 13 and the respective output data of the sensing means 15 are branched and input to the vehicle ECU 70 and the LPG ECU 30, noise, interference, etc. due to signal branching are input. In order to prevent this, in the present invention, by setting the impedance at the branch line of the switch module 13 and the sensing means 15 to minimize the disturbance of the signal, thereby reducing the control error due to noise, interference, etc. Minimize.

In other words, since the respective output data of the switch module 13 and the sensing means 15 are also input to the vehicle ECU 70 and also to the LPG ECU 30 in parallel, noise due to signal branching may occur. In other words, maximizing the resistance to reduce this reduces the current and minimizes the disturbance of the signal.

In addition, the CAN bus transmitter 37 connects the central processing unit 34 and the external device 17 by can communication to input data from the external device 17 to the central processing unit 34, and to store the built-in program. Allows resetting such as fixing errors, bugs, or upgrading the program according to the control logic.

In addition, the gasoline connection controller 35 includes a second relay 35a, an equivalent resistor 35b, and a third relay 35c, and connects or connects the vehicle ECU 70 and the gasoline fuel gauge 51. It is provided to be released.

Here, the second relay 35a and the third relay 35c are driven to connect the central processing unit 34 and the gasoline fuel gauge 51 or to connect the equivalent resistor 35b. Since the ECU 70 does not have to control the gasoline fuel gauge 51, the connection thereof is released. When the gasoline mode is in the gasoline mode, the ECU 70 is driven to connect the gasoline fuel gauge 51.

In addition, when the equivalent resistance 35b is connected to the second relay 35a and is in the LPG mode, the vehicle ECU 70 may not detect the disconnection from the gasoline fuel gauge 51. It is provided with the resistance element which has the same resistance value as the gasoline injector 51a.

The reason is that when the vehicle ECU 70 detects the disconnection from the gasoline injector 51a, since it may be regarded as a failure and an error may occur, the vehicle ECU 70 is equivalent to the equivalent resistance 35b having the same resistance as the gasoline injector 51a. To replace it.

The third relay 35c described above is connected between the gasoline pump 51b and the central processing unit 34, and in the LPG mode, the relay is turned off to release the connection, and in the gasoline mode, the relay is turned on to turn on the vehicle ECU. The 70 and the gasoline pump 51b are connected.

On the other hand, the LPG controller 36 is provided to control the LPG fuel gauge 53 to adjust the amount of LPG injected into the engine, and includes a solenoid valve controller 36a and a solenoid valve state diagnostic 36b.

Here, the solenoid valve controller 36a is provided to transmit a PWM signal corresponding to the fuel amount according to the PWM duty output from the central processing unit 34 to the solenoid valve 53, and the solenoid valve state diagnosis unit 36b is each Open or closed state (OPEN, SHORT) of the solenoid valve is provided to detect the normal or failure state to feed back to the central processing unit (34).

At this time, the solenoid valve state diagnostic 36b is provided to detect the opening or short circuit of the solenoid valve 53, it is also preferable to output the fault data for the user when the solenoid valve 53 is open, short.

The signal is input periodically to the solenoid valve state diagnosis unit 36b, and the central processing unit 34 detects whether the signal line is shorted or opened. Will output

In addition, the output unit 50 includes a gasoline fuel gauge 51 and an LPG fuel gauge 53, and the gasoline fuel gauge 51 includes a gasoline injector 51a and a gasoline pump 51b, and LPG The fuel gauge 53 includes a solenoid valve 53.

Here, the gasoline fuel meter 51 is controlled by the vehicle ECU 70 when the output data of the switch module 13 is in the gasoline mode, and the LPG ECU 30 is connected to the gasoline fuel meter 51 through the input unit 10. It only takes care of the connection between the vehicle ECU 70 and does not control the gasoline fuel gauge 51.

In addition, the gasoline pump 51b is provided for supplying fuel injected by the gasoline injector 51a to the engine, and is connected to the third relay 35c so that the gasoline pump 51b is connected to the vehicle ECU through the LPG ECU 30. 70), and the connection is released in the LPG mode.

In addition, the LPG fuel system 53 includes a solenoid 53a, and one of the plurality of solenoids 53a receives a PWM signal for fuel injection amount control from the solenoid valve controller 36a to control opening and closing.

That is, the solenoid valve 53 is opened and closed to block or supply the liquid or gaseous LPG based on each output data of the sensing means 15 in order to improve the startability of the LPG engine.

