JP2013133755A - Control device of internal combustion engine - Google Patents

Abstract

Power generated by an energy regeneration device is effectively distributed to heating a catalyst device and a reducing agent supply device.
A recovery control device is an exhaust purification means having a catalyst for purifying exhaust discharged from a combustion chamber of an internal combustion engine, and can adjust the temperature of the catalyst according to the magnitude of electric power supplied. Exhaust gas purification means having such a structure, power storage means capable of supplying electric power to the exhaust gas purification means, electric power can be regenerated according to the operating state of the internal combustion engine, and the regenerated electric power is exhausted Power regeneration means capable of supplying at least one of the purification means and the power storage means. Even if the regenerated electric power is to be supplied to the exhaust gas purification means 220, the control device regenerates if the condition 240 that the catalyst temperature is equal to or higher than a predetermined threshold temperature is satisfied. It is configured so that power is prohibited from being supplied to the exhaust gas purification means.
[Selection] Figure 2

Description

  The present invention relates to a control device for an internal combustion engine that is applied to an internal combustion engine having a configuration capable of regenerating electric power in accordance with the operating state of the internal combustion engine.

  Conventionally, an internal combustion engine having a configuration capable of converting kinetic energy of the vehicle into electric energy and recovering (regenerating power) during a period in which the vehicle equipped with the internal combustion engine is decelerating has been proposed. ing. As this type of internal combustion engine, for example, an internal combustion engine having a configuration for regenerating electric power using an alternator provided in the vehicle and a motor as a drive source provided in the vehicle (such as a hybrid vehicle and an electric vehicle) are the same. There has been proposed an internal combustion engine that is configured to operate as a generator according to the driving state of a vehicle (for example, when a regenerative brake is operated) and to regenerate electric power.

  One conventional control device (hereinafter also referred to as “conventional device”) applied to an internal combustion engine having the above-described configuration is a configuration capable of regenerating electric power and purifies exhaust gas. (The exhaust purification efficiency depends on the temperature of the catalyst), an electric heater for heating the catalyst, and a battery that can be charged and discharged. The conventional device first supplies (charges) the regenerated electric power to the battery, and supplies the electric power to the electric heater after the charging rate of the battery reaches a predetermined value. Thus, the conventional apparatus is designed to increase both the battery charging rate and the catalyst temperature (exhaust purification efficiency) as much as possible (see, for example, Patent Document 1).

JP 2009-255877 A

  As described above, the conventional apparatus selects both the regenerative power supply target in consideration of both the battery charging rate and the exhaust purification efficiency. On the other hand, as is well known, the exhaust purification efficiency may not necessarily be higher as the temperature of the catalyst is higher.

  For example, when the temperature of the catalyst becomes excessively high beyond the range of an appropriate temperature (hereinafter also referred to as “activation temperature”) from the viewpoint of sufficiently exerting the function as the catalyst, the exhaust gas is sufficiently exhausted by the catalyst. It is thought that it may not be purified. In this case, the emission amount (emission emission amount) of substances such as nitrogen oxides and particulate matter contained in the exhaust gas to the outside of the internal combustion engine may not be appropriately reduced.

  In view of the above problems, an object of the present invention is to provide a control device for an internal combustion engine that can reduce the emission emission as much as possible while utilizing the regenerated electric power as effectively as possible.

An internal combustion engine control apparatus according to the present invention for solving the above-described problems is provided as follows.
An “exhaust gas purifying unit comprising an exhaust gas purifying unit having a catalyst for purifying exhaust gas discharged from a combustion chamber of an internal combustion engine and capable of adjusting the temperature of the catalyst according to the magnitude of electric power supplied. "When,
"Power storage means" capable of supplying power to the exhaust purification means,
“Electric power regeneration means” capable of regenerating electric power according to the operating state of the internal combustion engine and capable of supplying the regenerated electric power to at least one of the exhaust gas purification means and the power storage means. When,
Is provided.

  The “catalyst” is not particularly limited as long as it can purify the purification target component contained in the exhaust gas introduced into the catalyst. For example, as a catalyst, an SCR (Selective Catalytic Reduction) catalyst having a structure in which a catalyst component (zeolite catalyst, vanadium catalyst, etc.) is supported on a carrier (ceramics, etc.), a catalyst component (noble metal, etc.), an oxygen storage substance, and NOx NOx occlusion reduction catalyst in which a storage material is supported on a carrier, a diesel particulate filter that collects particulate matter, an oxidation catalyst that can oxidize nitrogen oxides contained in exhaust gas, and nitrogen oxide and particulate matter A DPNR (Diesel Particulate-NOx Reduction) catalyst capable of removing both from the exhaust gas, or the like may be employed. Note that “purifying the purification target component” means that at least a part of the purification target component is removed from the exhaust gas, and does not necessarily mean that all of the purification target component is removed from the exhaust gas.

  The “exhaust gas purification means” is not particularly limited as long as it has the catalyst. For example, when a plurality of members (for example, an oxidation catalyst, a diesel particulate filter, an SCR catalyst, etc.) for purifying exhaust gas are provided in the exhaust passage of the internal combustion engine, the exhaust gas purification means includes the plurality of members. May be meant as individual members, or the whole exhaust gas purification system composed of the plurality of members.

  The “configuration capable of adjusting the temperature of the catalyst” is not particularly limited as long as it is a configuration capable of adjusting the temperature of the catalyst directly or indirectly. For example, as a configuration capable of adjusting the temperature of the catalyst, a configuration in which the temperature of the catalyst is adjusted by a method such as heating the catalyst itself (for example, an electric heater provided so as to surround the catalyst), and the catalyst A configuration in which the temperature of the catalyst is adjusted by a method such as heating the introduced exhaust gas (for example, an electric heater provided at a position upstream of the exhaust passage from the catalyst) may be employed. It should be noted that “tuning” the temperature of the catalyst includes increasing the temperature of the catalyst, decreasing the temperature of the catalyst, and maintaining the temperature of the catalyst at a specific temperature.

  The “power storage means” is not particularly limited as long as it can be charged and discharged. For example, a battery having a predetermined capacity may be employed as the power storage means.

  The “operating state of the internal combustion engine” is an operating state having some relationship with the state of the regenerated electric power (for example, whether or not electric power can be regenerated and the magnitude of the regenerated electric power). Alternatively, it may be any index as long as it is an index representing the same operating state, and is not particularly limited. For example, a parameter representing a running state of a vehicle equipped with the internal combustion engine (for example, whether the vehicle is accelerating or decelerating) may be employed as the operating state of the internal combustion engine.

  The power regeneration means may be configured to be able to supply the selectively regenerated power to either the exhaust purification means or the power storage means, and may be able to supply the regenerated power to both of them simultaneously. It may be configured as follows.

