JP2009137350A - Power output device for vehicle and its control method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a power output device for a vehicle achieving stable control even when adopting a supercharged engine. <P>SOLUTION: The power output device for a vehicle is provided with a control device configured of an HV-ECU 70, a motor ECU 40 and an engine ECU 24. The power output device estimates the output torque of an engine 22 by processing different according to whether the quantity of a change in the opening degree of a throttle valve is larger or smaller than a threshold, and controls a motor generator MG1 so as to output a required driving force to a drive shaft. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a vehicle power output apparatus and a control method therefor, and more particularly to a power output apparatus for a hybrid vehicle that obtains vehicle propulsion power from an internal combustion engine and a rotating electrical machine and a control method therefor.

  In recent years, the issue of global warming has attracted attention, and the production of environmentally friendly hybrid vehicles is increasing. Some hybrid vehicles have a sun gear, a carrier, and a ring gear of a planetary gear mechanism connected to an engine output shaft, a first motor rotating shaft, and a driving shaft, and a driving motor connected to a second motor via a reduction gear. Proposed.

In such vehicle engine speed control, Japanese Patent Application Laid-Open No. 2006-63865 (Patent Document 1) discloses setting a target torque of a first motor using an engine estimated torque in consideration of an engine response speed. Yes.
JP 2006-63865 A JP 2003-326992 A

  When a supercharged engine is adopted, a response delay of the intake pipe pressure occurs, and the engine torque may continue to be output even when the amount of change in the throttle valve is large. At that time, the first motor is controlled based on an accelerator signal or the like in order to control the engine rotation to the target value. However, the first motor absorbs the engine torque due to the delay of the change in the engine torque. There may be a case where the burden on the rotating electric machine becomes excessive.

  An object of the present invention is to provide a vehicle power output device that can be stably controlled even when a supercharged engine is employed.

  In summary, the present invention is a power output apparatus for a vehicle, and includes an internal combustion engine including an air flow meter, a supercharger, and a throttle valve in an intake path, a first rotating electrical machine, an internal combustion engine, and a first rotating electrical machine. And the output torque of the internal combustion engine by different processing depending on whether the drive shaft for driving the wheel is connected to the three input shafts, and when the amount of change in the opening of the throttle valve is larger or smaller than the threshold value And a control device that controls the first rotating electrical machine to output the required driving force to the drive shaft.

  Preferably, the control device sets first and second constants for estimating a delay in change of the output torque with respect to a target torque of the internal combustion engine, and the internal combustion engine is based on one of the first and second constants. Estimate the engine output torque response delay. The first constant is a constant applied when the amount of change in the opening of the throttle valve is smaller than the threshold value. The second constant is a constant applied when the amount of change in the opening of the throttle valve is larger than the threshold value.

More preferably, the control device sets the second constant according to the load factor of the internal combustion engine.
More preferably, the control device stores an air amount measured by an air flow meter. When the control device calculates the second constant, it passes through the supercharger based on the air amount before the throttle valve opening change exceeding the threshold, the load factor, and the rotational speed of the internal combustion engine. An air amount difference from the air amount after the change in the opening degree after correcting the delay in the later change in the intake air amount is calculated. Then, the control device sets the second constant based on the air amount difference.

  Preferably, the vehicle power device further includes a second rotating electrical machine that transmits and receives mechanical power to and from the drive shaft through a transmission path different from the power split mechanism. The first rotating electrical machine mainly operates as a generator, and the second rotating electrical machine mainly operates as an electric motor.

  In another aspect, the present invention provides an internal combustion engine including an air flow meter, a supercharger, and a throttle valve in an intake path, a first rotating electrical machine, an internal combustion engine, a first rotating electrical machine, and a drive for driving wheels. A method of controlling a vehicle power output device including a power split mechanism in which a shaft is connected to three input shafts, wherein the amount of change in the opening degree of the throttle valve is different depending on whether it is larger or smaller than a threshold value To estimate the output torque of the internal combustion engine and to control the first rotating electrical machine to output the required driving force to the drive shaft.

  Preferably, the step of estimating the output torque includes a step of setting a first constant for estimating a delay in the change of the output torque with respect to the target torque of the internal combustion engine, and a delay in the change of the output torque with respect to the target torque of the internal combustion engine. Setting a second constant for estimating the output torque, and estimating a response delay of the output torque of the internal combustion engine based on one of the first and second constants. The first constant is a constant applied when the amount of change in the opening of the throttle valve is smaller than the threshold value. The second constant is a constant applied when the amount of change in the opening of the throttle valve is larger than the threshold value.

  More preferably, the step of setting the second constant sets the second constant according to the load factor of the internal combustion engine.

  More preferably, in the step of setting the second constant, the amount of air measured by the air flow meter is stored, and when calculating the second constant, the air before the throttle valve opening change exceeding the threshold value is calculated. The air volume difference is calculated by calculating the air volume difference between the air volume and the air flow after changing the opening, which compensates for the delay in the intake air volume change after passing through the turbocharger based on the load factor and the rotational speed of the internal combustion engine. A second constant is set based on

  Preferably, the vehicle power device further includes a second rotating electrical machine that transmits and receives mechanical power to and from the drive shaft through a transmission path different from the power split mechanism. The first rotating electrical machine mainly operates as a generator, and the second rotating electrical machine mainly operates as an electric motor.

  ADVANTAGE OF THE INVENTION According to this invention, the hybrid vehicle which can be stably controlled by the structure which employ | adopted the supercharged engine is realizable.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals and description thereof will not be repeated.

  FIG. 1 is a schematic diagram of a configuration of a hybrid vehicle 20 equipped with an internal combustion engine as an embodiment of the present invention.

  Referring to FIG. 1, hybrid vehicle 20 includes an engine 22, a three-shaft power split mechanism 30 connected to crankshaft 26 that is an output shaft of engine 22 via damper 28, and power split mechanism 30. Motor generator MG1 connected to generate power, reduction gear 35 attached to ring gear shaft 32a as a drive shaft connected to power split mechanism 30, motor generator MG2 connected to reduction gear 35, and power output device A hybrid electronic control unit 70 (hereinafter referred to as HV-ECU 70) for controlling the whole is provided.

