DE102019135832A1 - CATALYST PREHEAT CONTROL DEVICE AND PROCEDURE - Google Patents

Abstract

The present disclosure relates to a catalytic converter preheating control unit (29) for a vehicle (1). The vehicle (1) has an internal combustion engine (2), an exhaust pipe (3), a first catalytic converter (21) for exhaust gas treatment arranged in the exhaust gas line (3), an electrical one arranged in the exhaust gas line (3) upstream of the first catalytic converter (21) Heating element (20) and pumping means for pumping air past the electrical heating element (20). The catalyst preheating control unit (29) includes at least one processor (30) configured to control the electrical heating element (20) for preheating the first catalyst (21); and a memory device having instructions stored therein coupled to the at least one processor (30). The at least one processor (30) is configured to determine a temperature of the first catalytic converter (21). The at least one processor (30) is configured to output an engine start request signal (S2) if the determined temperature of the first catalytic converter (21) is greater than or equal to a predetermined temperature (T1). The present disclosure also relates to a method for controlling the preheating of a first catalytic converter (21) and to a vehicle (1) having a catalytic converter preheating control unit (29).

Description

TECHNICAL PART

The present disclosure relates to an apparatus and method for controlling catalyst preheating. In particular, but not exclusively, the present disclosure relates to a catalyst preheat controller for controlling the preheating of a catalyst in an aftertreatment system. The present disclosure also relates to a vehicle that includes a catalyst preheat control unit and a method of preheating a catalyst.

BACKGROUND

A vehicle is known to provide one or more catalytic converters for treating exhaust gases from an internal combustion engine. The one or more catalysts can be arranged in an aftertreatment system. A known limitation of certain catalysts is the need to reach an elevated operating temperature, referred to herein as the shutdown temperature, before they can operate effectively. Below the switch-off temperature, e.g. after a cold start of the internal combustion engine, the effectiveness of the catalytic converter can be reduced. In order to comply with emissions legislation, it is desirable to heat the catalytic converter as quickly as possible in order to reduce the so-called tailpipe emissions of the vehicle.

The present invention was conceived with this background in mind. In at least certain embodiments, the present invention seeks to overcome or improve at least some of the shortcomings of prior art devices.

SUMMARY OF THE INVENTION

Aspects of the present invention relate to a catalytic converter preheating control device, to a method for preheating a catalytic converter, and to a vehicle as claimed in the appended claims.

• mindestens einen Prozessor, der konfiguriert ist, um das elektrische Heizelement zum Vorwärmen des ersten Katalysators zu steuern; und
• eine Speichervorrichtung mit darin gespeicherten Anweisungen, die mit dem mindestens einen Prozessor gekoppelt ist;
• wobei der mindestens eine Prozessor konfiguriert ist, um eine Temperatur des ersten Katalysators zu bestimmen und ein Motorstartanforderungssignal auszugeben, wenn die bestimmte Temperatur des ersten Katalysators größer oder gleich einer vorbestimmten Temperatur ist. Das Katalysator-Vorwärmungssteuergerät kann konfiguriert werden, um den Start des Verbrennungsmotors einzuleiten, wenn der erste Katalysator eine Temperatur aufweist, die gleich oder größer als die vorbestimmte Temperatur ist. Im Falle eines Elektrofahrzeugs mit mildem Hybrid (MHEV) oder eines Plug-in-Hybridfahrzeugs (PHEV) kann ein elektrischer Fahrmotor ein Drehmoment erzeugen, um das Fahrzeug anzutreiben, wenn der Verbrennungsmotor nicht eingeschaltet ist. Um den ersten Katalysator für den Start des Verbrennungsmotors vorzuwärmen, ist der mindestens eine Prozessor konfiguriert, um das elektrische Heizelement mit Strom zu versorgen. Die Pumpmittel können aktiviert werden, um einen Luftstrom an dem elektrischen Heizelement vorbei zu erzeugen, um die Wärmeübertragung auf den ersten stromabwärts angeordneten Katalysator zu fördern. Das elektrische Heizelement stellt dabei eine Wärmequelle für die Luft dar, die über den ersten Katalysator (und alle anderen Nachbehandlungssysteme) durch die Pumpmittel gepumpt wird. Sobald der erste Katalysator auf eine geeignete Betriebstemperatur erwärmt ist, wird der Motor eingeschaltet. Der erste Katalysator kann auf eine geeignete Betriebstemperatur vorgewärmt werden, was die Emissionen beim Motorstart reduziert. Der erste Katalysator kann beispielsweise ein Dreiwegekatalysator sein.

