KR101360166B1 - Torque control system and method of diesel engine for commercial vehicle - Google Patents

Abstract

The present invention relates to a torque control system and a control method of a diesel engine for a commercial vehicle. And a torque setting unit for setting the maximum torque of the engine based on the load amount calculated by the load calculating unit, and a controller for generating a torque limit signal to limit the output of the engine based on the torque set by the torque setting unit. The main control unit is configured to limit the maximum torque of the engine by supplying a certain amount of fuel to the engine until the running speed of the vehicle reaches the shift speed when the torque of the engine reaches the maximum torque by the torque limit signal. To prepare.
By using the above-described torque control system and control method for a diesel engine for commercial vehicles, the present invention sets the maximum torque of the engine to a smaller value as the load amount of the vehicle decreases, and when the torque of the engine reaches the set maximum torque, The maximum torque of the engine is limited by supplying a constant amount of fuel to the engine until the traveling speed reaches the speed.

Description

TORQUE CONTROL SYSTEM AND METHOD OF DIESEL ENGINE FOR COMMERCIAL VEHICLE}

The present invention relates to a torque control system and control method for a diesel engine for commercial vehicles, and more particularly, to a torque control system and control method for a diesel engine for commercial vehicles that controls the upper limit of the engine torque based on the load weight of the vehicle.

In general, diesel engines are raised to the maximum torque point with increasing engine speed up to the speed of the vehicle being shifted up in each gear stage for maximum acceleration of the vehicle.

Cargo-carrying vehicles, such as trucks with diesel engines, require a high load of the engine when operating at maximum loading, and thus use a high range of engine torque to accelerate the vehicle or maintain a constant speed at each shift stage.

On the other hand, commercial vehicles to which diesel engines are applied, such as small, medium, large trucks, buses, and special vehicles, can maintain sufficient acceleration and power performance even when using a low range of engine torque in a tolerant state or a low load state.

And unlike a gasoline engine that regulates the output by the amount of inhaled air and the amount of fuel injected, the diesel engine injects fuel according to vehicle information such as the position of the accelerator pedal, speed ratio, vehicle speed, and engine torque in the WOT (Wide Open Throttle) state. The output is controlled by adjusting only the fuel injection amount using the device.

Here, the injection amount of fuel per cylinder is increased in proportion to the size of the engine torque according to the increase in the load amount of the vehicle or the load required when the vehicle is going up the slope.

That is, the conventional freight transport vehicle uses the same torque diagram and shift timing in the maximum load state or the tolerance state, so that when the truck drivers step on the same accelerator pedal to accelerate the vehicle regardless of the load amount, the maximum load state Assuming standard acceleration, rapid acceleration occurs when the load is small or under tolerance.

The conventional freight transport vehicle controls the engine torque by controlling the fuel injection amount in the same manner according to the information detected by the engine control apparatus regardless of the load weight of the vehicle.

As a result, the conventional freight transport vehicle uses the high torque of the engine at the same time as the accelerator pedal is pressed hard when the vehicle is started or the vehicle is driven, depending on the driver's driving pattern, even in a vehicle driving state where the engine requires less load. Cause unnecessary fuel consumption.

As a result, the rapid acceleration of the vehicle in the conventional freight transport vehicle has a problem that also has a bad effect on the endurance life of the rotary drive unit that requires lubrication by increasing the heat load on the powertrain components including the engine.

An example of a technique for solving this problem is described in Korean Patent Registration No. 10-0101614 (October 17, 2003, hereinafter referred to as 'Patent Document 1').

The engine control apparatus and method of the vehicle according to Patent Document 1 detects the vehicle speed and the engine speed when there is an engine output adjustment switch signal, calculates the gear transmission ratio by the detected vehicle speed and the engine speed, and calculates the calculated gear speed ratio. If the engine speed is smaller than the set stage and the engine speed is greater than the set speed and the vehicle speed is less than the set vehicle speed, the fuel injection amount is controlled to be appropriately reduced from the maximum fuel injection amount.

However, Patent Document 1 has a limitation in precisely controlling the engine torque only by controlling the fuel injection amount, as the fuel injection amount is reduced according to the weight information of the vehicle.