  The engine 22 is an internal combustion engine that outputs power using a hydrocarbon-based fuel such as gasoline or light oil, and an engine electronic control unit 24 (hereinafter referred to as an engine ECU 24) that receives signals from various sensors that detect the operating state of the engine 22. The operation control such as the fuel injection control, the ignition control, and the intake air amount adjustment control is performed. The engine ECU 24 communicates with the HV-ECU 70, controls the operation of the engine 22 based on a control signal from the HV-ECU 70, and outputs data related to the operating state of the engine 22 to the HV-ECU 70 as necessary.

  The power split mechanism 30 includes an external gear sun gear 31, an internal gear ring gear 32 arranged concentrically with the sun gear 31, a plurality of pinion gears 33 that mesh with the sun gear 31 and mesh with the ring gear 32, And a carrier 34 for holding the pinion gear 33 so as to rotate and revolve freely. The power split mechanism 30 is configured as a planetary gear mechanism that performs a differential action with the sun gear 31, the ring gear 32, and the carrier 34 as rotational elements.

  Assuming that the rotational speed Ns of the sun gear 31, the rotational speed Nr of the ring gear 32, and the rotational speed Nc of the carrier 34, the relationship of the collinear charts described in FIG. 7 and FIG. The relationship of the above formulas (1) and (2) is also established.

  A crankshaft 26 of the engine 22 is connected to the carrier 34, a motor generator MG1 is connected to the sun gear 31, and a reduction gear 35 is connected to the ring gear 32 via a ring gear shaft 32a. Therefore, assuming that the engine speed Ne, the motor generator MG1 speed Nm1, and the motor generator MG2 speed Nm2, the relationship Ns = Nm1, Nc = Ne, Nr = k · Nm2 holds. Here, k is a reduction ratio of the reduction gear 35.

  When motor generator MG1 functions as a generator, power from engine 22 input from carrier 34 is distributed to sun gear 31 side and ring gear 32 side according to the gear ratio. When motor generator MG1 functions as an electric motor, the power from engine 22 input from carrier 34 and the power from motor generator MG1 input from sun gear 31 are integrated and output to ring gear 32 side. The power output to the ring gear 32 is finally output from the ring gear shaft 32a to the drive wheels 63a and 63b of the vehicle via the gear mechanism 60 and the differential gear 62.

  Motor generator MG1 and motor generator MG2 are both synchronous generator motors that can be driven as generators and motors, and exchange power with battery 50 through inverters 41 and 42.

  The power line 54 connecting the inverters 41 and 42 and the battery 50 includes a positive electrode bus and a negative electrode bus shared by the inverters 41 and 42. As a result, the electric power generated by either motor generator MG1 or MG2 can be consumed by another motor. Therefore, battery 50 is charged / discharged by electric power generated from one of motor generators MG1 and MG2 or insufficient electric power.

  Note that the battery 50 is not charged / discharged if the power balance is balanced by the motor generators MG1, MG2.

  Motor generators MG1, MG2 are both driven and controlled by a motor electronic control unit (hereinafter referred to as motor ECU) 40. The motor ECU 40 includes signals necessary for driving and controlling the motor generators MG1 and MG2, such as signals from rotational position detection sensors 43 and 44 that detect the rotational positions of the rotors of the motor generators MG1 and MG2, and current sensors (not shown). The phase current applied to the motor generators MG1 and MG2 detected by the above is input.

  The motor ECU 40 outputs a switching control signal to the inverters 41 and 42. The motor ECU 40 communicates with the HV-ECU 70, controls the drive of the motor generators MG1 and MG2 by a control signal from the HV-ECU 70, and transmits data related to the operation state of the motor generators MG1 and MG2 to the HV-ECU 70 as necessary. Output.

  The battery 50 is managed by a battery electronic control unit 52 (hereinafter referred to as a battery ECU 52). The battery ECU 52 receives signals necessary for managing the battery 50, for example, a voltage between terminals from a voltage sensor (not shown) installed between terminals of the battery 50, and a power line 54 connected to the output terminal of the battery 50. The charging / discharging current from the attached current sensor (not shown), the battery temperature Tb from the temperature sensor 51 attached to the battery 50, and the like are input, and the HV-ECU 70 communicates data regarding the state of the battery 50 as necessary. Output to. The battery ECU 52 also calculates the remaining capacity (SOC) based on the integrated value of the charge / discharge current detected by the current sensor in order to manage the battery 50.

  The HV-ECU 70 is configured around the CPU 72. In addition to the CPU 72, the HV-ECU 70 includes a ROM 74 that stores processing programs and maps, a RAM 76 that temporarily stores data, and input / output ports and communication ports (not shown).

  The HV-ECU 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 from the accelerator pedal position sensor 84 that detects the amount of depression of the accelerator pedal 83. The opening degree Acc, the brake pedal position BP from the brake pedal position sensor 86 for detecting 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 HV-ECU 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.

  The hybrid vehicle 20 calculates the required torque to be output to the ring gear shaft 32a as the drive shaft based on the accelerator opening Acc and the vehicle speed V corresponding to the depression amount of the accelerator pedal 83 by the driver. The operation of the engine 22, the motor generator MG1, and the motor generator MG2 is controlled so that the required power corresponding to this required torque is output to the ring gear shaft 32a.

  As operation control of the engine 22, the motor generator MG1, and the motor generator MG2, there are a torque conversion operation mode, a charge / discharge operation mode, a motor operation mode, and the like.

  In the torque conversion operation mode, the HV-ECU 70 controls the operation of the engine 22 so that power corresponding to the required power is output from the engine 22, and all of the power output from the engine 22 is transmitted to the power split mechanism 30 and the motor generator. Motor generator MG1 and motor generator MG2 are driven and controlled so that torque is converted by MG1 and motor generator MG2 and output to ring gear shaft 32a.

  In the charge / discharge operation mode, the HV-ECU 70 controls the operation of the engine 22 so that the power corresponding to the sum of the required power and the power required for charging / discharging the battery 50 is output from the engine 22, All or part of the motive power output from the engine 22 with the discharge is output to the ring gear shaft 32a with the torque conversion by the power split mechanism 30, the motor generator MG1, and the motor generator MG2. Motor generator MG1 and motor generator MG2 are driven and controlled.