According to one aspect of the present invention, a catalytic converter preheating control is provided for a vehicle, the vehicle having an internal combustion engine, an exhaust line connected to the internal combustion engine, a first catalytic converter arranged in the exhaust line for exhaust gas treatment, an electrical heating element arranged in the exhaust line upstream of the first catalytic converter and pumping means for pumping air past the electrical heating element; wherein the catalyst preheat control comprises:

• at least one processor configured to control the electrical heating element to preheat the first catalyst; and
• a memory device having instructions stored therein coupled to the at least one processor;
• wherein the at least one processor is configured to determine a temperature of the first catalyst and to output an engine start request signal if the determined temperature of the first catalyst is greater than or equal to a predetermined temperature. The catalyst preheat controller can be configured to initiate the engine start when the first catalyst is at a temperature that is equal to or greater than the predetermined temperature. In the case of a mild hybrid electric vehicle (MHEV) or a plug-in hybrid vehicle (PHEV), an electric traction motor can generate torque to propel the vehicle when the internal combustion engine is not on. In order to preheat the first catalytic converter for starting the internal combustion engine, the at least one processor is configured to supply the electrical heating element with power. The pumping means can be activated to generate a flow of air past the electrical heating element to promote heat transfer to the first downstream catalyst. The electrical heating element represents a heat source for the air, which is pumped through the pumping means via the first catalytic converter (and all other aftertreatment systems). As soon as the first catalytic converter is warmed up to a suitable operating temperature, the engine is switched on. The first catalytic converter can be preheated to a suitable operating temperature, which reduces emissions when the engine is started. The first catalyst can be, for example, a three-way catalyst.

The predetermined temperature can include a threshold temperature. The predetermined temperature can be defined as the operating temperature of the first catalytic converter, for example a switch-off temperature of the first catalytic converter. The specified temperature can be defined, for example, as 150 ° C, 175 ° C, 200 ° C, 225 ° C or 250 ° C. It goes without saying that the predetermined temperature can be calibrated as a function of the properties of the first catalyst. The predetermined temperature can be set permanently or vary over time, for example to take account of changes in the operating temperature of the first catalytic converter due to aging. The catalyst Preheating control can determine the predetermined temperature based on a model of the first catalytic converter, for example in relation to the age and / or the operating conditions of the first catalytic converter.

The catalytic converter preheating control device can be used to start the internal combustion engine as soon as the temperature of the first catalytic converter is equal to the specified temperature. This control strategy can reduce the energy required to keep the first catalyst at or above the predetermined temperature.

The pumping means may include a pump operable to pump air past the electrical heating element. The pump can comprise an electric motor connected to an impeller or a compressor. A special pump can be provided to pump air past the electrical heating element. Alternatively, the pump can also be an electric compressor for supplying compressed air to the internal combustion engine. Alternatively, the pumping means can also be implemented by driving the internal combustion engine without supplying fuel for combustion. An electric motor, such as a starter or a traction motor, can be provided to rotate the internal combustion engine to operate the engine. The electric motor can be driver-connected to the internal combustion engine, e.g. through a mechanical drive coupling. The internal combustion engine can be driven by a torque transmitted from the wheels of the vehicle, for example via a vehicle drive train. For example, the internal combustion engine can be driven afterwards when the combustion is inhibited, e.g. when no fuel is supplied to the combustion chambers. The traction motor can be connected to one or more drive wheels of the vehicle.

The combustion engine can be configured as a range extender for charging the traction battery. In this arrangement, the internal combustion engine can drive a generator for charging the traction battery. The catalytic converter preheating control device can preheat the first catalytic converter and initiate the engine start when the first catalytic converter reaches the predetermined temperature.

The at least one processor can be configured to control the preheating of the first catalytic converter as a function of a state of charge (SOC) of a traction battery for supplying electrical energy to an electric traction motor. The SOC can provide an indication of the time remaining before the internal combustion engine should be started in order to supplement or replace the electric traction motor. The at least one processor can be configured to preheat the first catalyst when the SOC of the traction battery is equal to or less than a predefined threshold value. The catalyst preheating controller can determine when to start preheating the first catalyst based on the SOC of the traction battery.

Alternatively or additionally, the at least one processor can be configured in order to control the preheating of the first catalytic converter as a function of a driver torque request. The catalytic converter preheating control device can determine when to begin preheating the first catalytic converter as a function of the required driver torque.

The at least one processor can be configured to preheat the first catalyst by energizing the electrical heating element. The at least one processor can be configured to de-energize the electrical heating element after starting the internal combustion engine.

The at least one processor can be configured to determine the temperature of the first catalyst by modeling the temperature, for example based on empirical data. Alternatively or additionally, the vehicle can comprise a temperature sensor for measuring a temperature of the first catalytic converter. The at least one processor can be configured to receive a temperature signal from the temperature sensor and to determine the temperature of the first catalyst as a function of the temperature signal.

The at least one processor can be configured to control one or more valves for controlling the supply of air beyond the electrical heating element.

The at least one processor can be configured to control the pump device. The at least one processor can be configured to activate the pumping means to pump air past the electrical heating element in order to preheat the first catalyst.

• Aktivieren des elektrischen Heizelements;
• Betreiben der Pumpmittel, um Luft an dem elektrischen Heizelement vorbei zu pumpen, um den ersten Katalysator vorzuwärmen;
• Bestimmen der Temperatur des ersten Katalysators; und
• Einleiten des Starts des Verbrennungsmotors, wenn die bestimmte Temperatur des ersten Katalysators größer oder gleich einer vorbestimmten Temperatur ist.