Furthermore, the control device of the present invention provides:
Even when the regenerated electric power is to be supplied to the exhaust gas purification means, the regenerated electric power is satisfied if the condition that the temperature of the catalyst is equal to or higher than a predetermined threshold temperature is satisfied. It is configured such that power is “prohibited” from being supplied to the exhaust gas purification means.

  According to the above configuration, even if the regenerated electric power is to be supplied to the exhaust gas purification unit in preference to the power storage unit (for example, when the power storage unit has a power storage level equal to or higher than a predetermined level) When the temperature of the catalyst is considered to be excessively high, the temperature of the catalyst cannot be increased. Therefore, the control device of the present invention having the above configuration can reduce the emission emission as much as possible while utilizing the regenerated electric power as effectively as possible.

  By the way, the “case where the regenerated electric power is to be supplied to the exhaust gas purification means” is not particularly limited as long as it is determined according to the state of the member using the regenerated electric power. For example, as a case where the regenerated electric power is to be supplied to the exhaust gas purification unit, a case where the degree of power storage (for example, the charging rate) in the power storage unit is equal to or higher than a predetermined value may be employed.

  The “charge rate” is an index indicating the state of charge of the power storage means. That is, a charging rate of 0% represents a state in which the electrical energy stored in the power storage means is zero, and a charging rate of 100% indicates that the electrical energy stored in the power storage means is stored in the power storage means. Represents the maximum amount that can be stored.

  The above-mentioned “condition that the temperature of the catalyst is equal to or higher than a predetermined threshold temperature” is the time before the regenerated electric power is supplied to the exhaust gas purifying means, or the regenerated electric power is supplied to the exhaust gas purifying means. The conditions are not particularly limited as long as the temperature of the catalyst at a later time is taken into consideration. For example, as a condition that the temperature of the catalyst is equal to or higher than a predetermined threshold temperature, the temperature (current temperature) of the catalyst before the regenerated electric power is supplied is equal to or higher than the predetermined threshold temperature, or the exhaust gas is exhausted. The temperature obtained by adding the amount of increase in the temperature of the catalyst (predicted increase) due to the supply of the regenerated electric power to the purification means to the temperature of the catalyst before the electric power is supplied (predicted) One or both of the above may be employed. Further, for example, as the above condition, one or both of the current exhaust gas temperature being equal to or higher than a predetermined threshold temperature and the predicted exhaust gas temperature being equal to or higher than a predetermined threshold temperature may be employed. The method for obtaining the catalyst temperature and the exhaust gas temperature is not particularly limited. These temperatures may be measured, for example, by temperature sensors or may be estimated based on specific operating parameters of the internal combustion engine.

  The “threshold temperature” is not particularly limited as long as it is determined in consideration of the exhaust gas purification efficiency by the catalyst. For example, an appropriate value can be adopted as the threshold temperature that can be determined that the purification efficiency of a specific purification target component contained in the exhaust gas is lower than a desired value when the temperature of the catalyst is equal to or higher than the threshold temperature.

  Next, some aspects (Aspect A and Aspect B) of the control device of the present invention will be described.

・ Aspect A
In the control device of the present invention, when the regenerated electric power is prohibited from being supplied to the exhaust gas purification means, the target to which the regenerated electric power is supplied is not particularly limited.

For example, as an example of a specific configuration, the control device of the present invention is
The catalyst is "a catalyst that purifies the exhaust gas by reducing nitrogen oxides contained in the exhaust gas",
“Reducing agent supply” is a reducing agent supply means for supplying a reducing agent into the exhaust gas introduced into the catalyst, and is capable of adjusting the temperature of the reducing agent according to the magnitude of the supplied electric power. Means "
When the regenerated electric power is prohibited from being supplied to the exhaust gas purification unit, the regenerated electric power can be supplied to the “reducing agent supply unit”.

  In the above configuration, the exhaust gas is purified by the reaction between the reducing agent supplied from the reducing agent supply means into the exhaust gas and the nitrogen oxide in the exhaust gas in the catalyst. Therefore, in order to efficiently purify the exhaust gas, the reducing agent is appropriately supplied into the exhaust gas from the reducing agent supply means (for example, the amount of the supplied reducing agent and the dispersion of the supplied reducing agent into the exhaust gas). It is considered preferable to be supplied (in terms of degree, etc.). On the other hand, for example, the flow of the reducing agent is significantly reduced (for example, the reducing agent is frozen or a specific component is deposited in the reducing agent). It is not desirable that the reducing agent is not properly supplied into the exhaust from the means.

  Therefore, according to the above configuration, when the regenerated electric power is prohibited from being supplied to the exhaust gas purification unit, the regenerated electric power is supplied to the reducing agent supply unit. In other words, the target (exhaust gas purification means or reducing agent supply means) to which the regenerated electric power is supplied is changed according to the temperature of the catalyst. Thereby, even if it is a case where the fluidity | liquidity of a reducing agent is falling (for example, at the time of cold start), the fluidity | liquidity of a reducing agent can be improved rapidly. Therefore, in the control device of this aspect, the emission emission can be reduced as much as possible while the regenerated electric power is utilized as effectively as possible.

  The “reducing agent supply means” is not particularly limited as long as it can supply the reducing agent into the exhaust gas until the exhaust gas discharged from the combustion chamber of the internal combustion engine is introduced into the catalyst. Not. For example, as a reducing agent supply means, an injection valve for injecting the reducing agent into the exhaust, a pipe for supplying the reducing agent to the injection valve, a reducing agent tank to which the pipe is connected, and the injection valve and A reducing agent supply system including an electric heater for heating the pipe or the like may be employed. Furthermore, for example, an injection valve incorporating an electric heater may be employed as the reducing agent supply means. In addition, the position where the reducing agent supply means is provided is not particularly limited as long as it can supply the reducing agent to the exhaust gas introduced into the catalyst. For example, the reducing agent supply means can be provided at a position upstream of the catalyst in the exhaust passage of the internal combustion engine.

  The “upstream side” represents a direction corresponding to the direction opposite to the movement direction of the exhaust gas when the exhaust gas moves in the exhaust passage. For example, “a position upstream from the catalyst” represents a position closer to the combustion chamber than a position where the catalyst is provided. On the contrary, the “downstream side” represents a direction corresponding to the moving direction of the exhaust when the exhaust moves in the exhaust passage. For example, “a position downstream of the exhaust purification unit” represents a position farther from the combustion chamber of the internal combustion engine than a position where the exhaust purification unit is provided.

  The “reducing agent” is not particularly limited as long as it contains a substance capable of reducing nitrogen oxides contained in exhaust gas (or a substance capable of reducing nitrogen oxides can be generated from the reducing agent). As the reducing agent, for example, an aqueous urea solution and ammonia can be employed.