  In the motor operation mode, the HV-ECU 70 drives and controls the motor generator MG1 and the motor generator MG2 so as to stop the operation of the engine 22 and output power corresponding to the required power from the motor generator MG2 to the ring gear shaft 32a.

  In FIG. 1, the control unit for power output is realized by the HV-ECU 70, the motor ECU 40, the battery ECU 52, and the engine ECU 24. However, these ECUs may be combined into a smaller number of ECUs. You may make it implement | achieve with many ECU of the more fragmented function.

  FIG. 2 is a diagram showing in detail a configuration related to engine 22 of hybrid vehicle 20 shown in FIG.

  Referring to FIG. 2, vehicle 20 includes an engine 22, a supercharger 200, an intercooler 162, and an engine ECU 24.

  Air sucked from the suction port 150 is filtered by the air cleaner 152. The air filtered by the air cleaner 152 flows toward the supercharger 200 through the intake passage 156. The air that has entered the supercharger 200 is compressed by the compressor 202, then flows through the intake passage 160, is sent to the intercooler 162, and is cooled by the intercooler 162. The air cooled by the intercooler 162 passes through the intake passage 102 and is taken into the engine 22.

  An air flow meter 154 that detects the intake air amount Q is provided in the intake passage 156. The air flow meter 154 transmits a signal representing the detected intake air amount to the engine ECU 24.

  The intercooler 162 cools the air that has been compressed by the compressor 202 and has risen in temperature. Since the volume of the cooled air is smaller than that before cooling, more air is sent to the engine 22.

  A throttle valve 166 that adjusts the flow rate of air flowing through the intake passage 102 is provided in the middle of the intake passage 102. The throttle valve 166 is driven by a throttle motor 168. Throttle motor 168 is driven in accordance with a control signal received from engine ECU 24.

  An intake pipe pressure sensor 170 and an intake air temperature sensor 172 are provided in the intake passage 102. The intake pipe pressure sensor 170 detects the pressure of air in the intake passage 102. The intake pipe pressure sensor 170 transmits a signal representing the detected air pressure to the engine ECU 24. The intake air temperature sensor 172 detects the temperature of air in the intake passage 102. Intake air temperature sensor 172 transmits a signal representing the detected air temperature to engine ECU 24.

  The engine 22 includes a cylinder head 124 and a cylinder block 112. The cylinder block 112 is provided with a plurality of cylinders, and FIG. 2 representatively shows one cylinder. A piston 114 is slidably provided in each cylinder. The piston 114 is connected to the crankshaft 26 via a connecting rod 116. A piston 114, connecting rod 116 and crankshaft 26 form a crank mechanism.

  A combustion chamber 108 is formed at the upper part of the piston 114. The combustion chamber 108 is provided with a spark plug 110. The fuel injector 106 injects fuel into the intake passage 102 of the cylinder head. In the present embodiment, the engine 22 is described as being a port injection type engine, but is not particularly limited to a port injection type engine. For example, the engine 22 may be an internal combustion engine, and may be a direct injection engine or a diesel engine.

  The cylinder head 124 is provided with an intake passage 102 and an exhaust passage 130 so as to be connected to the combustion chamber 108. An intake valve 104 is provided between the intake passage 102 and the combustion chamber 108. An exhaust valve 128 is provided between the exhaust passage 130 and the combustion chamber 108. The intake valve 104 and the exhaust valve 128 are driven by a camshaft (not shown) that rotates in conjunction with the crankshaft 26.

  The air flowing through the intake passage 102 is mixed with the fuel injected from the fuel injection injector 106. The air-fuel mixture is sucked into the combustion chamber 108 by opening the intake valve 104 when the piston 114 descends. The air-fuel mixture flowing into the combustion chamber 108 is ignited and burned by the spark plug 110 when the intake valve 104 closes and the piston 114 rises to near the top dead center. Piston 114 is pushed down by the pressure by combustion. At this time, the vertical motion of the piston 114 is converted into the rotational motion of the crankshaft 26 via the crank mechanism.

  When the piston 114 is lowered to near the bottom dead center, the exhaust valve 128 is opened. When the piston 114 rises again, the air combusted in the combustion chamber 108, that is, the exhaust gas, passes through the exhaust passage 130. The air that has entered the exhaust passage 130 is guided to the catalyst 182 through the exhaust pipe 180 after driving the turbine 204 of the supercharger 200. The exhaust gas is purified by the catalyst 182 and then discharged outside the vehicle.

  A pulley (not shown) is provided at one end of the crankshaft 26. This pulley is connected to a pulley provided on the rotating shaft of the alternator via a belt. The alternator is activated by the rotation of the crankshaft 26 to generate power.

  The timing rotor 118 is provided on the crankshaft 26 and rotates together with the crankshaft 26. A plurality of protrusions are provided on the outer periphery of the timing rotor 118 at predetermined intervals. The crank position sensor 122 is provided to face the protrusion of the timing rotor 118. When the timing rotor 118 rotates, the air gap between the projection of the timing rotor 118 and the crank position sensor 122 changes, so that the magnetic flux passing through the coil portion of the crank position sensor 122 increases and decreases, and an electromotive force is generated in the coil portion. . The crank position sensor 122 transmits a signal representing the electromotive force to the engine ECU 24. Engine ECU 24 detects the crank angle based on the signal transmitted from crank position sensor 122.

  Further, the vehicle is provided with a vehicle speed sensor (not shown) on the wheel, and detects the rotation speed (wheel speed) of the wheel. The vehicle speed sensor transmits a signal representing the detection result to the engine ECU 24. The engine ECU 24 calculates the vehicle speed from the rotational speed of the wheels.

  The engine ECU 24 stores a signal transmitted from each sensor such as an intake pressure, an intake temperature, an intake air amount, a wheel speed, a depression amount of an accelerator pedal 233 given by communication from the hybrid ECU 70 in FIG. Arithmetic processing is performed based on the map and the program, and the devices are controlled so that the engine 22 is in a desired operating state.

