JP6304051B2 - Hybrid car - Google Patents

Description

  The present invention relates to a hybrid vehicle, and more particularly, to a hybrid vehicle including an engine, a motor, and learning means for learning a characteristic of an intake air amount with respect to a throttle opening.

  Conventionally, in this type of hybrid vehicle, when a racing operation is detected by an accelerator opening sensor, the ignition timing is feedback-controlled based on the engine speed, so that it smoothly follows a preset speed transition line. Has been proposed (see, for example, Patent Document 1). In this vehicle, when the engine speed is increased and then decreased by the racing operation, when the engine speed becomes the target idle speed plus the predetermined speed, the ignition timing feedback control is performed. To start.

JP 2008-57402 A

  In engines mounted on automobiles, the characteristics of the intake air volume with respect to the throttle opening (hereinafter referred to as the throttle flow characteristics) change due to deposits (foreign matter adhesion), etc., so the throttle flow characteristics are learned and used for idling control, etc. It has been. If a change that affects the throttle flow rate characteristics such as deposit separation occurs, the throttle flow rate characteristics will become inappropriate.Therefore, during idling control, the engine speed increases due to an increase in the intake air amount and the subsequent fuel cut occurs. Sometimes it happens. In such a case, if the fuel cut is performed multiple times during idling control, the throttle flow rate characteristic is not appropriate and the flow rate characteristic is returned to the initial characteristic, or an intermediate characteristic between the initial characteristic and the current characteristic. Reflection processing is performed such as returning to, or returning to a value before a certain period. On the other hand, in the hybrid vehicle, the idling speed of the engine may differ depending on the state of the vehicle, and a racing operation may occur during idling control, and fuel cut may be performed. In this case, when the fuel flow is cut a plurality of times even though the throttle flow rate characteristic is appropriate, a reflection process is performed, resulting in an inappropriate throttle flow characteristic.

  The main purpose of the hybrid vehicle of the present invention is to avoid execution of unnecessary reflection processing and to maintain a more appropriate throttle flow rate characteristic.

  The hybrid vehicle of the present invention employs the following means in order to achieve the main object described above.

The hybrid vehicle of the present invention
Throttle flow rate characteristic learning for learning the characteristics of the intake air amount with respect to the engine, the motor, and the throttle opening, and the throttle flow rate when a plurality of fuel cuts are performed during idling control of the engine In a hybrid vehicle comprising learning means for performing reflection processing for characteristic learning,
The learning means does not execute the reflection process even if fuel cut is performed when a racing operation is detected during idling control of the engine.
It is characterized by that.

  In the hybrid vehicle of the present invention, when the racing operation is detected during the idling control of the engine, the reflection process is not executed even if the fuel cut is performed. As a result, unnecessary reflection processing can be avoided and more appropriate throttle flow rate characteristics can be maintained. Here, as the “reflection process”, a process for setting the throttle flow rate characteristic as an initial characteristic (initial value), a process for obtaining a characteristic obtained by dividing the current characteristic and the initial characteristic by a predetermined ratio, For example, a process having a characteristic before a predetermined period can be given.

  In such a hybrid vehicle of the present invention, the learning means includes a counter that counts up when a fuel cut is performed during idling control of the engine, and during idling control of the engine. When the racing operation is detected, the counter may not be counted up even if fuel cut is performed. Further, the learning means has a counter that counts up when a fuel cut is performed during idling control of the engine, and detects a racing operation during idling control of the engine. Sometimes the counter may be reset.

1 is a configuration diagram showing an outline of a configuration of a hybrid vehicle 20 according to an embodiment of the present invention. 2 is a configuration diagram showing an outline of the configuration of an engine 22. FIG. 5 is a flowchart showing an example of idling control processing executed by an engine ECU 24.

  Next, the form for implementing this invention is demonstrated using an Example.