In particular, Patent Document 1 has a problem that it is not possible to sufficiently obtain the effect of reducing the fuel consumption by controlling the fuel injection amount only when the gear shift ratio, the engine speed, the vehicle speed satisfies the preset criteria.

Republic of Korea Patent Registration No. 10-0101614 (October 17, 2003 announcement)

The present invention is to solve the above problems, it is an object of the present invention to provide a torque control system and control method for a diesel engine for commercial vehicles that controls the upper limit of the torque of the engine based on the load of the cargo.

Another object of the present invention is to provide a torque control system and control method for a diesel engine for a commercial vehicle, which improves fuel efficiency of a vehicle by reducing fuel consumption when the vehicle is in a tolerant state or when a small amount of cargo is loaded.

According to a feature of the present invention for achieving the object as described above, the present invention is a CAN transceiver for communicating with the main control unit of the vehicle, the load amount for calculating the loading amount of the vehicle using the driving information received through the CAN transceiver A calculation unit, a torque setting unit that sets the maximum torque of the engine based on the load amount calculated by the load calculation unit, and a controller that generates a torque limit signal to limit the output of the engine based on the torque set by the torque setting unit. In addition, when the torque of the engine reaches the maximum torque by the torque limit signal, the main controller supplies a predetermined amount of fuel to the engine until the running speed of the vehicle reaches the shift speed to limit the maximum torque of the engine. .

The present invention further includes a weight sensor installed on the wheel of the vehicle and detecting a load applied to the axle, wherein the load calculator calculates a load of the vehicle by using a detection signal of the weight sensor.

The driving information may include driving speed of the vehicle, rotation speed of the engine, and torque information.

The invention further includes an inclination sensor for detecting the inclination of the road on which the vehicle travels, wherein the control unit determines the inclination of the road using the detection signal of the inclination sensor, and controls to release the maximum torque limit of the engine when climbing uphill Characterized in that.

The invention further comprises setting means for setting the maximum torque limit of the engine on or off.

According to another feature of the invention, the present invention comprises the steps of (a) calculating the load of the cargo loaded on the vehicle, (b) setting the maximum torque of the engine based on the load calculated in the step (a), (c) when the torque of the engine reaches the maximum torque set in step (b), supplying a constant amount of fuel to the engine to maintain the constant torque of the engine, and (d) constantly supplying in step (c) And controlling the vehicle to reach the preset speed by using the fuel.

Step (a) is performed by performing CAN communication with the main control unit of the vehicle to calculate the load information by calculating the driving information of the vehicle, and the driving information includes the driving speed of the vehicle, the engine speed and the torque. It is done.

Step (a) is characterized in that for calculating the load amount of the vehicle by using the detection signal of the weight sensor installed on the wheel of the vehicle.

The present invention further includes the step of (e) determining the inclination of the road on which the vehicle travels by using the detection signal of the inclination sensor, wherein step (c) is characterized in that the maximum torque limit of the engine is released when climbing uphill. .

Step (b) is characterized in that the preset value set in the section corresponding to the load amount calculated from the maximum load of the vehicle divided into a plurality of sections, characterized in that for setting the maximum torque of the engine.

As described above, the present invention sets the maximum torque of the engine to a smaller value as the load of the vehicle is smaller, so that when the engine torque reaches the set maximum torque, a certain amount of fuel until the running speed of the vehicle reaches the shift speed Supply the engine to limit the maximum torque of the engine.

Therefore, the present invention has the effect of improving fuel economy of the vehicle by reducing the amount of fuel supplied to the engine and preventing unnecessary consumption of fuel, compared to the case of controlling the torque of the engine based on the maximum loading state.

In addition, the present invention determines whether the slope is climbing using the detection signal of the inclination sensor, and when climbing the slope, the maximum torque limit function of the engine is released to set the maximum torque of the engine to 100% of the engine output, thereby decelerating the vehicle. You can prevent it.

In addition, the present invention can improve the durability life of the engine by setting the maximum torque of the engine low when the vehicle is in a tolerance state or a small load amount.

In addition, the present invention has the effect of enabling eco-friendly driving (eco driving) by controlling the vehicle to be constantly accelerated irrespective of the load amount of the vehicle.

In addition, the present invention has the effect of extending the maintenance period of the vehicle by suppressing the deterioration of the engine oil by controlling the maximum torque of the engine to prevent the occurrence of rapid acceleration section.