  The supercharger 200 includes a compressor 202, a shaft 210, and a turbine 204. A compressor wheel (also referred to as a compressor rotor, a compressor blade, etc.) 206 is accommodated in the housing of the compressor 202. The compressor wheel 206 compresses (supercharges) the air filtered by the air cleaner 152.

  A turbine wheel (also referred to as a turbine rotor, a turbine blade, or the like) 208 is accommodated in the housing of the turbine 204. The turbine wheel 208 is rotated by exhaust gas.

  The compressor wheel 206 and the turbine wheel 208 are provided at both ends of the shaft 210, respectively. That is, when the turbine wheel 208 is rotated by the exhaust gas, the compressor wheel 206 is also rotated. The shaft 210 is rotatably supported by the supercharger housing.

  In the supercharger 200 having the above-described configuration, after the air mixed with fuel is burned in the engine 22, the exhaust gas is guided into the turbine 204 from the exhaust passage 130. The exhaust gas then rotates the turbine wheel 208 and the rotational force is transmitted to the shaft 210. Thereafter, the exhaust gas flows through the exhaust pipe 180 and is guided to the catalyst 182. The exhaust gas guided to the catalyst 182 is exhausted outside the vehicle in a purified state.

  On the other hand, air taken from outside the vehicle to be supplied to the engine 22 is filtered by the air cleaner 152, then flows through the intake passage 156 and is guided into the compressor 202. The air is compressed (supercharged) by a compressor wheel 206 that rotates integrally with the shaft 210. The compressed air is guided to the intercooler 162 and is sucked into the combustion chamber 108 through the intake passage 102 of the engine 22 in a cooled state.

Next, the operation of the hybrid vehicle 20 of the embodiment thus configured will be described.
FIG. 3 is a flowchart illustrating an example of a drive control routine executed by the HV-ECU 70 of the hybrid vehicle 20 according to the embodiment. This routine is repeatedly executed every predetermined time (for example, every 8 msec).

  When the drive control routine of FIG. 3 is executed, the CPU 72 of the HV-ECU 70 first starts with the accelerator opening Acc from the accelerator pedal position sensor 84, the vehicle speed V from the vehicle speed sensor 88, the rotational speed Ne of the engine 22, the motor generator. A process of inputting data such as the rotational speeds Nm1, Nm2 of the MG1, MG2 and the charge / discharge required power Pb * of the battery 50 is executed (step S100).

  Here, the rotational speed Ne of the engine 22 is detected by the crank position sensor 122 of FIG. 2 attached to the crankshaft 26, and is input by communication via the engine ECU 24. The rotational speeds Nm1 and Nm2 of the motor generators MG1 and MG2 are calculated based on the rotational positions of the rotors of the motor generators MG1 and MG2 detected by the rotational position detection sensors 43 and 44, and are input from the motor ECU 40 by communication. Is done. The charge / discharge required power Pb * is set based on the remaining capacity SOC of the battery 50 and is input from the battery ECU 52 by communication.

  When the data is input in this way, the CPU 72 calculates the required torque Tr * to be output to the ring gear shaft 32a as the drive shaft connected to the drive wheels 63a and 63b based on the input accelerator opening Acc and the vehicle speed V. The required power Pr * is set (step S110).

FIG. 4 is a diagram illustrating an example of a map for request torque setting.
As shown in FIG. 4, the relationship among the accelerator opening Acc, the vehicle speed V, and the required torque Tr * is determined in advance. This relationship is stored in the ROM 74 as a required torque setting map, and when the accelerator opening Acc and the vehicle speed V are given, the corresponding required torque Tr * is derived from the stored map.

  The required power Pr * is set by multiplying the required torque Tr * by the rotational speed Nr of the ring gear shaft 32a. The rotation speed Nr of the ring gear shaft 32a can be obtained by multiplying the vehicle speed V by a conversion factor, or can be obtained by dividing the rotation speed Nm2 of the motor generator MG2 by the gear ratio Gr of the reduction gear 35.

  When the required power Pr * is set in this way, the engine required power Pe * to be output from the engine 22 is set by the sum of the set required power Pr *, the charge / discharge required power Pb * of the battery 50, and the loss Loss (step S120). Then, based on the set engine required power Pe *, the target rotational speed Ne * and the target torque Te * of the engine 22 are set (step S130). This setting is performed by setting the target rotational speed Ne * and the target torque Te * based on the operation line for efficiently operating the engine 22 and the engine required power Pe *.

  FIG. 5 is a diagram showing how the target rotational speed Ne * and the target torque Te * are set in an example of the operation line of the engine 22.

  As shown in FIG. 5, the target rotational speed Ne * and the target torque Te * are a curve in which the engine operation line indicated by the solid line and the engine required power Pe * (= Ne * × Te *) indicated by the broken line are constant. It can be obtained from the intersection.

  If the target rotational speed Ne * and the target torque Te * are set in step S130 of FIG. 3, then the engine estimated torque Test is set (step S140). Here, the estimated engine torque Test is estimated as torque output from the engine 22 when the engine 22 is operated at the target torque Te *. The method for setting the engine estimated torque Test will be described in detail later.

  Then, using the set target rotational speed Ne *, the rotational speed Nr (= Nm2 / Gr) of the ring gear shaft 32a, and the gear ratio ρ of the power split mechanism 30, the target rotational speed Nm1 of the motor generator MG1 is given by the following equation (1). * Calculate. Then, based on the deviation ΔNm1 between the calculated target rotational speed Nm1 * and the current rotational speed Nm1, the estimated engine torque Test set in step S140 and the gear ratio ρ of the power split mechanism 30, the motor generator is expressed by the following equation (2). A torque command Tm1 * for MG1 is calculated (step S150).

  FIG. 6 is a collinear diagram showing the dynamic relationship between the rotational speed and torque of each rotary element of the power split mechanism 30.

