KR20160016230A - Diesel particulate filter regeneration system - Google Patents

Abstract

The present invention relates to a diesel particulate matter reduction apparatus regeneration system, including: a throttle valve installed at an air intake of an engine; a particulate matter reduction apparatus for collecting particulate matter (PM) by being installed in an exhaust manifold of the engine; and a control part which decreases intake air quantity of the engine by controlling the throttle valve in order to increase the temperature of an exhaust gas discharged from the engine when entering a regeneration mode as to the particulate matter reduction apparatus.

Description

[0001] Diesel particulate filter regeneration system [0002]

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a system for regenerating a soot reduction apparatus, and more particularly, to a system for regenerating a soot reduction apparatus capable of generating a high temperature exhaust gas at a constant heating value through a throttle valve mounted in an engine,

In recent years, exhaust emissions have been strengthened to prevent environmental pollution caused by automobile emissions worldwide, and researches on diesel engines that are more fuel efficient than those of gasoline engines have been actively conducted in various countries.

In general, although diesel engines have advantages such as excellent fuel efficiency and power output compared to gasoline engines, they have a characteristic that nitrogen oxides (NOx), which is one kind of harmful substances after combustion, are discharged. Accordingly, in the diesel engine, exhaust gas recirculation (EGR) is performed to supply the unburned exhaust gas, which is included in the exhaust gas discharged through the post-combustion exhaust system, to the intake system to be re- Is adopted.

However, the exhaust gas recirculation system is effective in reducing the content of nitrogen oxide, which is one kind of harmful substance in the exhaust gas after combustion, but it is also effective in reducing the amount of particulate matter (soot, particulate material, PM) There is a blind spot that causes a large amount of other pollutants to be discharged.

This phenomenon is inevitably involved in the process of re-burning the unburned exhaust gas. As a result, much efforts are now being made to reduce harmful pollutants such as particulate matter (soot).

Recently, it has been reported that the particulate matter (soot) acts as a most important cause for polluting the atmosphere and also has a great adverse effect on the human body. In recent years, a technique which is popular for reducing particulate matter (soot) One of them is the Diesel Particulate Material Filtering System (DPF) for diesel engines.

That is, the particulate matter removal system for a diesel engine is attached to an exhaust pipe connected to a diesel engine exhaust port used in a vehicle, a construction machine, etc., and collects particulate matter (soot) discharged after combustion through a filter provided in the exhaust system And a particulate matter (soot), which is a contaminant contained in the exhaust gas discharged after the combustion, in the exhaust system in the system, by burning the captured particulate matter by using the temperature of the exhaust gas after combustion, As a result of the research.

However, in the conventional particulate matter removal system for a diesel engine, the particulate matter collected in the filter provided in the exhaust system is combusted by the temperature of the exhaust gas discharged after the combustion. However, the diesel engine, There is a disadvantage that it is difficult to burn the particulate matter (soot) trapped in the filter since the temperature is approximately 200 to 300 DEG C which is much lower than 600 to 700 DEG C necessary for burning the particulate matter.

As a result, many researches have been conducted to raise the temperature of the exhaust gas discharged from the diesel engine after combustion. As a result of this research, it has been studied that the fuel injection after the main injection of fuel in the common rail engine (post injection).

Regeneration using fuel back injection requires the addition of two additional fuels in addition to fuel injection for the engine running condition of the vehicle. The first is to provide a higher amount of heat to the exhaust gas through the combustion, so that the higher temperature is raised, which is insufficient to burn the soot captured on the filter, so that the second additional fuel is injected, The exhaust gas temperature is raised through an exothermic reaction with a DOC (Diesel Oxidation Catalyst) attached to the front of the soot reduction apparatus in order to remove the exhaust gas carbon monoxide (CO) and hydrocarbon (HC) The exhaust gas is increased to 600 ° C or higher by the injection, and the soot is removed.

