JP5206566B2 - Vehicle and control method thereof - Google Patents

Description

  The present invention relates to a vehicle and a control method thereof.

  Conventionally, as a vehicle, an increase coefficient is set so that the increase becomes larger as the fuel cut continues for a long time after returning from the fuel cut, and the delay time that is a waiting time until the air-fuel ratio feedback control is started is set to the fuel cut. Has been proposed (see Patent Document 1, for example). In this vehicle, the fuel increase correction at the time of fuel cut return can be performed more appropriately, and the air-fuel ratio feedback control can be started at a more appropriate timing.

JP 2008-138628 A

  By the way, there is a so-called hybrid vehicle including a battery and a motor in a vehicle including an engine. In such a vehicle, while the battery is charged, the engine may be repeatedly loaded and unloaded as in the vehicle described in Patent Document 1. However, in such a vehicle, when feedback control of the required power of the engine is performed in a low temperature state, the generated power may become excessive, and in a low temperature state, the battery is sufficiently charged in order to further protect the battery. In some cases, the battery is not sufficiently protected when the battery is fully charged in a low temperature state.

  The present invention has been made in view of such problems, and it is a main object of the present invention to provide a vehicle capable of protecting the power storage means in a low temperature state and more appropriately charging the power storage means, and a control method thereof. And

  The present invention adopts the following means in order to achieve the main object described above.

The vehicle of the present invention
An internal combustion engine;
A generator for generating electricity using power from the internal combustion engine;
An electric motor capable of outputting driving power;
Power storage means for exchanging power with the generator and the motor;
When the electric power generated by the generator using the power from the internal combustion engine is stored in the power storage means, the generated power is input to the power storage means when the temperature of the power storage means is equal to or higher than a predetermined temperature. When the limit is exceeded, the internal combustion engine is operated with no load, and when the generated power is within the input limit of the power storage means, feedback control is performed on the required power required for the internal combustion engine to load the internal combustion engine. The internal combustion engine is controlled so that the internal combustion engine shifts to load operation and is stored in the power storage means at a low temperature when the temperature of the power storage means is lower than a predetermined temperature. Control means for controlling the internal combustion engine with limitation over a predetermined time;
Is provided.

  In this vehicle, when the temperature of the power storage means is equal to or higher than a predetermined temperature, when the generated power exceeds the input limit of the power storage means, the internal combustion engine is operated with no load, and when the generated power is within the input limit of the power storage means Feedback control relating to required power required for the internal combustion engine is executed to load-drive the internal combustion engine. On the other hand, when the internal combustion engine is shifted to load operation and stored in the power storage means when the temperature of the power storage means is lower than the predetermined temperature, the internal combustion engine is limited by limiting feedback control related to the required power of the internal combustion engine for a predetermined time. To control. Here, if the feedback control related to the required power of the internal combustion engine is executed as it is when the internal combustion engine is shifted to the load operation at a low temperature, the response delay of the internal combustion engine may be taken in and an output excessive state may occur. Here, since the feedback control related to the required power of the internal combustion engine is limited for a predetermined time, this excessive output state can be suppressed, and the shift to the no-load operation of the internal combustion engine in which the power storage means cannot be charged. It can be suppressed. Thus, since the load operation / no-load operation of the internal combustion engine is switched based on the input restriction of the power storage means, the power storage means can be further protected. Further, since the load operation of the internal combustion engine can be continued further in the low temperature state, the power storage means can be charged more appropriately. Here, “non-load operation of the internal combustion engine” may include a stopped state in addition to the self-sustained operation.

  In the vehicle according to the present invention, when the feedback control of the internal combustion engine is limited, the control means does not perform the feedback control of the internal combustion engine until the predetermined time elapses, and after the predetermined time elapses, the internal combustion engine It may be a means for starting the feedback control. In this way, by not performing feedback control of the internal combustion engine, it is possible to protect the power storage means in a low temperature state and to charge the power storage means more appropriately. Here, the “predetermined time” may be, for example, a constant value determined empirically, or may be a change value empirically determined so as to increase as the required power required for the internal combustion engine increases.

