JP2007022157A - Charge controlling device for vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a charge controlling device for vehicle which prevents the deterioration of the drivability of a vehicle from occurring by forcible charge at the time of deceleration. <P>SOLUTION: This charge controlling device for a vehicle 40 which loads an engine 1 is equipped with: an alternator 13 being driven by the engine 1; and a battery 14 which charges generated power by the alternator 13. At the time of speed reduction, a generated voltage of the alternator 13 is increased, and the generated power by the alternator 13 is forcibly charged to the battery 14. Also, the charge controlling device for vehicle is equipped with an output adjusting means for slightly increasing the output of the engine when the load of the engine 1 is increased by the forcible charge at the time of speed reduction. The output adjusting means includes: a bypass passage 11 which is provided in an air suction passage 2 by bypassing a throttle valve 5; an idle speed control valve (IS valve) 12 which is provided in the passage 11; and an electronic control unit (ECU) 30 which opening/closing-controls the ISC valve 12 while adjusting to the forcible charge. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention includes an alternator that is provided in a vehicle equipped with an engine and is driven by the engine, and a battery that charges electric power generated by the alternator. The present invention relates to a vehicular charge control device that performs control to forcibly charge electric power to a battery.

  Conventionally, as this type of charge control device, for example, techniques described in Patent Documents 1 and 2 below are known. The prior art described in Patent Document 1 relates to a deceleration energy regeneration device that regenerates deceleration energy of a vehicle by charging a battery with electric power generated by an alternator during vehicle braking or the like. In this device, when the vehicle is decelerated by applying a brake, the vehicle is coasted by inertial energy and the engine is rotated by inertia, thereby generating electric power with an alternator and charging the battery with the electric power.

  The prior art described in Patent Document 2 increases the power generation voltage of the generator (alternator) when the engine decelerates to forcibly charge the battery, and after the forcible charging, the amount of charge made to the battery during the forcible charging The power generation voltage of the alternator is lowered for a predetermined time corresponding to the power to make no power generation. As a result, it is possible to discharge during no power generation by an amount corresponding to the amount of electric power collected by forced charging, and to prevent performance deterioration due to battery charge state deterioration while satisfying fuel efficiency improvement and engine rotation reduction prevention. Yes.

JP-A-10-285706 JP 2003-244998 A

  However, in the prior art described in Patent Document 2, the load on the alternator increases by increasing the power generation voltage of the alternator when the engine decelerates and forcibly charging the battery. Therefore, when the vehicle stops after deceleration, the engine rotates rapidly. There was a risk of the engine stalling. In addition, the engine may be vibrated due to a sudden decrease in rotation of the engine, which may deteriorate the drivability of the vehicle.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a vehicle charge control device capable of preventing deterioration of vehicle drivability due to forced charging during deceleration.

  In order to achieve the above object, an invention according to claim 1 is a vehicle charge control device provided in a vehicle equipped with an engine, wherein the alternator driven by the engine and the electric power generated by the alternator are charged. A vehicle charging control device for controlling the power generated by the alternator to be forcibly charged to the battery by increasing the generated voltage of the alternator when the vehicle decelerates, and when the load on the engine increases due to forced charging The purpose is to provide an output adjusting means for slightly increasing the output of the engine.

  According to the configuration of the invention, when the vehicle is decelerated, the power generation voltage of the alternator is increased to generate power, and the power is forcibly charged to the battery. At this time, the engine load is increased by increasing the power generation voltage of the alternator. However, when the engine load increases due to forced charging, the output adjusting means slightly increases the engine output. It can be suppressed.

  In order to achieve the above object, according to a second aspect of the present invention, in the first aspect of the present invention, the output adjustment means includes an intake adjustment means provided in an intake passage of the engine, and the intake adjustment means for forced charging. It is intended to include control means for driving and controlling together.

  According to the configuration of the invention, when the vehicle is decelerated, the power generation voltage of the alternator is increased to generate power, and the power is forcibly charged to the battery. At this time, the engine load is increased by increasing the power generation voltage of the alternator. However, when the engine load increases due to forced charging, the control means drives the intake adjustment means to slightly increase the engine output. Sudden engine speed reduction is suppressed.

  In order to achieve the above object, according to a third aspect of the present invention, in the first aspect of the present invention, the output adjusting means includes a bypass passage provided around the throttle valve in the intake passage of the engine, and a bypass passage. And an electronic control device that controls opening and closing of the idle speed control valve in accordance with forced charging.

