JP2008265357A - Electric heating type catalyst device and control method for electric heating type catalyst - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electric heating type catalyst device provided in a hybrid vehicle capable of exhibiting a high cleaning function even immediately after an engine starts. <P>SOLUTION: The electric heating type catalyst device includes a catalyst (120) provided in an exhaust passage of an internal combustion engine (200) of a hybrid vehicle (10), a heating means (120) capable of heating the catalyst by energizing, a communication means (110) provided on the vehicle for communicating with a roadside device (700) of an electronic toll collection system of a toll road, and a control means (100) for controlling the heating means so that the catalyst is heated when communication is performed. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a technical field of an electrically heated catalyst device provided in a hybrid vehicle and a method for controlling the electrically heated catalyst.

  As this type of electric heating type catalyst device, there is one that increases the reaction rate of the catalyst and improves the exhaust gas purification function by heating the catalyst in advance.

  For example, in a catalyst provided in a hybrid vehicle, a technique is disclosed in which a catalyst is exerted with a high purification function even immediately after the engine is started by heating the catalyst while traveling only with an electric motor. (See Patent Document 1).

  On the other hand, in a hybrid vehicle, when an approach signal from an automatic toll collection system (ETC: Electronic Toll Collection System) is received, a technique is disclosed in which intermittent engine operation is prohibited in preparation for high-speed operation (Patent Literature). 2).

JP 2002-52522 A JP 2006-321345 A

  However, in the technology of preheating the catalyst described above, the timing for starting heating is important.If the timing is too early, the power for heating is wasted, and if the timing is too late, There is a technical problem that heating is not in time and sufficient effects cannot be obtained. In other words, the effect of heating the catalyst cannot be sufficiently obtained unless it is possible to accurately determine when the vehicle starts to travel at high speed.

  The present invention has been made in view of the above-described problems, for example, and it is an object of the present invention to provide an electrically heated catalyst device and an electrically heated catalyst control method capable of exhibiting a high purification function even immediately after engine startup. And

  In order to solve the above problems, an electrically heated catalyst device of the present invention is provided with a catalyst provided in an exhaust path of an internal combustion engine in a hybrid vehicle, heating means capable of heating the catalyst by energization, and the vehicle. Communication means for communicating with a roadside device of an automatic toll collection system for a toll road, and control means for controlling the heating means so as to heat the catalyst when the communication is performed. .

  According to the electrically heated catalyst device of the present invention, when a hybrid vehicle travels, travel using only an electric motor (hereinafter referred to as “EV travel” as appropriate), travel using both an electric motor and an internal combustion engine. When switching to (hereinafter referred to as “HV traveling” as appropriate), the purification function of the catalyst provided in the exhaust path can be sufficiently exhibited even immediately after the internal combustion engine is started. That is, by energizing the heating means, the catalyst can be heated during EV traveling. Therefore, even immediately after switching to HV traveling (that is, immediately after starting the internal combustion engine), the temperature of the catalyst is sufficiently increased, so that the exhaust gas can be appropriately purified. The “heating means” in the present invention may heat the catalyst directly or indirectly. For example, even if the catalyst is heated as a result of heating a member disposed around the catalyst, the effect of the present invention can be sufficiently obtained.

  In the present invention, in particular, the heating start timing of the catalyst by the heating means described above is when communication with the ETC system on the toll road is performed, whereby heating can be performed at a more appropriate timing. Here, “when communication is performed” means, for example, immediately or without delay as much as possible as the operation of the apparatus, or after a predetermined time after it is detected that communication has been performed. In other words, it means that communication is performed or that communication is detected is used as a trigger (ie, trigger or trigger). More specifically, for example, when a vehicle traveling on a general road in EV traveling enters an expressway, the communication means provided on the vehicle when passing through an ETC gate provided at the entrance of the expressway Is communicated with the roadside device of the ETC system, and heating of the catalyst by the heating means is started with the communication as a trigger.

  The vehicle that has passed through the ETC gate then starts high-speed travel (for example, travel exceeding 80 km / h) on the highway. For this reason, the vehicle which was EV driving | running | working should switch to HV driving | running | working with higher output. Therefore, it is possible to predict the presence / absence and timing of switching to HV traveling (that is, starting of the internal combustion engine) that will be implemented in the near future from the presence / absence and timing of communication with the ETC system. Therefore, heating can be started at a more appropriate timing by setting the catalyst heating start timing when communication with the ETC system is performed. That is, when the catalyst is preheated, the heating start timing is too early, power for heating is consumed wastefully, and the timing is too late, resulting in insufficient heating. Can be prevented.

