DE102008046745A1 - Turbo-loaded diesel internal-combustion engine system, has control module selectively activating selected zones to release regeneration parts provided downstream to zones of particle material filter and deactivating non-selected zones - Google Patents

Abstract

The system (10) has an electrically heated particle material (PM) filter (34) comprising an upstream end for accommodating exhaust gas. A heating device (35) is divided into a number of zones and spaced at a distance from the end, where the zones comprise a number of sub-zones. The zones and the sub-zones are arranged in layers. A control module (44) selectively activates selected zones to release regeneration parts provided downstream to the zones of the filter and deactivates non-selected zones. One of the zones is arranged in one of the layers, and overlaps with the other zone. An independent claim is also included for a method for operating a turbo-loaded diesel internal-combustion engine system.

Description

statement of government rights

These Revelation was made in accordance with U.S. Government mandate No. DE-FC-04-03 AL67635 developed with the Department of Energy (DoE). The U.S. Government has certain rights to this disclosure.

area

The The present disclosure relates to particulate matter (PM) filters and in particular electrically heated PM filters.

background

The Information in this section is only background information in terms of of the present disclosure and may not provide the Prior art.

Internal combustion engines Like diesel engines, particulate matter (PM) generates by a PM filter is filtered out of exhaust gas. The PM filter is in an exhaust system of Internal combustion engine arranged. The PM filter lowers the emission of PM that while Combustion is generated.

in the Over time, the PM filter becomes full. While regeneration can do that PM are burned in the PM filter. The regeneration can do that He warms of the PM filter to a combustion temperature of the PM. There are different possibilities of performing including regeneration Modifying engine control, using a fuel burner, Using a catalytic oxidizer to lift the Exhaust gas temperature after injection of fuel, using Resistance heating coils and / or using microwave energy. The Resistance heating coils are typically in contact with the PM filter arranged to be heated by both conduction and convection to enable.

Diesel PM burns when temperatures over a combustion temperature, for example 600 ° C, can be achieved. The start the combustion causes a further increase in temperature. While spark-ignited internal combustion engines typically have low oxygen levels in the exhaust stream, Diesel engines have significantly higher oxygen levels. While the increased oxygen levels They can make fast regeneration of the PM filter possible also pose some problems.

PM reduction systems, use the fuel, maintain the fuel economy to reduce. Many fuel-based PM reduction systems For example, reduce fuel economy by 5%. electrical heated PM reduction systems reduce fuel economy a negligible Amount. A longevity of electrically heated PM reduction systems but it is difficult to realize.

Summary

One System includes a particulate matter (PM) filter, which is an upstream end for receiving exhaust gas and a downstream end. A zoned heater is spaced from the upstream one Arranged end and includes N zones, where N is an integer greater than or equal to one, each of the N zones comprising M subzones, where M is an integer greater than one is and where are the N zones and the M subzones in P layers where P is an integer greater than one. A control module selectively activates at least one selected one of the N zones for regeneration in from one of the N zones downstream parts of the Trigger PM filters, and disables non-selected ones N zones.

One Method includes providing a particulate matter (PM) filter, the one upstream Includes end for receiving exhaust gas and a downstream end, spacing the placement of a zoned heater from the upstream end comprising N zones, where N is an integer greater than one, each of the N zones comprising M subzones, and wherein M is an integer greater than or equal to one, and where the N zones and the M subzones are arranged in P layers, where P is an integer greater than one is, and selectively activating at least one selected one of N zones to a regeneration in from the one of the N zones downstream Triggering of the PM filter, and disables non-selected ones N zones.

Further Areas of applicability will be understood from the description provided herein out. It is understood that the description and specifi c Examples are for the purpose of illustration only and not to limit the scope of the present disclosure.

drawings

The Drawings described herein are for the purpose of Illustrative and not intended to be within the scope of the present disclosure restrict in any way.

1 FIG. 10 is a functional block diagram of an exemplary internal combustion engine that includes a particulate matter (PM) filter with a zoned inlet heater that is spaced from the PM filter; FIG.