  As described above, the concept of control in the case where “the regenerated power is to be supplied to the exhaust purification means is prohibited from being supplied to the exhaust purification means” has been described. It was. Next, the concept of control in the case where “the regenerated electric power is not prohibited from being supplied to the exhaust gas purification means” will be described.

・ Aspect B
When the regenerated electric power is supplied to the exhaust gas purification unit, not all of the regenerated electric power is necessarily supplied to the exhaust gas purification unit. For example, when a plurality of members are involved in the purification of exhaust gas, the regenerated electric power can be supplied to the members in the order that the exhaust gas can be purified as efficiently as possible.

Therefore, for example, as an example of a specific configuration, the control device of the present invention is
In the case where the regenerated electric power is to be supplied to the exhaust gas purification means, if the “condition that the fluidity of the reducing agent is smaller than a predetermined degree” is satisfied, the regenerated electric power is It may be configured to be supplied to the reducing agent supply unit in preference to the exhaust purification unit.

  According to the above configuration, when the flowability of the reducing agent is reduced, the regenerated electric power is supplied to the reducing agent supply means before the electric power regenerated to the exhaust gas purification means is supplied. . As a result, compared with the case where the previously regenerated electric power is supplied to the exhaust purification means (the exhaust purification efficiency by the catalyst is increased, but the reducing agent may not be supplied properly), the exhaust purification means is concerned. As a whole member, the exhaust gas purification efficiency can be improved.

  In addition, when electric power can be further supplied from the electric power regeneration means after the electric power regenerated is supplied to the reducing agent supply means (for example, when the rest of the electric power regenerated is supplied), the control device of this aspect is The regenerated electric power can be configured to be supplied to the exhaust gas temperature adjusting means.

  By the way, the above-mentioned “conditions for reducing the fluidity of the reducing agent to be smaller than a predetermined degree” are not particularly limited as long as the parameters are related to the parameters related to the fluidity of the reducing agent. For example, as a condition that the fluidity of the reducing agent is smaller than a predetermined degree, the temperature of the reducing agent injection valve is lower than a predetermined temperature, the temperature of the reducing agent is lower than a predetermined temperature, reduction At least one of the fact that the temperature outside the vehicle on which the agent supply means is mounted is equal to or lower than a predetermined temperature may be employed.

  As described above, the control device for an internal combustion engine according to the present invention has an effect that the emission emission amount can be reduced as much as possible while utilizing the regenerated electric power as effectively as possible.

1 is a schematic view of an internal combustion engine to which a control device according to a first embodiment of the present invention is applied. It is a schematic flowchart which shows the view of control in the control apparatus which concerns on 1st Embodiment of this invention. It is a time chart which shows the relationship between the vehicle speed in the control apparatus which concerns on 2nd Embodiment of this invention, a charging rate, various flags, and the temperature of an SCR catalyst. It is the flowchart which showed the routine which CPU of the control apparatus which concerns on 2nd Embodiment of this invention performs. It is the flowchart which showed the routine which CPU of the control apparatus which concerns on 2nd Embodiment of this invention performs. It is a time chart which shows the relationship between the vehicle speed in the control apparatus which concerns on 3rd Embodiment of this invention, a charging rate, various flags, the temperature of an SCR catalyst, and the temperature of a reducing agent injector. It is a time chart which shows the relationship between the vehicle speed in the control apparatus which concerns on 3rd Embodiment of this invention, a charging rate, various flags, the temperature of an SCR catalyst, and the temperature of a reducing agent injector. It is the flowchart which showed the routine which CPU of the control apparatus which concerns on 3rd Embodiment of this invention performs.

  Hereinafter, each embodiment (1st Embodiment-3rd Embodiment) of the control apparatus by this invention is described, referring drawings.

(First embodiment)
<Outline of device>
FIG. 1 shows a schematic configuration of a system in which a control device according to a first embodiment of the present invention (hereinafter also referred to as “first device”) is applied to an internal combustion engine 10. The internal combustion engine 10 is a four-cylinder diesel engine having four cylinders, a first cylinder to a fourth cylinder. Hereinafter, for convenience, the “internal combustion engine 10” is also simply referred to as “engine 10”.

  As shown in FIG. 1, the engine 10 includes an engine main body 20 including a fuel injection system, an intake system 30 for introducing air into the engine main body 20, and gas exhausted from the engine main body 20 to the outside of the engine 10. An exhaust system 40 for discharging, an electric power supply system 50 for supplying electric power to members constituting the engine 10, a supercharger 60 for compressing air that is driven by the energy of the exhaust and introduced into the engine body 20, and exhaust Is provided from the exhaust system 40 to the intake system 30, various sensors 81 to 89, and an electronic control unit 90.

  The engine body 20 includes a cylinder head 21 to which an intake system 30 and an exhaust system 40 are connected, and a plurality of fuel injection devices 22 provided on the cylinder head 21. The fuel injection device 22 is configured to inject fuel into the combustion chamber in response to an instruction signal from the electronic control device 90.

  The intake system 30 includes an intake port (not shown) formed in the cylinder head 21, an intake manifold 31 communicated with each cylinder via the intake port, and an intake pipe connected to a collective portion on the upstream side of the intake manifold 31. 32, a throttle valve (intake throttle valve) 33 that can change the opening area (opening cross-sectional area) in the intake pipe 32, a throttle valve actuator 33 a that rotationally drives the throttle valve 33, and an intake pipe upstream of the throttle valve 33 And an air cleaner 35 provided at the end of the intake pipe 32 upstream of the supercharger 60 provided upstream of the intercooler 34. The intake manifold 31 and the intake pipe 32 constitute an intake passage.

  The exhaust system 40 includes an exhaust port (not shown) formed in the cylinder head 21, an exhaust manifold 41 communicated with each cylinder via the exhaust port, and an exhaust pipe connected to a downstream gathering portion of the exhaust manifold 41. 42, an electric heater 43 provided downstream of the supercharger 60 provided in the exhaust pipe 42, an oxidation catalyst 44 provided downstream of the electric heater 43, and a diesel provided downstream of the oxidation catalyst 44 The particulate filter 45, the SCR catalyst 46 provided on the downstream side of the diesel particulate filter 45, and a reducing agent (for example, urea) in the exhaust gas introduced into the SCR catalyst 46 based on an instruction signal from the electronic control device 90. A reducing agent injector 47 for supplying water). The reducing agent injector 47 is connected to a reducing agent storage tank (not shown) through a pipe for transporting the reducing agent. Further, the reducing agent injector 47 includes an electric heater (not shown; hereinafter, also referred to as “reducing agent injector heater”). The electric heater 43, the oxidation catalyst 44, the diesel particulate filter 45, and the SCR catalyst 46 constitute a series of exhaust purification systems. Further, the exhaust manifold 41 and the exhaust pipe 42 constitute an exhaust passage.

