JP2009083541A - Controller for hybrid vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To suitably maintain active state of the catalyst, for example, in preparation for the operation of an internal combustion engine, to suppress power consumption required for the maintenance, and further, to secure opportunity of purge processing. <P>SOLUTION: A hybrid vehicle controller includes a heating means for heating a catalyst, according to an energizing amount, the catalyst provided in a pipe passage in an exhaust pipe to purify exhaust gas exhausted by combustion in an internal combustion engine; an exhaust purge means for introducing evaporated fuel in a fuel tank storing fuel, as a purge gas from a canister that adsorbs the evaporated fuel to the upstream side of the catalyst in the exhaust pipe; an adjusting means for adjusting the introduced amount of the purge gas by the exhaust purge means; and a temperature-specifying means for specifying the temperature of the catalyst. The hybrid vehicle controller, further, includes a control means for controlling the energizing amount to the heating means and the driving state of the adjusting means, based on at least the specified temperature of the catalyst and the traveling state of the hybrid vehicle. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a control device for a hybrid vehicle having a catalyst for exhaust gas purification.

  This type of catalyst exhibits the ability to purify exhaust gas in an active state heated to an appropriate activation temperature. Here, in the hybrid vehicle, only the electric motor may be used as a drive source of the vehicle, and the operation time of the internal combustion engine is relatively short. When the internal combustion engine is not operating, the catalyst temperature tends to decrease. On the other hand, the operation time of the internal combustion engine is often unpredictable. Then, in order to ensure the emission characteristics, it is preferable to keep the catalyst in an active state in advance, that is, to perform preheating even when the internal combustion engine is not operating.

  In paragraph 0016 of the patent document 1, in a hybrid vehicle, when the evaporated fuel stored in the canister reaches a predetermined amount during traveling by the motor, the evaporated fuel is taken out by a combustion means provided separately from the internal combustion engine. There has been proposed a technique for burning and activating the catalyst with the heat of combustion. However, in this configuration, the main issue is to appropriately control the evaporated fuel stored in the canister by appropriately burning the evaporated fuel by the combustion means, and there are almost no specific details on how to adjust the catalyst temperature. Not disclosed. Therefore, it is not always possible to raise the catalyst temperature to the activation temperature. In particular, when the internal combustion engine is started, the catalyst temperature is low, and the catalyst may remain in an inactive state. In addition, since the combustion means is provided separately from the internal combustion engine, the structure may be complicated.

  In the paragraph 0045 of the patent document 2, after the internal combustion engine is started, the catalyst temperature is raised to the activation temperature early by the electrically heated catalyst, and the HC in the exhaust gas and the HC in the vaporized gas from the fuel tank are efficiently used. Techniques for purifying well have been proposed. However, simply heating with an electrically heated catalyst is not preferable in terms of power consumption.

  In the paragraph 0037 of Patent Document 3, during the fuel cut, the purge of the evaporated fuel is performed within a range in which the catalyst does not shift to an inactive state and the internal pressure of the canister does not become excessively high. Techniques to do this are disclosed. At this time, if it is predicted that the catalyst shifts to the inactive state based on the active state characteristic value, the execution of the exhaust purge is prohibited, so that the emission characteristic is prevented from deteriorating with the execution of the exhaust purge. That's it. However, it is not assumed that the catalyst can be shifted to an active state at an arbitrary timing, such as a current heating type catalyst. If so, exhaust purge may be prohibited more than necessary, which is not preferable for a hybrid vehicle that is short of purge processing.

JP 2006-177323 A JP-A-10-121949 JP 2004-76673 A

  The present invention has been made in view of, for example, the above-described problems, and is capable of maintaining the catalyst in an active state in advance in preparation for the operation of the internal combustion engine of the hybrid vehicle, and suppressing power consumption required therefor, It is another object of the present invention to provide a control apparatus for a hybrid vehicle that can secure an opportunity for purge processing.

  In order to solve the above-described problems, a control apparatus for a hybrid vehicle according to the present invention generates an electric power by using an internal combustion engine that generates power by burning fuel and at least a part of the generated power, and is obtained by the power generation. A control device for a hybrid vehicle comprising a generator that charges a battery with generated electric power and an electric motor that outputs motive power corresponding to discharge power discharged from the battery, and is discharged along with combustion in the internal combustion engine Heating means for heating the catalyst provided in the exhaust pipe line for purifying the exhaust gas in accordance with the amount of current supplied to the heating means, and evaporating fuel in the fuel tank for storing the fuel, From the canister that adsorbs fuel to the upstream side of the catalyst in the exhaust pipe, there is an exhaust purge means that introduces as purge gas, and a par by the exhaust purge means. An adjusting means for adjusting the amount of gas introduced, a temperature specifying means for specifying the temperature of the catalyst, an energization amount to the heating means based on at least the temperature of the specified catalyst and the running state of the hybrid vehicle And control means for controlling the driving state of the adjusting means.