  According to the configuration of the invention, when the vehicle is decelerated, the power generation voltage of the alternator is increased to generate power, and the power is forcibly charged to the battery. At this time, the engine load increases by increasing the power generation voltage of the alternator, but when the engine load increases due to forced charging, the electronic control unit controls the opening / closing of the idle speed control valve to Since the amount of intake air flowing through the bypass passage bypassing the valve is adjusted and the engine output slightly increases, a sudden decrease in the rotation of the engine is suppressed.

  According to the invention described in any one of claims 1 to 3, it is possible to prevent the drivability of the vehicle from deteriorating during forced charging.

  Hereinafter, an embodiment of a vehicle charge control device according to the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a schematic configuration diagram showing an engine system including a vehicle charging control apparatus according to this embodiment. This engine system includes a multi-cylinder engine 1 mounted on a vehicle 40. The engine 1 explodes and burns a combustible mixture of fuel and air supplied through an intake passage 2 in a combustion chamber of each cylinder, and discharges the exhaust after combustion into an exhaust passage 3 to provide a piston (not shown). ) Is operated to rotate the crankshaft 4 to obtain power. The power of the engine 1 is transmitted to the drive wheels 41 of the vehicle 40.

  A throttle valve 5 provided in the intake passage 2 is opened and closed to adjust the amount of air (intake air amount) Ga that flows through the passage 2 and is sucked into each cylinder. The valve 5 is opened and closed by operating an accelerator pedal 6 provided at the driver's seat. A throttle sensor 21 provided for the throttle valve 5 detects an opening degree (throttle opening degree) TA of the valve 5 and outputs an electric signal corresponding to the detected value. Further, the throttle sensor 21 outputs an idle signal idS (ON signal) indicating that the throttle valve 5 is fully closed. An air flow meter 22 provided in the intake passage 2 measures the intake air amount Ga sucked into each cylinder through the intake passage 2 and outputs an electric signal corresponding to the measured value.

  A plurality of fuel injection valves (injectors) 7 provided corresponding to each cylinder injects fuel into the intake port of each cylinder. The fuel is pumped and supplied to each injector 7 by a fuel supply device (not shown). The fuel supplied to the injector 7 is injected when the injector 7 is opened by energization.

  The spark plug 8 provided in the engine 1 corresponding to each cylinder operates by receiving a high voltage output from the igniter 9. The ignition timing of each spark plug 8 is determined by the output timing of the high voltage output from the igniter 9. That is, the ignition timing by the spark plug 8 is controlled by controlling the igniter 9.

  An oxygen sensor 23 is provided in the exhaust passage 3. The oxygen sensor 23 detects the oxygen concentration Ox in the exhaust discharged from the engine 1 to the exhaust passage 3, and outputs an electrical signal corresponding to the detected value. A rotational speed sensor 24 provided in the engine 1 detects the rotational angular speed of the crankshaft 4, that is, the engine rotational speed NE, and outputs an electrical signal corresponding to the detected value. A water temperature sensor 25 provided in the engine 1 detects the temperature (cooling water temperature) THW of the cooling water flowing inside the engine 1 and outputs an electrical signal corresponding to the detected value.

  The intake passage 2 is provided with a bypass passage 11 that bypasses the throttle valve 5. The bypass passage 11 is provided with an idle speed control valve (ISC valve) 12 for opening and closing the passage 11. The ISC valve 12 is a valve that is electrically opened and closed, and is provided so that the amount of air flowing through the bypass passage 11 (ISC flow rate) can be finely adjusted. In this embodiment, the bypass passage 11 and the ISC valve 12 constitute the intake air adjusting means of the present invention.

  The charge control device of this embodiment includes an alternator 13 driven by the engine 1 and a battery 14 that charges power generated by the alternator 13. The alternator 13 and the battery 14 are respectively connected to a plurality of electric devices 15 (corresponding to electric loads) related to the engine 1 and supply electric power to these electric devices 15.

  In this embodiment, the electronic control unit (ECU) 30 inputs various signals output from the throttle sensor 21, the air flow meter 22, the oxygen sensor 23, the rotation speed sensor 24, and the water temperature sensor 25. The ECU 30 executes fuel injection control and ignition timing control based on these input signals, and controls each injector 7 and igniter 9. Further, the ECU 30 executes charge control and controls the ISC valve 12 and the alternator 13.

  Here, the fuel injection control is to control the fuel injection amount and the fuel injection timing by controlling each injector 7 in accordance with the operating state of the engine 1. The ignition timing control is to control the ignition timing by each spark plug 8 by controlling the igniter 9 according to the operating state of the engine 1. The charge control is performed by controlling the alternator 13 to control charging from the alternator 13 to the battery 14 and for increasing the output of the engine 1 slightly when the load of the engine 1 increases due to forced charging during deceleration. Including controlling the valve 12.