  FIG. 1 is a configuration diagram showing an outline of the configuration of a hybrid vehicle 20 as an embodiment of the present invention. As shown in the figure, the hybrid vehicle 20 of the embodiment includes an engine 22, an engine electronic control unit (hereinafter referred to as an engine ECU) 24 that performs fuel injection control, ignition control, intake air amount adjustment control, and the like of the engine 22, Is provided. Further, in the hybrid vehicle 20 of the embodiment, a carrier is connected to a crankshaft 26 as an output shaft of the engine 22, and a ring gear is connected to a drive shaft 32 that is connected to drive wheels 63a and 63b via a differential gear 62. The planetary gear 30 is provided. For example, a rotor of a motor MG1 configured as a synchronous generator motor is connected to the sun gear of the planetary gear 30. For example, a rotor of a motor MG2 configured as a synchronous generator motor is connected to the drive shaft 32. The motors MG1 and MG2 are driven by inverters 41 and 42, and are driven and controlled by switching control of switching elements (not shown) of the inverters 41 and 42 by a motor electronic control unit (hereinafter referred to as a motor ECU) 40. . Motors MG1 and MG2 exchange power with battery 50 configured as, for example, a lithium ion secondary battery via inverters 41 and 42. The battery 50 is managed by a battery electronic control unit (hereinafter referred to as a battery ECU) 52 using the battery voltage Vb, the battery current Ib, the battery temperature Tb, and the like. The hybrid vehicle 20 further includes a hybrid electronic control unit (hereinafter referred to as HVECU) 70 that communicates with the engine ECU 24, the motor ECU 40, and the battery ECU 52 to control the entire vehicle.

  The engine 22 is configured as an internal combustion engine that outputs power using a hydrocarbon fuel such as gasoline or light oil. As shown in FIG. 2, the engine 22 sucks air purified by the air cleaner 122 through the throttle valve 124 and injects gasoline from the fuel injection valve 126 to mix the sucked air and gasoline. The air-fuel mixture is drawn into the combustion chamber via the intake valve 128. The sucked air-fuel mixture is exploded and burned by an electric spark from the spark plug 130, and the engine 22 converts the reciprocating motion of the piston 132 pushed down by the energy into the rotational motion of the crankshaft 26. The exhaust from the engine 22 is discharged to the outside air through a purification device 134 having a purification catalyst (three-way catalyst) that purifies harmful components such as carbon monoxide (CO), hydrocarbons (HC), and nitrogen oxides (NOx). Is done. Exhaust gas is not only discharged to the outside air but also supplied to the intake side via an exhaust gas recirculation device (hereinafter referred to as an “EGR (Exhaust Gas Recirculation) system”) 160 that recirculates the exhaust gas to the intake air. The EGR system 160 includes an EGR pipe 162 that is connected to the rear stage of the purification device 134 and supplies exhaust gas to a surge tank on the intake side, and an EGR valve 164 that is disposed in the EGR pipe 162 and is driven by a stepping motor 163. Then, by adjusting the opening degree of the EGR valve 164, the recirculation amount of the exhaust gas as the non-combustion gas is adjusted to recirculate to the intake side. In this way, the engine 22 can suck a mixture of air, exhaust, and gasoline into the combustion chamber.

  The engine ECU 24 is configured as a microprocessor centered on the CPU 24a, and includes a ROM 24b that stores a processing program, a RAM 24c that temporarily stores data, an input / output port and a communication port (not shown), in addition to the CPU 24a. . Signals from various sensors that detect the state of the engine 22 are input to the engine ECU 24 via an input port. The signals from the various sensors include the crank position from the crank position sensor 140 that detects the rotational position of the crankshaft 26, the cooling water temperature Tw from the water temperature sensor 142 that detects the temperature of the cooling water in the engine 22, and the suction to the combustion chamber. The cam position from the cam position sensor 144 that detects the rotational position of the intake valve 128 that performs exhaust and the camshaft that opens and closes the exhaust valve, the throttle opening TH from the throttle valve position sensor 146 that detects the position of the throttle valve 124, and the intake air The intake air amount Qa from the air flow meter 148 attached to the pipe, the intake air temperature Ta from the temperature sensor 149 attached to the intake pipe, the intake pressure Pin from the intake pressure sensor 158 that detects the pressure in the intake pipe, the purification device 134 Temperature attached to Catalyst temperature Tc from the sensor 134a, air-fuel ratio AF from the air-fuel ratio sensor 135a, oxygen signal O2 from the oxygen sensor 135b, knock from the knock sensor 159 that is attached to the cylinder block and detects vibration caused by the occurrence of knocking. Examples thereof include a signal Ks, an EGR valve opening degree EV from an EGR valve opening degree sensor 165 that detects the opening degree of the EGR valve 164, and the like. Further, various control signals for driving the engine 22 are output from the engine ECU 24 via an output port. Various control signals include a drive signal to the fuel injection valve 126, a drive signal to the throttle motor 136 that adjusts the position of the throttle valve 124, a control signal to the ignition coil 138 integrated with the igniter, and the intake valve 128. Examples include a control signal to the variable valve timing mechanism 150 that can change the opening / closing timing, a drive signal to the stepping motor 163 that adjusts the opening degree of the EGR valve 164, and the like. The engine ECU 24 is in communication with the hybrid electronic control unit 70, controls the operation of the engine 22 by a control signal from the hybrid electronic control unit 70, and outputs data related to the operation state of the engine 22 as necessary. The engine ECU 24 calculates the rotational speed of the crankshaft 26, that is, the rotational speed Ne of the engine 22 based on the crank position from the crank position sensor 140, and calculates the intake air amount Qa from the air flow meter 148. Further, the engine ECU 24 learns the characteristic (throttle flow characteristic) of the intake air amount Qa with respect to the throttle opening TH.