  According to the hybrid vehicle control apparatus of the present invention, first, in the hybrid vehicle that preferably performs preheating, the catalyst provided in the pipe of the exhaust pipe can be appropriately heated and activated by the heating means. At this time, since the control means controls the energization amount to the heating means and the driving state of the adjusting means based at least on the temperature of the specified catalyst and the operating status of the internal combustion engine, the internal combustion engine is not operating. However, it is not always necessary to energize the heating means. For example, when the temperature of the catalyst exceeds the activation temperature (that is, the temperature at which the catalyst is activated and the exhaust gas purification capability can be suitably exerted, or a temperature with a slight margin), the purge gas is used as the catalyst. If introduced, the evaporated fuel burns in the catalyst, so that the temperature of the catalyst can be maintained even when the energization of the heating means is stopped. The evaporated fuel combusted at this time is not necessarily wasted. In view of the limit of the amount of adsorption, the canister that adsorbs the evaporated fuel needs to be appropriately combusted by such a purge process. Therefore, while maintaining the catalyst in an active state, the power consumption required for the catalyst can be suppressed, and the opportunity for the purge treatment can be suitably secured, which is very convenient in practice.

  More specifically, the hybrid vehicle to be controlled includes an internal combustion engine, a generator, and an electric motor. An internal combustion engine generates power by burning fuel such as gasoline or alcohol fuel. The generator uses, for example, a regenerative brake to generate electric power using at least a part of the power generated by the internal combustion engine, and charges the battery with electric power obtained by the electric power generation. The electric motor is a so-called motor, and outputs motive power according to the discharge power discharged from the battery.

  The heating means is, for example, an electric heating type (Electrical Heating: EH) or an induction heating type (Induction Heating: IH), etc. Depending on the heating. This catalyst is, for example, a three-way catalyst, and its exhaust gas purification capacity depends on temperature. Therefore, it is desirable for the heating means to be able to heat the catalyst to at least the activation temperature (for example, 350 ° C.) of the catalyst. Note that “heating according to the amount of energization” means that the amount of energization to the heating means and the amount of heating have a predetermined relationship such as a positive correlation, and the heating amount by the control means as described later. Means that it can be controlled in at least two stages.

  The exhaust purge means is composed of, for example, a canister for adsorbing evaporated fuel in a fuel tank of an internal combustion engine and a tubular member communicating with the upstream side of the catalyst of the exhaust pipe, and the evaporated fuel is sent upstream of the catalyst of the exhaust pipe. And introduced as a purge gas. Note that “upstream side of the catalyst in the exhaust pipe” means that the purge gas introduced into the exhaust pipe passes through the catalyst and is discharged outside the vehicle. Further, in addition to the exhaust purge means, an intake purge means for introducing purge gas into the intake pipe may be further provided.

  The adjusting means is, for example, a turbine pump provided in a pipe line of the exhaust purge means, and adjusts the amount of purge gas introduced by the exhaust purge means. For example, when the adjusting means is driven, purge gas is introduced by the exhaust purge means, and when the adjusting means is not driven (that is, stopped), purge gas is not introduced by the exhaust purge means. Alternatively, when the adjusting means is driven, the amount of purge gas introduced by the exhaust purge means is adjusted in at least two stages according to the driving force.

  The control means is, for example, an electronic control unit (ECU), and is based on at least the temperature of the catalyst specified as described above and the running state of the hybrid vehicle, and the adjustment means. To control the driving state. Here, the “driving state of the hybrid vehicle” means whether a start request is made by the driver to the hybrid vehicle, whether the hybrid vehicle is running, or whether each of the internal combustion engine and the electric motor is operating. Indicates the state. In particular, when there is a start request from the driver for the hybrid vehicle, even if the internal combustion engine is initially stopped, the internal combustion engine will eventually be operated, so preheating is required in preparation. Therefore, the control means monitors not only the temperature of the catalyst specified as described above, but also the running state of the hybrid vehicle, and if necessary, the energization amount to the heating means so as to maintain the active state of the catalyst, And the drive state of the adjustment means is controlled. As a result, the catalyst is heated by the heating means, and purge gas is introduced into the catalyst in addition to or instead of this.

  Therefore, while maintaining the catalyst in an active state, the power consumption required for the catalyst can be suppressed, and the opportunity for the purge treatment can be suitably secured, which is very convenient in practice.

  In one aspect of the control apparatus for a hybrid vehicle according to the present invention, the control means energizes the heating means before the start request of the internal combustion engine, and the temperature of the specified catalyst exceeds a predetermined activation temperature. Stops the energization of the heating means and drives the adjusting means so as to introduce the purge gas into the exhaust pipe.