Therefore, the fuel supply control device according to the present invention can be reset, such as bugs, error correction or upgrade of the program through the can communication, it is possible to use a device for diagnosing the opening and short circuit of the solenoid valve, the overvoltage detector It can be used to detect and prevent overvoltage input to LPG ECU.

2 is a flow chart schematically showing a fuel supply control method for a gasoline and LPG combined vehicle according to the present invention. The fuel supply control method of the gasoline LPG combined vehicle according to the present invention starts with determining whether the ignition key is turned on to supply power and drive the engine (S10).

After the power of the battery is delivered to each component by supplying the ignition key in step S10, the LPG ECU asks whether to reset or modify a previously stored program using the CAN communication. (S11).

Here, when the external device and the CPU are connected to each other through the CAN bus transmitter for resetting, the external device transmits the CAN ID and the data ID to the CAN bus transmitter, and the CPU matches the CAN ID and the data ID. Check it.

Then, when the CAN ID and the data ID match, as a result of the check of the central processing unit, the user may input a desired program, or may upgrade the program or reset the error or bug in the program (S13).

If there is no external input through the can communication transmitter or the can ID and data ID do not match in step S11, the CPU determines that the user wants to reset and detects to implement the fuel supply control method. All input values in the means are initialized (eg, RESET (0)) (S15).

In the LPG ECU, the mode (input unit data) set by the user is read from the switch module (S19), and each control logic is entered according to the mode set by the user.

First, when the gasoline mode is set (S20), since the LPG fuel gauge is not necessary, the solenoid valves are all closed and the first ECU, the second relay, and the third relay are driven to connect the vehicle ECU, the oxygen sensor, and the gasoline fuel gauge. (S23).

Then, the gasoline fuel supply control is performed (S25), but the gasoline fuel supply control is not described in detail because it is not a control method according to the present invention.

On the other hand, when the LPG mode is set (S30), since the gasoline fuel gauge is not necessary, the first ECU, the second relay, and the third relay are driven to release the vehicle ECU, the oxygen sensor, and the gasoline fuel gauge (S31).

In addition, the solenoid valve for supplying LPG to the engine is opened (S33), the duty is calculated according to each input value received from the sensing means, and the PWM control for controlling the fuel injection amount is performed to control the LPG fuel supply (S35). ).

In addition, in the automatic mode (S40), in order to determine whether to use fuel as gasoline or LPG according to the state of the vehicle, first, each input value of the sensing means is an initial value (for example, a RESET state). (0)) (S41).

The reason is that in the automatic mode, the engine is controlled to the gasoline mode when the engine is driven, and since the logic is changed to the LPG mode in the deceleration section, when each input value is the initial value, the gasoline mode is entered (S43), If each input value is not the initial value, the flow enters the LPG fuel supply control (S35) step.

Then, when each input value is the initial value, when the gasoline mode control (S43) is completed, the input value is updated (S45) to check whether or not the entry into the deceleration section (S47).

This is because the vibration transmitted to the user due to inertia is large in the deceleration section, so even if the fuel supply source is changed, the haptic change felt by the user can be minimized.

Therefore, when entering the deceleration section (S47), to return to the step (S31) to be driven in the LPG mode to perform the fuel supply control according to the present invention, if the entry into the deceleration section (S47), deceleration The gasoline mode is controlled until the section is entered.

Here, the gasoline mode refers to the control logic including all of the steps (S21, S23, S25), LPG mode refers to the control logic including all of the steps (S31, S33, S35), automatic mode means steps (S41, S43) , S45, S47).

Therefore, when each input value is the initial value in the step S41, since the setting such as the solenoid valve closing (S21), the vehicle ECU and the oxygen sensor, and the connection of the gasoline fuel gauge (S23) is required, the gasoline mode (S21) is required. , S23 and S25, and when the input values of the step S41 are not initial values, the setting of the steps S31 and S33 is completed through the deceleration section S47, so that LPG fuel is supplied. It is possible to directly enter the control step (S35).

In addition, the fuel supply control method according to the present invention returns to the step S20 until the ignition is turned off (S50) and performs the fuel supply control, and only the gasoline mode, LPG mode, and automatic mode are shown in FIG. In this case, each mode is a logic driven independently, so that, for example, when the input data is the LPG mode in step S19, the mode may directly enter the LPG mode 30 without going through the gasoline mode S20. Can be.