  The power supply system 50 includes a battery 51 and a regeneration device 52 that can regenerate power when the vehicle on which the engine 10 is mounted decelerates. The regenerative device 52 is connected to the battery 51, the electric heater 43, and the reducing agent injector 47, and supplies regenerated electric power to any of them in response to an instruction signal from the electronic control device 90. It has become. Further, the battery 51 is connected to the electric heater 43 and the reducing agent injector 47, and supplies the regenerated electric power to any of them according to an instruction from the electronic control unit 90. Yes. Hereinafter, for convenience, the regenerated electric power is also referred to as “regenerative electric power”.

  The supercharger 60 includes a compressor 61 provided in the intake passage (intake pipe 32) and a turbine 62 provided in the exhaust passage (exhaust pipe 42). The supercharger 60 is configured to compress the air introduced into the compressor 61 (that is, the air introduced into the combustion chamber) using the energy of the exhaust gas introduced into the turbine 62.

  The EGR device 70 includes an exhaust recirculation pipe 71 that constitutes a passage (EGR passage) that recirculates exhaust gas from the exhaust manifold 41 to the intake manifold 31, an EGR gas cooling device (EGR cooler) 72 that is provided in the exhaust recirculation pipe 71, and And an EGR control valve 73 provided in the exhaust gas recirculation pipe 71. The EGR control valve 73 changes the amount of exhaust gas that is recirculated in accordance with an instruction signal from the electronic control unit 90.

  As various sensors 81 to 89, an air introduction amount sensor 81, an intake air temperature sensor 82, a supercharging pressure sensor 83, a crank position sensor 84, a NOx sensor 85, an exhaust gas temperature sensor 86, a catalyst temperature sensor 87, a reducing agent injector sensor 88, An accelerator opening sensor 89 is provided.

  The air introduction amount sensor 81 is provided in the intake passage (intake pipe 32). The air introduction amount sensor 81 outputs a signal corresponding to the mass flow rate of air flowing through the intake pipe 32 (that is, the mass of air sucked into the engine 10).

  The intake air temperature sensor 82 is provided in the intake passage (intake pipe 32). The intake air temperature sensor 82 outputs a signal corresponding to the intake air temperature that is the temperature of the air flowing through the intake pipe 32.

  The supercharging pressure sensor 83 is provided in the intake pipe 32 on the downstream side of the throttle valve 33. The supercharging pressure sensor 83 outputs a signal representing the pressure of the air in the intake pipe 32 (that is, the supercharging pressure provided by the supercharger 60).

  The crank position sensor 84 is provided in the vicinity of a crankshaft (not shown). The crank position sensor 84 outputs a signal corresponding to the rotation of the crankshaft (that is, a signal corresponding to the engine rotational speed).

  The NOx sensor 85 is provided at a position upstream of the SCR catalyst 46. The NOx sensor 85 outputs a signal corresponding to the concentration of nitrogen oxide (NOx) in the exhaust gas introduced into the SCR catalyst 46.

  The exhaust temperature sensor 86 is provided at a position upstream of the SCR catalyst 46. The exhaust gas temperature sensor 86 outputs a signal corresponding to the temperature of the exhaust gas introduced into the SCR catalyst 46.

  The catalyst temperature sensor 87 is provided in the SCR catalyst 46. The catalyst temperature sensor 87 outputs a signal corresponding to the temperature Tcat of the SCR catalyst 46.

  The reducing agent injector 88 is provided on the reducing agent injector 47. The reducing agent injector sensor 88 outputs a signal corresponding to the temperature Tinj of the reducing agent injector 47.

  The accelerator opening sensor 89 is provided on an accelerator pedal AP that is operated by an operator of the engine 10. The accelerator opening sensor 89 outputs a signal corresponding to the opening of the accelerator pedal AP.

  The electronic control unit 90 includes a CPU 91, a ROM 92 in which programs executed by the CPU 91, tables (maps), constants, and the like are stored in advance, a RAM 93 in which the CPU 91 temporarily stores data as necessary, and data when the power is turned on. And a backup RAM 94 that holds the stored data even while the power is cut off, and an interface 95 including an AD converter. The CPU 91, ROM 92, RAM 93, RAM 94, and interface 95 are connected to each other via a bus.

  The interface 95 is connected to the various sensors described above, and transmits a signal output from them to the CPU 91. Further, the interface 95 is connected to the fuel injection device 22, the actuator 33a, the reducing agent injector 47, the battery 51, the regenerative device 52, the EGR control valve 63, and the like, and sends an instruction signal to them in response to an instruction from the CPU 91. It has become.

<Concept of control>
Hereinafter, the concept of control in the first device applied to the engine 10 will be described with reference to FIG. FIG. 2 is a “schematic flowchart” showing an outline of the operation of the first device.

  In step 210 of FIG. 2, the first device determines whether electric power is currently being regenerated (for example, a vehicle on which the engine 10 is mounted is being decelerated). If the power is currently being regenerated, the first device determines “Yes” in step 210 and proceeds to step 220.

  In step 220, the first device determines whether or not the regenerative power should be supplied to the exhaust gas purification means (specifically, the electric heater 43). If the regenerative power should not be supplied to the exhaust gas purification means at the present time, the first device determines “No” in step 220 and proceeds to step 230. In step 230, the first device charges the power storage means (specifically, battery 51) with regenerative power.

  On the other hand, if regenerative power should be supplied to the exhaust gas purification means (electric heater 43) at the present time, the first device determines “Yes” in step 220 and proceeds to step 240. In step 240, the first device determines whether or not a condition is satisfied that the temperature of the catalyst (specifically, the SCR catalyst 46) is equal to or higher than a predetermined threshold temperature (for details of this condition). , Described later).

  If the above condition is satisfied at the present time, the first device determines “Yes” in step 240 and proceeds to step 250. In step 250, the first device prohibits the supply of regenerative power to the exhaust gas purification means (electric heater 43).

  On the other hand, if the above condition is not satisfied at the present time, the first device makes a “No” determination at step 240 to proceed to step 260. In step 260, the CPU 91 supplies regenerative power to the exhaust gas purification means (electric heater 43).

If the first device is not currently regenerating power, the first device determines “No” in step 210 and proceeds to step 295. In this case, neither the regenerative power is charged to the power storage means (battery 51) nor the regenerative power is supplied to the exhaust gas purification means (electric heater 43).
The above is the description of the first device.

(Second Embodiment)
Next, as an example in which the concept of control shown in the first device is actually applied to the engine 10, “when regenerative power is prohibited from being supplied to the exhaust gas purification means (electric heater 43), Is supplied to the reducing agent supply means (reducing agent injector 47). " Hereinafter, the control device in this embodiment is also referred to as a “second device”.

<Example of control by second device>
Hereinafter, an example of control in the second device will be described with reference to FIG. FIG. 3 is a time chart showing an example in which control in the second device is performed. In FIG. 3, a waveform in which the actual waveform of each value is schematically shown is shown for easy understanding.