  In FIG. 6, the leftmost S-axis indicates the rotation speed of the sun gear 31 that is the rotation speed Nm1 of the motor generator MG1, the C-axis indicates the rotation speed of the carrier 34 that is the rotation speed Ne of the engine 22, and the R-axis indicates the ring gear 32. The rotation speed Nr of the (ring gear shaft 32a) is shown. Note that two upward bold arrows on the R-axis indicate that the torque output from the engine 22 when the engine 22 is operated with the target torque Te * and the motor generator MG1 is operated with the torque command Tm1 * is the ring gear shaft 32a. The torque Ter transmitted to the motor and the torque Tm2 * output from the motor generator MG2 acts on the ring gear shaft 32a.

The following formula (1) can be easily derived from the relationship of the rotational speed in the alignment chart of FIG. Further, the following equation (2) indicates that the feedforward term for canceling the torque transmitted from the engine 22 to the rotating shaft of the sun gear 31 and the motor generator MG1 to rotate the motor generator MG1 at the target rotation speed Nm1 *. And a feedback term for canceling the deviation ΔNm1 between the target rotational speed Nm1 * and the current rotational speed Nm1. The feedforward term is -Teest · ρ / (1 + ρ). In the remaining feedback term, “KP” in the second term on the right side is the gain of the proportional term, “KI” in the third term on the right side is the gain of the integral term, and “KD” in the fourth term on the right side is the gain of the differential term. .
Nm1 * = (Ne * ・ (1 + ρ) -Nm2 / Gr) / ρ (1)
Tm1 * =-Teest ・ ρ / (1 + ρ) + KP ・ ΔNm1 + KI∫ΔNm1dt + KD ・ d (ΔNm1) / dt (2)
In this way, target rotation speed Nm1 * and torque command Tm1 * of motor generator MG1 are calculated. Then, using the required torque Tr *, the torque command Tm1 *, the gear ratio ρ of the power split mechanism 30 and the gear ratio Gr of the reduction gear 35, the motor generator MG2 applies the required torque Tr * to the ring gear shaft 32a. Torque command Tm2 * to be output is set (step S160). Equation (3) can be derived from the relationship of torque balance on the R axis in FIG.
Tm2 * = (Tr * + Tm1 * / ρ) / Gr (3)
In this way, the target rotational speed Ne * and target torque Te * of the engine 22 and torque commands Tm1 * and Tm2 * of the motor generators MG1 and MG2 are set. Then, the target rotational speed Ne * and target torque Te * of the engine 22 are transmitted to the engine ECU 24, and the torque commands Tm1 * and Tm2 * of the motor generators MG1 and MG2 are transmitted to the motor ECU 40 (step S170). Ends (step S180).

  The engine ECU 24 that has received the target rotational speed Ne * and the target torque Te * controls the fuel injection in the engine 22 so that the engine 22 is operated at the operating point indicated by the target rotational speed Ne * and the target torque Te *. And control such as ignition control.

  The motor ECU 40 that has received the torque commands Tm1 * and Tm2 * switches the inverters 41 and 42 so that the motor generator MG1 is driven by the torque command Tm1 * and the motor generator MG2 is driven by the torque command Tm2 *. Switching control of the element is performed.

  FIG. 7 is a flowchart showing a process for setting the engine estimated torque Test in step S140 of FIG.

  In the engine estimated torque setting process of FIG. 7, first, basic dead time Td and first-order lag constant Tc are set. Here, the dead time Td and the first-order lag time constant Tc approximate the torque actually output from the engine 22 with the first-order lag when the engine 22 is operated at the target torque Te *. It is for expressing the responsiveness.

  Td = ftd (Ne) indicates that the dead time Td is determined as a function using the engine speed Ne as a variable, and can be previously set as a map.

  In this case, the relationship between the rotational speed Ne of the engine 22 and the dead time Td is obtained in advance and stored in the ROM 74 as a map, and when the engine rotational speed Ne is given, the corresponding dead time Td is derived from the map. Time Td is set.

  FIG. 8 is a diagram showing an example of a map that can be used to determine the dead time Td in step S200.

  In FIG. 8, the vertical axis represents the dead time Td, and the horizontal axis represents the engine speed Ne. As the engine speed Ne increases, the dead time Td is set smaller.

  Further, the relationship between the rotational speed Ne of the engine 22 and the first-order lag time constant Tc is obtained in advance and stored in the ROM 74 as a map. When the engine speed Ne is given, a corresponding first-order lag time constant Tc is derived from the map and set.

  FIG. 9 is a diagram showing an example of a map that can be used to determine the first-order lag time constant Tc in step S200.

  In FIG. 9, the vertical axis represents the first-order lag time constant Tc, and the horizontal axis represents the engine speed Ne. As the engine speed Ne increases, the first-order lag time constant Tc is set smaller.

  Referring to FIG. 7 again, after the standard dead time Td and first-order lag constant Tc in step S200 are determined, subsequently, whether or not the absolute value | Δθ | of the throttle change amount is larger than the threshold value θth. Is determined (step S210). If the throttle opening changes rapidly and the estimated engine torque is obtained from the dead time set in step S200 and the first-order lag constant, the torque error becomes large. The threshold value θth is a threshold value for detecting a sudden change in the throttle opening.

  When the absolute value | Δθ | of the throttle change amount is not larger than the threshold value θth (NO in step S210), it is not necessary to consider the response delay of the supercharger. Accordingly, the dead time Td and the first-order lag constant Tc determined in step S200 may be applied as they are, and the process proceeds to step S250. On the other hand, if the absolute value | Δθ | of the throttle change is larger than the threshold value θth (YES in step S210), it is better to consider the response delay of the turbocharger in order to improve the accuracy of engine torque estimation. In S220 to S240, the dead time Td and the first-order lag constant Tc are reset.

  First, the air amount measured by the air flow meter before and after the throttle change is estimated on a map (step S220).

FIG. 10 is an example of a map for obtaining a change in the air amount.
In FIG. 10, the horizontal axis represents the engine speed Ne, and the vertical axis represents the engine load factor KL. The engine speed Ne is obtained based on a signal from the crank position sensor 122 of FIG. The engine load factor KL is obtained by dividing the amount of air filled in the cylinder of each cylinder (in-cylinder charged air amount) by the air density in the standard state corresponding to the cylinder volume of each cylinder when the intake stroke is completed. is there. That is,
Load factor KL = (in-cylinder charged air amount) / (standard air density for cylinder volume)
The engine load factor KL is defined by the following equation (4), for example.
KL = (Mc / ((DSP / NCYL) · ρastd)) · 100 (4)
In this equation (1), Mc indicates the cylinder air filling amount (g) which is the amount of air charged in the cylinder of each cylinder when the intake stroke is completed, and the DSP indicates the engine displacement (liter). NCYL represents the number of cylinders, and ρastd represents the air density (about 1.2 g / liter) in the standard state (1 atm, 25 ° C.).