  According to this aspect, the control means first energizes the heating means before the start request of the internal combustion engine. After that, when the temperature of the identified catalyst exceeds a predetermined activation temperature (that is, a temperature at which the catalyst is activated and exhaust gas purification ability can be suitably exhibited, or a temperature with a slight margin). Assuming that the preheating is sufficiently performed, the energization to the heating means is stopped. Here, “beyond the activation temperature” includes the meaning of “above the activation temperature” or “higher than the activation temperature”. At the same time as or after the stop of energization, the control means drives the adjustment means so as to introduce the purge gas into the exhaust pipe. Therefore, even if the energization is stopped, the purge gas burns in the catalyst, so that the temperature of the catalyst can be suitably maintained. If the temperature of the catalyst exceeds the combustion temperature of the evaporated fuel, the purge gas may be introduced even if it does not exceed the activation temperature.

  In this aspect, the apparatus further comprises concentration specifying means for specifying the concentration of the evaporated fuel in the purge gas, and the control means is configured to adjust the adjusting means when the specified concentration of the evaporated fuel falls below a predetermined concentration threshold. The driving may be stopped.

  According to this aspect, the concentration specifying means is, for example, an air-fuel ratio sensor provided in the exhaust purge means or in the canister, and specifies the concentration (for example, volume concentration or hydrocarbon concentration) of the evaporated fuel in the purge gas. The concentration of the evaporated fuel specified in this way is a predetermined concentration threshold (that is, the lower limit value of the evaporated fuel concentration that can burn and contribute to the maintenance of the catalyst temperature when purge gas is introduced into the catalyst. If the value is below the predetermined value), the control means stops driving the adjusting means, assuming that the purge process has been completed. Therefore, it is possible to avoid introducing a purge gas into the catalyst that may cause a decrease in the catalyst temperature.

  Alternatively, in this aspect, the control unit is configured so that the temperature of the specified catalyst is maintained at a predetermined activation temperature after the energization of the heating unit is stopped until the start request of the internal combustion engine. You may make it control the drive state of an adjustment means.

  According to this aspect, it is desirable that the catalyst is activated when the internal combustion engine is next requested even after the energization of the heating means is stopped. On the other hand, it is difficult to predict when there is a request for starting the internal combustion engine. However, it is not preferable in terms of power consumption to continue energizing the heating means. Therefore, the control means controls the drive state of the adjustment means so that the temperature of the specified catalyst is maintained at a predetermined activation temperature after the energization of the heating means is stopped until the start request of the internal combustion engine is reached. That is, during this period, the control means controls the drive state of the adjustment means in a feedback manner based on the temperature of the catalyst. For example, when the temperature of the catalyst rises to some extent, the driving of the adjusting means is stopped, and then the adjusting means is driven again when the temperature of the catalyst decreases. Therefore, the catalyst can be maintained in an activated state in preparation for the next request for starting the internal combustion engine while suppressing power consumption by the heating means.

  In the aspect controlled in this way, the control means resumes energization to the heating means when the temperature of the specified catalyst falls below the predetermined activation temperature after stopping energization to the heating means. You may make it do.

  According to this aspect, after the energization of the heating means is stopped, when the temperature of the specified catalyst is lower than the predetermined activation temperature, it is necessary to immediately increase the temperature of the catalyst in preparation for the start request for the internal combustion engine. There is. However, it takes a relatively long time to raise the temperature of the catalyst only by controlling the driving state of the adjusting means. In particular, if the temperature of the catalyst falls below the combustion temperature of the evaporated fuel, the temperature of the catalyst cannot be increased only by controlling the driving state of the adjusting means. Therefore, in such a case, the control means resumes energization to the heating means. Therefore, the temperature of the catalyst can be quickly recovered to the activation temperature.

  In another aspect of the control apparatus for a hybrid vehicle according to the present invention, the hybrid vehicle control apparatus may further include an air introduction means for mixing the air with the purge gas introduced by the exhaust purge means.

  According to this aspect, when the concentration of the evaporated fuel in the purge gas introduced by the exhaust purge means is too high to be processed by the catalyst, a predetermined amount of the atmosphere is purged by the atmosphere introduction means communicating with the atmosphere. To mix. Therefore, deterioration of exhaust emission can be avoided.

  In another aspect of the hybrid vehicle control device according to the present invention, the hybrid vehicle may start the internal combustion engine in response to a high load request even if the remaining charge of the battery is sufficient.

  According to this aspect, the hybrid vehicle to be controlled is a so-called Blended type plug-in hybrid vehicle, and starts the internal combustion engine in response to a high load request even if the remaining charge amount of the battery is sufficient. Then, it is difficult to predict when there is a request for starting the internal combustion engine. Therefore, the advantages of the various aspects described above become more prominent.