According to a further aspect of the present invention, a method for preheating a catalytic converter for a vehicle is provided, wherein the vehicle has an internal combustion engine, an exhaust line connected to the internal combustion engine, a first catalytic converter for exhaust gas treatment arranged in the exhaust line, and one in the exhaust line upstream of the first catalytic converter arranged electrical heating element and pumping means for Pumping air past the electrical heating element; the method comprising:

• Activating the electrical heating element;
• Operating the pumping means to pump air past the electrical heating element to preheat the first catalyst;
• Determining the temperature of the first catalyst; and
• Initiating the start of the internal combustion engine when the specific temperature of the first catalytic converter is greater than or equal to a predetermined temperature.

The vehicle may include a traction battery for supplying electrical energy to an electric traction motor. The method may include controlling the preheating of the first catalytic converter as a function of a state of charge (SOC) of the traction battery. The method can include, for example, determining when to begin preheating the first catalytic converter as a function of the SOC of the traction battery.

The method may include controlling the preheating of the first catalytic converter as a function of a driver torque requirement. The method can include, for example, determining when to begin preheating the first catalytic converter as a function of the driver torque requirement.

The method may include preheating the first catalyst by activating the electrical heating element.

The method may include turning off the electrical heating element after starting the internal combustion engine.

The predetermined temperature can include a threshold temperature. The specified temperature can be defined, for example, as 150 ° C, 175 ° C, 200 ° C, 225 ° C or 250 ° C. It goes without saying that the predetermined temperature can be calibrated as a function of the properties of the first catalyst.

The method may include determining the temperature of the first catalyst by modeling the temperature, for example based on empirical data. Alternatively or additionally, the method can include determining the temperature of the first catalytic converter as a function of a temperature signal from a temperature sensor.

The method may include controlling one or more valves to control the supply of air beyond the electrical heating element.

The method may include controlling the pumping means to pump air past the electrical heating element.

The method may include operating an electric traction motor to drive the internal combustion engine to pump air past the electric heating element.

• wobei das Fahrzeug eine Katalysator-Vorwärmungssteuereinheit wie hierin beschrieben zum Steuern des elektrischen Heizelements zum Vorwärmen des ersten Katalysators umfasst, wobei die Katalysator-Vorwärmungssteuereinheit konfiguriert ist, um den Verbrennungsmotor zu starten, wenn die bestimmte Temperatur des ersten Katalysators größer oder gleich der vorbestimmten Temperatur ist.

According to a further aspect of the present invention, a vehicle is provided which has an internal combustion engine, an exhaust pipe, a first catalyst arranged in the exhaust pipe for exhaust gas treatment, an electrical heating element arranged in the exhaust pipe upstream of the first catalyst and a pumping device for pumping air on the electric Includes heating element over;

• wherein the vehicle comprises a catalyst preheating control unit as described herein for controlling the electrical heating element to preheat the first catalyst, the catalyst preheating control unit being configured to start the internal combustion engine when the determined temperature of the first catalyst is greater than or equal to the predetermined temperature .

The vehicle may include an electric traction motor. The electric traction motor and the internal combustion engine can provide the pump means for pumping air past the electric heating element. The electric traction motor can be operated to drive the internal combustion engine to pump air past the electric heating element. Driving the internal combustion engine may include rotating the internal combustion engine without supplying fuel for combustion. The catalyst preheat controller may control intake and / or exhaust valves within the internal combustion engine to facilitate driving.

The pumping means can comprise an electric compressor for supplying compressed air to the internal combustion engine.

The pumping means may comprise an electric motor connected to an impeller for pumping air past the electric heating element. The pump means can be arranged in a recirculation circuit. For example, the recirculation circuit can be configured to return the air through the aftertreatment system.

The electrical heating element can be arranged in an electrically heated catalytic converter which is arranged upstream of the first catalytic converter.

Any control unit or controller described herein may suitably comprise a computing device having one or more electronic processors. The system can consist of a single control unit or an electronic controller, or alternatively, various functions of the controller can be implemented or housed in different control units or controllers. As used herein, the term “controller” or “control unit” encompasses both a single control unit or controller and a plurality of control units or controllers that are operated together to provide a particular control functionality. In order to configure a controller or control unit, a suitable set of instructions may be provided which, when executed, will cause the control unit or computing device to implement the control techniques described herein. The instruction set can be suitably embedded in the one or more electronic processors. Alternatively, the instruction set can also be provided as software that is stored in one or more memories that are assigned to the controller in order to be executed on the computing device. The control unit or controller can be implemented in software that runs on one or more processors. One or more other control units or controllers can be implemented in software that runs on one or more processors, optionally on the same one or more processors as the first controller. Other suitable precautions can also be taken.