  At time t1 in the time chart shown in FIG. 3, as shown in the time chart (a), the speed Vc of the vehicle equipped with the engine 10 is the speed Vc1. At this time, as shown in the time chart (b), the charging rate SOC of the battery 51 is the charging rate SOC1. Further, as shown in the time chart (e), the temperature Tcat of the SCR catalyst 46 is the temperature Tcat1.

  Thereafter, at time t2, deceleration of the vehicle is started. Therefore, the vehicle speed Vc starts to decrease after time t2. At this time, power is regenerated by the regenerative device 52, and regenerative power is supplied to the battery 51. As a result, the charging rate SOC of the battery 51 gradually increases after time t2. At time t3, the charging rate SOC of the battery 51 reaches a predetermined threshold value SOCth.

  When the charging rate SOC of the battery 51 reaches the threshold SOCth, as shown in the time chart (c), the value of the electric heater operation flag XHEAT indicating whether to supply regenerative power to the electric heater 43 is changed from “0” to “ 1 ". The electric heater operation flag XHEAT indicates that regenerative power is supplied to the electric heater 43 when the value is “1”, and the regenerative power to the electric heater 43 when the value is “0”. (The details of the electric heater operation flag XHEAT will be described later). As a result, regenerative power starts to be supplied to the electric heater 43 at time t3.

  When regenerative power is supplied to the electric heater 43, the temperature of the exhaust gas passing through the electric heater 43 rises. Then, the exhaust gas is introduced into the SCR catalyst 46 provided at a position downstream of the electric heater 43, so that the temperature Tcat of the SCR catalyst 46 also increases. Therefore, after time t3, the temperature Tcat of the SCR catalyst 46 gradually increases.

  It should be noted that the exhaust gas having a certain high temperature is introduced into the SCR catalyst 46 at a time before time t3 (at the time when regenerative power starts to be supplied to the electric heater 43). Therefore, in practice, it is considered that the temperature Tcat of the SCR catalyst 46 has increased even at a time before time t3. However, in this description, it is assumed that the temperature Tcat of the SCR catalyst 46 does not change (is a fixed value) at a time point before the time t3 for easy understanding.

  In addition, it takes a predetermined length of time from when the regenerative power starts to be supplied to the electric heater 43 until the exhaust gas whose temperature has risen is introduced into the SCR catalyst 46. Therefore, in reality, it is considered that the temperature Tcat of the SCR catalyst 46 starts to rise at the time after the predetermined time length has elapsed from time t3. However, in this description, it is assumed that the temperature Tcat of the SCR catalyst 46 starts to increase at the time t3 so as to facilitate understanding.

  Then, at time t4 after a predetermined time length has elapsed from time t3, the temperature Tcat of the SCR catalyst 46 reaches a predetermined threshold value Tcatth. When the temperature Tcat of the SCR catalyst 46 reaches the threshold value Tcatth, the value of the electric heater operation flag XHEAT is changed from “1” to “0” and, as shown in the time chart (d), the reducing agent injector heater operation flag XINJ. Is changed from “0” to “1”. The reducing agent injector heater operation flag XINJ indicates that regenerative power is supplied to the reducing agent injector heater when the value is “1”, and the reducing agent injector heater when the value is “0”. Represents that no regenerative power is supplied (details of the reducing agent injector heater operation flag XINJ will be described later). As a result, at time t3, the supply of regenerative power to the electric heater 43 is prohibited (stopped), and the supply of regenerative power to the reducing agent injector heater is started.

  Thereafter, at time t5 when a predetermined time length has elapsed from time t4, the vehicle speed Vc reaches the speed Vc2, and the deceleration of the vehicle is terminated. At this time, the value of the reducing agent injector heater flag XINJ is changed from “1” to “0”, and the supply of regenerative power to the reducing agent injector heater is ended.

As described above, when the control in the second device of the present invention is performed, the regenerative power is supplied to the electric heater 43 when the regenerative power is to be supplied to the electric heater 43 (when the charging rate SOC of the battery 51 is equal to or higher than the threshold SOCth). When it is prohibited to supply to 43 (when the temperature Tcat of the SCR catalyst 46 is equal to or higher than the threshold value Tcatth), regenerative power is supplied to the reducing agent injector heater.
The above is an example of control by the second device.

<Actual operation>
Hereinafter, the actual operation of the second device will be described.

  In the second device, the CPU 91 is configured to repeatedly execute each routine shown in the flowcharts of FIGS. 4 and 5 at predetermined timings. In these routines, the CPU 91 uses the electric heater operation flag XHEAT, the reducing agent injector heater operation flag XINJ, and the charge flag XCHR.

  The electric heater operation flag XHEAT indicates that regenerative power is supplied to the electric heater 43 when the value thereof is “1”. On the other hand, the electric heater operation flag XHEAT indicates that the supply of regenerative power to the electric heater 43 is prohibited when the value thereof is “0”.

  When the value of the reducing agent injector heater operating flag XINJ is “1”, it indicates that regenerative power is supplied to the reducing agent injector heater. On the other hand, when the value of the reducing agent injector heater operation flag XINJ is “0”, it indicates that regenerative power is not supplied to the reducing agent injector heater.

  When the value of the charge flag XCHR is “1”, it indicates that the battery 51 is charged with regenerative power. On the other hand, when the value of the charge flag XCHR is “0”, it indicates that the battery 51 is not charged with regenerative power.

Hereinafter, each routine executed by the CPU 91 will be described.
First, it is assumed that all the values of the electric heater operation flag XHEAT, the reducing agent injector heater operation flag XINJ, and the charge flag XCHR are currently set to “0”.

  The CPU 91 repeatedly executes the “flag setting routine” shown in the flowchart of FIG. 4 at every predetermined timing (for example, every time the crank angle of an arbitrary cylinder matches a specific crank angle before the intake stroke). It is supposed to be. The CPU 91 sets values of the electric heater operation flag XHEAT, the reducing agent injector heater operation flag XINJ, and the charge flag XCHR based on the operating state of the engine 10 by this routine.

  More specifically, when the CPU 91 starts processing from step 400 in FIG. 4 at a predetermined timing, the CPU 91 proceeds to step 405. In step 405, the CPU 91 determines whether or not the change rate ΔVc per unit time of the vehicle speed Vc is a negative value at the present time (that is, whether or not the vehicle is decelerating and power is being regenerated). Is determined. The vehicle speed Vc can be acquired by a vehicle speed sensor (not shown) provided in the vehicle.

  If the current change rate ΔVc is a negative value, the CPU 91 determines “Yes” in step 405, and proceeds to step 410. In step 410, CPU 91 determines whether or not charging rate SOC of battery 51 is equal to or greater than a predetermined threshold SOCth.