  The operation and other advantages of the present invention will become apparent from the best mode for carrying out the invention described below.

  Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings as the best mode for carrying out the invention.

  First, a schematic configuration of a hybrid vehicle 1 according to an embodiment of the present invention will be described with reference to FIG. Here, FIG. 1 is a schematic top view showing the hybrid vehicle 1 according to the embodiment of the present invention.

  In FIG. 1, a hybrid vehicle 1 is a blended plug-in hybrid vehicle that activates an internal combustion engine when, for example, the remaining battery level is sufficient but a high load is required. The hybrid vehicle 1 includes front wheels 20R and 20L, rear wheels 22R and 22L, an internal combustion engine 40, a planetary gear PG, a differential gear DG, and gears 4 and 6. Hybrid vehicle 1 further includes a battery B, a boosting unit 20 that boosts DC power output from battery B, and an inverter 14 that exchanges DC power with boosting unit 20. Hybrid vehicle 1 further includes a motor generator MG1 that generates electric power by receiving power from internal combustion engine 40 via planetary gear PG, and a motor generator MG2 whose rotation shaft is connected to planetary gear PG. Hereinafter, a specific configuration of each part will be described.

  Planetary gear PG includes a sun gear, a ring gear, a pinion gear that meshes with both the sun gear and the ring gear, and a planetary carrier that rotatably supports the pinion gear around the sun gear. Planetary gear PG has first to third rotation shafts. The first rotating shaft is a rotating shaft of a planetary carrier connected to the internal combustion engine 40. The second rotating shaft is a rotating shaft of a sun gear connected to motor generator MG1. The third rotating shaft is a rotating shaft of a ring gear connected to motor generator MG2. A gear 4 is attached to the third rotating shaft, and the gear 4 drives the gear 6 to transmit mechanical power to the differential gear DG. The differential gear DG transmits the mechanical power received from the gear 6 to the front wheels 20R and 20L, and transmits the rotational force of the front wheels 20R and 20L to the third rotation shaft of the planetary gear PG via the gears 6 and 4. Planetary gear PG plays a role of dividing power between internal combustion engine 40 and motor generators MG1, MG2. That is, the planetary gear PG determines the rotation of the remaining one rotation shaft in accordance with the rotation of the two rotation shafts among the three rotation shafts. Therefore, while operating the internal combustion engine 40 in a relatively efficient region, the motor generator MG2 is driven by controlling the power generation amount of the motor generator MG1 to control the vehicle speed, thereby realizing an overall energy efficient vehicle. is doing.

  The battery B is made of a secondary battery such as nickel hydride or lithium ion, for example, and supplies DC power to the boosting unit 20 and is charged by DC power from the boosting unit 20. The boosting unit 20 boosts the DC power from the battery B and supplies the boosted DC power to the inverter 14. Battery B includes a plurality of battery units B0 to Bn connected in series as an assembled battery. System main relays SR1 and SR2 are provided between boost unit 20 and battery B, and a high voltage is cut off when the vehicle is not in operation.

  When the internal combustion engine 40 is started, the inverter 14 converts the supplied DC power into AC power and controls the motor generator MG1. After starting internal combustion engine 40, inverter 14 converts AC power generated by motor generator MG1 into DC power. The voltage of the DC power is converted into an appropriate voltage by the boost unit 20 to charge the battery B. Inverter 14 further drives and controls motor generator MG2.

  Motor generator MG2 assists internal combustion engine 40 to drive front wheels 20R and 20L during driving. On the other hand, at the time of braking, motor generator MG2 performs a regenerative operation and converts the rotational energy of the wheels into electric energy. The obtained electric energy is charged into the battery B via the inverter 14 and the booster unit 20.

  The hybrid vehicle 1 further includes an accelerator sensor 9 that is an input part of an acceleration request instruction from the driver and detects the position of the accelerator pedal, a voltage sensor 10 attached to the battery B, and an accelerator opening Acc from the accelerator sensor 9. And a control device 30 that controls the internal combustion engine 40, the inverter 14, and the booster unit 20 in accordance with the voltage VB from the voltage sensor 10. The voltage sensor 10 detects the voltage VB of the battery B and transmits it to the control device 30.

  The hybrid vehicle 1 further includes a socket 16 for connecting a plug 104 provided at the end of a charging cable 102 extending from the external charging device 100 and a coupling confirmation for recognizing that the plug 104 is connected to the socket 16. Sensor 18 and charging inverter 12 that receives AC power from external charging device 100 via socket 16 are further included. The charging inverter 12 is connected to the battery B, and supplies charging DC power to the battery B. For example, a sensor that detects a magnet on the plug side, a button type that is pushed in when the plug is inserted, or a sensor that detects the connection resistance of the energization path is used as the coupling confirmation sensor 18.