Therefore, according to the fuel supply control method according to the present invention, when a firmware error occurs in the LPG ECU and malfunctions, it is possible to simply correct the error by connecting an external device to the can communication, if the upgrade is required, LPG ECU itself Easy quality improvement is possible without replacing the

Figure 3 is a flow chart illustrating in detail the LPG fuel supply control method of the fuel supply control method for a gasoline and LPG combined vehicle according to the present invention. As shown in Figure 3, the gasoline fuel supply control according to the present invention of the step (S35) will be described in detail.

First, it starts with checking whether the cooling water temperature is 40 degreeC or more (S35-1).

In this case, the engine starts when the coolant temperature is lower than the appropriate temperature (40 ° C. in this embodiment, which can be changed by region and vehicle type). It is called cold start, and the engine RPM is increased to raise the low temperature quickly. do.

On the contrary, it is called warm-up start that an engine runs with cooling water temperature higher than appropriate temperature, and it does not need to increase engine RPM in this case.

Therefore, different control is required according to the coolant temperature, and when the cold start is applied, the fuel injection amount is controlled by the PWM duty corresponding to the coolant temperature built in the central processing unit (S35-1a).

Here, PWM duty is preset by dividing the coolant temperature by sections, and as the temperature decreases, the duty value increases nonlinearly to quickly control the engine speed.

In addition, in the step (S35-1), if not cold start, control according to the throttle opening amount using the throttle position sensor or control according to the acceleration section and the deceleration section for the warm-up start or control when the engine RPM is the maximum Each control is driven independently.

Therefore, when a condition (event) to control each step occurs, the condition is periodically detected, so that control can be immediately entered.

When the respective controls are sequentially described according to the reference numerals, when the throttle opening amount enters a low section (S35-2), the oxygen sensor receives feedback of the oxygen amount to perform PI (proportional integral) control and is calculated accordingly. The duty (%) is to transmit the PWM duty and control signal to one of the solenoid valves through the LPG controller (S35-2a).

Here, the fuel supply control method of the present invention are all processed by a program embedded in the central processing unit of the LPG ECU, and accordingly, in step S35-2a, only the PWM duty and the control signal are output to the LPG controller.

While the control of the step (S35-2a), if a condition to perform the control of the other step occurs, it may enter another step.

Also, when the throttle opening amount enters the intermediate section (S35-3), similarly to the step S35-2a, the oxygen sensor receives feedback of the oxygen amount to perform PI (proportional integral) control, and the calculated duty ( %) Transmits the PWM duty and control signal to one of the solenoid valves through the LPG controller (S35-3a).

However, the gain in the proportional integral control of the section in which the throttle opening amount is low and the middle section is set differently, and the gain in the low section is preferably smaller than the gain in the middle section.

When the throttle opening amount enters a high section (S35-4), the engine RPM signal is received from the taco signal, and the control signal is controlled by the PWM duty corresponding to the engine RPM among the programs stored in the central processing unit through the LPG controller. By transferring to one of the valves, the fuel injection amount is controlled (S35-4a).

In addition, in the acceleration period (S35-5), the fuel injection amount is controlled by applying a preset PWM duty value (S35-5a), and the fuel injection amount according to the PWM duty value is output for a predetermined time (S35-5). -5b).

Here, in the present invention, the acceleration section means a case where the throttle opening amount enters the middle section from the low section, and further includes the case where the middle section enters the high section, the PWM duty value is preferably set respectively. .

On the contrary, in the case of the deceleration section (S35-6), the fuel injection amount is controlled by applying a preset PWM duty value (S35-6a), and the PWM duty until the current engine RPM drops to the reference engine RPM set in the deceleration section. The fuel injection amount according to the value is output (S35-6b).

In this case, the deceleration section refers to a case in which the throttle opening amount is entered from the middle section to the low section, and further includes the case in which the throttle opening amount is entered from the high section to the middle section.

In addition, the PWM duty of the acceleration section is preferably set higher than the PWM duty of the deceleration section.

In addition, when the engine RPM is at the maximum value (max) (S35-7), the PWM duty is set to 0 to stop the fuel injection (S35-7a), whereby the fuel supply is stopped.