1 is a block diagram of a torque control system of a commercial diesel engine according to a preferred embodiment of the present invention.
FIG. 2 is a graph of a maximum torque of an engine set according to a load amount of a vehicle in the torque control device shown in FIG. 1;
3 is a flowchart illustrating a step-by-step control method of the torque control system of a commercial vehicle diesel engine according to an embodiment of the present invention;
4 is a graph illustrating a maximum torque of an engine set for each vehicle load by a control method of a torque control system of a commercial vehicle diesel engine illustrated in FIG. 3;
FIG. 5 is a graph illustrating shift timing and fuel consumption according to a maximum torque of an engine set for each vehicle load in FIG. 4. FIG.

Hereinafter, a torque control system and a control method of a commercial vehicle diesel engine according to a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.

1 is a block diagram of a torque control system of a commercial diesel engine according to a preferred embodiment of the present invention, Figure 2 is a graph of the maximum torque of the engine set according to the load amount of the vehicle in the torque control device shown in FIG. to be.

Torque control system 10 of a commercial vehicle diesel engine according to an embodiment of the present invention, as shown in Figure 1, the CAN transceiver 11, the CAN transceiver 11 for communicating with the main control unit 20 of the vehicle A load calculation unit 12 for calculating a load amount of the vehicle by using the driving information received through a), a torque setting unit 13 for setting a maximum torque of the engine based on the calculated load amount, and an output of the engine according to the set torque And a control unit 14 for generating a torque limit signal to limit the control signal.

In addition, the torque control system 10 of a commercial vehicle diesel engine according to a preferred embodiment of the present invention further includes setting means 15 for setting the maximum torque control function of the engine on or off.

The main controller 20 is an electronic control unit for controlling the operation of the engine, automatic transmission, anti-lock brake system (ABS), electric brake system (EBS), and the like. The engine is controlled to be driven according to the driving information detected by various sensors such as a torque sensor.

Here, the main controller 20 sets the maximum torque of the engine according to the torque limit signal transmitted from the controller 14 through the CAN transceiver 11 and controls the engine torque to reach the set maximum torque.

To this end, the CAN transceiver 11 is connected to the main control unit 20 via a CAN communication line, receives the driving information from the main control unit 20 and transmits it to the load calculation unit 12, the torque of the control unit 14 The limit signal is transmitted to the main control unit 20.

The load amount calculating unit 12 calculates the load amount of the cargo loaded on the vehicle by calculating the driving information using a preprogrammed control logic.

The torque setting unit 13 includes a memory (not shown) for dividing a load of cargo loaded into a vehicle into a plurality of sections, for example, three sections and storing an upper torque limit for each divided section.

Accordingly, the torque setting unit 13 sets the upper limit of the torque of the corresponding section as the maximum torque of the engine by corresponding the loading amount calculated by the loading calculation unit 12 to the section stored in the memory.

For example, as shown in FIG. 2, the torque setting unit 13 sets the maximum torque of the engine according to the load amount of the vehicle.

That is, the torque setting unit 13 sets the maximum torque of the engine to be close to 100% of the engine output as the loading amount of the vehicle approaches the maximum loading amount, and sets the maximum torque of the engine as the loading amount of the vehicle approaches the tolerance state. It is set to approach a minimum value of the engine power, for example about 30%.

The controller 14 generates a torque limit signal to limit the torque of the engine to the maximum torque set by the torque setting unit 13, and transmits the torque limit signal to the main controller 20 through the CAN transceiver 11.

The setting means 15 is provided with a switch or a button for setting the maximum torque limit function of the engine on or off.

Meanwhile, in the present exemplary embodiment, the loading amount of the vehicle is calculated using the speed, engine speed, and torque of the vehicle through CAN communication with the main controller 20. However, the present invention is not limited thereto.

For example, according to the present invention, as shown in FIG. 1, a weight sensor 16 for detecting a load is installed on a suspension device installed at each wheel of the vehicle, and the weight of the vehicle is detected using a detection signal of the weight sensor 16. It can be changed to yield a payload.

In addition, the present invention is equipped with an inclination sensor 17 for detecting the inclination of the vehicle according to the inclination of the road in case the output shortage of the engine occurs when driving uphill by limiting the maximum torque of the engine in accordance with the load amount.