  In FIG. 1, the plug-in type hybrid vehicle 1 has been described. However, the internal combustion engine is a hybrid vehicle that operates regularly or irregularly. If it is necessary to activate the catalyst each time, the plug-in type hybrid vehicle 1 is used. It does not have to be.

  Next, a more detailed configuration of the internal combustion engine 40 will be described with reference to FIG. Here, FIG. 2 is a schematic cross-sectional view showing the internal combustion engine 40 according to the embodiment.

  In FIG. 2, the intake pipe 206 communicates the cylinder 201 and the outside air, and is configured to be able to suck air into the cylinder 201 of the internal combustion engine 40. In the pipe of the intake pipe 206, a cleaner that purifies the intake air, an air flow meter that detects the mass flow rate of the intake air (that is, the intake air amount), an intake air temperature sensor that detects the temperature of the intake air, A throttle valve that adjusts the intake air amount, a throttle position sensor that detects the opening of the throttle valve, and a throttle valve motor that drives the throttle valve based on the amount of depression of the accelerator pedal by the driver are provided. Further downstream, a surge tank 2061 that stores intake air and distributes it to each of the plurality of cylinders, a pressure sensor 2062 that detects an intake pipe pressure in the surge tank 2061, and a fuel injection valve 207 are provided. The fuel injection valve 207 injects the fuel supplied from the fuel tank 223 into the intake pipe 206 according to the control of the control device 30. The injected fuel is mixed with the air sucked through the intake pipe 206 to form an air-fuel mixture, which is used for combustion in the cylinder 201.

  The fuel tank 223 stores fuel supplied from the fuel supply port 311. This fuel is used for combustion of the internal combustion engine 40. The fuel supplied here is, for example, gasoline, alcohol, or a mixed fuel thereof. The pump 225 appropriately sucks up this fuel and supplies it to the fuel injection valve 207. The fuel sensor 224 detects the amount of stored fuel and transmits it to the control device 30.

  The internal combustion engine 40 burns the air-fuel mixture in the cylinder 201 by ignition of the spark plug 202. The reciprocating motion of the piston according to the explosion force at this time is converted into the rotational motion of the crankshaft through the connection rod, and this rotational motion becomes the driving force of the vehicle 1. Various sensors such as a water temperature sensor that detects the temperature of the cooling water and a crank position sensor that can detect the rotation speed of the internal combustion engine 40 by periodically detecting the crank angle are disposed around the internal combustion engine 40. Yes. The output of each sensor is supplied to the control device 30 as a corresponding detection signal. The air-fuel mixture combusted inside the cylinder 201 becomes exhaust gas, passes through the exhaust valve 209 that opens and closes in conjunction with the opening and closing of the intake valve 208, and is exhausted through the exhaust pipe 210. These opening / closing timings are adjusted by, for example, a variable valve operating apparatus configured by a known variable valve timing-intelligent system (VVT-i).

  An air-fuel ratio sensor 221 and an electrically heated catalyst 222 are provided in the pipe line of the exhaust pipe 210.

  The air-fuel ratio sensor 221 is made of, for example, a zirconia solid electrolyte, and detects the air-fuel ratio (A / F) of the exhaust gas in the exhaust pipe 210 and supplies a detection signal to the control device 30. Based on this detection signal, air-fuel ratio feedback correction is performed.

  The electrically heated catalyst (EHC) 222 is a three-way catalyst having a noble metal such as platinum or rhodium as an active component, for example, nitrogen oxide (NOx), carbon monoxide (CO) in exhaust gas, It has a function of removing hydrocarbons (HC) and the like. In addition, the electrically heated catalyst 222 has an electric heater for heating the catalyst that is electrically connected to the control device 30 in order to raise its temperature to an activation temperature (for example, about 350 ° C.). The catalyst temperature sensor 2221 is thermally connected to the electrically heated catalyst 222, detects the temperature of the electrically heated catalyst 222, and transmits the detection result to the control device 30.

  The purge device includes a canister 229, a purge passage 228, a purge control valve 227, and an evaporated fuel concentration sensor 230. The canister 229 includes an adsorbent made of activated carbon inside, and adsorbs the evaporated fuel generated in the fuel tank 223. The purge passage 228 communicates the fuel tank 223, the canister 229, and the intake pipe 206. The purge control valve 227 is provided downstream of the canister 229 in the purge passage 228 and is opened and closed under the control of the control device 30. By opening and closing the purge control valve 227, the evaporated fuel stored in the adsorbent in the canister 229 is appropriately introduced into the intake pipe 206 as a purge gas. Further, an evaporated fuel concentration sensor 230 for detecting the evaporated fuel concentration in the purge gas is attached to the purge passage 228. Even if the evaporative fuel concentration sensor 230 is not provided, the evaporative fuel concentration may be estimated based on a deviation in the feedback correction coefficient that occurs when the purge process is performed, as is well known.