Finally, it is checked whether the gasoline fuel supply control is terminated, i.e., if the input data is changed to the gasoline mode (S35-8), and if it is not the gasoline mode, the fuel supply according to the present invention is the LPG mode or the automatic mode. The control returns to step S35-1 to carry out the control method continuously.

In this case, when the vehicle enters the LPG mode from the automatic mode, the gasoline mode is not changed again. Therefore, even if only the gasoline mode is checked, the end condition may be satisfied.

Since the gasoline fuel supply control of the present invention is provided with various control steps, when the user presses the accelerator pedal, the vehicle can adjust fuel injection amount according to the control step to improve fuel efficiency, and the reaction speed of the vehicle and Increasing sensitivity may increase the quality of emotion that a user feels.

4 is a diagram illustrating a duty calculation method of a fuel supply control method for a combined gasoline and LPG vehicle according to the present invention. As shown in FIG. 4, in the section in which the throttle opening amount is low and the middle section, the duty is calculated using an oxygen sensor.

That is, if the oxygen sensor state is RICH and the previous oxygen sensor state is LEAN, the PWM output duty value is the current PWM output duty value-P (gain) 1.

Also, if the oxygen sensor state is rich and the previous oxygen sensor state is rich, the PWM output duty value becomes the current PWM output duty value -I (gain) 1.

On the other hand, if the oxygen sensor state is thin and the previous oxygen sensor state is rich, the PWM output duty value becomes the current PWM output duty value + P (gain) 2, if the oxygen sensor state is sparse and the previous oxygen sensor state is also sparse. The PWM output duty value becomes the current PWM output duty value + I (gain) 2.

Here, P (gain) is called x (%) and I (gain) is defined as y (% / s).

On the other hand, in the case where the throttle opening amount is high, the duty table according to the engine RPM is called and used, and the PWM output (x) is used.

In addition, in the acceleration section, the PWM output is x, and the deceleration section is the case where the current engine RPM is larger than the fuel cut reference RPM, and the PWM output maintains the value of x as in the acceleration section while the above conditions are maintained.

In the above described exemplary embodiments of the present invention by way of example, the scope of the present invention is not limited only to this specific embodiment, and those skilled in the art within the scope of the claims of the present invention Changes may be made as appropriate.

1 is a block diagram schematically showing the configuration of a fuel supply control apparatus for a gasoline and LPG combined vehicle according to the present invention.

2 is a flow chart schematically showing a fuel supply control method for a gasoline and LPG combined vehicle according to the present invention.

Figure 3 is a flow chart illustrating in detail the LPG fuel supply control method of the fuel supply control method for a gasoline and LPG combined vehicle according to the present invention.

Figure 4 is a view of the duty calculation method of the fuel supply control method for a gasoline and LPG combined vehicle according to the present invention.

<Brief description of reference numerals for the main parts of the drawings>

10: input unit 11: ignition key

13: switch module 13a: input means

13b: display means 15: detection means

15a: coolant sensor 15b: throttle position sensor

15c: oxygen sensor 17: external device

30: LPG ECU 31: Voltage Regulator

32: overvoltage sensor 33: first relay

37: CANBUS TRANSMITTER 34: CENTRAL PROCESSOR

35: gasoline connection controller 35a: second relay

35b: equivalent resistance 35c: third relay

36: LPG controller 36a: solenoid valve

36b: Solenoid Valve Diagnosis 50: Output

51: gasoline fuel gauge 51a: gasoline injector

51b: gasoline pump 53: LPG fuel gauge

53a: solenoid valve 70: vehicle ECU

Claims (14)