  In the vehicle according to the present invention, the control means limits the feedback control of the internal combustion engine, and considers the expected opening considering the response delay between the required power required for the internal combustion engine and the generated power generated by the generator. It may be a means for controlling the throttle opening of the internal combustion engine every time. By so doing, it is possible to compensate for the reduction in the amount of power generated by limiting the feedback control of the internal combustion engine with the estimated opening degree. Here, the “expected opening” may be, for example, a constant value that is empirically determined, or may be a change value that is empirically determined so as to decrease with time.

  In the vehicle according to the aspect of the invention, when the feedback control of the internal combustion engine is limited, the control means limits the reflected value to the required power given by the feedback control of the internal combustion engine to a smaller value over the predetermined time. It may be a means. In this way, by limiting the reflected value to the required power, the power storage means can be protected relatively easily and the power storage means can be charged more appropriately. At this time, when the control means limits the feedback control of the internal combustion engine, the feedback control of the internal combustion engine tends to increase the reflected value to the required power given by the feedback control of the internal combustion engine with time. It is good also as a means to perform.

  The control means satisfies at least one of when the required driving force for traveling is a low driving force less than a predetermined driving force and when the vehicle is stopped and when the temperature of the power storage means is a low temperature lower than a predetermined temperature. When the internal combustion engine shifts to load operation and is stored in the power storage means, the internal combustion engine may be controlled by limiting feedback control related to the required power of the internal combustion engine over a predetermined time. When the required driving force for traveling is a low driving force less than a predetermined driving force and when the vehicle is stopped, the output from the internal combustion engine is less stable, and therefore, the present invention is highly meaningful.

  In the vehicle of the present invention, the power storage means may be a lithium ion secondary battery. Lithium ion secondary batteries have high significance in applying the present invention because the power that can be input in a low temperature state is relatively small.

  The vehicle of the present invention is connected to three shafts of a drive shaft coupled to an axle, an output shaft of the internal combustion engine, and a rotating shaft of the generator, and power input / output to / from any two of the three shafts. 3 axis type power input / output means for inputting / outputting power to / from the remaining shafts.

The vehicle control method of the present invention includes:
A vehicle comprising: an internal combustion engine; a generator that generates electric power using power from the internal combustion engine; an electric motor capable of outputting driving power; and a power storage unit that exchanges electric power with the generator and the electric motor. A control method,
When the electric power generated by the generator using the power from the internal combustion engine is stored in the power storage means, the generated power is input to the power storage means when the temperature of the power storage means is equal to or higher than a predetermined temperature. When the limit is exceeded, the internal combustion engine is operated with no load, and when the generated power is within the input limit of the power storage means, feedback control is performed on the required power required for the internal combustion engine to load the internal combustion engine. The internal combustion engine is controlled so that the internal combustion engine shifts to a load operation at a low temperature when the temperature of the power storage means is lower than a predetermined temperature, and the power storage means stores power. And limiting the feedback control over a predetermined time to control the internal combustion engine.

  In this vehicle control method, similarly to the above-described vehicle, since the load operation / no-load operation of the internal combustion engine is switched based on the input restriction of the power storage means, the power storage means can be further protected. In addition, in the low temperature state, it is possible to suppress an excessive output state caused by taking in a response delay of the internal combustion engine, and it is possible to continue the load operation of the internal combustion engine, so that the power storage means can be charged more appropriately. In this vehicle control method, various aspects of the vehicle described above may be adopted, and steps for realizing each function of the vehicle described above may be added.

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 a stop-time power storage control routine that is executed by the hybrid electronic control unit 70; It is explanatory drawing which shows an example of the relationship between battery temperature Tb and input-output restrictions Win and Wout. It is explanatory drawing which shows an example of the relationship between the electrical storage amount SOC of the battery 50, and the correction coefficient of input / output restrictions Win and Wout. It is explanatory drawing which shows a mode that an example of the operating line of the engine 22, and target rotational speed Ne * and target torque Te * are set. FIG. 6 is an explanatory diagram showing an example of a collinear diagram showing a dynamic relationship between the rotational speed and torque of each rotary element of the power distribution and integration mechanism 30. 7 is a flowchart illustrating an example of another stop-time power storage control routine executed by the hybrid electronic control unit 70; It is explanatory drawing which shows an example of the reflection rate k for feedback control of request | requirement power Pe *. FIG. 11 is a configuration diagram showing an outline of a configuration of a hybrid vehicle 120 according to a modification. FIG. 11 is a configuration diagram showing an outline of a configuration of a hybrid vehicle 220 of a modified example.