  As described above, according to the electrically heated catalyst device of the present invention, the catalyst purification function can be sufficiently exerted even immediately after the start of the internal combustion engine by starting the heating of the catalyst at an appropriate timing. Can be made. Therefore, the effect of improving the exhaust emission can be obtained.

  In one aspect of the electrically heated catalyst device of the present invention, the heating means heats the catalyst to reach a predetermined temperature before the vehicle joins the main road of the toll road.

  According to this aspect, when the communication means communicates with the roadside device of the ETC system and the heating of the catalyst by the heating means is started, the catalyst reaches a predetermined temperature before the vehicle joins the main road of the toll road. Heated. Here, the “predetermined temperature” is a temperature at which a reaction for purifying exhaust gas is sufficiently performed in the catalyst, for example, a temperature of about 400 to 500 degrees Celsius.

  For example, on an expressway, it takes from several tens of seconds to several tens of seconds from passing through the ETC gate to joining the main line. Therefore, if heating is performed to reach a predetermined temperature in this time, the reaction in the catalyst is sufficiently performed even immediately after the engine is started. Therefore, the catalyst purification function can be fully exerted, and exhaust emission can be improved. If there is a margin in the heating capacity of the heating means, “when communication is performed”, for example, after a predetermined time such as several seconds after passing through the ETC gate, heating may be started. . Alternatively, if there is no margin in the heating capability of the heating means, for example, heating may be started immediately after passing through the ETC gate.

  In another aspect of the electrically heated catalyst device of the present invention, the control means controls the heating means to stop the heating when the catalyst reaches the predetermined temperature.

  According to this aspect, the heating means is controlled by the control means to stop heating when the catalyst reaches a predetermined temperature. As a result, it is possible to prevent the wasteful consumption of electric power for heating as a result of continuing heating even when the catalyst reaches a temperature at which the purification function can be sufficiently exerted.

  In addition, it is possible to prevent the deterioration of the function of the catalyst due to the temperature being too high, and the situation where the members disposed in the vicinity exceed the heat resistance temperature and do not function normally.

  In another aspect of the electrically heated catalyst device of the present invention, the control means controls the heating means so as to stop the heating when the internal combustion engine is operated.

  According to this aspect, the heating means is controlled by the control means so as to stop the heating when the internal combustion engine is operated.

  When the internal combustion engine operates, hot exhaust gas is sent to the catalyst. For this reason, when the internal combustion engine is operated, even if the catalyst does not reach the predetermined temperature, the catalyst is heated by the exhaust gas and reaches the predetermined temperature. In other words, if the heating means is used during the operation of the internal combustion engine, power is wasted.

  However, particularly in the present invention, when the internal combustion engine is operated, the heating means is controlled to stop heating. Therefore, heating by the heating means is not performed during operation of the internal combustion engine, and the catalyst is heated by the exhaust gas sent from the internal combustion engine through the exhaust path. Therefore, it is possible to prevent wasteful power consumption by the heating means.

  In another aspect of the electrically heated catalyst device of the present invention, the control means has a determination means for determining whether or not the internal combustion engine is operating, and the internal combustion engine is operated by the determination means. When it is determined that the heating means is not present, the heating means is controlled.

  According to this aspect, for example, when communication is performed by the communication unit, the determination unit determines whether or not the internal combustion engine is operating, and when it is determined that the internal combustion engine is not operating, the heating unit The catalyst is heated by.

  For example, when passing through an ETC gate, the vehicle may already be running HV. In such a case, since the catalyst has already reached the predetermined temperature or is heated by the exhaust gas even if it has not reached the predetermined temperature, it does not have to be heated using the heating means. Therefore, when the internal combustion engine is operating, it is possible to prevent wasteful power consumption by not controlling the heating means.

  In another aspect of the electrically heated catalyst device of the present invention, the vehicle can be charged into a rechargeable battery provided in the vehicle by a method other than power generation by operation of the internal combustion engine. It is.

  According to this aspect, the catalyst is provided in a plug-in hybrid type vehicle, and a rechargeable battery provided in the vehicle by a method other than power generation by the operation of the internal combustion engine (for example, a household outlet). Can be charged.

  As described above, since the plug-in hybrid vehicle can be charged by a method other than power generation, the battery capacity is increased as compared with a normal hybrid vehicle. For this reason, the EV travelable distance is also longer than that of a normal hybrid vehicle.