Such a regeneration system using the fuel post-injection causes excessive fuel consumption in the regeneration mode and dilutes the fuel in the engine oil. Therefore, there is a problem that the fuel consumption deterioration and the engine oil replacement cycle are shortened.

As a related art, there is disclosed a method of regenerating a particulate matter removal filter of a diesel engine, which is disclosed in Japanese Patent Application Laid-Open No. 10-0514862 (filed on Sep. 07, 2005) and Japanese Patent Application Laid-Open No. 2011-256846 (Entitled " Exhaust gas purifying system, public date: December 22, 2011).

SUMMARY OF THE INVENTION It is an object of the present invention to provide a soot reduction apparatus regeneration system capable of burning soot by generating a high temperature exhaust gas with a constant heating value through a throttle valve mounted on an engine .

BRIEF DESCRIPTION OF THE DRAWINGS Other objects and advantages of the invention will become more apparent from the following detailed description of preferred embodiments with reference to the attached drawings, in which:

A soot reduction system recycling system according to the present invention includes: a throttle valve mounted on an intake port of an engine; A soot reduction device mounted on an exhaust manifold of the engine to collect particulate matter (PM); And a controller for controlling the throttle valve to increase the temperature of the exhaust gas discharged from the engine when the regeneration mode is entered into the diesel particulate filter.

In the system for regenerating the soot reduction apparatus according to the present invention, it is preferable that the system further comprises a temperature sensor for measuring the temperature of the soot reduction apparatus, wherein the control unit controls the throttle Control the valve.

In the soot reduction system recycling system according to the present invention, the control section performs a first regeneration step of controlling the throttle valve so that the temperature of the soot reduction apparatus is raised to a preset regeneration target temperature.

The control unit performs a second regeneration step of controlling the throttle valve so that the temperature of the diesel particulate filter device is maintained at the regeneration target temperature after the first regeneration step .

In the system for regenerating a soot reduction apparatus according to the present invention, the first regeneration step ends when a preset time has elapsed and the regeneration target temperature is reached.

In the system for regenerating the soot reduction apparatus according to the present invention, the second regeneration step is terminated when a predetermined time has elapsed or when the soot collection amount of the soot reduction apparatus has become a predetermined amount or less.

In the system for regenerating the soot reduction apparatus according to the present invention, it is preferable that the regeneration mode for the soot reduction apparatus further comprises a pressure sensor for measuring the pressure before and after the soot reduction apparatus, And enters when the pressure difference before / after the reduction device is equal to or greater than a preset differential pressure.

The present invention generates a high-temperature exhaust gas by injecting a constant amount of heat with a small intake amount through a throttle valve mounted on an engine, and burns and removes soot.

Further, thermal stress that can be received when the exhaust gas is heated slowly to rapidly reduce the possibility of breakage of the soot reduction apparatus.

In addition, since the intake amount of the throttle valve can be controlled, fuel consumption is reduced to eliminate fuel consumption deterioration, and the engine oil change period is increased.

1 is a block diagram of an embodiment of a soot reduction apparatus regeneration system according to the present invention;
2 is a graph showing a regenerative waveform of the soot reduction apparatus regeneration system according to the present invention,
3 is a flowchart of an embodiment of a method for regenerating a soot reduction apparatus according to the present invention,
4 is a flowchart of an embodiment of a method for regenerating a soot reduction apparatus according to the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a preferred embodiment of a system for regenerating a soot reduction apparatus according to the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a block diagram of an embodiment of a soot reduction apparatus reproducing system according to the present invention, and FIG. 2 is a graph showing a reproducing waveform of the soot reduction apparatus reproducing system according to the present invention.

1 and 2, the system 100 for regenerating a soot reduction apparatus according to the present invention includes a throttle valve 110, a soot reduction apparatus 120, and a control unit 130.

The throttle valve 110 is mounted to the intake port of the engine. An engine is a diesel engine used in a vehicle, a construction machine, a ship, and the like.