  When the current charging rate SOC of the battery 51 is smaller than the threshold SOCth, the CPU 91 determines “No” in step 410 and proceeds to step 415. In step 415, the CPU 91 stores “1” as the value of the charge flag XCHR. Thereafter, the CPU 91 proceeds to step 495 to end the present routine tentatively.

  Further, the CPU 91 performs the “power supply routine” shown by the flowchart in FIG. 5 at every predetermined timing (for example, every time the crank angle of an arbitrary cylinder matches a specific crank angle before the intake stroke). It is designed to be executed repeatedly. With this routine, the CPU 91 supplies regenerative power to a target (battery 51, electric heater 43, or reducing agent injector 47) determined according to the operating state of the engine 10.

  More specifically, when the CPU 91 starts processing from step 500 in FIG. 5 at a predetermined timing, the CPU 91 proceeds to step 510. In step 510, the CPU 91 determines whether or not the current value of the charge flag XCHR is “1”. Since the current value of the charge flag XCHR is “1”, the CPU 91 determines “Yes” in step 510 and proceeds to step 520.

  In step 520, the CPU 91 gives an instruction to the regenerative device 52 to supply regenerative power to the battery 51. Thereafter, the CPU 91 proceeds to step 595 to end the present routine tentatively.

  Thus, when the charging rate SOC of the battery 51 is smaller than the threshold value SOCth, the battery 51 is charged with regenerative power. Thereafter, when a predetermined time length elapses, the charging rate SOC of the battery 51 reaches the threshold value SOCth. At this time, when the CPU 91 starts processing from step 400 of the routine of FIG. 4, it determines “Yes” in step 410 following step 405, and proceeds to step 420.

  In step 420, the CPU 91 stores “0” as the value of the charge flag XCHR. Then, the process proceeds to step 425.

  In step 425, the CPU 91 determines whether or not the temperature Tcat of the SCR catalyst 46 is equal to or higher than a threshold value Tcatth. When the current temperature Tcat of the SCR catalyst 46 is lower than the threshold value Tcatth, the CPU 91 determines “No” in step 425 and proceeds to step 430. In step 430, the CPU 91 stores “1” in the value of the electric heater operation flag XHEAT. Thereafter, the CPU 91 proceeds to step 495 to end the present routine tentatively.

  Furthermore, when starting the process from step 500 of the routine of FIG. 5, the CPU 91 determines “No” in step 510 because the current value of the charge flag XCHR is “0”, and proceeds to step 530.

  In step 530, the CPU 91 determines whether or not the value of the electric heater operation flag XHEAT is “1”. Since the current value of the electric heater operation flag XHEAT is “1”, the CPU 91 determines “Yes” in step 530 and proceeds to step 540.

  In step 540, the CPU 91 gives an instruction to the regenerative device 52 to supply regenerative power to the electric heater 43. Thereafter, the CPU 91 proceeds to step 595 to end the present routine tentatively.

  Thus, when the charging rate SOC of the battery 51 is equal to or higher than the threshold SOCth and the temperature Tcat of the SCR catalyst 46 is lower than the threshold Tcatth, the electric heater 43 is charged with regenerative power. Thereafter, when a predetermined time length elapses, the temperature Tcat of the SCR catalyst 46 reaches the threshold value Tcatth. At this time, when the CPU 91 starts processing from step 400 of the routine of FIG. 4, it proceeds to step 425 via step 405, step 410 and step 420. Then, the CPU 91 determines “Yes” in step 425 and proceeds to step 435.

  In step 435, the CPU 91 stores “1” as the value of the reducing agent injector heater operation flag XINJ. Thereafter, the CPU 91 proceeds to step 495 to end the present routine tentatively.

  Furthermore, when the CPU 91 starts the process from step 500 of the routine of FIG. 5, the current value of the charge flag XCHR is “0” and the value of the electric heater operation flag XHEAT is “0”. In step 530, “No” is determined, and the process proceeds to step 550.

  In step 550, the CPU 91 determines whether or not the value of the reducing agent injector heater operation flag XINJ is “1”. Since the current value of the reducing agent injector heater operation flag XINJ is “1”, the CPU 91 determines “Yes” in step 550 and proceeds to step 560.

  In step 560, the CPU 91 gives an instruction to the regenerative device 52 to supply regenerative power to the reducing agent injector heater. Thereafter, the CPU 91 proceeds to step 595 to end the present routine tentatively.

  As described above, when the charging rate SOC of the battery 51 is equal to or higher than the threshold SOCth and the temperature Tcat of the SCR catalyst 46 is equal to or higher than the threshold Tcatth, regenerative power is charged to the reducing agent injector heater. Thereafter, when the deceleration of the vehicle is completed, the value of the change rate ΔVc of the vehicle speed Vc becomes zero or more. At this time, when the CPU 91 starts processing from step 400 of the routine of FIG. 4, it determines “No” in step 405 and proceeds to step 440 to step 450.

  The CPU 91 stores “0” in the value of the charge flag XCHR in step 440, stores “0” in the value of the electric heater operation flag XHEAT in step 450, and in step 450, the reducing agent injector heater operation flag XINJ. “0” is stored in the value of. Thereafter, the CPU 91 proceeds to step 495 to end the present routine tentatively.

  Furthermore, when the CPU 91 starts processing from step 500 of the routine of FIG. 5, the current value of the charge flag XCHR is “0”, the value of the electric heater operation flag XHEAT is “0”, and the reducing agent Since the value of the injector heater operation flag XINJ is “0”, “No” is determined in Step 510, Step 530 and Step 550, and the process proceeds to Step 595. Then, the CPU 91 once ends this routine.

  Thus, when the change rate ΔVc of the vehicle speed Vc is not a negative value, the regenerative power is not supplied to the battery 51, the electric heater 43, and the reducing agent injector heater.

As described above, the second device selects a target (battery 51, electric heater 43, or reducing agent injector heater) to which regenerative power is supplied based on the charging rate SOC of the battery 51 and the temperature Tcat of the SCR catalyst 46. To do.
The above is the description of the second device.

(Third embodiment)
Next, as another example in which the control concept shown in the first device is actually applied to the engine 10, “when the flow of the reducing agent is small, the regenerative power has priority over the exhaust purification means (electric heater 43). In this embodiment, the reducing agent supply means (reducing agent injector 47) is supplied ". Hereinafter, the control device in this embodiment is also referred to as a “third device”.

<Example of control by third device>
Hereinafter, an example of control in the third device will be described with reference to FIGS. 6 and 7. 6 and 7 are time charts showing an example in which control in the third device is performed. 6 and 7 show waveforms in which the actual waveform of each value is schematically shown for easy understanding.

  FIG. 6 is a time chart showing an example in which the temperature Tinj of the reducing agent injector 47 at a time point (time t3) at which the supply of regenerative power to the electric heater 43 is to be started is equal to or higher than a predetermined threshold value Tinjth. On the other hand, FIG. 7 is a time chart showing an example in which the temperature Tinj of the reducing agent injector 47 at the same point (time t3) is lower than a predetermined threshold value Tinjth.