Within the scope of this application, it is expressly provided that the various aspects, embodiments, examples and alternatives set out in the preceding paragraphs, in the claims and / or in the following descriptions and drawings, and in particular the individual features thereof, independently or in any combination can be accepted. That is to say, all embodiments and / or features of an embodiment can be combined in any way and / or combination, unless these features are not compatible. The applicant reserves the right to change an originally filed claim or to file a new claim accordingly, including the right to change an originally filed claim to be dependent on another claim and / or to incorporate a characteristic of another claim, although it was not originally asserted that way.

Figure list

• 1 zeigt eine schematische Darstellung eines Fahrzeugs mit einem Katalysator-Vorheizsteuergerät gemäß einer Ausführungsform der vorliegenden Erfindung;
• 2 zeigt eine schematische Darstellung eines Verbrennungsmotors und einer funktionsfähig gesteuerten Abgasleitung gemäß einer Ausführungsform der vorliegenden Erfindung;
• zeigt eine schematische Darstellung einer alternativen Konfiguration des Verbrennungsmotors und der funktionsfähig gesteuerten Abgasleitung gemäß einer Ausführungsform der vorliegenden Erfindung;
• zeigt eine schematische Darstellung einer weiteren Konfiguration des Verbrennungsmotors und der funktionsfähig gesteuerten Abgasleitung gemäß einer Ausführungsform der vorliegenden Erfindung;
• zeigt eine schematische Darstellung einer noch weiteren Konfiguration des Verbrennungsmotors und der funktionsfähig gesteuerten Abgasleitung gemäß einer Ausführungsform der vorliegenden Erfindung;

One or more embodiments of the present invention will now be described by way of example only with reference to the accompanying persons, in which:

• 1 shows a schematic representation of a vehicle with a catalyst preheat control device according to an embodiment of the present invention;
• 2 shows a schematic representation of an internal combustion engine and a functionally controlled exhaust pipe according to an embodiment of the present invention;
• shows a schematic representation of an alternative configuration of the internal combustion engine and the operably controlled exhaust pipe according to an embodiment of the present invention;
• shows a schematic representation of a further configuration of the internal combustion engine and the functionally controlled exhaust pipe according to an embodiment of the present invention;
• Fig. 10 shows a schematic representation of yet another configuration of the internal combustion engine and the operably controlled exhaust pipe according to an embodiment of the present invention;

DETAILED DESCRIPTION

A vehicle 1 with an internal combustion engine 2 and an exhaust pipe 3 according to one aspect of the present invention, in 1 shown schematically. The internal combustion engine 2 is a compression ignition engine such as a diesel engine. In alternative embodiments, the internal combustion engine 2 a positive ignition engine such as a gasoline engine.

The vehicle 1 in the present embodiment is an automobile, but the present invention can be applied to other types of vehicles. The vehicle 1 includes an electric traction motor 4th that with a traction battery 5 connected is. The electric drive motor 4th is operable to provide tractive effort to propel the vehicle 1 to spend. The electric drive motor 4th is drivingly with a crankshaft of the internal combustion engine 2 connected. The electric drive motor 4th can for example be built into a transmission (not shown) that works with the internal combustion engine 2 connected is. The electric drive motor 4th is operable to the internal combustion engine 2 to turn if the internal combustion engine 2 is not supplied with fuel, which is referred to herein as motor drive.

With reference to 2 instructs the internal combustion engine 2 an air inlet duct 6th and an exhaust outlet 7th on. In operation is the internal combustion engine 2 via the air inlet pipe 6th Air for combustion with fuel in the combustion chamber (s) (not shown) of the internal combustion engine 2 fed. In the air inlet pipe 6th are an electric compressor 8th and a turbocharger 9 arranged to compress the air in the first and second stages. The exhaust gas is from the exhaust outlet 7th into the exhaust pipe 3 pushed out. The exhaust outlet 7th can for example be designed in the form of an exhaust manifold. The electric compressor 8th includes a first impeller 10 and an electric motor 11 . The electric motor 11 is powered to the first impeller 10 driving to rotate. The turbocharger 9 includes a second impeller 12 and one in the exhaust pipe 3 arranged turbine 13th . The turbine 13th is rotated by the expelled exhaust gas and rotates the second impeller 12 driving. In use the electric compressors deliver 8th and the turbocharger 9 the internal combustion engine 2 Air at a pressure higher than atmospheric pressure.

The recirculation of the exhaust gas through the internal combustion engine 2 can reduce emissions such as nitrogen oxides (NOx). A high pressure exhaust gas recirculation line (HP-EGR) line 14th is provided to take high pressure exhaust gas from the exhaust pipe 3 to return. As in 2 shows the HP-EGR line 14th an HP EGR inlet 15th on that between the exhaust outlet 7th of the internal combustion engine 2 and the turbine 13th of the turbocharger 9 is arranged; and an HP EGR outlet 16 that is between the second impeller 12 and the air inlet is arranged. A first heat exchanger 17th and an HP EGR valve 18th are in the HP-EGR line 14th arranged. The first heat exchanger 17th dissipates the heat from the exhaust gas before it goes back into the combustion engine 2 is initiated; and the HP EGR valve 18th controls the recirculation of the high pressure exhaust gas. Part of the high pressure exhaust gas from the internal combustion engine 2 can be selected selectively via the HP-EGR line 14th to be led back.