  Although not shown, the motor ECU 40 is configured as a microprocessor centered on a CPU, and includes a ROM for storing a processing program, a RAM for temporarily storing data, an input / output port, and a communication port in addition to the CPU. . The motor ECU 40 receives signals necessary for driving and controlling the motors MG1 and MG2, such as rotational positions θm1 and θm2 from a rotational position detection sensor for detecting the rotational position of the rotor of the motors MG1 and MG2, and a current sensor (not shown). The detected phase current applied to the motors MG1 and MG2 is input via the input port. From the motor ECU 40, switching control signals and the like to the inverters 41 and 42 are output via an output port. The motor ECU 40 is in communication with the HVECU 70, controls the driving of the motors MG1 and MG2 by a control signal from the HVECU 70, and outputs data related to the operating state of the motors MG1 and MG2 to the HVECU 70 as necessary. The motor ECU 40 also calculates the rotational speeds Nm1 and Nm2 of the motors MG1 and MG2 based on the rotational positions θm1 and θm2 of the rotors of the motors MG1 and MG2 from the rotational position detection sensor.

  Although not shown, the battery ECU 52 is configured as a microprocessor centered on a CPU, and includes a ROM for storing a processing program, a RAM for temporarily storing data, an input / output port, and a communication port in addition to the CPU. . The battery ECU 52 is attached to a signal necessary for managing the battery 50, for example, a battery voltage Vb from a voltage sensor (not shown) installed between the terminals of the battery 50 or a power line connected to the output terminal of the battery 50. The battery current Ib from the current sensor (not shown) and the battery temperature Tb from the temperature sensor (not shown) attached to the battery 50 are input. From the battery ECU 52, data relating to the state of the battery 50 is transmitted to the HVECU 70 by communication as necessary. Further, in order to manage the battery 50, the battery ECU 52 is based on the integrated value of the battery current Ib detected by the current sensor, and is a power storage ratio that is a ratio of the capacity of power that can be discharged from the battery 50 at that time to the total capacity. The SOC is calculated, and the input / output limits Win and Wout, which are the maximum allowable power that may charge / discharge the battery 50, are calculated based on the calculated storage ratio SOC and the battery temperature Tb.

  Although not shown, the HVECU 70 is configured as a microprocessor centered on a CPU. In addition to the CPU, a ROM that stores processing programs, a RAM that temporarily stores data, and a nonvolatile flash that holds the stored data Equipped with memory, input / output port and communication port. The HVECU 70 includes an ignition signal from the ignition switch 80, a shift position SP from the shift position sensor 82 that detects the operation position of the shift lever 81, and an accelerator opening degree from the accelerator pedal position sensor 84 that detects the amount of depression of the accelerator pedal 83. Acc, the brake pedal position BP from the brake pedal position sensor 86 that detects the depression amount of the brake pedal 85, the vehicle speed V from the vehicle speed sensor 88, and the like are input via the input port. As described above, the HVECU 70 is connected to the engine ECU 24, the motor ECU 40, and the battery ECU 52 via the communication port, and exchanges various control signals and data with the engine ECU 24, the motor ECU 40, and the battery ECU 52.

  Next, the operation in the hybrid vehicle 20 of the embodiment configured as described above, particularly the operation during idling control of the engine 22 will be described. FIG. 3 is a flowchart showing an example of idling control time processing executed by the engine ECU 24. This process is repeatedly executed while the engine 22 is under idling control.

  When the idling control process is executed, the engine ECU 24 first determines whether or not a fuel cut has been performed (step S100). Here, the fuel cut during the idling control is performed when the catalyst warm-up suppression control (control to continue the explosion combustion of the engine 22) is not performed and the rotation speed Ne of the engine 22 is a predetermined rotation to the target rotation speed Ne *. This is executed when the rotation speed is greater than the number Nref plus (Ne * + Nref). When the fuel cut is not performed, this process is terminated.