The throttle valve 110 is a valve for opening and closing a duct to adjust the amount of air sucked into the engine by rotating the disk. The throttle valve 110 adjusts the amount of intake air by adjusting the time of the injector change in the control unit 130, which will be described below.

The throttle valve 110 may be placed in a common rail direct engine (CRDI) engine, a type of diesel engine, which is used not only to reduce the smoke but also to regulate the output.

Since the amount of fuel to be injected is constant, the calorific value of the fuel supplied through the combustion reaction is fixed. The calorific value is injected through the throttle valve 110 through the throttle valve 110 to reduce the exhaust gas to a higher temperature And the burned soot is removed by using the raised exhaust gas.

A diesel particulate filter (DPF) 120 is mounted on the exhaust manifold of the engine to collect particulate matter (PM). The exhaust manifold to which the particulate emission control device 120 is mounted is a component connected to the exhaust port of the engine and collects exhausted combustion gases and discharges the exhausted gas through the exhaust pipe. It is important that the soot reducing apparatus 120 measures the amount of the collected soot and regenerates it at an appropriate time.

The soot reducing apparatus 120 physically collects soot by using a honeycomb catalyst filter made of porous ceramics. The collected soot is regenerated when certain conditions are satisfied, and regeneration means the process of burning and removing the collected soot.

When the soot is excessively collected in the exhaust manifold, the soot reduction apparatus 120 performs maintenance by repeatedly performing regeneration, which is a process of raising the temperature of the exhaust gas and burning the soot into a gas (gas) state. The soot reduction apparatus 120 burns and removes the soot collected in the exhaust manifold to smoothly collect new soot.

The control unit 130 controls the throttle valve 110 to increase the temperature of the exhaust gas discharged from the engine at the time of entering the regeneration mode for the flue gas desulfurizer 120 to reduce the intake amount of the engine. Generally, an electronic control unit (ECU) is a type of the control unit 130.

The control unit 130 controls the opening and closing operations of the throttle valve 110 based on the temperature of the exhaust gas reducing apparatus 120 measured by the temperature sensor 140 described below to adjust the intake air amount of the engine.

The control unit 130 performs a first regeneration step of controlling the throttle valve 110 so that the temperature of the diesel particulate filter 120 is raised to a preset regeneration target temperature. The reason for adopting the first regeneration step is to minimize the possibility of breakage of the soot reduction apparatus 120 by reducing thermal stress generated when the exhaust gas is rapidly heated. When the regeneration mode of the diesel particulate filter 120 is started, the regeneration mode is slowly heated to the regeneration target temperature for 5 minutes or more.

The predetermined regeneration target temperature of the diesel particulate filter 120 is 600 to 700 占 폚, preferably 650 占 폚. If the regeneration target temperature is lower than 650 ° C, soot in the exhaust gas reduction apparatus 120 is not oxidized and oxidized and hardly changes into a gas state. Even if it changes to a gas state, the reaction speed is very slow It takes a lot of time to remove the soot.

In other words, at the high temperature at which the regeneration target temperature reaches 650 DEG C, the catalyst is further activated so that the soot is oxidized to ash. The catalyst is a substance that helps the reaction of the substance to be reacted easily without changing itself. Three kinds of precious metals such as platinum (Pt), palladium (Pd) and rhodium (Rh) are used as catalysts for automobiles.

The first regeneration step ends when a preset time has elapsed and the regeneration target temperature has been reached. Specifically, in the first regeneration step, the regeneration target temperature of 650 ° C is maintained, and the regeneration is terminated according to the elapse of the regeneration time of 10 minutes to enter the second regeneration step.

The control unit 130 performs a second regeneration step of controlling the throttle valve 110 so that the temperature of the diesel particulate filter 120 is maintained at the regeneration target temperature after the first regeneration step. The second regeneration step that has entered from the first regeneration step regenerates the soot collected in the exhaust manifold in a gas (gas) state. Whether or not the second regeneration step is entered depends on the continuation of the regeneration target temperature and the regeneration progress time.