  In this embodiment, the ECU 30 has a known configuration including a central processing unit (CPU), a read only memory (ROM), a random access memory (RAM), a backup RAM, and the like. The ROM stores in advance predetermined control programs related to the various controls described above. The ECU (CPU) 30 executes the various controls described above according to these control programs. In this embodiment, the ECU 30 corresponds to the control means of the present invention. Further, the bypass passage 11, the ISC valve 12 and the ECU 30 constitute the output adjusting means of the present invention.

  Next, the contents of the charge control executed by the ECU 30 will be described. FIG. 2 is a flowchart showing the “charge control routine”. The ECU 30 periodically executes this routine every predetermined time.

  During operation of the engine 1, in step 100, the ECU 30 determines whether or not the engine is decelerating. The ECU 30 determines this determination based on the presence or absence of the idle signal idS output from the throttle sensor 21. If the determination result is affirmative, the ECU 30 proceeds to step 110.

  In step 110, the ECU 30 determines whether or not charging regeneration control is performed during deceleration. That is, it is determined whether or not control is performed to apply the inertial rotational force of the drive wheels 41 accompanying the deceleration operation to the alternator 13 via the engine 1 and forcibly charge the battery 14 with the electric power generated by the alternator 13. When this charge regeneration control is executed, the ECU 30 changes the alternator load aLD by changing the charging voltage cVO for the battery 14. If the determination result in step 110 is affirmative, the ECU 30 proceeds to step 120.

  In step 120, the ECU 30 determines whether or not the engine rotational speed NE detected by the rotational speed sensor 24 is equal to or less than a value obtained by adding a predetermined set value α to the target engine rotational speed tNE during the charge regeneration control. . If this determination result is affirmative, the ECU 30 proceeds to step 130.

  In step 130, the ECU 30 calculates an engine rotation speed deviation dNE. That is, the ECU 30 calculates the difference between the current engine speed NE and the target engine speed tNE as the engine speed deviation dNE. In step 140, the ECU 30 reads the alternator load aLD.

  In step 150, the ECU 30 calculates an ISC increase EGS. Here, the ECU 30 refers to the function data (two-dimensional map) as shown in FIG. 3 based on the calculated engine speed deviation dNE and the read alternator load aLD, thereby increasing the ISC increase EGS. Is calculated. In the two-dimensional map of FIG. 3, the ISC increase EGS increases as the engine speed deviation dNE increases to the minus side, and the ISC increase EGS increases as the alternator load aLD increases. Is set.

  In step 160, the ECU 30 increases the ISC flow rate EGC by the amount of the ISC increase EGS calculated this time. The ISC flow rate EGC is set as a value corresponding to the opening of the ISC valve 12. Then, the ECU 30 controls the actual ISC flow rate in the bypass passage 11 by controlling the opening degree of the ISC valve 12 based on the increased ISC flow rate EGC. With this ISC flow rate control, the output of the engine 1 is slightly increased when the load of the engine 1 increases due to forced charging of the battery 14 during deceleration.

  Then, in step 170, the ECU 30 determines whether or not to return from the deceleration operation or whether the engine speed NE is higher than a value obtained by adding the set value α to the target engine speed tNE. When the determination result is negative, the ECU 30 returns the process to step 130 and repeats the process from step 130.

  On the other hand, if the determination result in step 170 is affirmative, in step 180, the ECU 30 ends the increase in the ISC flow rate EGC by the ISC increase EGS. Then, the ECU 30 returns the actual ISC flow rate to the normal flow rate by controlling the opening degree of the ISC valve 12 based on the ISC flow rate EGS.

  In addition, even when the determination results of steps 100 to 120 are negative, the ECU 30 controls the opening of the ISC valve 12 based on the ISC flow rate EGC that is not increased by the ISC increase EGS in step 180, thereby Keep ISC flow at normal flow.

  Here, FIG. 4 shows a behavior of various parameters related to the charge control by a time chart. When the throttle opening degree TA increases at time t1 to t2, the engine speed NE increases and the vehicle speed SPD increases. At this time, since the engine load eLD increases, the alternator load aLD is lowered, and the charging voltage cVO is also lowered.

  Thereafter, when the throttle opening degree TA is kept constant at times t2 to t3, the engine speed NE is kept constant, and the vehicle speed SPD is also kept substantially constant. During this time, the engine load eLD, the alternator load aLD, and the charging voltage cVO are also kept constant.