When the flow rate of air sucked into the cylinder from the intake pipe is referred to as in-cylinder intake air flow rate mc (g / sec), the in-cylinder charged air amount Mc is determined using the time tiv (sec) required for one intake stroke. It is expressed as equation (5).
Mc = mc · tiv (5)
Therefore, when each coefficient is collectively expressed by kk, the engine load factor KL is also expressed by the following equation (6).
KL = kk · mc (6)
Here, the cylinder intake air flow rate mc is determined based on the output of the air flow meter 154. The map of FIG. 10 estimates the air amount based on the engine load factor KL and the engine speed Ne. That is, estimating the air amount based on the engine load factor KL also expresses that the air amount is estimated based on the output of the air flow meter 154 from the relationship of the equations (4), (5), and (6). (Step S220).

  In FIG. 10, when the engine speed is Ne1 and the engine load factor determined based on the output of the air flow meter 154 is KL1, the position of the point P is the air amount indicated on the map. At the point P, the air amount ΔQ is displayed as being large. This indicates that a value obtained by further correcting the amount of air detected by the air flow meter 154 by ΔQ is used as the estimated value. The point P belongs to a region where the correction value ΔQ is large.

  Note that a region where the air amount ΔQ is displayed as small means that the correction amount is small, and therefore a value that is almost close to the air amount detected by the air flow meter 154 is estimated to be the air amount.

  Subsequently, an estimated air amount difference Qd before and after the throttle change is calculated (step S230). As the air amount before the throttle change, an actual measurement value obtained from the output of the air flow meter is used. For this reason, the air amount before the throttle change is temporarily held in a memory or the like, and the magnitude of the throttle change in step S230 is determined. If the throttle change amount is larger than the threshold value, the air amount before the change is read from the memory or the like. It is. The air amount after the throttle change is obtained by adding the air amount ΔQ obtained by the map of FIG. 10 to the actual measured value of the air flow meter after the throttle change. The estimated air amount difference Qd before and after the throttle change can be obtained by subtracting the air amount before the throttle change from the air amount after the throttle change.

  Next, the dead time Td and the first-order lag time constant Tc are set based on the estimated air amount difference Qd obtained in step S230 (step S240).

  Td = ftd (Qd) indicates that the dead time Td is determined as a function using the estimated air amount difference Qd as a variable, and can be previously mapped.

  In this case, for the dead time Td, the relationship between the estimated air amount difference Qd and the dead time Td is obtained in advance and stored in the ROM 74 as a map. When the estimated air amount difference Qd is given, the corresponding dead time Td is calculated from the map. Set by deriving.

  FIG. 11 is a diagram showing an example of a map that can be used to determine the dead time Td in step S240.

  In FIG. 11, the vertical axis represents the dead time Td and the estimated air amount difference Qd calculated in step S230. As the estimated air amount difference Qd increases, the dead time Td is set larger.

  Further, the relationship between the estimated air amount difference Qd and the first-order lag time constant Tc is obtained in advance and stored in the ROM 74 as a map. When the estimated air amount difference Qd is given, a corresponding first-order lag time constant Tc is derived from the map and set.

  FIG. 12 is a diagram showing an example of a map that can be used to determine the first-order lag time constant Tc in step S240.

  In FIG. 12, the vertical axis represents the first-order lag time constant Tc, and the horizontal axis represents the estimated air amount difference Qd. As the estimated air amount difference Qd increases, the first-order lag time constant Tc is set larger.

  Then, the estimated engine torque Test is set by applying response delay processing to the target torque using the dead time Td and the first-order lag time constant Tc set in step S200 or set in steps S210 to S240 ( In step S250, the process proceeds to the flowchart of FIG. 3 (step S260).

  FIG. 13 is a diagram showing a transient change in the estimated engine torque when the throttle is suddenly closed.

  As shown in FIG. 13, according to the control of the present embodiment, when the throttle opening greatly decreases at time t1, if the difference in the air amount before and after the change is small, the dead time and the time constant are set small. Then, the engine estimated torque changes as indicated by the solid line Te1. On the other hand, if the air amount difference before and after the change in the throttle opening is small, the dead time and the time constant are set large, and the estimated engine torque changes as indicated by the broken line Te2.

  FIG. 14 is a diagram showing a transient change in the estimated engine torque when the throttle is suddenly opened.

  As shown in FIG. 14, according to the control of the present embodiment, when the throttle opening greatly increases at time t1, if the difference in air amount before and after the change is small, the dead time and the time constant are set small. Then, the engine estimated torque changes as indicated by the solid line Te3. On the other hand, if the air amount difference before and after the change in the throttle opening is small, the dead time and the time constant are set large, and the estimated engine torque changes as indicated by the broken line Te4.

  FIG. 15 is a waveform diagram for explaining the effect when control is performed by the vehicle power output apparatus of the present embodiment.

  Referring to FIG. 15, it is assumed that the accelerator pedal is changed at time t1 from a state in which the driver depresses the accelerator pedal (WOT state) to a state in which the driver relaxes to an intermediate position (partial state). Then, the throttle valve changes in response to the accelerator pedal. However, since the turbine rotation speed of the supercharger is high for a while due to inertia, the supercharging pressure (intake pressure) changes with a delay as shown by a broken line. Similarly, the engine torque Te changes with a delay as indicated by a broken line.

  On the other hand, when the control according to the present embodiment is not performed, if written extremely, the estimated engine torque rapidly decreases at time t1, as shown by the waveform group A, so that it is shown in FIG. The target torque Tm1 * of the motor generator MG1 that is controlled so as to be balanced with the estimated engine torque on the alignment chart also decreases rapidly.