In the exhaust pipe 3 downstream of the turbocharger 9 is an aftertreatment system 19th intended. The aftertreatment system 19th is configured to take the exhaust from the internal combustion engine 2 to be treated, for example to reduce the emissions of carbon monoxide (CO), hydrocarbons (HC) and nitrogen oxide (NOx). The aftertreatment system 19th includes an electrical heating element 20th and at least one first catalyst 21st . The first catalyst 21st is in the exhaust pipe 3 downstream of the electrical heating element 20th arranged. As described herein, the electrical heating element functions 20th to get the first catalyst 21st before starting the internal combustion engine 2 to preheat. In particular, the electrical heating element 20th configured to the first catalyst 21st to a predetermined temperature threshold T1 to preheat. The specified temperature threshold T1 can, for example, a switch-off temperature of the first catalyst 21st correspond. In the present embodiment, the electrical heating element is 20th into an electrically heated catalyst 22nd integrated. It goes without saying that the aftertreatment system 19th may sensibly contain additional components and / or devices for exhaust gas treatment prior to release into the atmosphere.

A low pressure exhaust gas recirculation line (LP-EGR) 24 is provided to remove low pressure exhaust gas from the exhaust pipe 3 to the air inlet pipe 6th of the internal combustion engine 2 to return. As in 2 shown shows the LP-EGR line 24 an LP-EGR inlet 25th on, the downstream of the first catalyst 21st is arranged, and an LP-EGR outlet 26th that is upstream of the first impeller 10 is arranged. A second heat exchanger 27 and an LP-EGR valve 28 are in the LP-EGR line 24 arranged. The second heat exchanger 27 dissipates the heat from the exhaust gas before it goes back into the combustion engine 2 is initiated; and the LP-EGR valve 28 controls the recirculation of the low-pressure exhaust gas. Part of the low pressure exhaust gas from the internal combustion engine 2 can selectively through the LP-EGR line 24 to be led back.

The vehicle 1 includes a catalyst preheat control unit 29 for controlling the operation of the electrical heating element 20th to preheat the first catalyst 21st . The catalyst preheat control unit 29 includes a processor 30th having a storage device 31 connected is. A set of non-volatile calculation instructions is stored on the storage device 31 saved. When the calculation instructions are executed, they cause the processor 30th to carry out the methods described herein. A temperature sensor 32 that is in the first catalyst 21st is arranged, outputs a first temperature signal ST1 to the processor 30th off to get an indication of the temperature of the first catalyst 21st to deliver. A first temperature threshold T1 is in the storage device 31 stored, and when used the processor compares 30th the measured temperature of the first catalyst 21st with the first temperature threshold T1 . The first temperature threshold T1 can, for example, a switch-off temperature of the first catalyst 21st correspond to, ie a temperature at which the first catalyst 21st is activated. As an example, the first temperature threshold T1 defined as 150 ° C become. It should be noted that the first temperature threshold T1 depending on the properties of the first catalyst 21st , in particular the shutdown temperature of the first catalyst 21st , can be calibrated. The shutdown temperature can vary depending on the catalyst used, but is a typical first temperature threshold T1 is in the range from 150 ° C to 250 ° C. It is understood that the temperature of the first catalyst 21st can be modeled, for example as a function of the operating parameters of the electrical heating element 20th .

The electric heating element 20th is energized to the first catalyst 21st before starting the internal combustion engine 2 to preheat. As described above, the first catalyst is 21st in the exhaust pipe 3 downstream of the electrical heating element 20th arranged. The catalyst preheating control unit 29 is configured to use the electrical heating element 20th to be supplied with electricity and thereby the temperature of the electrically heated catalyst 22nd to warm up. In use, air is passed through the electrically heated catalyst 22nd pumped and through the electric heating element 20th warmed up. The heated air is through the first catalyst 21st pumped and the heat is applied to the first catalyst 21st transfer. The temperature sensor 32 measures the temperature of the first catalyst 21st and outputs the first temperature signal ST to the processor 30th out. The catalyst preheating control unit 29 monitors the temperature of the first catalyst 21st . When the temperature of the first catalyst 21st equal to the first temperature threshold T1 is, gives the processor 30th an engine start request signal S2 off to initiate engine start. In the present embodiment, the engine start request signal is S2 to an engine control unit 33 output indicating the operation of the internal combustion engine 2 and the electric drive motor 4th controls. The engine control unit 33 is configured to provide a motor control signal S3 and a traction motor control signal S4 to spend. The engine control unit 33 is configured to the internal combustion engine 2 upon receipt of the engine start request signal S2 from the catalyst preheat control unit 29 to start. The detailed functionality of the engine control unit 33 is beyond the scope of the present disclosure. It should be noted that, in alternative embodiments, the catalyst preheat controller 29 in the engine control unit 33 can be installed.