2 11 shows an exemplary zoning of the zoned inlet heater of the electrically heated particulate matter (PM) filter of FIG 1 closer;

3 FIG. 12 shows an exemplary zoning of the zoned inlet heater of the electrically heated PM filter of FIG 1 closer;

4 FIG. 10 shows an exemplary resistance heater in one of the zones of the zoned inlet heater of FIG 3 ;

5 shows the electrically heated PM filter having a zoned electrical heater spaced from the PM filter;

6 shows heating in the zoned electric heater;

7 FIG. 10 is a flowchart showing steps performed by the control module for regenerating the PM filter; FIG.

8A shows an exemplary overlapping zoning of a multi-layered zoned inlet heater;

8B FIG. 15 shows a cross-section of an exemplary overlapping zoning of the zoned inlet heater of FIG 8A ;

9A shows an exemplary overlapping zoning of a zoned inlet heater having three layers; and

9B FIG. 15 shows a cross-section of an exemplary overlapping zoning of the zoned inlet heater of FIG 9A ,

Detailed description

The The following description is merely exemplary in nature and not intended to facilitate the present disclosure, application or application uses to restrict. It is understood that throughout the drawings appropriate Reference characters designate like or corresponding parts and features.

As As used herein, the term module refers to an application-specific one integrated circuit (ASIC, short of English Application Specific Integrated Circuit), an electronic circuit, a processor (common used, dedicated or group) and a memory, the one or run multiple software or firmware programs, a combinatorial Logic circuit and / or other suitable components, which the described functionality provide.

The The present disclosure utilizes a zone heater. The electric heater is spaced from the PM filter. Different expressed the electric heater is placed in front of the PM filter, but is not in contact with the downstream PM filter. The heater selectively heats parts of the PM filter. The PM filter can be placed close enough to the front of the PM filter, to control the heating pattern. The length of the heater is determined so that the exhaust gas temperature is optimized.

Thermal energy is transferred by the exhaust gas from the heater to the PM filter. Therefore, the PM filter is primarily heated by convection. The electric heater is divided into zones to the for Heating the PM filter required to reduce electrical power. The zones also heat selected ones downstream located parts in the PM filter. By heating only the selected parts the filter becomes the order of magnitude the forces reduced in the substrate due to thermal expansion. Thereby can higher localized soot temperatures while Regeneration can be used without damaging the PM filter.

Of the PM filter is made by selectively heating one or more of the Zones in front of the PM filter and by igniting the soot with the aid of the heated exhaust gas regenerated. When a sufficient front side temperature is reached is off, the heater is turned off and the burning soot wanders cascading the length down the PM filter channel, which is a burning fuse resembles a firecracker. Different said the heater needs to be activated only long enough to the soot ignition too start, and then shut down. Other regeneration systems typically use both conduction and convection and keep the power to the heater (at lower temperatures such as 600 ° C) during the entire soot combustion process. As a result, these systems consume more power than that proposed system in the present disclosure.

The burning soot is the fuel that continues the regeneration. This process continues for each heating zone until the PM filter is completely re is generated.

The Heater zones are spaced so that thermal stress between active heaters is reduced. Therefore, the total stress forces are due smaller by heating and are over distributes the volume of the entire electrically heated PM filter. This procedure allows Regeneration in larger segments of the electrically heated PM filter without generating thermal stress, which damage the electrically heated PM filter.

One largest temperature gradient occurs at the edges of the heaters. Therefore, that allows Activate a heater behind the localized voltage zone another heater has an active heated regeneration volume without Increase in total tension. This maintains the possibility of regeneration improve in a driving cycle and reduces costs and complexity since that System does not have to regenerate as many zones independently.

Referring now to 1 is an exemplary diesel engine system 10 shown schematically in accordance with the present disclosure. It is understood that the diesel engine system 10 is merely exemplary in nature and that the zone-heated particulate filter regeneration system described herein can be implemented in various engine systems that use a particulate filter. Such internal combustion engine systems may include, but are not limited to, gasoline direct injection engine systems and homogeneous compression ignition engine systems. For ease of explanation, the disclosure will be explained in the context of a diesel engine system.