  However, since engine torque Te remains large for a while after time t1 due to a delay in the change in supercharging pressure, the feedback acts so that the required torque of the vehicle is output to the wheels, and the feedback of torque of motor generator MG1. The amount increases.

  At this time, if the deviation is too large, the feedback may fail.For example, as a result of limiting the feedback amount to prevent sudden change, the required torque cannot be output to the wheels, causing the driver to feel uncomfortable, There is a possibility that power is generated by the generator MG1.

  On the other hand, according to waveform group B indicating the case where the control according to the present embodiment is performed, the estimated engine torque changes in the same manner as the change in engine torque Te, so that the torque corresponding to the feedforward of motor generator MG1. Accuracy is improved, the amount of feedback is reduced, and output control of required torque and battery charge control are performed satisfactorily.

  The engine torque estimation process described in the flowchart of FIG. 7 may be performed by the engine electronic control unit or the hybrid electronic control unit.

  FIG. 16 is a diagram for schematically illustrating a case where the engine estimated torque calculation process is performed by the engine electronic control unit.

  In the case illustrated in FIG. 16, in the engine electronic control unit, the air amount is calculated from a four-dimensional map into which the throttle opening, the supercharging pressure, the valve timing, and the engine speed are input, and the air amount and the ignition timing are calculated. And the intake air temperature are processed by the torque calculation unit, and as a result, the estimated engine torque is input to the hybrid electronic control unit 70.

  Hybrid electronic control unit 70 causes motor control ECU to control motor generator MG1 based on the applied engine estimated torque.

  FIG. 17 is a diagram for schematically illustrating a case where the engine estimated torque calculation process is performed by the hybrid electronic control unit.

  In the case illustrated in FIG. 17, the air amount is calculated from a four-dimensional map in which the throttle opening, the supercharging pressure, the valve timing, and the engine speed are input by the engine electronic control unit, and is output to the hybrid electronic control unit. The In the hybrid control ECU, the air amount and the engine speed are processed by a torque calculation unit to obtain an engine estimated torque. Further, the hybrid control ECU controls the motor generator MG1 based on the engine estimated torque. Have the ECU do this.

  The torque estimation process may be performed in the engine electronic control unit as shown in FIG. 16, or may be performed in the hybrid electronic control unit as shown in FIG.

  Finally, the present embodiment will be generally described with reference to FIGS. 1 and 2 again. The power output apparatus for a vehicle according to the present embodiment includes an internal combustion engine (engine 22) including an air flow meter 154, a supercharger 200, and a throttle valve 166 in an intake path, a first rotating electrical machine (motor generator MG1), The internal combustion engine, the first rotating electrical machine, and the power split mechanism 30 in which the drive shaft for driving the wheels is connected to the three input shafts, and the amount of change in the opening of the throttle valve 166 is larger or smaller than the threshold value. The control device (HV-ECU 70, motor ECU 40, engine ECU 24) that controls the first rotating electrical machine to estimate the output torque of the internal combustion engine by different processing and output the required driving force to the drive shaft (ring gear shaft 32a). ). In the embodiment, the control device is realized by the HV-ECU 70, the motor ECU 40, and the engine ECU 24. However, these may be combined into one ECU or divided into a plurality of different ECUs.

  Preferably, the control device sets first and second constants for estimating a delay in change of the output torque Te with respect to the target torque Te * of the internal combustion engine, and sets either of the first and second constants. Based on this, the response delay of the output torque of the internal combustion engine is estimated. As set in step S200 of FIG. 7, the first constant is a constant (dead time Td, time constant Tc) applied when the amount of change in the opening of the throttle valve is smaller than the threshold value. As set in steps S220 to S240 in FIG. 7, the second constant is a constant applied when the amount of change in the opening of the throttle valve 166 is larger than the threshold value.

  More preferably, as shown in FIGS. 10 to 12, the control device sets the second constant according to the load factor KL of the internal combustion engine.

  More preferably, the control device stores the air amount measured by the air flow meter 154. Then, when calculating the second constant, the control device is based on the air amount before the change in the throttle valve opening exceeding the threshold, and the load factor and the rotational speed of the internal combustion engine as shown in FIG. Then, an air amount difference from the air amount after the change in the opening degree is corrected by correcting the delay in the intake air amount change after passing through the supercharger. Then, as shown in FIGS. 11 and 12, the control device sets the second constant based on the air amount difference.

  Preferably, the vehicle power unit further includes a second rotating electrical machine (motor generator MG2) that transmits and receives mechanical power to and from the drive shaft through a transmission path different from power split mechanism 30. The first rotating electrical machine mainly operates as a generator, and the second rotating electrical machine mainly operates as an electric motor.

  According to the present embodiment, it is possible to suppress overcharge and unintended vehicle behavior due to a response delay in the intake pipe pressure. Therefore, it is possible to realize a hybrid vehicle that can be stably controlled with a configuration employing a supercharged engine.

  Further, the present embodiment discloses a control method executed by the control device. This control method can be executed by software using a computer. A program for causing a computer to execute this control method is read from a recording medium (ROM, CD-ROM, memory card, etc.) recorded in a computer-readable manner into a computer in a vehicle control device or provided through a communication line. You may do it.

  In this embodiment, an example is shown in which the present invention is applied to a series / parallel hybrid system in which a motor, a generator, and an engine are used as power sources, and the power of the engine can be divided and transmitted to an axle and a generator by a power split mechanism. It was. However, the present invention is applicable as long as the engine torque is estimated and torque control of the generator or motor is performed, and both the motor and the generator are not necessarily provided.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