The second regeneration step is terminated when a predetermined time has elapsed or when the amount of soot collected by the particulate removing apparatus 120 has become a predetermined amount or less. Specifically, the second regeneration step is terminated when the regeneration target temperature of 650 ° C reached the regeneration time of 15 minutes or more or the amount of soot collection is 2 g or less.

In the second reproduction step, when the second reproduction step ends, the reproduction time is set to the initialization and is used as the reproduction start time in the reproduction mode in the next first reproduction step. This is to provide start of playback at the same playback time '0' time.

The control unit 130 controls the injection target fuel injection amount, the injection timing, and the intake air amount after determining the temperature value measured from the temperature sensor 140 at the entrance of the soot reduction apparatus 120 to the regeneration target temperature. The control unit 130 determines the collection and reproduction process, and the entire process is automatically performed.

The temperature sensor 140 measures the temperature of the soot reduction apparatus 120. The temperature sensor 140 is mounted before / after the diesel particulate filter 120, and is preferably mounted at the inlet of the diesel particulate filter 120 to measure the temperature before and after passing through the diesel particulate filter 120. The control unit 130 controls the engine and the related device through the pre- / post-measurement temperature to remove the collected soot.

The temperature sensor 140 is mainly used for measuring the engine temperature, the air temperature, the fuel temperature, and the like. Inside the temperature sensor 140, an NTC-semiconductor resistance is provided, and the resistance value of the NTC-resistance is lowered as the temperature rises.

The temperature sensor 140 changes the electrical resistance according to the temperature of the inlet of the soot reduction apparatus 120, and the control unit 130 controls the indicator light or the movement of the needle.

The pressure sensor 150 measures the pressure before / after the diesel particulate filter 120. The pressure sensor 150 is mounted before or after the diesel particulate filter 120 and is mounted to the inlet of the diesel particulate filter 120 such as the temperature sensor 140 to measure the pressure before and after passing through the diesel particulate filter 120 . Using the pre- and post-pressures measured, the controller 130 controls the engine and related devices to remove the collected soot.

The regeneration mode for the particulate reduction apparatus 120 is entered when the pressure difference before / after the particulate reduction apparatus 120 measured by the pressure sensor 150 is equal to or higher than a predetermined differential pressure. The control unit 130 for controlling the state of the engine or the electronic control unit (ECU), which is a kind of the control unit 130, enters the regeneration mode.

The pressure sensor 150 will eventually fail if it is not continuously subjected to regeneration due to the criterion of regeneration time along with the mileage and simulation. The regeneration is also expressed differently, so that the soot abatement device performs the self-cleaning function.

The pressure sensor 150 is the most used condition, and the amount of soot collected is checked before and after the soot reduction apparatus. As the soot is collected in the catalyst, the air flow is blocked and the pressure difference becomes larger as the soot is collected in the catalyst.

2 is a graph showing the regenerative waveform of the soot reduction apparatus regeneration system according to the present invention.

As shown in FIG. 2, in the graph showing the reproduction waveform, the X-axis represents the reproduction time and the Y-axis represents the reproduction temperature.

The temperature rises to the regeneration target temperature in the upward direction at the starting point '0' time, preferably for 5 minutes or more during the time of 't1'. The regeneration target temperature which rises from the starting point '0' time to 't1' time is elevated to 600 to 700 ° C., preferably 650 ° C., to the right with reference to the drawing, . Thereafter, the temperature elevated during the regeneration time of 't1' is maintained for the time of 't2', about 10 minutes.

The time 't2' from the starting point '0' to 't1' is a step for burning the soot into the first regeneration step. The regeneration time of the first regeneration step is maintained at the same regeneration temperature for a period of from t2 to t3 for about 15 minutes.

The time from 't2' to 't3' is the second regeneration stage where the soot is burned and removed. 't3' to 't4' is the ending stage of the second regeneration step, and the regeneration temperature is inclined downward in the right direction with respect to the drawing.