  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 according to an embodiment of the present invention. As shown in the figure, the hybrid vehicle 20 of the embodiment includes an engine 22, a three-shaft power distribution / integration mechanism 30 connected to a crankshaft 26 as an output shaft of the engine 22 via a damper 28, and power distribution / integration. A motor MG1 capable of generating electricity connected to the mechanism 30, a reduction gear 35 attached to a ring gear shaft 32a as a drive shaft connected to the power distribution and integration mechanism 30, a motor MG2 connected to the reduction gear 35, And a hybrid electronic control unit 70 for controlling the entire vehicle.

  The engine 22 is configured as an internal combustion engine capable of outputting power using a hydrocarbon-based fuel such as gasoline or light oil, and the air purified by an air cleaner 122 is passed through a throttle valve 124 as shown in FIG. Inhalation and gasoline are injected from the fuel injection valve 126 to mix the sucked air and gasoline. The mixture is sucked into the fuel chamber through the intake valve 128 and is explosively burned by an electric spark from the spark plug 130. Thus, the reciprocating motion of the piston 132 pushed down by the energy is converted into the rotational motion of the crankshaft 26. Exhaust gas from the engine 22 is discharged to the outside air through a purification device (three-way catalyst) 134 that purifies harmful components such as carbon monoxide (CO), hydrocarbons (HC), and nitrogen oxides (NOx).

  The engine 22 is controlled by an engine electronic control unit (hereinafter referred to as an engine ECU) 24. 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. . The engine ECU 24 includes signals from various sensors that detect the state of the engine 22, a crank position from the crank position sensor 140 that detects the rotational position of the crankshaft 26, and a water temperature sensor 142 that detects the temperature of cooling water in the engine 22. From the cooling water temperature from the combustion chamber, the in-cylinder pressure Pin from the pressure sensor 143 installed in the combustion chamber, the intake valve 128 that performs intake and exhaust to the combustion chamber, and the cam position sensor 144 that detects the rotational position of the camshaft that opens and closes the exhaust valve Cam position, throttle position from throttle valve position sensor 146 for detecting the position of throttle valve 124, air flow meter signal AF from air flow meter 148 attached to the intake pipe, and temperature sensor also attached to the intake pipe Intake air temperature from 49, the air-fuel ratio AF from an air-fuel ratio sensor 135a, such as oxygen signal from an oxygen sensor 135b is input via the input port. The engine ECU 24 also integrates various control signals for driving the engine 22, such as 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, and an igniter. The control signal to the ignition coil 138 and the control signal to the variable valve timing mechanism 150 that can change the opening / closing timing of the intake valve 128 are output via the output port. 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 power distribution and integration 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, A planetary gear mechanism is provided that includes a carrier 34 that holds a plurality of pinion gears 33 so as to rotate and revolve, and that performs differential action using the sun gear 31, the ring gear 32, and the carrier 34 as rotational elements. In the power distribution and integration mechanism 30, the crankshaft 26 of the engine 22 is connected to the carrier 34, the motor MG1 is connected to the sun gear 31, and the reduction gear 35 is connected to the ring gear 32 via the ring gear shaft 32a. When functioning as a generator, power from the engine 22 input from the carrier 34 is distributed according to the gear ratio between the sun gear 31 side and the ring gear 32 side, and when the motor MG1 functions as an electric motor, the engine input from the carrier 34 The power from 22 and the power from the motor MG1 input from the sun gear 31 are integrated and output to the 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.