A turbocharged diesel engine system 10 includes an internal combustion engine 12 which burns an air and fuel mixture to produce drive torque. The air enters by passing through an air filter 14 into the system. Air penetrates through the air filter 14 and gets into a turbocharger 18 sucked. The turbocharger 18 compacts them into the system 10 incoming fresh air. The greater the compression of the air in general, the greater the output of the engine 12 , The compressed air then passes through an air cooler 20 before putting in an intake manifold 22 entry.

The air in the intake manifold 22 is in cylinders 26 distributed. Although four cylinders 26 3, the systems and methods of the present disclosure may be embodied in multiple cylinder engines including, but not limited to, 2, 3, 4, 5, 6, 8, 10 and 12 cylinders. It should also be understood that the systems and methods of the present disclosure may be embodied in a V-cylinder configuration. Fuel gets through fuel injectors 28 in the cylinders 26 injected. Heat from the compressed air ignites the air / fuel mixture. Combustion of the air / fuel mixture produces exhaust. The exhaust gas exits the cylinders 26 into the exhaust system.

The exhaust system includes an exhaust manifold 30 , a Diesel Oxidation Catalyst (DOC) 32 and a particulate filter (PM filter) arrangement 34 with a zoned inlet heater (HTR) 35 , Optionally, an EGR valve (not shown) returns some of the exhaust gas to the intake manifold 22 back. The rest of the exhaust gas gets into the turbocharger 18 passed to power a turbine. The turbine facilitates the compression of the air filter 14 absorbed fresh air. The exhaust gas flows out of the turbocharger 18 through the DOC 32 , through the zoned heater 35 and in the PM filter assembly 34 , The DOC 32 oxidizes the exhaust gas based on the air / fuel ratio after combustion. The extent of oxidation increases the temperature of the exhaust gas. The PM filter assembly 34 receives exhaust from the DOC 32 and filters out any particulate matter present in the exhaust gas. The zoned inlet heater 35 is from the PM filter assembly 34 spaces and heats the exhaust gas to a regeneration temperature, as described later.

A control module 44 controls the engine and PM filter regeneration based on various acquired information. More specifically, the control module estimates 44 the loading of the PM filter assembly 34 , When the estimated load reaches a predetermined value and the exhaust gas flow is within a desired range, it is supplied via a power source 46 electrical current to the PM filter assembly 34 to initiate the regeneration process. The duration of the regeneration process may be based on the estimated amount of particulate matter in the PM filter assembly 34 to be changed.

Electric power is generated during the regeneration process at the zoned heater 35 created. More specifically, the energy heats selected zones of the heater 35 the PM filter assembly 34 each over predetermined periods of time. By the heater 35 passing exhaust gas is heated by the activated zones. The heated exhaust gas flows to the downstream filter of the PM filter assembly 34 and heats the filter by convection. The rest of the regeneration process is under Ver the heat generated by the heated exhaust gas passing through the PM filter is realized.

Referring now to 2 FIG. 10 is an exemplary zoned inlet heater. FIG 35 for the PM filter assembly 34 shown closer. The zoned inlet heater 35 is spaced from the PM filter assembly 34 arranged. The PM filter assembly 34 includes a plurality of spaced heater zones including zone 1 (with sub-zones 1A, 1B and 1C), zone 2 (with sub-zones 2A, 2B and 2C) and zone 3 (with sub-zones 3A, 3B and 3C). Zones 1, 2 and 3 may be activated during different respective periods of time.

As exhaust flows through the activated zones of the heater, regeneration occurs in the corresponding portions of the PM filter that first received the heated exhaust gas (eg, areas downstream of the activated zones) or in downstream areas that pass through it ignited cascading burning soot be ignited. The corresponding parts of the PM filter that are not downstream of an activated zone serve as voltage reduction zones. In 2 For example, sub-zones 1A, 1B and 1C are activated, and sub-zones 2A, 2B, 2C, 3A, 3B and 3C serve as voltage-reduction zones.