  First, the example shown in FIG. 6 will be described. The example shown in FIG. 6 differs from the example shown in FIG. 3 only in that a time chart (f) is added. Therefore, the description overlapping with the description in FIG. 3 is omitted as appropriate.

  In the time chart shown in FIG. 6, the charging rate SOC of the battery 51 reaches the threshold value SOCth at time t3. At this time, as shown in the time chart (f), the temperature Tinj of the reducing agent injector 47 is equal to or higher than the threshold value Tinjth.

  In this case, similarly to the example shown in FIG. 3, supply of regenerative power to the electric heater 43 is started at time t3, and supply of regenerative power to the reducing agent injector heater is started at time t4. That is, the regenerative electric power is supplied to the reducing agent injector heater after being supplied to the electric heater 43.

  On the other hand, in the example shown in FIG. 7, the temperature Tinj of the reducing agent injector 47 at time t3 is lower than the threshold value Tinjth. In this case, not the value of the electric heater operation flag XHEAT but the value of the reducing agent injector heater operation flag XINJ is changed from “0” to “1” at time t3. Thereby, supply of regenerative electric power to the reducing agent injector heater is started at time t3.

  Thereafter, the temperature Tinj of the reducing agent injector 47 reaches the threshold value Tinjth at time t4a when a predetermined time length has elapsed from time t4. At this time, the value of the reducing agent injector heater operation flag XINJ is changed from “1” to “0”, and the value of the electric heater operation flag XHEAT is changed from “0” to “1”. As a result, at time t4a, the supply of regenerative power to the reducing agent injector heater is terminated, and the supply of regenerative power to the electric heater 43 is started.

  Thereafter, at time t5a when a predetermined time length has elapsed from time t4a, the vehicle speed Vc reaches the speed Vc2, and the deceleration of the vehicle is terminated. At this time, the value of the electric heater operation flag XHEAT is changed from “1” to “0”, and the supply of the regenerative power to the electric heater 43 is ended.

Thus, when the control in the third device of the present invention is performed, the flowability of the reducing agent when regenerative power is to be supplied to the electric heater 43 (when the charging rate SOC of the battery 51 is equal to or higher than the threshold SOCth). Is less than a predetermined degree (if the temperature Tinj of the reducing agent injector 47 is equal to or lower than the threshold value Tinjth), the regenerative power is given priority to the electric heater 43 and supplied to the reducing agent injector heater. The
The above is an example of control by the third device.

<Actual operation>
Hereinafter, the actual operation of the third device will be described.
The third device is different from the second device only in that the CPU 91 executes the flowchart shown in FIG. 8 instead of the flowchart shown in FIG. Thus, hereinafter, each routine executed by the CPU 91 will be described with a focus on this difference.

  Similar to the second device, the CPU 91 repeatedly executes the routines shown in FIGS. 8 and 5 at predetermined timings. In these routines, the CPU 91 uses the same electric heater operation flag XHEAT, reducing agent injector heater operation flag XINJ, and charge flag XCHR as those in the second device.

Hereinafter, each routine executed by the CPU 91 will be described.
First, it is assumed that all the values of the electric heater operation flag XHEAT, the reducing agent injector heater operation flag XINJ, and the charge flag XCHR are currently set to “0”.

  The CPU 91 repeatedly executes the “flag setting routine” shown in the flowchart of FIG. 8 at every predetermined timing (for example, every time the crank angle of an arbitrary cylinder matches a specific crank angle before the intake stroke). It is supposed to be. The CPU 91 sets values of the electric heater operation flag XHEAT, the reducing agent injector heater operation flag XINJ, and the charge flag XCHR based on the operating state of the engine 10 by this routine.

  The routine shown in FIG. 8 differs from the routine shown in FIG. 4 only in that step 810 is added. Therefore, in FIG. 8, steps for performing the same processing as the steps shown in FIG. 4 are denoted by the same reference numerals as those given to such steps in FIG. Detailed description of these steps will be omitted as appropriate.

  When the CPU 91 starts processing from step 800 in FIG. 8 at a predetermined timing, when the rate of change ΔVc per unit time of the vehicle speed Vc at the current time is a negative value, “Yes” is determined in step 405. Then, the process proceeds to step 410.

  When the current charging rate SOC of the battery 51 is smaller than the threshold SOCth, the CPU 91 determines “No” in step 410 and proceeds to step 415. Then, the CPU 91 stores “1” as the value of the charge flag XCHR in step 415, proceeds to step 895, and once ends this routine. Thereafter, like the second device, the CPU 91 executes the routine of FIG. 5 and supplies regenerative power to the battery 51.

  On the other hand, when the charging rate SOC of the battery 51 is equal to or greater than the threshold SOCth, the CPU 91 determines “Yes” in step 410 and proceeds to step 425 via step 420. When the current temperature Tcat of the SCR catalyst 46 is smaller than the threshold value Tcatth, the CPU 91 determines “No” in step 425 and proceeds to step 810.

  In step 810, the CPU 91 determines whether or not the temperature Tinj of the reducing agent injector 47 is equal to or lower than a predetermined threshold value Tinjth. If the current temperature Tinj of the reducing agent injector 47 is equal to or lower than the threshold value Tinjth, the CPU 91 determines “Yes” in step 810 and stores “1” in the value of the reducing agent injector heater operation flag XINJ in step 435. Then, the process proceeds to step 895 to end this routine once. Thereafter, like the second device, the CPU 91 executes the routine of FIG. 5 to supply regenerative power to the reducing agent injector heater.

  On the other hand, if the current temperature Tinj of the reducing agent injector 47 is higher than the threshold value Tinjth, the CPU 91 determines “No” in step 810 and sets “1” to the value of the electric heater operation flag XHEAT in step 430. , And the routine proceeds to step 895 to end the present routine tentatively. Thereafter, like the second device, the CPU 91 executes the routine of FIG. 5 and supplies regenerative power to the electric heater 43.

  Thus, even when the charging rate SOC of the battery 51 is equal to or higher than the threshold SOCth and the temperature Tcat of the SCR catalyst 46 is lower than the threshold Tcatth, if the temperature Tinj of the reducing agent injector 47 is equal to or lower than the threshold Tinjth, Prior to the electric heater 43, regenerative power is supplied to the reducing agent injector heater. Then, when the temperature Tinj of the reducing agent injector 47 becomes higher than the threshold value Tinjth, regenerative power is supplied to the electric heater 43.

As described above, the third device is based on the charging rate SOC of the battery 51, the temperature Tcat of the SCR catalyst 46, and the temperature Tinj of the reducing agent injector 47 (battery 51, electric heater 43). Alternatively, a reducing agent injector heater) is selected.
The above is the description of the third device.