  As the EV travelable distance increases, the possibility of traveling without operating the internal combustion engine when passing through the ETC gate increases. Therefore, by starting the heating of the catalyst during the communication with the ETC system described above, it is possible to more reliably obtain the effect of sufficiently exerting the purification function of the catalyst when switching to the HV traveling.

  In order to solve the above-described problems, a method for controlling an electrically heated catalyst according to the present invention is a hybrid vehicle equipped with a catalyst provided in an exhaust path of an internal combustion engine and heating means that can be heated by energizing the catalyst. A communication step of communicating with a roadside device of an automatic toll collection system on a toll road by communication means provided in the vehicle, and the heating so as to start heating of the catalyst when the communication is performed And a control step for controlling the means.

  According to the method for controlling an electrically heated catalyst according to the present invention, heating can be started at an appropriate timing by setting the catalyst heating start timing when communication with the ETC system is performed. Therefore, even immediately after the start of the internal combustion engine, the catalyst purification function can be sufficiently exerted, and the effect of improving the exhaust emission can be obtained.

  In addition, also in the control method of the electrically heated catalyst of this invention, it is possible to take the various aspects similar to the various aspects in the electrically heated catalyst apparatus of this invention mentioned above.

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

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

<First Embodiment>
First, a configuration of a hybrid vehicle provided with the electrically heated catalyst device according to the present embodiment will be described with reference to FIG. FIG. 1 is a schematic diagram showing the configuration of the hybrid vehicle. The configuration of the electrically heated catalyst device is not shown here because it will be described in detail later.

  In FIG. 1, a hybrid vehicle (hereinafter, referred to as “vehicle” as appropriate) 10 mainly includes an axle 11, wheels 12, an ECU (Electronic Control Unit) 100, an engine (internal combustion engine) 200, and a motor generator MG1. (Hereinafter referred to as “MG1” as appropriate) and motor generator MG2 (hereinafter referred to as “MG2” as appropriate), power split mechanism 300, inverter 400, battery 500, and SOC (State Of Charge) sensor 600. It is prepared for.

  The axle 11 is a part of a power transmission system that transmits the power of the engine 200 and the MG 2 to the wheels 12. The wheel 12 is a wheel of the vehicle 10, and only the left and right front wheels are particularly shown in FIG. The engine 200 is constituted by a gasoline engine or the like, and functions as a main power source of the vehicle 10.

  MG1 is configured to function mainly as a generator for charging battery 500 or a generator for supplying power to motor MG2. Motor MG2 is configured to function mainly as an electric motor that assists the output of engine 200. These motors MG1 and MG2 are configured as, for example, synchronous motor generators, and include a rotor having a plurality of permanent magnets on the outer peripheral surface, and a stator wound with a three-phase coil that forms a rotating magnetic field. Power split device 300 is configured to be able to distribute the output of engine 200 to MG 1 and axle 11.

  Inverter 400 is a DC / AC converter that controls input / output of power between battery 500 and MG1 and MG2. For example, the inverter 400 converts the DC power extracted from the battery 500 into AC power, or supplies AC power generated by the MG1 to the MG2, respectively, and converts AC power generated by the MG1 into DC power. Thus, the battery 500 can be supplied.

  Battery 500 is a rechargeable rechargeable battery configured to be able to function as a power source for driving MG1 and MG2. The SOC sensor 600 is a sensor configured to be able to detect the state of charge of the battery 500. The SOC sensor 600 is electrically connected to the ECU 100, and the SOC of the battery 500 is always grasped by the ECU 100.

  The ECU 100 is an example of the “control unit” of the present invention, and includes an unillustrated CPU (Central Processing Unit), ROM (Read Only Memory), and RAM (Random Access Memory), and electronic control that controls the overall operation of the vehicle 10. Is a unit. In the present embodiment, the ECU 100 is based on the target charge amount of the battery 500 (hereinafter referred to as “control target SOC”), the driver's required output (that is, accelerator opening), and the like from the engine 200. , Charging of the battery 500 (regeneration by MG1), and discharging of the battery 500 (assisting the output of the engine 200 using the output of MG2) are controlled. That is, ECU 100 basically controls the engine output and charging / discharging of battery 500 such that the SOC of battery 500 is maintained at the control target SOC while the driver's required output is satisfied.

  Note that the hybrid vehicle 10 according to the present embodiment may be a plug-in hybrid vehicle that can charge the battery 500 from a household outlet or the like, for example.

  Next, the configuration of the electrically heated catalyst device according to this embodiment will be described with reference to FIGS. FIG. 2 is a side view showing the configuration of the electrically heated catalyst device. 3 to 5 are schematic views showing specific arrangement examples of the electrically heated catalyst device.