The catalyst preheating control unit 29 serves to preheat the first catalytic converter 21st before starting the internal combustion engine 2 . The first catalyst 21st can before a cold start of the internal combustion engine 2 be preheated. In certain embodiments, the vehicle can 1 exclusively from the electric drive motor 4th are driven. The catalyst preheating control unit 29 can be configured to use the first catalyst 21st preheat while the vehicle 1 from the electric drive motor 4th is driven. When the internal combustion engine 2 is stopped for a certain period of time, the catalyst preheating control unit 29 the first catalyst 21st before restarting the combustion engine 2 preheat, for example when the temperature of the first catalyst 21st below the specified temperature threshold T1 falls.

The catalyst preheating control unit 29 can be configured to preheat the first catalyst 21st depending on a certain state of charge (SOC) of the traction battery 5 initiate. For example, the catalytic converter preheating control unit 29 configured to initiate pre-heating when the particular SOC drops to a pre-defined threshold. The threshold value can for example be defined in such a way that it is ensured that in the traction battery 5 Sufficient energy is available to operate the electric traction motor 4th maintain while the first catalyst 21st before restarting the combustion engine 2 is preheated to a temperature above or equal to a switch-off temperature. Other factors by the catalyst preheat controller 29 can be used are one or more of the following: a discharge rate, an actual driver demand, a predicted driver demand, and a remaining driving time. The processor 30th can be configured to set a target time for restarting the internal combustion engine 2 to determine a torque for propelling the vehicle 1 to be generated (either in conjunction with or instead of the electric traction motor 4th ). The target time can, for example, depend on the SOC of the traction battery 5 and / or a driver torque requirement can be determined. The driver torque requirement can be determined as a function of a torque request signal STQ, for example output by a pedal position sensor for an accelerator pedal of the vehicle 1 . The processor 30th can control the preheating of the first catalytic converter as a function of the determined target time. The processor 30th can for example initiate preheating, so that the temperature of the first catalyst 21st greater than or equal to the temperature threshold T1 is at (or before) the specified target time. Because the first catalyst 21st has been preheated, the aftertreatment system works 19th when starting the internal combustion engine 2 .

The exhaust pipe 3 and the air inlet duct 6th can have various configurations so that air passes to the electrical heating element 20th and through the first catalyst 21st can be pumped past. These different embodiments will now be described with reference to the escorts.

In the in 2 The embodiment shown is an engine bypass line 34 provided to the internal combustion engine 2 during preheating of the first catalyst 21st to bypass. The engine bypass line 34 includes a bypass inlet 35 , a bypass outlet 36 and a bypass control device 37 . The bypass inlet 35 is in the air inlet pipe 6th between the electric compressor 8th and the turbocharger 9 arranged. The bypass outlet 36 is in the exhaust pipe 3 before the aftertreatment system 19th arranged. The catalyst preheat control unit 29 is configured to receive a bypass valve control signal S5 to control the operation of the bypass control valve 37 to spend. The bypass control valve 37 prevents the electric compressor 8th into the exhaust pipe 3 instead of compressing the inlet charge. In the present embodiment, the electric compressor 8th operated to air through the aftertreatment system 19th to pump. In particular, the catalyst preheat control unit 29 is configured to generate an electrical compressor control signal S6 to control the electric compressor 8th to spend.

The catalyst preheating control unit determines the operation 29 when the internal combustion engine 2 should be started. The catalyst preheat control unit 29 gives the bypass valve control signal S5 off to the bypass control valve 37 to open; and the electrical compressor control signal S6 to the electric compressor 8th to activate. The catalyst preheat control unit 29 also gives the electrical heating control signal S1 off to the electric heating element 20th energize so that the on the electric heating element 20th passing air is heated. The catalyst preheating control unit 29 receives the first temperature signal ST and monitors the temperature of the first catalyst 21st . When the temperature of the first catalyst 21st equal to the first temperature threshold T1 the catalytic converter preheat control unit gives 29 the engine start request signal S2 to the engine control unit 33 out. In response to the engine start request signal S2 gives the engine control unit 33 the motor control signal S3 to start the internal combustion engine 2 out. The catalyst preheating control unit 29 also switches the electrical heating element 20th de-energized to preheat the first catalytic converter 21st to end.

In the in 3 The illustrated embodiment is the HP-EGR line 14th used to the internal combustion engine 2 during the preheating of the first catalyst 21st to bypass. The catalyst preheating control unit 29 is configured to receive a bypass valve control signal S5 to control the operation of the HP EGR valve 18th to spend. The electric compressor 8th is operated to air through the aftertreatment system 19th to pump. In particular, is the catalyst preheat control unit 29 configured to use an electrical compressor control signal S6 to control the electric compressor 8th to spend.