  On the other hand, when a fuel cut is performed during idling control, it is determined whether or not a racing operation has been detected (step S110). Here, the racing operation refers to an operation of increasing the rotational speed Ne of the engine 22 by increasing the throttle opening while the engine 22 is not loaded. When the racing operation is detected, the counter C is held (step S120), and when the racing operation is not detected, the counter C is incremented by 1 (step S130). Then, it is determined whether or not the counter C is greater than or equal to the threshold value Cref (step S140). When the counter C is less than the threshold value Cref, this process ends. On the other hand, when the counter C is equal to or greater than the threshold value Cref, a reflection process is performed on the throttle flow rate characteristic (step S150), and this process ends. Here, the threshold value Cref may be 3 or 4 as a value. The reason why the reflection processing is performed after the counter C becomes equal to or greater than the threshold value Cref is to increase the certainty in determining that the fuel cut has been performed because the throttle flow rate characteristic is not appropriate. The reflection process includes a process for setting the throttle flow rate characteristic as an initial characteristic (initial value), a process for obtaining a characteristic obtained by dividing the current characteristic and the initial characteristic by a predetermined ratio, A process having the above characteristics can be used. The counter C is held when the racing operation is detected when the fuel cut is performed. In the case of the hybrid vehicle 20, the fuel cut is performed during the idling control of the engine 22 even if the throttle flow rate characteristic is appropriate. It is because it may be performed. In the hybrid vehicle 20, the idling speed of the engine 22 may vary depending on the state of the vehicle. When the idling speed is changed, a racing operation is performed during idling control, and fuel cut may be performed. If the fuel cut in this case is counted by the counter C, the reflection process of the throttle flow rate characteristic is performed even though the throttle flow rate characteristic is appropriate. In the idling control process of the embodiment, even if the fuel cut is performed during the idling control, the counter C is held when the racing operation is detected, thereby preventing the reflection process of the throttle flow characteristic from being erroneously performed. -ing

  In the hybrid vehicle 20 of the embodiment described above, the counter C is held when the racing operation is detected when the fuel cut is performed during the idling control of the engine 22. As a result, it is possible to prevent erroneous reflection processing of the throttle flow characteristic, and to maintain a more appropriate throttle flow characteristic. Of course, when the racing operation is not detected when the fuel cut is performed during the idling control of the engine 22, the counter C is incremented by the value 1, and when the counter C reaches the threshold value Cref or more, the reflection processing of the throttle flow rate characteristic is performed. Do. Thereby, the throttle flow rate characteristic can be made more appropriate.

  In the hybrid vehicle 20 of the embodiment, the counter C is held when the racing operation is detected when the fuel cut is performed during the idling control of the engine 22. However, the counter C may be reset to 0 when a racing operation is detected when a fuel cut is performed during idling control of the engine 22.

  As mentioned above, although the form for implementing this invention was demonstrated using the Example, this invention is not limited at all to such an Example, In the range which does not deviate from the summary of this invention, it is with various forms. Of course, it can be implemented.

  The present invention can be used in the manufacturing industry of hybrid vehicles.

  20 hybrid vehicle, 22 engine, 24 engine electronic control unit (engine ECU), 24a CPU, 24b ROM, 24c RAM, 26 crankshaft, 30 planetary gear, 32 drive shaft, 40 motor electronic control unit (motor ECU), 41 , 42 inverter, 50 battery, 52 battery electronic control unit (battery ECU), 62 differential gear, 63a, 63b driving wheel, 64a, 64b wheel, 70 hybrid electronic control unit (HV ECU), 80 ignition switch, 81 shift lever , 82 Shift position sensor, 83 Accelerator pedal, 84 Accelerator pedal position sensor, 85 Brake pedal, 86 Brake pedal position sensor, 88 Vehicle speed sensor 122 Air cleaner, 124 Throttle valve, 126 Fuel injection valve, 128 Intake valve, 130 Spark plug, 132 Piston, 134 Purifier, 134a Temperature sensor, 135a Air-fuel ratio sensor, 135b Oxygen sensor, 136 Throttle motor, 138 Ignition coil, 140 Crank position sensor, 142 Water temperature sensor, 144 Cam position sensor, 146 Throttle valve position sensor, 148 Air flow meter, 149 Temperature sensor, 150 Variable valve timing mechanism, 158 Intake pressure sensor, 159 Knock sensor, 160 EGR system, 162 EGR pipe, 163 Stepping motor, 164 EGR valve, 165 EGR valve opening sensor, MG1, MG2 motor.

Claims (1)

Throttle flow rate characteristic learning for learning the characteristics of the intake air amount with respect to the engine, the motor, and the throttle opening, and the throttle flow rate when a plurality of fuel cuts are performed during idling control of the engine In a hybrid vehicle comprising learning means for performing reflection processing for characteristic learning,
The learning means does not execute the reflection process even if fuel cut is performed when a racing operation is detected during idling control of the engine.
A hybrid vehicle characterized by that.

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