  In FIG. 2, the electrically heated catalyst device includes the ECU 100 described above, the communication unit 110 that is an example of the “communication means” of the present invention, and the electrically heated type that is an example of the “catalyst” and the “heating means” of the present invention. And a catalyst (EHC: Electrically Heated Catalyst) 120.

  The communication unit 110 is, for example, an ETC vehicle-mounted device provided inside the vehicle, and communicates with an ETC roadside device 700 such as an ETC gate provided at an entrance of an expressway or the like. The communication unit 110 is electrically connected to the ECU 100, and is configured to send an electric signal to the ECU 100 when communication with the ETC roadside device 700 is performed.

The electrically heated catalyst 120 is provided in the exhaust path of the engine 200 (see FIG. 1), and removes harmful components such as CO, HC, NOx, etc. contained in the exhaust gas without harming H ₂ O, CO ₂ , N Discharge as ₂ mag. Moreover, it has the heater which is not shown in figure, and can raise the reaction rate of the reaction which detoxifies the harmful | toxic component mentioned above by supplying electricity to a heater and heating a catalyst. Furthermore, a temperature sensor (not shown) for detecting the temperature of the electrically heated catalyst 120 is provided in the electrically heated catalyst 120 or a member disposed in the vicinity thereof. Below, the specific example of arrangement | positioning of the electrically heated catalyst 120 is shown.

  In FIG. 3, the electrically heated catalyst 120 is disposed adjacent to the underfloor catalyst 140 between the start catalyst 130 and the sub-muffler 150. With such an arrangement, exhaust gas can be purified by the three catalysts of the electrically heated catalyst 120, the start catalyst 130, and the underfloor catalyst 140, so that the overall purification capability can be enhanced.

  In FIG. 4, for example, if the purification capability of the electrically heated catalyst 120 and the underfloor catalyst 150 is high, the start catalyst 130 may be omitted.

  In FIG. 5, if the purification capability of the electrically heated catalyst 120 is higher, it is possible to adopt a configuration in which the catalyst is only the electrically heated catalyst 120 without arranging the underfloor catalyst 150.

  The arrangement examples of the electric heating catalyst 120 described here are merely examples, and the electric heating catalyst 120 can be arranged at a position different from such a position.

  Next, the operation and effect of the electrically heated catalyst device according to this embodiment will be described with reference to FIG. 6 in addition to FIG. FIG. 6 is a flowchart showing the operation of the electrically heated catalyst device according to the first embodiment.

  2 and 6, it is assumed that the vehicle 10 enters an ETC gate provided at the entrance of an expressway from a general road, for example. In this case, when the vehicle 10 approaches the ETC gate, the communication unit 110 receives an approach signal transmitted from the ETC roadside device 700 provided at the ETC gate (step S1). When the approach signal is received (step S1: YES), an electrical signal is sent from the communication unit 110 to the ECU 100 to notify that communication with the ETC roadside device 700 has been performed.

  When communication is performed, ECU 100 first determines whether or not engine 200 is operating (step S3). Here, if it is determined that engine 200 is operating (step S3: YES), the process is terminated. If it is determined that engine 200 is not operating (step S3: NO), the process proceeds to step S4.

  When the engine 200 is not operating, the ECU 100 starts heating the electric heating catalyst 120 immediately or after a predetermined time has elapsed in advance from 0 to several seconds depending on the heating capacity of the electric heating catalyst 120. (Step S4). Note that the predetermined time in this case may be a fixed value set in advance, or may be a variable value that changes in accordance with the operating environment such as engine temperature and air temperature.

  The electrically heated catalyst 120 is heated to, for example, about 400 degrees Celsius to about 500 degrees Celsius before the vehicle 10 joins the main road of the highway, and the heating is finished (Step S5). The temperature after heating of the electrically heated catalyst 120 is determined by, for example, the material constituting the electrically heated catalyst 120 and the heat resistant temperature.

  Finally, when the vehicle 10 joins the main road of the highway, the vehicle 10 travels at a high speed, and the engine 200 is started to obtain a high output (step S7). At this time, since the electrically heated catalyst 120 is preheated as described above, the purification function can be sufficiently exerted even immediately after the engine 200 is started. Therefore, exhaust emission can be improved.