It is the schematic of the structure of the hybrid vehicle 20 carrying the internal combustion engine as embodiment of this invention. It is the figure which showed the structure regarding the engine 22 of the hybrid vehicle 20 shown in FIG. 1 in detail. It is a flowchart which shows an example of the drive control routine performed by HV-ECU70 of the hybrid vehicle 20 of an Example. It is a figure which shows an example of the map for request | requirement torque setting. It is a figure showing signs that target speed Ne * and target torque Te * are set up in an example of an operation line of engine 22. FIG. 3 is a collinear diagram showing a dynamic relationship between the rotational speed and torque of each rotary element of the power split mechanism 30. FIG. It is a flowchart which shows the setting process of the engine estimated torque Test of step S140 of FIG. It is the figure which showed an example of the map which can be used in order to define the dead time Td in step S200. It is the figure which showed an example of the map which can be used in order to determine primary delay time constant Tc in step S200. It is an example of the map for calculating | requiring the change of air quantity. It is the figure which showed an example of the map which can be used in order to define the dead time Td in step S240. It is the figure which showed an example of the map which can be used in determining the primary delay time constant Tc in step S240. It is the figure which showed the transitional change of the engine estimated torque when a throttle is closed suddenly. It is the figure which showed the transitional change of the engine estimated torque when a throttle is opened suddenly. It is a wave form diagram for demonstrating the effect at the time of control by the power output device of the vehicle of this Embodiment. It is a figure for demonstrating schematically the case where an engine estimated torque calculation process is performed by the engine electronic control unit. It is a figure for demonstrating roughly the case where an engine estimated torque calculation process is performed by the electronic control unit for hybrids.

Explanation of symbols

  20 hybrid vehicle, 22 engine, 24 electronic control unit for engine, 26 crankshaft, 28 damper, 30 power split mechanism, 31 sun gear, 32 ring gear, 32a ring gear shaft, 33 pinion gear, 34 carrier, 35 reduction gear, 41, 42 inverter , 43, 44 Rotation position detection sensor, 50 battery, 51 Temperature sensor, 52 Battery electronic control unit, 54 Power line, 60 Gear mechanism, 62 Differential gear, 63a, 63b Drive wheel, 70 Hybrid electronic control unit, 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, 102, 156, 160 Intake passage, 104 Intake valve, 106 Fuel injection injector, 108 Combustion chamber, 110 Spark plug, 112 Cylinder block, 114 Piston, 116 Connecting rod, 118 Timing rotor, 122 Crank position sensor, 124 Cylinder head, 128 Exhaust valve, 130 Exhaust passage, 150 Inlet, 152 Air cleaner, 154 Air flow meter, 162 Intercooler, 166 Throttle valve, 168 Throttle motor, 170 Intake pipe pressure sensor, 172 Intake temperature sensor, 180 Exhaust pipe, 182 Catalyst, 200 Turbocharger, 202 Compressor, 204 Turbine, 206 Compressor wheel, 208 Turbine wheel, 210 shaft, 233 A Serupedaru, 304 timing rotor, MG1, MG2 motor-generator.

Claims (10)

An internal combustion engine including an air flow meter, a supercharger, and a throttle valve in the intake path;
A first rotating electrical machine;
A power split mechanism in which the internal combustion engine, the first rotating electrical machine, and a drive shaft for driving wheels are connected to three input shafts;
In order to estimate the output torque of the internal combustion engine by different processing depending on whether the amount of change in the opening of the throttle valve is larger or smaller than the threshold value, and output the required driving force to the drive shaft, the first A power output device for a vehicle, comprising: a control device that controls the rotating electrical machine. The control device sets first and second constants for estimating a delay in change of the output torque with respect to a target torque of the internal combustion engine, and based on one of the first and second constants, Estimate the response delay of the output torque of the internal combustion engine,
The first constant is a constant applied when the amount of change in the opening of the throttle valve is smaller than the threshold value,
2. The vehicle power output apparatus according to claim 1, wherein the second constant is a constant applied when an amount of change in the opening of the throttle valve is larger than the threshold value.   The power output device for a vehicle according to claim 2, wherein the control device sets the second constant according to a load factor of the internal combustion engine.   The control device stores the air amount measured by the air flow meter, and calculates the second constant, the air amount before the throttle valve opening change exceeding the threshold value, and the load An air amount difference between the air amount after the change in the opening degree corrected for a delay in the change in the intake air amount after passing through the supercharger based on the engine speed and the rotational speed of the internal combustion engine, and the air amount difference The power output apparatus for a vehicle according to claim 3, wherein the second constant is set based on A first rotating electrical machine that transmits and receives mechanical power to and from the drive shaft via a transmission path different from the power split mechanism;
The first rotating electrical machine operates mainly as a generator,
The power output apparatus for a vehicle according to claim 1, wherein the second rotating electrical machine operates mainly as an electric motor. An internal combustion engine including an air flow meter, a supercharger, and a throttle valve in the intake path, a first rotating electrical machine, the internal combustion engine, the first rotating electrical machine, and a drive shaft for driving wheels are provided as three input shafts. A control method for a vehicle power output device including a connected power split mechanism,
Estimating the output torque of the internal combustion engine by different processing depending on whether the amount of change in the opening of the throttle valve is larger or smaller than a threshold value;
And a step of controlling the first rotating electric machine in order to output the required driving force to the driving shaft. The step of estimating the output torque includes:
Setting a first constant for estimating a delay in a change in output torque with respect to a target torque of the internal combustion engine;
Setting a second constant for estimating a delay in the change of the output torque with respect to the target torque of the internal combustion engine;
Estimating a response delay of the output torque of the internal combustion engine based on one of the first and second constants,
The first constant is a constant applied when the amount of change in the opening of the throttle valve is smaller than the threshold value,
The method for controlling a power output apparatus for a vehicle according to claim 6, wherein the second constant is a constant applied when an opening change amount of the throttle valve is larger than the threshold value.   The method for controlling a power output apparatus for a vehicle according to claim 7, wherein the step of setting the second constant sets the second constant according to a load factor of the internal combustion engine.   The step of setting the second constant stores the air amount measured by the air flow meter, and calculates the second constant before the throttle valve opening change that exceeds the threshold value. Calculates the air amount difference between the air amount and the air amount after the opening change corrected for the delay of the intake air amount change after passing through the supercharger based on the load factor and the rotational speed of the internal combustion engine The method for controlling the power output apparatus for a vehicle according to claim 8, wherein the second constant is set based on the air amount difference. A first rotating electrical machine that transmits and receives mechanical power to and from the drive shaft via a transmission path different from the power split mechanism;
The first rotating electrical machine operates mainly as a generator,
The method according to claim 6, wherein the second rotating electrical machine operates mainly as an electric motor.

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