  The motor MG1 and the motor MG2 are both configured as well-known synchronous generator motors that can be driven as generators and can be driven as motors, and exchange power with the battery 50 via inverters 41 and 42. The power line 54 connecting the inverters 41 and 42 and the battery 50 is configured as a positive electrode bus and a negative electrode bus shared by the inverters 41 and 42, and the electric power generated by one of the motors MG1 and MG2 It can be consumed by a motor. Therefore, battery 50 is charged / discharged by electric power generated from one of motors MG1 and MG2 or insufficient electric power. If the balance of electric power is balanced by the motors MG1 and MG2, the battery 50 is not charged / discharged. The motors MG1 and MG2 are both driven and controlled by a motor electronic control unit (hereinafter referred to as a motor ECU) 40. The motor ECU 40 detects signals necessary for driving and controlling the motors MG1 and MG2, such as signals from rotational position detection sensors 43 and 44 that detect the rotational positions of the rotors of the motors MG1 and MG2, and current sensors (not shown). The phase current applied to the motors MG1 and MG2 to be applied is input, and a switching control signal to the inverters 41 and 42 is output from the motor ECU 40. The motor ECU 40 is in communication with the hybrid electronic control unit 70, controls the driving of the motors MG1 and MG2 by a control signal from the hybrid electronic control unit 70, and, if necessary, data on the operating state of the motors MG1 and MG2. Output to the hybrid electronic control unit 70.

  The battery 50 is configured as a lithium ion secondary battery, and is managed by a battery electronic control unit (hereinafter referred to as a battery ECU) 52. The battery ECU 52 receives signals necessary for managing the battery 50, for example, an inter-terminal voltage Vb from the voltage sensor 51 a installed between the terminals of the battery 50, and a power line 54 connected to the output terminal of the battery 50. The charging / discharging current Ib from the attached current sensor 51b, the battery temperature Tb from the temperature sensor 50c attached to the battery 50, and the like are input. Output to the control unit 70. Further, the battery ECU 52 calculates the storage amount SOC based on the integrated value of the charge / discharge current Ib detected by the current sensor 51b in order to manage the battery 50, or based on the calculated storage amount SOC and the battery temperature Tb. The input / output limits Win and Wout, which are the maximum allowable power that may charge / discharge the battery 50, are calculated.

  The hybrid electronic control unit 70 is configured as a microprocessor centered on the CPU 72, and in addition to the CPU 72, a ROM 74 for storing processing programs, a RAM 76 for temporarily storing data, an input / output port and communication not shown. And a port. The hybrid electronic control unit 70 includes an ignition signal from an ignition switch 80, a shift position SP from a shift position sensor 82 that detects the operation position of the shift lever 81, and an accelerator pedal position sensor 84 that detects the amount of depression of the accelerator pedal 83. The accelerator pedal opening Acc from the vehicle, 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 hybrid electronic control unit 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. ing. The shift position SP includes a parking position for parking (P position), a drive position for forward travel (D position), a neutral position (N position), a reverse position for reverse travel (R position), and traveling. A brake position (B position) for applying a greater braking force than that in the drive position when the accelerator is off is prepared.

  The hybrid vehicle 20 of the embodiment thus configured 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. Then, the operation of the engine 22, the motor MG1, and the motor MG2 is controlled so that the required power corresponding to the required torque is output to the ring gear shaft 32a. As operation control of the engine 22, the motor MG1, and the motor MG2, the operation of the engine 22 is controlled 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 the power distribution and integration mechanism 30. Torque conversion operation mode for driving and controlling the motor MG1 and the motor MG2 so that the torque is converted by the motor MG1 and the motor MG2 and output to the ring gear shaft 32a, and the required power and the power required for charging and discharging the battery 50. The engine 22 is operated and controlled so that suitable power is output from the engine 22, and all or part of the power output from the engine 22 with charging / discharging of the battery 50 is the power distribution and integration mechanism 30, the motor MG1, and the motor. The required power is converted to the ring gear shaft 32 with torque conversion by MG2. Charge / discharge operation mode in which the motor MG1 and the motor MG2 are driven and controlled to be output to each other, and a motor operation mode in which the operation of the engine 22 is stopped and the power corresponding to the required power from the motor MG2 is output to the ring gear shaft 32a. and so on.