  Here, in particular, at least a part of the purge gas is configured to be introduced into the exhaust pipe 210 in addition to or instead of the intake pipe 206. Specifically, for example, the purge passage 228 branches to the exhaust purge passage 231 downstream of the canister 229. The exhaust purge passage 231 communicates with the exhaust purge passage 234 further downstream, and is configured to be able to introduce at least part of the purge gas into the exhaust pipe 210. The exhaust purge passage 231 may be directly communicated with the canister 229 without branching from the purge passage 228. Here, when the purge gas introduced from the exhaust purge passage 231 is richer than the stoichiometric air-fuel ratio, the energization heating type catalyst 222 may not be able to process the purge gas. Therefore, the atmospheric passage 232 has one end opened to the atmosphere, the other end communicated with the exhaust purge passage 231 and, for example, a check valve is provided in the pipe to mix the atmosphere with the purge gas, thereby reducing the air-fuel ratio of the purge gas. It is configured to be possible. Note that in order to change the mixing ratio between the purge gas introduced from the exhaust purge passage 231 and the atmosphere introduced from the atmosphere passage 232, the pipe of the atmosphere passage 232 has an electromagnetic for adjusting the amount of air to be mixed. An on-off valve may be provided. The canister purge pump 233 is a turbine pump, for example, and adjusts the amount of purge gas mixed with the atmosphere into the exhaust pipe 210. When the purge process is executed, the canister purge pump 233 is driven, and the evaporated fuel adsorbed by the canister 229 is purged to the exhaust pipe 210 through the exhaust purge passage 234 together with the atmosphere introduced from the atmosphere passage 232. Is done.

  The control device 30 includes a central processing unit (CPU), a read only memory (ROM) that stores a control program, and an occasional write / read memory (RAM) that stores various data. It is configured as a central logic operation circuit. The control device 30 is connected to an input port that receives input signals from various sensors such as the catalyst temperature sensor 2221 and an output port that sends control signals to various actuators such as the canister purge pump 233 and the electrically heated catalyst 222 via a bus. It is connected.

  The operation of the hybrid vehicle 1 according to the present embodiment configured as described above will be described with reference to FIGS. 3 and 4.

  FIG. 3 is a flowchart showing a control flow of the canister purge pump in the hybrid vehicle 1 according to the embodiment.

  In FIG. 3, it is first determined whether or not there is a request for starting the hybrid vehicle 1 from the driver to the hybrid vehicle 1 (step S1).

  Here, when there is no start request from the driver (step S1: No), for example, when the vehicle is stopped in the garage, the exhaust gas is not discharged, and therefore it is not necessary to bring the electrically heated catalyst 222 to the activation temperature. Therefore, the subsequent processing is skipped until a start request is received from the driver.

  On the other hand, when there is a start request from the driver (step S1: Yes), preheating is performed by the electrically heated catalyst 222 under the control of the control device 30, that is, the electrically heated catalyst 222 is energized to warm up the air. Do. Then, based on the temperature of the electrically heated catalyst 222 detected by the catalyst temperature sensor 2221, it is determined whether or not warming of the electrically heated catalyst 222 has been completed (step S2). Specifically, it is determined whether or not the condition “temperature of the electrically heated catalyst 222> predetermined activation temperature” is satisfied. In place of the temperature detection value of the electrically heated catalyst 222 by the catalyst temperature sensor 2221, the estimated temperature value estimated from the temperature sensor or the like of another part, the integrated power in the preheating of the electrically heated catalyst 222, the energized time, or the resistance The above determination may be made by comparing values with predetermined threshold values related to these parameters (that is, a threshold value corresponding to the completion of warm-up of the electrically heated catalyst 222).

  Here, when it is determined that the condition “temperature of the electrically heated catalyst 222> predetermined activation temperature” is not satisfied (step S2: No), that is, when the warming of the electrically heated catalyst 222 has not been completed. For this, preheating by the electrically heated catalyst 222 is turned on (step S3.2), that is, the electrically heated catalyst 222 is continuously energized.

  On the other hand, when it is determined that the condition “temperature of the electrically heated catalyst 222> predetermined activation temperature” is satisfied (step S2: Yes), that is, when the warming of the electrically heated catalyst 222 has been completed. In this case, the preheating by the electric heating catalyst 222 is turned off, that is, the electric supply to the electric heating catalyst 222 is stopped (step S3.1).

  Even after the preheating is turned off, the control device 30 satisfies the condition “temperature of the electrically heated catalyst 222 <predetermined activation temperature” based on the temperature of the electrically heated catalyst 222 detected by the catalyst temperature sensor 2221. It is periodically determined whether or not it has been performed (step S4). That is, it is periodically checked whether the temperature of the electrically heated catalyst 222 is lowered and below the activation temperature. In step S4, in order to take a countermeasure before the temperature of the electrically heated catalyst 222 falls below the activation temperature, instead of the above condition, “temperature of the electrically heated catalyst 222 <predetermined activation temperature + minute temperature”. The condition may be determined. Alternatively, instead of the above conditions, a determination may be made based on the temporal change in the temperature of the electrically heated catalyst 222.