An input unit for outputting an input value of vehicle state information data, a vehicle ECU (Engine Control Unit) and LPG ECU that controls the output amount of gasoline and LPG injected into the engine with the state information data by a pre-stored program, the vehicle ECU and LPG In the fuel supply control apparatus for a gasoline and LPG combined vehicle including a gasoline fuel system and LPG fuel system for injecting fuel to the engine by the control of the ECU, The LPG ECU includes a voltage regulator for adjusting a voltage input by an ignition key of the input unit, an overvoltage detector for detecting and removing an overvoltage of a voltage output from the voltage regulator, and an input value for selecting fuel injected into an engine. And a gasoline connection controller and an LPG controller connected to or disconnected from the gasoline fuel gauge and the LPG fuel gauge, a central processing unit having the program embedded therein to control each component, and transmitting data from the outside of the LPG ECU to the central processing unit. Fuel supply control device for a gasoline and LPG combined vehicle comprising a can bus transmitter provided to be able to. The method according to claim 1, The LPG ECU is a first relay driven to output oxygen amount data input from the input unit to the LPG ECU or the vehicle ECU. Fuel supply control device for a gasoline and LPG combined vehicle further comprising a. The method according to claim 1, The gasoline connection controller A second relay for selectively connecting the gasoline injector of the gasoline fuel system and the vehicle ECU; An equivalent resistance to replace the gasoline injector with the same resistance as the gasoline injector if the gasoline injector and the vehicle ECU are not connected by driving of the second relay; A third relay selectively connecting the gasoline pump and the vehicle ECU Fuel supply control device for a gasoline and LPG combined vehicle comprising a. The method according to claim 1, The LPG controller A solenoid valve controller for controlling opening and closing of the solenoid valve with a PWM control signal calculated by a program of the central processing unit; Solenoid valve state diagnosis device for outputting a feedback signal to the central processing unit by detecting the short circuit or opening of the signal line of the solenoid valve Fuel supply control device for a gasoline and LPG combined vehicle comprising a. A first step of resetting a program using can communication, when the data input from the outside of the gasoline and LPG combined vehicle matches the data of the central processing unit of the LPG ECU; A second step of initializing state information of the vehicle and receiving data of a switch module for selecting fuel when mismatching or resetting is completed in the first step; When the data of the switch module is in the gasoline mode, the solenoid valve is closed, and the vehicle ECU, the oxygen sensor and the gasoline fuel gauge are connected to perform fuel supply control using gasoline, When the data of the switch module is the LPG mode, the vehicle ECU, the oxygen sensor, the gasoline fuel gauge is released, the solenoid valve is opened to perform fuel supply control using the LPG, A third step of controlling the gasoline mode until entering the deceleration section when the data of the switch module is in the automatic mode, and performing LPG mode control when entering the deceleration section; Fuel supply control method for a gasoline and LPG combined vehicle comprising a. The method according to claim 5, Fuel supply control using the LPG When the state information of the vehicle enters the preset coolant temperature, the throttle valve opening amount, the acceleration section, the deceleration section, and the engine RPM conditions, the fuel supply of the combined gasoline and LPG vehicle is performed according to the condition information. Control method. The method according to claim 6, And controlling the fuel injection amount with a PWM duty corresponding to the coolant temperature when the coolant temperature is lower than a preset temperature. The method according to claim 6, The throttle valve opening amount is set to a low section when the engine is idle, a middle section when the throttle valve opening amount is partial, and a high section when the throttle valve opening amount is maximum, In the low section and the middle section, the fuel injection amount is controlled by the PWM duty calculated by proportional integral control by receiving the data of the oxygen sensor. The fuel supply control method of the gasoline and LPG combined vehicle, characterized in that for receiving the engine RPM is input via the taco signal in the high section, the fuel injection amount to control the PWM duty corresponding to the preset engine RPM. The method according to claim 8, The proportional integral control gain of the low section is less than the proportional integral control gain of the intermediate section fuel supply control method for a combined gasoline and LPG vehicle. The method according to claim 9, The acceleration section entering the intermediate section from the low section for a predetermined time, the fuel injection amount is controlled by the PWM duty set in the acceleration section, Combination of gasoline and LPG in the deceleration section entering the low section from the intermediate section to control the fuel injection amount with the PMW duty set in the deceleration section until the engine RPM reaches a preset reference engine RPM How to control fuel supply of a vehicle. The method according to claim 10, The PWM duty set in the acceleration section is greater than the PWM duty set in the deceleration section fuel supply control method for a combined gasoline and LPG vehicle. The method according to claim 6, Receiving the engine RPM through the taco signal, when the engine RPM is a preset maximum engine RPM, the fuel supply control method for a gasoline and LPG combined vehicle, characterized in that for setting the PWM duty to 0 to stop fuel supply. The method according to any one of claims 6 to 12, The fuel supply control using the LPG is performed by receiving the state information periodically, and before the fuel supply control using the LPG is performed, the previous control is released. The fuel supply control of the combined gasoline and LPG vehicles is performed. Way. The method according to any one of claims 6 to 12, The fuel supply control method using the LPG is repeatedly performed according to the state information until the data of the switch module is switched to the gasoline mode, the fuel supply control method for a gasoline and LPG combined vehicle.

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