<Summary of Embodiment>
As described with reference to FIGS. 1 to 8, the control device (first device to third device) according to the embodiment of the present invention is:
It is an exhaust purification means having a catalyst (SCR catalyst 46) for purifying exhaust discharged from the combustion chamber of the internal combustion engine 10, and it is possible to adjust the temperature Tcat of the catalyst 46 in accordance with the magnitude of the supplied electric power. Exhaust gas purification means (an exhaust gas purification system including the electric heater 43 and the SCR catalyst 46, etc., hereinafter referred to as 43 as a typical symbol),
Power storage means 51 capable of supplying electric power to the exhaust purification means;
Power regeneration that can regenerate electric power according to the operating state of the internal combustion engine 10 and that can supply the regenerated electric power to at least one of the exhaust gas purification means 43 and the power storage means 51. Means 52.

And the control device concerning the embodiment of the present invention,
Even when the regenerated electric power is to be supplied to the exhaust gas purification means 43 (eg, when “Yes” is determined in step 220 in FIG. 2), the temperature Tcat of the catalyst 46 is a predetermined threshold value. If the condition that the temperature is equal to or higher than the temperature Tcatth is satisfied (if it is determined “Yes” in step 240 in FIG. 2), the regenerated electric power may be supplied to the exhaust purification unit 43. It is forbidden (step 250 in FIG. 2).

Furthermore, the control device according to the embodiment of the present invention includes:
The catalyst 46 is a catalyst 46 that purifies the exhaust gas by reducing nitrogen oxides contained in the exhaust gas,
A reducing agent supply means (reducing agent injector 47) for supplying a reducing agent (urea water) into the exhaust gas introduced into the catalyst 46, and adjusts the temperature of the reducing agent according to the magnitude of the supplied electric power. A reducing agent supply means 47 having a configuration (reducing agent injector heater) capable of
When the regenerated power is prohibited from being supplied to the exhaust gas purification means 43 (when it is determined “Yes” in step 425 in FIG. 4), the regenerated power is supplied to the reducing agent supply means. It is configured to be supplied to.

In addition, the control device according to the embodiment of the present invention includes:
In the case where the regenerated electric power is to be supplied to the exhaust gas purification means 43 (in the case where “Yes” is determined in Step 410 in FIG. 8 and “No” is determined in Step 425), the reducing agent If the condition that the fluidity is smaller than the predetermined degree is satisfied (if “Yes” is determined in Step 810 of FIG. 8), the regenerated electric power has priority over the exhaust purification unit 43. Then, it is configured to be supplied to the reducing agent supply means 47.

  The present invention is not limited to the above embodiments, and various modifications can be adopted within the scope of the present invention.

  For example, the concept of the control device applied to “one embodiment” of the plurality of embodiments (first embodiment to third embodiment) is changed to “other implementations” of the plurality of embodiments. The idea of the control device in “one or more forms” can be applied. In other words, one embodiment of the plurality of embodiments may be combined with one or more other embodiments.

  Further, for example, in the second device, it is determined with reference to the temperature Tcat of the SCR catalyst 46 whether the regenerative power is supplied to the electric heater 43 or the reducing agent injector heater. However, this determination may be made with reference to the temperature of the oxidation catalyst 44.

  Specifically, the oxidation catalyst 44 converts nitrogen monoxide in the exhaust gas into nitrogen dioxide at a predetermined conversion rate depending on the temperature. Therefore, if the temperature of the oxidation catalyst 44 is appropriately adjusted according to the operating state of the engine 10, the composition of nitrogen oxides contained in the exhaust gas introduced into the SCR catalyst 46 after passing through the oxidation catalyst 44 is “SCR catalyst. Can be adjusted to a composition capable of efficiently removing (reducing) nitrogen oxides (for example, a ratio of nitric oxide to nitrogen dioxide is 1: 1). Therefore, in the second device, the above determination is made with reference to the temperature of the oxidation catalyst 44, whereby the nitrogen oxides in the exhaust are efficiently removed. That is, the emission emission amount is reduced as much as possible.

  In addition, for example, in the third device, it is determined with reference to the temperature Tinj of the reducing agent injector 47 whether the regenerative power is supplied first to the electric heater 43 or the reducing agent injector heater. However, this determination may be made with reference to the temperature of the reducing agent itself.

  Furthermore, in the above embodiments, members (for example, the electric heater 43 and the oxidation catalyst 44) constituting the exhaust gas purification means (exhaust gas purification system) are arranged in the exhaust passage in a state where they are separated from each other independently. (See, for example, FIG. 2). However, these members do not necessarily have to be arranged as such, and may be arranged in the exhaust passage in a state of being connected to each other (integrated state).

  As described above, the present invention can be used as a control device applied to an internal combustion engine having a configuration capable of regenerating electric power according to the operating state of the internal combustion engine.

  DESCRIPTION OF SYMBOLS 10 ... Internal combustion engine, 43 ... Electric heater, 44 ... Oxidation catalyst, 45 ... Diesel particulate filter, 46 ... SCR catalyst, 47 ... Reducing agent injector, 51 ... Battery, 52 ... Regenerative device, 90 ... Electronic control device

Claims (3)

An exhaust gas purification unit having a catalyst for purifying exhaust gas discharged from a combustion chamber of an internal combustion engine, the exhaust gas purification unit having a configuration capable of adjusting the temperature of the catalyst according to the magnitude of electric power supplied; ,
Power storage means capable of supplying power to the exhaust purification means;
Electric power regeneration means capable of regenerating electric power according to the operating state of the internal combustion engine and capable of supplying the regenerated electric power to at least one of the exhaust gas purification means and the power storage means;
With
Even if the regenerated electric power is to be supplied to the exhaust gas purification means, the regenerated electric power can be reduced if the condition that the temperature of the catalyst is equal to or higher than a predetermined threshold temperature is satisfied. A control device for an internal combustion engine configured to be prohibited from being supplied to the exhaust gas purification means. The control device according to claim 1,
The catalyst is a catalyst that purifies the exhaust gas by reducing nitrogen oxides contained in the exhaust gas;
A reducing agent supply means for supplying a reducing agent into the exhaust gas introduced into the catalyst, the reducing agent supply means having a configuration capable of adjusting the temperature of the reducing agent according to the magnitude of the supplied electric power. With
A control device for an internal combustion engine configured to supply the regenerated electric power to the reducing agent supply means when the regenerated electric power is prohibited from being supplied to the exhaust gas purification means. The control device according to claim 2,
In the case where the regenerated electric power is to be supplied to the exhaust gas purification unit, the regenerated electric power is converted into the exhaust gas purification if the condition that the fluidity of the reducing agent is smaller than a predetermined degree is satisfied. A control device for an internal combustion engine configured to be supplied to the reducing agent supply means in preference to the means.

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