  Here, when the condition “temperature of the electrically heated catalyst 222 <predetermined activation temperature” is not satisfied (step S4: No), the temperature of the electrically heated catalyst 222 that has risen due to the preheating becomes equal to the predetermined activation temperature. There is no particular problem because the temperature is maintained above.

  On the other hand, when the condition “temperature of the electrically heated catalyst 222 <predetermined activation temperature” is satisfied (step S4: Yes), the temperature of the electrically heated catalyst 222 that has been raised by the preheating decreases, That is below the activation temperature. Therefore, the control device 30 drives the canister purge pump 233 to introduce the purge gas adsorbed by the canister 229 into the electrically heated catalyst 222 (step S5). Thereby, the warm-up property of the electrically heated catalyst 222 is maintained while performing the purge process. As a result, the temperature of the electrically heated catalyst 222 increases, and it is determined whether or not the condition “temperature of the electrically heated catalyst 222> predetermined activation temperature” is satisfied (step S6). In step S6, in order to stop the canister purge pump 233 before the temperature of the electrically heated catalyst 222 greatly exceeds the activation temperature, instead of the above condition, “temperature of the electrically heated catalyst 222 <predetermined activation temperature”. The condition of “minor temperature” may be determined. Alternatively, instead of the above conditions, a determination may be made based on the temporal change in the temperature of the electrically heated catalyst 222.

  Here, when the condition “temperature of the electrically heated catalyst 222> predetermined activation temperature” is not satisfied (step S6: No), that is, when the temperature of the electrically heated catalyst 222 has not reached the predetermined activation temperature, Next, in order to determine whether or not the canister purge pump 233 can continue to be driven, it is determined whether or not the purge process has been completed (step S7). Whether the purge process is completed is determined based on the detected value or estimated value of the vaporized fuel concentration by the evaporated fuel concentration sensor 23. Alternatively, a purge amount necessary for completing the purge process is determined in advance based on the initial detection value of the vapor deposition fuel concentration, and the determination is made based on whether the purge process for the purge amount has been performed.

  Here, when it is determined that the purge process has not yet been completed (step S7: No), it is considered that vapor deposition fuel for increasing the temperature of the electrically heated catalyst 222 remains in the canister 229. Continue to drive the purge pump 233.

  On the other hand, if it is determined that the purge process is complete (step S7: Yes), the vapor deposition fuel concentration of the purge gas purged to the exhaust pipe 210 via the exhaust purge passage 234 is low, and conversely, May reduce temperature. Therefore, the control device 30 stops the canister purge pump 233 (step S8).

  When the temperature is raised as a result of the purge process and the condition “temperature of the electrically heated catalyst 222> predetermined activation temperature” is satisfied (step S6: Yes), the temperature of the electrically heated catalyst 222 is equal to the predetermined activity. Since the temperature has been reached, the control device 30 stops the canister purge pump 233 (step S8).

  As described above, when the hybrid vehicle 1 operates, the canister purge pump 233 is selectively driven. The points of the flowchart will be described below with reference to the state chart of FIG. Here, FIG. 4 is a state chart showing the state transition in the control of the canister purge pump in the hybrid vehicle 1 according to the embodiment.

  In FIG. 4, the canister purge pump 233 is in a stopped state (ST1) or a driving state (ST2). Hereinafter, the transition between the states will be described in detail. First, immediately after the start request of the hybrid vehicle 1, the canister purge pump 233 is stopped (ST1). Thereafter, preheating of the electrically heated catalyst 222 is performed, but after a while after the completion of preheating, the temperature of the electrically heated catalyst 222 decreases. If it remains as it is, the controller 30 may drive the canister purge pump 233 (ST2). As a result, the purge gas is purged to the exhaust pipe 210 via the exhaust purge passage 234 and combusted in the electrically heated catalyst 222. As a result, if the temperature of the electrically heated catalyst 222 rises and exceeds the activation temperature, the canister purge pump 233 is stopped again (ST1).

  According to the embodiment described above, when there is a start request from the driver, the electrically heated catalyst 222 can be maintained in an active state in advance in preparation for the operation of the internal combustion engine 40. At this time, since the canister purge pump 233 is selectively driven in addition to heating by energization of the energization heating type catalyst 222, power consumption can be suppressed and an opportunity for purge processing can be secured.