  Thereafter, when the throttle opening degree TA is fully closed at time t3, the engine speed NE starts to decrease and the vehicle speed SPD also starts to decrease. At this time, since the engine load eLD starts to decrease, the alternator load aLD is increased and the charging voltage cVO is also increased. At this time, the engine 1 performs fuel cut (F / C) during deceleration operation.

  At time t4, when the engine speed NE becomes equal to or less than the value obtained by adding the set value α to the target engine speed tNE, the ISC flow rate EGC increases at that timing, and the fuel cut (F / C) ends.

  Thereafter, when the vehicle 40 stops at time t5 (when the vehicle speed SPD becomes zero), the increase in the ISC flow rate EGC ends, the alternator load aLD is lowered, and the charging voltage cVO is lowered. Here, when the engine 1 is decelerated, the ISC flow rate EGC is increased at times t4 to t5. Therefore, when the actual ISC flow rate increases and the load on the engine 1 increases, the output of the engine 1 is slightly increased. Yes. For this reason, in the conventional example, as shown by the broken lines in FIGS. 4A and 4H, the engine load eLD fluctuates rapidly and the engine rotation speed NE drops sharply. As indicated by solid lines in FIGS. 4A and 4H, both the engine load eLD and the engine rotational speed NE are smoothly reduced.

  According to the configuration of this embodiment described above, when the vehicle 40 is decelerated (when the engine 1 is decelerated), the power generation voltage of the alternator 13 is increased to generate power, and the power is forcibly charged to the battery 14. The At this time, the engine load eLD is increased by increasing the power generation voltage of the alternator 13, but when the engine load eLD is increased by this forced charging, the ISC valve 12 adjusts the ISC flow rate of the bypass passage 11 and the engine 1 The output of is slightly increased. Therefore, even if the vehicle 40 stops after the engine 1 is decelerated, a rapid decrease in the rotation of the engine 1 can be suppressed. For this reason, engine stall can be prevented in advance, the engine 1 can be prevented from being vibrated due to a sudden decrease in the rotation of the engine 1, and the drivability of the vehicle 40 can be kept good.

  In particular, in this embodiment, when the engine 1 is decelerated, the increase amount of the alternator load aLD is increased by the increase amount of the ISC flow rate EGC (ISC increase EGS). Can prevent a decrease in rotation. Further, by suppressing the rapid rotation reduction of the engine 1, the battery 14 can be forcibly charged until the vehicle speed SPD becomes “0”. Further, even when the vehicle 40 is suddenly braked, the alternator 13 can forcibly induct the battery 14, and the battery can be prevented from running out.

  In addition, this invention is not limited to the said embodiment, It can implement as follows by changing a part of structure suitably in the range which does not deviate from the meaning of invention.

  In the above-described embodiment, the output of the engine 1 is slightly increased when the engine load eLD increases due to forced charging, and the output adjusting means is configured by the bypass passage 11, the ISC valve 12, and the ECU 30. On the other hand, the output adjusting means may be constituted by elements other than the bypass passage 11, the ISC valve 12, and the ISC valve 12. Here, for example, an electronic throttle device in which a throttle valve is driven by a motor can be used as the intake air adjusting means constituting the output adjusting means. Even in this configuration, it is possible to obtain the same effect as that of the above embodiment.

The schematic block diagram which shows an engine system. The flowchart which shows a charge control routine. A two-dimensional map showing function data. A time chart showing the behavior of various parameters.

Explanation of symbols

1 Engine 2 Intake passage 5 Throttle valve 11 Bypass passage (output adjustment means, intake adjustment means)
12 ISC valve (output adjustment means, intake air adjustment means)
13 Alternator 14 Battery 30 ECU (electronic control unit, control means)
40 vehicles

Claims (3)

A vehicle charge control device provided in a vehicle equipped with an engine,
An alternator driven by the engine;
A battery for charging electric power generated by the alternator, and charging the vehicle to control charging the electric power generated by the alternator by forcibly charging the electric power generated by the alternator when the vehicle decelerates. In the device
A vehicle charge control device comprising output adjusting means for slightly increasing the output of the engine when the load of the engine increases due to the forced charging. 2. The vehicle according to claim 1, wherein the output adjustment unit includes an intake adjustment unit provided in an intake passage of the engine, and a control unit that drives and controls the intake adjustment unit in accordance with the forced charging. Charge control device. The output adjusting means forces the bypass passage provided in the intake passage of the engine to bypass the throttle valve, the idle speed control valve provided in the bypass passage, and the idle speed control valve to the forced passage. The vehicle charging control device according to claim 1, further comprising an electronic control device that controls opening and closing in accordance with charging.

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