That is, the present invention releases the maximum torque limit function of the engine on the uphill road by determining the inclination of the road according to the detection signal of the inclination sensor 17.

Accordingly, the present invention controls the output of the engine to the maximum torque of the engine output when climbing the slope, it is possible to prevent the deceleration of the vehicle due to the increase in load.

Next, with reference to Figures 3 to 5 will be described in detail a control method of the torque control system of a commercial vehicle diesel engine according to an embodiment of the present invention.

3 is a flowchart illustrating a step-by-step control method of the torque control system of a commercial vehicle diesel engine according to a preferred embodiment of the present invention, Figure 4 is a control method of the torque control system of a commercial vehicle diesel engine shown in FIG. FIG. 5 is a graph illustrating a maximum torque of an engine set for each vehicle load, and FIG. 5 is a graph illustrating a shift timing and fuel consumption amount according to the maximum torque of the engine set for each vehicle load in FIG. 4.

As shown in FIG. 3, when driving of the vehicle starts (S10), the controller 14 checks whether the setting means 15 is set to an on state to perform the maximum torque limiting function of the engine (S11). .

If the setting means 15 is set to the off state, the control unit 14 proceeds to step S19 to be described below to set the maximum torque of the engine to 100% of the engine output.

On the other hand, when the setting means 15 is set to the ON state, the CAN transceiver 11 communicates with the main controller 20 to display driving information detected by various sensors such as a vehicle speed sensor, an engine speed sensor, and a torque sensor. Receive (S12).

Then, the load amount calculation unit 12 calculates the load amount of the vehicle by calculating the driving information using the control logic programmed in advance (S13).

Accordingly, the torque setting unit 13 sets the preset value set in the section corresponding to the load calculated from the plurality of sections as the maximum torque of the engine.

For example, in the present embodiment, the load of the vehicle is divided into first to third sections set at 0 to 30%, 30 to 60%, and 60 to 100%, and the maximum torque of the engine for each section is set to the engine in the normal state. The first to third set values are set to 60%, 80%, and 100% of the output.

However, the present invention is not necessarily limited thereto, and the loads may be further divided into sections, or the set values for each section may be variously changed according to the performance of the vehicle.

When the load calculated in step S13 corresponds to the first section in which the load is set to 0 to about 30% based on the maximum load amount of the vehicle (S14), the torque setting unit 13 sets the maximum torque of the engine in advance to the first setting. The value is set to about 60% (S15).

When the load calculated in step S13 corresponds to the second section in which the load is set to about 30 to 60% based on the maximum load of the vehicle (S16), the torque setting unit 13 sets the maximum torque of the engine in advance to the second set. The set value is set to 80% (S17).

In addition, when the load calculated in step S13 corresponds to the third section in which the load is set to about 60 to 100% based on the maximum load of the vehicle (S18), the torque setting unit 13 sets the maximum torque of the engine in advance to the third set in advance. The set value is set to 100% (S19).

As such, when the maximum torque of the engine is set in the torque setting unit 13 according to the loading amount, the controller 14 generates a torque limit signal according to the set maximum torque, and transmits the generated torque limit signal to the main controller 20. Control the CAN transceiver to transmit (S20).

Accordingly, the main control unit 20 receives the torque limit signal, and when the torque of the engine reaches the maximum torque of the torque limit signal, as shown in (a) to (c) of FIG. 4, the engine for each load amount of the vehicle By supplying a certain amount of fuel to the control to maintain a constant maximum torque of the engine.

Subsequently, as shown in FIG. 5, when the traveling speed of the vehicle reaches the speed change, the main controller 20 controls the engine to supply a constant amount of fuel equally at each driving stage.

According to the present invention, the smaller the vehicle load is, the lower the maximum torque of the engine is set to a smaller value so that when the engine torque reaches the set maximum torque, the vehicle is supplied with a constant amount of fuel until the running speed reaches the shift speed. Limit the maximum torque.

Therefore, the present invention can improve the fuel efficiency of the vehicle by reducing the amount of fuel supplied to the engine compared to the case of controlling the torque of the engine on the basis of the maximum loading state to prevent unnecessary consumption of fuel.