  In the above embodiment, the hybrid vehicle 1 is an example of the “hybrid vehicle” according to the present invention, the internal combustion engine 40 is an example of the “internal combustion engine” according to the present invention, and the motor generator is according to the present invention. The “electric generator” and the “motor” are examples of the “electric generator” and the “electric motor”, and the electrically heated catalyst 222 is an example of the “catalyst” and the “heating means” according to the present invention, and canisters 229, a purge passage 228, an exhaust purge passage 231 and The exhaust purge passage 234 is an example of the “exhaust purge unit” according to the present invention, the canister purge pump 233 is an example of the “adjusting unit” according to the present invention, and the catalyst temperature sensor 2221 is “ The control device 30 is an example of the “control means” according to the present invention, and the evaporated fuel concentration sensor 230 is the “concentration characteristic” according to the present invention. Is an example of means ", the air passage 232 is an example of the" air introduction section "of the present invention.

  The present invention is not limited to the above-described embodiment, and can be appropriately changed without departing from the spirit or idea of the invention that can be read from the claims and the entire specification. The control device is also included in the technical scope of the present invention.

1 is a schematic top view showing a hybrid vehicle 1 according to an embodiment of the present invention. 1 is a schematic cross-sectional view showing an internal combustion engine 40 according to an embodiment. It is a flowchart which shows the control flow of the canister purge pump in the hybrid vehicle 1 which concerns on embodiment. It is a state chart which shows the state transition in control of the canister purge pump in the hybrid vehicle 1 which concerns on embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Hybrid vehicle, 20R, 20L ... Front wheel, 22R, 22 ... Rear wheel, 40 ... Internal combustion engine, B ... Battery, 20 ... Boosting unit, 14 ... Inverter, MG1, MG2 ... Motor generator, 206 ... Intake pipe, 201 ... Cylinder, 2061 ... Surge tank, 2062 ... Pressure sensor, 207 ... Fuel injection valve, 30 ... Control device, 202 ... Spark plug, 223 ... Fuel tank, 311 ... Filling port, 224 ... Fuel sensor, 208 ... Intake valve, 209 ... Exhaust valve, 210 ... exhaust pipe, 221 ... air-fuel ratio sensor, 222 ... electrically heated catalyst, 2221 ... catalyst temperature sensor, 229 ... canister, 228 ... purge passage, 227 ... purge control valve, 230 ... evaporated fuel concentration sensor, 231 ... exhaust purge passage, 232 ... atmosphere passage, 233 ... canister purge pump, 234 ... exhaust purge passage , 2221 ... the catalyst temperature sensor

Claims (7)

An internal combustion engine that generates power by burning fuel, a generator that generates power using at least part of the generated power and charges the battery with electric power obtained by the power generation, and a discharge that is discharged from the battery A control device for a hybrid vehicle comprising an electric motor that outputs power according to electric power,
Heating means for heating the catalyst provided in the pipe of the exhaust pipe in order to purify the exhaust gas discharged along with combustion in the internal combustion engine according to the amount of current supplied to the heating means;
An exhaust purge means for introducing the evaporated fuel in the fuel tank for storing the fuel as a purge gas from the canister for adsorbing the evaporated fuel to the upstream side of the catalyst in the exhaust pipe;
Adjusting means for adjusting the amount of purge gas introduced by the exhaust purge means;
Temperature specifying means for specifying the temperature of the catalyst;
A hybrid vehicle comprising: control means for controlling an energization amount to the heating means and a driving state of the adjusting means based on at least the temperature of the specified catalyst and the running state of the hybrid vehicle. Control device. The control means includes
Energize the heating means before the start request of the internal combustion engine,
When the temperature of the specified catalyst exceeds a predetermined activation temperature, the power supply to the heating unit is stopped, and the adjusting unit is driven to introduce the purge gas into the exhaust pipe. The hybrid vehicle control device according to claim 1. A concentration specifying means for specifying the concentration of the evaporated fuel in the purge gas;
The control device for a hybrid vehicle according to claim 2, wherein the control means stops driving the adjustment means when the concentration of the specified evaporated fuel falls below a predetermined concentration threshold value. The control means changes the drive state of the adjusting means so that the temperature of the specified catalyst is maintained at a predetermined activation temperature after the energization of the heating means is stopped until the start request of the internal combustion engine. The hybrid vehicle control device according to claim 2, wherein the control device controls the hybrid vehicle. The said control means restarts the electricity supply to the said heating means, when the temperature of the said specified catalyst falls below the said predetermined activation temperature after stopping the electricity supply to the said heating means. The control apparatus of the hybrid vehicle as described in 2. The control apparatus for a hybrid vehicle according to claim 1, further comprising air introduction means for mixing air with purge gas introduced by the exhaust purge means. The hybrid vehicle according to any one of claims 1 to 6, wherein the hybrid vehicle starts the internal combustion engine in response to a high load request even when the remaining charge of the battery is sufficient. Control device.

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