The catalyst preheating control unit determines the operation 29 when the internal combustion engine 2 should be started. The catalyst preheat control unit 29 gives the bypass valve control signal S5 to open the HP-EGR valve 18th and the electrical compressor control signal S6 to activate the electric compressor 8th out. The catalyst preheat control unit 29 also gives the electrical heating control signal S1 off to the electric heating element 20th energize so that the on the electric heating element 20th passing air is heated. The catalyst preheating control unit 29 receives the first temperature signal ST and monitors the temperature of the first catalyst 21st . When the temperature of the first catalyst 21st equal to the first temperature threshold T1 the catalytic converter preheat control unit gives 29 the engine start request signal S2 to the engine control unit 33 out. In response to the engine start request signal S2 gives the engine control unit 33 the motor control signal S3 to start the internal combustion engine 2 out. The catalyst preheating control unit 29 also switches the electrical heating element 20th de-energized to preheat the first catalytic converter 21st to end.

In the in 4th The embodiment shown is the electric traction motor 4th operated to the internal combustion engine 2 during the preheating of the first catalyst 21st to motorize. This is where the internal combustion engine is 2 used to air the electric heating element 20th pumping over. The catalyst preheat control unit 29 is configured to receive a traction motor control signal S7 to the engine control unit 33 to spend. The engine control unit 33 activates the electric drive motor 4th without the internal combustion engine 2 To supply fuel to run the engine.

The catalyst preheating control unit determines the operation 29 when the internal combustion engine 2 should be started. The catalyst preheating control unit 29 gives the drive motor control signal S7 off to require the engine control unit 33 the electric drive motor 4th activated. The engine control unit 33 can be configured to include intake and exhaust valves within the internal combustion engine 2 open to pumping air from the air inlet line 6th into the exhaust pipe 3 to facilitate. The catalyst preheat control unit 29 also gives the electrical heating control signal S1 off to the electric heating element 20th energize so that the on the electric heating element 20th passing air is heated. The catalyst preheating control unit 29 receives the first temperature signal ST and monitors the temperature of the first catalyst 21st . When the temperature of the first catalyst 21st equal to the first temperature threshold T1 the catalytic converter preheat control unit gives 29 the engine start request signal S2 to the engine control unit 33 out. In response to the engine start request signal S2 gives the engine control unit 33 the motor control signal S3 to start the internal combustion engine 2 out. The catalyst preheating control unit 29 also switches the electrical heating element 20th de-energized to preheat the first catalytic converter 21st to end.

In each of the aforementioned embodiments, the LP-EGR line 24 used to heat the air during the preheating of the first catalyst 21st to return. The LP-EGR line 24 can be used as a recirculation line to preheat the first catalyst 21st to facilitate. In particular, the catalytic converter preheating control device 29 configured to use the LP EGR valve 28 to open so that the heated air can be returned. The electric heating element 20th can be energized to stop the electrical heating element 20th heat pumped over air. The heated air can then pass through the air inlet duct 6th instead of from the exhaust pipe 3 to get into the atmosphere. The HP EGR valve 18th and the LP-EGR valve 28 can both be opened to the internal combustion engine 2 to bypass and at least some of the heated air downstream of the first catalyst 21st through the exhaust pipe 3 to redirect.

In the in 5 The embodiment shown is a special recirculation line 38 to return the heated air through the aftertreatment system 19th intended. A special recirculation pump 39 is provided to the heated air during the preheating of the first catalyst 21st through the recirculation line 38 after treatment to circulate. The catalyst preheat control unit 29 is configured to have a control signal S8 of the circulation pump to operate the circulation pump 39 to control. Optionally, a control valve (not shown) can be provided to regulate the air flow through the recirculation line 38 control of aftercare.

The catalyst preheating control unit determines the operation 29 when the internal combustion engine 2 should be started. The catalyst preheating control unit 29 gives the control signal S8 the circulation pump off to the circulation pump 39 to activate. The recirculation pump 39 is operated to air through the aftertreatment system 19th to pump. The catalyst preheat control unit 29 also gives the electrical heating control signal S1 off to the electric heating element 20th energize so that the on the electric heating element 20th passing air is heated. The recirculation pump 39 continues to work to circulate the heated air through the recirculation line 38 after treatment to circulate. The catalyst preheating control unit 29 receives the first temperature signal ST and monitors the temperature of the first catalyst 21st . When the temperature of the first catalyst 21st equal to the first temperature threshold T1 the catalytic converter preheat control unit gives 29 the engine start request signal S2 to the engine control unit 33 out. In response to the engine start request signal S2 gives the engine control unit 33 the motor control signal S3 to start the internal combustion engine 2 out. The catalyst preheating control unit 29 also switches the electrical heating element 20th de-energized to preheat the first catalytic converter 21st to end. The catalyst preheating control unit 29 also deactivates the circulation pump 39 . In addition to or instead of the electrical heating element 20th can in the recirculation line 38 a separate heating element can be provided for after-treatment.

It is understood that various changes and modifications can be made to the embodiments described herein without departing from the scope of the present invention.