3 is a flowchart of an embodiment of a method for regenerating a soot reduction apparatus according to the present invention.

A method (S100) for regenerating a soot reduction apparatus according to an embodiment of the present invention includes a step S110 of mounting a throttle valve 110 to an intake port of an engine, a step S110 of mounting the exhaust purification apparatus 120 on an exhaust manifold of the engine (S120) of collecting the particulate matter (PM) and the throttle valve 110 to raise the temperature of the exhaust gas discharged from the engine when the control unit 130 enters the regeneration mode for the particulate matter reduction apparatus 120 And reducing the intake air amount of the engine (S130).

The method for regenerating the soot reduction apparatus S100 according to an embodiment of the present invention may further include a step S140 for measuring the temperature of the soot reduction apparatus 120 in the temperature sensor 140, (S150) for measuring the pressure before and after the reduction device 120, respectively.

4 is a flowchart of an embodiment of a method for regenerating a soot reduction apparatus S100 according to the present invention.

As shown in FIG. 4, the method for regenerating the soot reducing apparatus starts with the regeneration of the soot collected in the soot reducing apparatus 120 (S5), and then, through the throttle valve 110, The exhaust gas is increased (S10). Then, it is confirmed whether the preset regeneration target temperature has been reached (S15). If the preset regeneration target temperature is not reached, the exhaust gas is raised through the opening of the throttle valve 110 (S10). Then, the reached regeneration target temperature is maintained until the predetermined regeneration time (S20), and the soot collected in the soot reduction apparatus 120 is removed by regeneration (S25). (S30). If the amount of collected soot is less than a predetermined amount, the regeneration time is increased (S25). Finally, the regeneration of the diesel particulate filter 120 is terminated (S35).

One embodiment of the present invention described above and shown in the drawings should not be construed as limiting the technical idea of the present invention. The scope of protection of the present invention is limited only by the matters described in the claims, and those skilled in the art will be able to modify the technical idea of the present invention in various forms. Accordingly, such improvements and modifications will fall within the scope of the present invention as long as they are obvious to those skilled in the art.

100: Smoke reduction device regeneration system 110: Throttle valve
120: Smoke reduction device 130:
140: Temperature sensor 150: Pressure sensor

Claims (7)

A throttle valve mounted on an intake port of the engine;
A soot reducing device mounted on an exhaust manifold of the engine to collect soot;
And a controller for controlling the throttle valve to decrease the intake air amount of the engine to raise the temperature of the exhaust gas discharged from the engine upon entering the regeneration mode for the exhaust gas recirculation device.
The method according to claim 1,
Further comprising a temperature sensor for measuring the temperature of the diesel particulate filter,
Wherein the control unit controls the throttle valve based on the temperature of the particulate reduction device measured by the temperature sensor.
3. The method of claim 2,
Wherein,
And the throttle valve control means controls the throttle valve so that the temperature of the diesel particulate filter is raised to a preset regeneration target temperature.
The method of claim 3,
Wherein,
And a second regeneration step of controlling the throttle valve so that the temperature of the diesel particulate filter is maintained at the regeneration target temperature after the first regeneration step.
5. The method of claim 4,
Wherein the first reproducing step comprises:
Wherein the predetermined period of time elapses when a predetermined time has elapsed and the regeneration target temperature has been reached.
5. The method of claim 4,
The second reproduction step may include:
And when the predetermined time has elapsed or when the amount of soot collected by the diesel particulate filter has become equal to or less than a preset amount, the regeneration system of the diesel particulate filter.
The method according to claim 1,
Further comprising a pressure sensor for measuring the pressure before and after the smoke elimination apparatus,
Wherein the regeneration mode for the diesel particulate filter is entered when the pressure difference before / after the diesel particulate filter measured by the pressure sensor is equal to or greater than a preset differential pressure.

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