  Next, the operation of the hybrid vehicle 20 of the embodiment thus configured, particularly the operation when charging the battery 50 when the vehicle is stopped will be described. FIG. 3 is a flowchart showing an example of a stop-time power storage control routine executed by the hybrid electronic control unit 70. This routine is repeatedly executed every predetermined time (for example, every several msec). When this routine is executed, the CPU 72 of the hybrid electronic control unit 70 first generates the generated power Pg generated by the motor MG1 using the required charging power Pb * for charging the battery 50, the battery temperature Tb, and the power of the engine 22. Then, a process of inputting data necessary for control such as the input limit Win of the battery 50 is executed (step S100). Here, the charge / discharge required power Pb * is set based on the remaining capacity (SOC) of the battery 50 and input from the battery ECU 52 by communication. Further, the battery temperature Tb detected by the temperature sensor 51c is input from the battery ECU 52 by communication. Further, the generated electric power Pg is obtained by inputting the product of the torque command value Tm1 of the motor MG1 and the rotation speed Nm1 from the motor ECU 40 by communication. The input limit Win of the battery 50 is set based on the battery temperature Tb of the battery 50 detected by the temperature sensor 51c and the remaining capacity (SOC) of the battery 50, and is input from the battery ECU 52 by communication. did. The input / output limits Win and Wout of the battery 50 are set to the basic values of the input / output limits Win and Wout based on the battery temperature Tb, and the output limiting correction coefficient and input based on the remaining capacity (SOC) of the battery 50 It can be set by setting a correction coefficient for restriction and multiplying the basic value of the set input / output restrictions Win and Wout by the correction coefficient. FIG. 4 shows an example of the relationship between the battery temperature Tb and the input / output limits Win, Wout, and FIG. 5 shows an example of the relationship between the remaining capacity (SOC) of the battery 50 and the correction coefficients of the input / output limits Win, Wout.

  When the data is thus input, the required power Pe * required for the engine 22 is set as the sum of the input charge / discharge required power Pb * and the loss Loss (step S110). Next, it is determined whether or not the set required power Pe * exceeds a predetermined threshold value Pref (step S120). For example, this threshold value Pref is obtained by empirically obtaining the relationship between the operation of the engine 22 and fuel consumption when charging the battery 50, and is set to a value that allows the battery 50 to be charged by operating the engine 22 relatively efficiently. Can do.

  When the required power Pe * does not exceed the predetermined threshold value Pref, the target engine speed Ne * and the target torque Te * of the engine 22 are stopped so that the engine 22 is stopped because the operating efficiency of the engine 22 is low and the battery 50 cannot be charged. And a value “0” is set to the torque command Tm1 * of the motor MG1 (step S140), and the target rotational speed Ne * and the target torque Te * of the engine 22 are set. Based on this, the throttle opening TH, which is the opening of the throttle valve 124 (see FIG. 2), is set (step S150). In the embodiment, the relationship among the target engine speed Ne *, target torque Te *, and throttle opening TH of the engine 22 is determined in advance and stored in the ROM 74 as a throttle opening setting map, and the target engine speed Ne of the engine 22 is stored. When * and target torque Te * are given, the corresponding throttle opening TH is derived from the stored map and set. Here, since the engine 22 is stopped, for example, a value “0” is set to the throttle opening TH. Subsequently, the set target rotational speed Ne * and target torque Te * and throttle opening TH are transmitted to the engine ECU 24, and the torque command Tm1 * of the motor MG1 is transmitted to the motor ECU 40 (step S160). End the routine. The engine ECU 24, which has received the target rotational speed Ne *, the target torque Te *, and the throttle opening TH, controls the throttle valve 124 (see FIG. 2), fuel injection control, ignition control, etc. in the engine 22 to stop the engine 22. Control. Further, the motor ECU 40 that has received the torque command Tm1 * performs switching control of the switching elements of the inverters 41 and 42 so that the motor MG1 is driven by the torque command Tm1 *. Here, control such as fuel injection control and ignition control in the engine 22 is performed to stop the engine 22, and the motor MG1 is controlled so that no power is output from the motor MG1. As described above, when the required power Pe * does not exceed the predetermined threshold value Pref, the engine 22 is stopped and the battery 50 is not charged to suppress the deterioration of fuel consumption.