It should be noted that the techniques described herein apply to a vehicle 1 can be used that do not have an electric drive motor 4th includes. For example, it can be advantageous to use the first catalyst 21st in a vehicle 1 preheat that is configured to include a stop / start control strategy for the internal combustion engine 2 to implement. Alternatively, or in addition, the techniques can be applied to a vehicle that is configured to implement a “glide” or “coasting control strategy” in which the internal combustion engine 2 while driving the vehicle 1 can be stopped, for example while driving down a slope.

Claims (21)

A catalyst preheating control unit for a vehicle, the vehicle having an internal combustion engine, an exhaust line connected to the internal combustion engine, a first catalyst arranged in the exhaust line for exhaust gas treatment, an electrical heating element arranged in the exhaust line upstream of the first catalyst and pumping means for pumping air via the electric Having heating element; wherein the catalyst preheat control unit comprises: at least one processor configured to control the electrical heating element to preheat the first catalyst; and a memory device having instructions stored therein coupled to the at least one processor; wherein the at least one processor is configured to determine a temperature of the first catalyst and to output an engine start request signal if the determined temperature of the first catalyst is greater than or equal to a predetermined temperature. Catalytic converter preheating control unit after Claim 1 wherein the at least one processor is configured to control preheating of the first catalyst based on a state of charge (SOC) of a traction battery for supplying electrical energy to an electric traction motor. Catalytic converter preheating control unit after Claim 1 or Claim 2 wherein the at least one processor is configured to control preheating of the first catalyst based on a requirement for driver torque. Catalyst preheating control unit according to one of the Claims 1 , 2 or 3 wherein the at least one processor is configured to preheat the first catalyst by energizing the electrical heating element. A catalyst pre-heating control unit as claimed in any preceding claim, wherein the vehicle comprises a temperature sensor for measuring a temperature of the first catalyst; wherein the at least one processor is configured to receive a temperature signal from the temperature sensor and to determine the temperature of the first catalyst in dependence on the temperature signal. A catalyst preheat control unit as claimed in any preceding claim, wherein the at least one processor is configured to control one or more valves to control air flow past the electrical heating element. A catalyst preheat control unit as claimed in any preceding claim, wherein the at least one processor is configured to control the pump means. A method for preheating a catalytic converter for a vehicle, wherein the vehicle has an internal combustion engine, an exhaust line connected to the internal combustion engine, a first catalytic converter arranged in the exhaust line for exhaust gas treatment, an electrical heating element arranged in the exhaust line upstream of the first catalytic converter and pumping means for pumping air the electrical heating element, the method comprising: Activating the electrical heating element; Operating the pumping means to pump air past the electrical heating element to preheat the first catalyst; Determining the temperature of the first catalyst; and Initiating the start of the internal combustion engine when the specific temperature of the first catalytic converter is greater than or equal to a predetermined temperature. Procedure according to Claim 8 wherein the vehicle includes a traction battery for supplying electrical power to an electric traction motor; wherein the method comprises controlling the preheating of the first catalytic converter as a function of a state of charge of the traction battery. Procedure according to Claim 8 or Claim 9 comprising controlling the preheating of the first catalytic converter as a function of a driver torque demand. Method according to one of the Claims 8 , 9 or 10 comprising preheating the first catalyst by activating the electrical heating element. Method according to one of the Claims 8 to 11 wherein the temperature of the first catalyst is determined as a function of a temperature signal from a temperature sensor. Method according to one of the Claims 8 to 12 comprising controlling one or more valves to control the supply of air beyond the electrical heating element. Method according to one of the Claims 8 to 13th comprising controlling the pumping means to pump air past the electrical heating element. Method according to one of the Claims 8 to 14th comprising operating an electric traction motor to drive the internal combustion engine to pump air past the electric heating element. A vehicle comprising an internal combustion engine, an exhaust pipe, a first catalyst disposed in the exhaust pipe for treating exhaust gas, an electrical heating element disposed in the exhaust pipe upstream of the first catalyst, and a pumping device for pumping air on the electrical heating element past; wherein the vehicle includes a catalyst pre-heating control unit according to any one of Claims 1 to 7th for controlling the electric heater to preheat the first catalyst, wherein the catalyst preheat control unit is configured to start the internal combustion engine when the determined temperature of the first catalyst is greater than or equal to the predetermined temperature. Vehicle after Claim 16 comprising an electric traction motor, the electric traction motor and the internal combustion engine providing the pumping means for pumping air past the electrical heating element, the electric traction motor being operable to motorize the internal combustion engine and to pump air past the electrical heating element. Vehicle after Claim 16 wherein the pump means comprises an electric compressor for supplying compressed air to the internal combustion engine Vehicle after Claim 16 wherein the pumping means comprises an electric motor connected to an impeller for pumping air past the electric heating element. Vehicle after Claim 19 , wherein the pump device is arranged in a recirculation circuit Vehicle after one of the Claims 16 to 20th wherein the electrical heating element is disposed in an electrically heated catalyst disposed upstream of the first catalyst.

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