In addition, the present invention determines whether the ramp is climbing using the detection signal of the inclination sensor, and when climbing the ramp, the maximum torque limit function of the engine is released to set the maximum torque of the engine to 100% of the engine output to decelerate the vehicle. Prevent the phenomenon.

On the other hand, the control unit 14 checks whether the driving of the vehicle is terminated in step S21, and controls to repeat the steps S11 to S21 until the running of the vehicle is finished.

As a result of the inspection in step S21, when the driving of the vehicle is finished, the control unit 14 ends the operation of the torque control system 10 of the diesel engine for commercial vehicles.

Through the process as described above, the present invention can limit the maximum torque of the engine in accordance with the load amount of the vehicle to reduce the amount of fuel supplied to the engine to prevent unnecessary fuel consumption.

Although the present invention has been described in detail with reference to the above embodiments, it is needless to say that the present invention is not limited to the above-described embodiments, and various modifications may be made without departing from the spirit of the present invention.

The present invention is applied to the technical field of improving the fuel efficiency of the vehicle by preventing the consumption of unnecessary fuel in the case of a low tolerance state or loading amount by variably limiting the maximum torque of the diesel engine according to the loading amount of the vehicle carrying the cargo.

10: Torque Control System for Commercial Vehicle Diesel Engines
11: CAN transceiver 12: payload calculator
13: torque setting unit 14: control unit
15: setting means 16: weight sensor
17: inclination sensor 20: main control unit

Claims (10)

CAN transceiver to communicate with the main control of the vehicle,
A load calculation unit configured to calculate a load of the vehicle by using the driving information received through the CAN transceiver;
A torque setting unit that sets the maximum torque of the engine based on the load amount calculated by the load amount calculating unit;
An inclination sensor for detecting the inclination of the road on which the vehicle travels;
And a controller configured to generate a torque limit signal to limit the output of the engine based on the torque set by the torque setting unit.
The torque setting unit sets a preset value to a maximum torque of an engine in a section corresponding to a load calculated from among sections in which the maximum load of the vehicle is divided into a plurality of sections,
When the torque of the engine reaches the maximum torque by the torque limit signal, the main controller supplies a constant amount of fuel to the engine until the running speed of the vehicle reaches the speed change, thereby limiting the maximum torque of the engine,
The control unit determines the inclination of the road by using the detection signal of the inclination sensor, the torque control system of a commercial vehicle diesel engine, characterized in that to control to release the maximum torque limit of the engine when climbing uphill. The method of claim 1,
Further comprising a weight sensor installed on the wheel of the vehicle for detecting the load applied to the axle,
The load amount calculating unit calculates a load amount of a vehicle by using the detection signal of the weight sensor. The method of claim 1, wherein the driving information
Torque control system of a diesel engine for a commercial vehicle, characterized in that it comprises the driving speed of the vehicle, the rotational speed and torque information of the engine. delete The method of claim 1,
Torque control system for a diesel engine for a commercial vehicle, characterized in that it further comprises setting means for setting the maximum torque limit of the engine on or off. (a) calculating the load of cargo loaded on the vehicle,
(b) setting the maximum torque of the engine based on the load calculated in step (a),
(c) when the torque of the engine reaches the maximum torque set in the step (b), supplying a constant amount of fuel to the engine to maintain the constant torque of the engine,
(d) accelerating the vehicle by using the fuel constantly supplied in the step (c) and controlling the vehicle to reach a preset speed change; and
(e) determining the inclination of the road on which the vehicle travels using the detection signal of the inclination sensor,
In the step (b), a preset value set in a section corresponding to a load calculated from among sections in which the maximum load of the vehicle is divided into a plurality of sections is set as the maximum torque of the engine.
Step (c) is a torque control method of a diesel engine for commercial vehicles, characterized in that to release the maximum torque limit of the engine when climbing uphill. The method according to claim 6,
Step (a) is to perform a CAN communication with the main control unit of the vehicle to calculate the load information by calculating the driving information of the vehicle received,
The driving information is a torque control method of a diesel engine for a commercial vehicle, characterized in that it comprises the running speed of the vehicle, the engine speed and torque. The method according to claim 6,
The step (a) is a torque control method for a diesel engine for a commercial vehicle, characterized in that for calculating the load of the vehicle using the detection signal of the weight sensor installed on the wheel of the vehicle. delete delete

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