Second Embodiment
Next, an electrically heated catalyst device according to a second embodiment will be described with reference to FIG. FIG. 7 is a flowchart showing the operation of the electrically heated catalyst device according to the second embodiment. Note that the second embodiment differs from the first embodiment described above in the process from the start to the end of heating of the electrically heated catalyst device 120, and the configuration of the device and other operations are different. It is almost the same. For this reason, operation | movement of the electrically heated catalyst apparatus 120 is demonstrated in detail here, and description is abbreviate | omitted suitably about the part similar to 1st Embodiment.

  In FIG. 7, from step S <b> 1 to step S <b> 4, the same processing as in the first embodiment described above is performed, and heating of the electrically heated catalyst 120 is started.

  When heating of the electrically heated catalyst 120 is started, the ECU 100 determines whether or not the engine has been operated (step S8). Here, if it is determined that the engine has been operated (step S8: YES), the process proceeds to step S5, the heating is terminated, and the process is terminated. If it is determined that the engine is not operating (step S8: NO), the process proceeds to step S9.

  Next, the ECU 100 determines whether or not the temperature of the electrically heated catalyst 120 has reached a predetermined temperature T (step S9). Here, if the temperature of the electrically heated catalyst 120 has reached the predetermined temperature T (step S9: YES), the process proceeds to step S5, where the heating is terminated and the process is terminated. If it is determined that the temperature of the electrically heated catalyst 120 has not reached the predetermined temperature T (step S9: NO), the process returns to step S8 again. Therefore, heating of the electrically heated catalyst 120 is performed until the engine is operated or until the electrically heated catalyst 120 reaches a predetermined temperature T.

  As described above, in the second embodiment, the timing for terminating the heating of the electrically heated catalyst 120 is determined when the engine is operated and when the electrically heated catalyst 120 reaches a predetermined temperature T. It is possible to prevent useless power consumption by the heating means.

  The present invention is not limited to the above-described embodiment, and can be appropriately changed without departing from the gist or concept of the invention that can be read from the claims and the entire specification, and an electrically heated catalyst with such a change. The apparatus and the method for controlling the electrically heated catalyst are also included in the technical scope of the present invention.

It is the schematic which shows the structure of a hybrid vehicle. It is a side view which shows the structure of an electrically heated catalyst apparatus. It is the schematic (the 1) which shows the specific example of arrangement | positioning of an electrically heated catalyst. It is the schematic (the 2) which shows the specific example of arrangement | positioning of an electrically heated catalyst. It is the schematic (the 3) which shows the specific example of arrangement | positioning of an electrically heated catalyst. It is a flowchart which shows operation | movement of the electric heating type catalyst apparatus which concerns on 1st Embodiment. It is a flowchart which shows operation | movement of the electrically heated catalyst apparatus which concerns on 2nd Embodiment.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Hybrid vehicle, 11 ... Axle, 12 ... Wheel, 100 ... ECU, 110 ... Communication part, 120 ... Electric heating catalyst, 200 ... Engine, 300 ... Power split mechanism, 400 ... Inverter, 500 ... Battery, 600 ... SOC Sensor, 700 ... ETC roadside device

Claims (7)

A catalyst provided in an exhaust path of an internal combustion engine in a hybrid vehicle;
Heating means capable of heating the catalyst by energization;
A communication means provided in the vehicle for communicating with a roadside device of an automatic toll collection system for a toll road;
An electric heating type catalyst device comprising: control means for controlling the heating means so as to heat the catalyst when the communication is performed.   The electric heating catalyst device according to claim 1, wherein the heating means heats the catalyst so as to reach a predetermined temperature before the vehicle joins the main road of the toll road.   The electric heating catalyst device according to claim 1, wherein the control unit controls the heating unit to stop the heating when the catalyst reaches the predetermined temperature.   4. The electrically heated catalyst device according to claim 1, wherein the control unit controls the heating unit to stop the heating when the internal combustion engine is operated. 5. .   The control means includes determination means for determining whether or not the internal combustion engine is operating, and controls the heating means when the determination means determines that the internal combustion engine is not operating. The electrically heated catalyst device according to any one of claims 1 to 4, wherein:   6. The plug-in hybrid type vehicle, wherein the vehicle is capable of charging a rechargeable battery provided in the vehicle by a method other than power generation by the operation of the internal combustion engine. The electrically heated catalyst device according to claim 1. In a hybrid vehicle including a catalyst provided in an exhaust path of an internal combustion engine and heating means that can be heated by energizing the catalyst,
A communication step of communicating with a roadside device of an automatic toll collection system on a toll road by means of communication means provided in the vehicle;
A control step of controlling the heating means so as to start heating of the catalyst when the communication is performed.

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