During the Heating and cooling stretch the corresponding parts of the PM filter downstream of the active heater sub-zones 1A, 1B and 1C thermally and contract thermally. The stress relief subzones 2A and 3A, 2B and 3B, and 2C and 3C reduce one by the expansion and contraction of the heater sub-zones 1A, 1B and 1C caused mechanical stress. After Zone 1 stops the regeneration Zone 2 can be activated and zones 1 and 3 are used as stress reduction zones. After zone 2 regeneration has finished, zone 3 can be activated and zones 1 and 2 serve as voltage reduction zones.

Referring now to 3 Another example arrangement of a zoned inlet heater is shown. A central part may be surrounded by a central part comprising a first circumferential band of zones. The middle part may be surrounded by an outer part comprising a second circumferential band of zones.

In In this example, the central part comprises Zone 1. The first orbiting Band of Zones includes Zones 2 and 3. The second encircling band Zones include Zones 1, 4, and 5. As with the one described above Embodiment will be downstream regenerated parts from active zones while downstream from Inactive zones befindle parts provide a reduction in voltage. As can be seen, in each case one of the zones 1, 2, 3, 4 and 5 be activated. The other zones remain disabled.

Referring now to 4 will be an exemplary resistance heater 100 shown leading to one of the zones (eg zone 3) from the first circulating band of zones in 3 is arranged adjacent. The resistance heater 100 may include one or more coils covering the respective zone to provide sufficient heating.

Referring now to 5 becomes the PM filter arrangement 34 shown closer. The PM filter assembly 34 includes a housing 200. , a filter 202 and the zoned heater 35 , The heater 35 can be between a laminar flow element 210 and a substrate of the filter 202 be arranged. An electrical connector 211 may be the zones of the PM filter assembly 34 provide electrical power as described above.

As can be understood, the heater can 35 from the filter 202 be spaced so that the heating is primarily convection heating. Between the heater 35 and the housing 200. can be an insulation 212 be arranged. From an upstream inlet 214 Exhaust gas enters the PM filter assembly 34 and is through one or more zones of the PM filter assembly 34 heated. The heated exhaust gas travels a distance and is removed from the filter 202 added. The heater 35 can from the filter 202 be spaced and not in contact with it.

Referring now to 6 becomes the heating in the PM filter assembly 34 shown closer. The exhaust 250 passes through the heater 35 and is through one or more zones of the heater 35 heated. The heated exhaust gas travels a distance "d" and is then removed from the filter 202 added. The distance "d" can be ½ inch (1.27 cm) or less. The filter 202 can have a middle inlet 240 , a channel 242 , a filter material 244 and an outlet 246 have, which is arranged radially outside of the inlet. The filter can be catalysed. The heated exhaust causes combustion of PM in the filter, which regenerates the PM filter. The heater 35 transfers the heat by convection to a front part of the filter 202 to ignite. When the soot in the front surface parts reaches a sufficiently high temperature, the heater is turned off. The combustion of soot then cascades a filter channel 254 down without the Power to the heater must be maintained.

Referring now to 7 Steps for regenerating the PM filter are shown. At step 300 the controller starts and moves to step 304 in front. If the controller at 304 determines that regeneration is required, select the control in step 308 one or more zones and activates the heater in step 312 for the selected zone. At step 316 Based on at least one of: electrical current, voltage, exhaust gas flow, and exhaust gas temperature, the controller estimates a heating period sufficient to achieve a minimum temperature of the filter face. The minimum end face temperature should be sufficient to start soot combustion and create a cascade effect. For example only, the minimum temperature of the face can be set to 700 ° C or more. In one too step 316 alternative step 320 For example, based on a predetermined heating period, exhaust gas flow and exhaust gas temperature, the controller estimates an electrical current and voltage required to reach the minimum temperature of the filter face.