  On the other hand, if the required power Pe * exceeds the predetermined threshold value Pref in step S120, it is assumed that the battery 50 can be charged by operating the engine 22, and whether the generated power Pg by the motor MG1 exceeds the input limit Win. It is determined whether or not (step S170). When the generated power Pg does not exceed the input limit Win, it is determined whether or not the input battery temperature Tb is lower than a predetermined temperature Tbref (step S180). The predetermined temperature Tbref is a threshold value for determining whether or not the electric power that can be input and output in the battery 50 is relatively low, such as 5 ° C., 0 ° C., −5 ° C., and the like. This value is determined empirically according to the performance. When the battery temperature Tb is not lower than the predetermined temperature Tbref, that is, when the battery 50 is not in a low temperature state, the required power of the engine 22 is accompanied by feedback control of the required power Pe * of the engine 22 (hereinafter referred to as feedback control of the engine 22). Pe * is set (step S190). The setting of the required power Pe * by feedback control of the engine 22 takes the difference between the previous required power Pe * (command value) of the engine 22 and the actually generated generated power Pg (actual output value). Is multiplied by the reflection factor k to add to the required power Pe * of the engine 22 this time. Here, the reflection rate k uses a fixed value (for example, a value “1” or the like). In this way, since the required power Pe * is reset by feedback control of the engine 22, excess or deficiency in output such as response delay can be compensated. Next, the target rotational speed Ne * and the target torque Te * of the engine 22 are set based on the set required power Pe * (step S200), and the target rotational speed Nm1 * of the motor MG1 and the torque command Tm1 * of the motor MG1. Are set (step S210). In this setting, the target torque Te *, the target rotational speed Ne *, the target rotational speed Nm1 *, and the torque command Tm1 * of the motor MG1 are set so that the battery 50 is charged while efficiently driving the engine 22 and the motor MG1. It was supposed to be set. Here, the target torque Te * and the target rotational speed Ne * of the engine 22 can be set based on the operation line for efficiently operating the engine 22 and the required power Pe *. FIG. 6 shows an example of the operation line of the engine 22 and how the target rotational speed Ne * and the target torque Te * are set. As shown in the figure, the target rotational speed Ne * and the target torque Te * can be obtained from the intersection of the operation line and a curve with a constant required power Pe * (Ne * × Te *). In this setting, for example, depending on the range of the value of the required power Pe * of the engine 22, several values (for example, three points) of the target rotational speed Ne * and the target torque Te * with good operating efficiency of the engine 22 are used. The target rotational speed Ne * and the target torque Te * may be set to these values when the required power Pe * is given. Further, the target rotation speed Nm1 * of the motor MG1 can be obtained from a collinear chart showing the dynamic relationship between the rotation speed and torque in the rotating elements of the power distribution and integration mechanism 30 shown in FIG. In the figure, the left S-axis indicates the rotation speed of the sun gear 31 that is the rotation speed Nm1 of the motor 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 rotation speed of the motor MG2. The rotational speed Nr (here, the value “0”) of the ring gear 32 obtained by dividing the number Nm2 by the gear ratio Gr of the reduction gear 35 is shown. Subsequently, in step S150, the throttle opening TH is set based on the target rotational speed Ne * of the engine 22 and the target torque Te *. In step S160, the target rotational speed Ne * and target torque Te * of the engine 22 and the throttle opening TH are transmitted to the engine ECU 24, and the torque command Tm1 * of the motor MG1 is transmitted to the motor ECU 40, and this routine is terminated. . The engine ECU 24 that has received the target rotational speed Ne *, the target torque Te *, and the throttle opening TH, causes the engine 22 to be operated at an operating point indicated by the target rotational speed Ne * and the target torque Te *. The control of the throttle valve 124, the fuel injection control, the ignition control, and the like are performed. Further, the motor ECU 40 that has received the torque command Tm1 * performs switching control of the switching element of the inverter 41 so that the motor MG1 is driven by the torque command Tm1 *. As described above, when the battery 50 is not in a low temperature state, the feedback control of the engine 22 is performed and the battery 50 is charged.

  On the other hand, when the generated power Pg exceeds the input limit Win in step S170, since the generated power is excessive, the engine 22 is operated without load (independent operation) and the charging of the battery 50 is temporarily interrupted. A predetermined idle speed Neidl is set as the target speed Ne * of the engine 22, and a predetermined idle torque Teidl is set as the target torque Te * (step S220). This idle speed Neidl can be set to a speed at which load operation of the engine 22 is performed and power generation is easily started. Subsequently, in step S140, a value “0” is set in the torque command Tm1 * of the motor MG1, and in step S150, the throttle opening TH is set based on the target rotational speed Ne * and the target torque Te * of the engine 22. In step S160, the target rotational speed Ne * and target torque Te * of the engine 22 and the throttle opening TH are transmitted to the engine ECU 24, and the torque command Tm1 * of the motor MG1 is transmitted to the motor ECU 40, and this routine is terminated. The engine ECU 24 that has received the target rotational speed Ne *, the target torque Te *, and the throttle opening TH controls the throttle valve 124 in the engine 22 so that the engine 22 is operated at no load (self-sustaining operation) at the idle rotational speed Neidl. Controls such as fuel injection control and ignition control. The motor ECU 40 that has received the torque command Tm1 * does not generate power in the motor MG1. As described above, when the generated power in the motor MG1 is excessive, the engine 22 is operated independently and stands by until the excessive state of the generated power is settled. Thereby, protection of the battery 50 can be aimed at.