At step 324 the controller determines whether the heating period has ended. When step 324 is affirmative, the controller determines at step 326 whether additional zones need to be regenerated. When step 326 is affirmative, the controller returns to step 308 back. Otherwise the control ends.

at Use determines the control module when the PM filter regeneration requirement. Alternatively, the regeneration can be regular or based on one Event executed become. The control module can estimate when the entire PM filter needs regeneration or when zones need it in the PM filter require regeneration. If the control module determines that the entire PM filter requires regeneration, the control module activates one or more consecutively one after the other the zones to a regeneration in the assigned downstream Part of the PM filter. After this the zone (s) regenerated (s) will become one or more other zones activated while the others are disabled. This procedure will continue until all zones are activated. When the control module determines that one of the zones requires regeneration activates the control module the zone corresponding to the downstream portion of the PM filter corresponds, which requires regeneration.

Referring now to 8A and 8B becomes a zoned inlet heater 400 shown comprising several overlapping layers. The multiple layers are spaced in different planes (ie not coplanar) as in FIG 8B is shown in cross section. If heater zones are as described above in 1 - 7 can be activated, the zones can thermally expand and / or shift. Individual heater zones may be spaced to allow for possible expansion and displacement. Consequently, soot may accumulate between heater zones in the PM filter. Overlapping layers of zones provide regeneration heating at areas of the PM filter that would typically correspond to spaces between heater zones.

The zoned inlet heater 400 can, for example, a first layer 402 (with zones 1, 4 and 5) and a second layer 404 (with zones 2 and 3). The zones of the first layer 402 are arranged in a first plane and the zones of the second layer 404 are arranged in a second plane and from the zones of the first layer 402 spaced. The zones of the first layer 402 overlap the zones of the second layer 404 ,

Referring now to 9A and 9B includes a zoned inlet heater 500 a first layer 502 (with zones 1, 4 and 5), a second layer 504 (with zones 2 and 3) and a third layer 506 (with zones 6 and 7). The zones of the first layer 502 are arranged in a first plane, the zones of the second layer 504 are arranged in a second level and the zones of the third layer 506 are arranged in a third level. All layers 502 . 504 and 506 are spaced from each other. The zones of the first layer 502 the zones overlap each other of the second layer 504 and the third layer 506 ,

As in 8A and 8B As shown, the heater zones are in two different layers. As in 9A and 9B is shown, the heater zones are in three different layers.

Those skilled in the art will understand that other reactions may include two, three, or more heater layers comprising layers arranged in any suitable configuration. The heater zones of each of the layers may be activated and deactivated in any suitable manner as described in the invengers 1 - 7 have been described previous implementations. For example only, the heater zones can be activated one at a time so that when Zone 1 is activated, zones 2-7 are disabled and when Zone 2 is activated, zones 1 and 3-7 are disabled.

In another implementation, zones can be activated simultaneously in non-adjacent layers. Like in 9A and 9B If zone 1 is activated, zone 6 can be activated and zones 2-5 and 7 can be deactivated. In other words, one of the zones in the first layer 502 be activated at the same time as one of the zones in the non-adjacent third layer 506 ,

In another implementation, zones of adjacent layers may be activated simultaneously if there is sufficient space between the zones (ie, the zones of one layer do not overlap the zones of an adjacent layer). Like in 9B is shown, the zones are in the third layer 506 radially from the zones of the second layer 504 spaced. Accordingly, if the zone 2 in the second layer 504 is activated, the zone 7 in the third layer 506 can be activated and the remaining zones 1 and 3-6 can be deactivated. In another implementation, each includes second layer 504 and third layer 506 Zones 2 and 3. The third layer 506 in other words, the same zones as the second layer 504 include.

The The present disclosure may be due to the reduced regeneration time a loss significantly reduce fuel economy, tailpipe temperatures lower and improve system robustness.

Claims (28)

System comprising: a particulate matter (PM) filter, the one upstream located end for receiving exhaust gas and downstream End includes; a zoned heater that from the upstream spaced end and comprising N zones, where N is an integer greater than one, each of the N zones comprising M sub-zones, where M is a integer greater than or equal to one, and where the N zones and the M subzones are arranged in P layers, where P is an integer greater than one is; and a control module that selectively has at least one selected The N zones are activated to regenerate in one of the N zones downstream parts of the PM filter to be triggered, and unselected the N zones disabled. The system of claim 1, wherein at least one of the N zones, which is arranged in a first of the P layers, one second of the N zones overlaps, the is arranged in a second of the P layers. The system of claim 2, wherein the at least one the N zones overlap at least one of the second and third of the N zones, which are arranged in a third of the P layers. The system of claim 1, wherein at least one of the N zones at least one of the M subzones in a first of the P layers and other of the M subzones in a second of the P layers. The system of claim 1, wherein each of the P layers spaced from others of the P layers. The system of claim 1, wherein the non-selected one of N zones provide voltage reduction zones. The system of claim 1, wherein the N zones in a central part, a first circumferential part radially outside the central part and a second circumferential part radially outside of the first rotating part. The system of claim 7, wherein the central part is a first zone comprises and the second circumferential part comprises the first zone, a second zone and a third zone. The system of claim 8, wherein the first, second and alternate third zones around the second rotating part. The system of claim 8, wherein the first circumferential Part fourth and fifth Includes zones that alternate. The system of claim 1, wherein the control module is based on at least two of: the zoned heater supplied Performance, exhaust flow and exhaust temperature estimates a heating period. The system of claim 1, wherein the control module comprises a Heating period for heating a face part of the PM filter to a temperature greater than or equal to a predetermined temperature and zoned Heating device switches off after the heating period. The system of claim 12, wherein the predetermined Temperature 700 ° C is. The system of claim 1, wherein the zoned Heating device at a distance of less than or equal to ½ inch (1.27 cm) is spaced. A method comprising: providing a particulate matter (PM) filter having an upstream end for receiving exhaust gas and a downstream end includes; Arranging a zoned heater spaced from the upstream end comprising N zones, where N is a number greater than one, each of the N zones comprising M sub-zones, M being an integer greater than or equal to one, and wherein N zones and M subzones are arranged in P layers, where P is an integer greater than one; and selectively activating at least a selected one of the N zones to initiate regeneration in portions of the PM filter downstream of the one of the N zones, and disable non-selected ones of the N zones. The method of claim 15, wherein at least one of the N zones, which is arranged in a first of the P layers, a second of the N zones overlaps, which is arranged in a second of the P layers. The method of claim 16, wherein the at least one of the N zones at least one of the second and a third of the N zones overlap, which are arranged in a third of the P layers. The method of claim 15, wherein at least one of the N zones at least one of the M subzones in a first of the P layers and other of the M subzones in a second of the P layers includes. The method of claim 15, wherein each of the P layers spaced from others of the P layers. The method of claim 19, wherein the unselected one of N zones provide voltage reduction zones. The method of claim 19, wherein the N zones in a central part, a first circumferential part radially outside the central part and a second circumferential part radially outside of the first rotating part. The method of claim 21, wherein the central part a first zone and the second circumferential part comprises the first Zone, a second zone and a third zone. The method of claim 22, wherein the first, alternate second and third zones around the second rotating part. The method of claim 22, wherein the first circumferential Part fourth and fifth Includes zones that alternate. The method of claim 19, wherein the control module based on at least two of: the zoned heater supplied power, Exhaust gas flow and exhaust temperature estimates a heating period. The method of claim 19, wherein the control module a heating period for heating a front side part of the PM filter to a temperature greater than or equal to a predetermined temperature and zoned Heating device switches off after the heating period. The method of claim 26, wherein the predetermined Temperature 700 ° C is. The method of claim 15, wherein the zoned Heating device at a distance of less than or equal to ½ inch (1.27 cm) is spaced.