On the other hand, when the battery temperature Tb is lower than the predetermined temperature Tbref in step S180, that is, when the battery 50 is in a low temperature state with a small allowable charge amount, it is determined whether or not the operating state of the engine 22 has been switched to the load operation (step). S230). Here, an affirmative determination is made when and after the engine 22 is switched from the stopped state to the load operation state , or after the engine 22 is switched from the independent operation to the load operation. When the operation state of the engine 22 is not switched to the load operation, it is assumed that the feedback control of the engine 22 can be performed as it is, and the processes after step S190 described above are executed. That is, in step S190, the required power Pe * of the engine 22 is reset by feedback control of the engine 22, and the battery 50 is charged by the set required power Pe *. Thus, even when the battery 50 is in a low temperature state, when it is not shifted to the load operation, the feedback control of the engine 22 is performed as much as possible. 50 can be charged sufficiently.

On the other hand, when the operation state of the engine 22 is switched to the load operation in step S230 and thereafter , it is determined whether or not a predetermined time tref has elapsed since the operation state was switched to the load operation (step S240). The predetermined time tref may be determined empirically at a time when the feedback control of the engine 22 can be resumed. Here, the predetermined time tref is determined empirically so that the longer the required power Pe * of the engine 22 is, the longer the time is, and it is set according to the required power Pe * of the engine 22. When the predetermined time period tref has not elapsed since the operation state of the engine 22 is switched to the load operation, the target rotation speed of the engine 22 is not performed based on the required power Pe * set in step S110 without performing feedback control of the engine 22. Ne * and target torque Te * are set (step S250), and target rotational speed Nm1 * of motor MG1 and torque command Tm1 * of motor MG1 are set (step S260). In this setting, the target torque Te *, the target rotational speed Ne *, the target rotational speed Nm1 *, and the torque command Tm1 * of the motor MG1 are set so that the battery 50 is charged while efficiently driving the engine 22 and the motor MG1. It was supposed to be set. Subsequently, the expected opening TH1 taking into account the response delay between the required power Pe * required for the engine 22 and the generated power Pd generated by the motor MG1 is set as the throttle opening TH of the engine 22 (step S270). This estimated opening degree TH1 is a value such that, for example, the relationship between the input limit Win in the low temperature state of the battery 50 and the output state in the low temperature state of the engine 22 is obtained empirically, and the generated power falls within the input limit Win. It was assumed that The estimated opening TH1 is set to a constant value larger than the required opening required for the engine 22. In step S160, the target rotational speed Ne * and target torque Te * of the engine 22 and the throttle opening TH are transmitted to the engine ECU 24, and the torque command Tm1 * of the motor MG1 is transmitted to the motor ECU 40, and this routine is terminated. . The engine ECU 24 that has received the target rotational speed Ne *, the target torque Te *, and the throttle opening TH has the throttle valve 124 of the engine 22 so that the engine 22 is loaded at the target rotational speed Ne * and the target torque Te *. Controls such as control, fuel injection control, and ignition control are performed. Further, the motor ECU 40 that has received the torque command Tm1 * performs power generation in the motor MG1 in accordance with the torque command Tm1 *. As described above, when the battery 50 is in a low temperature state and the predetermined time tref has not elapsed since the engine 22 shifted to the load operation, the motor MG1 generates electric power with the power of the engine 22 without performing feedback control of the engine 22. Thus, the battery 50 is charged.

  Here, in the lithium ion secondary battery of the battery 50, in a low temperature state, there are restrictions such as high viscosity of the electrolytic solution and high internal resistance, and low allowable upper limit voltage for preventing lithium deposition. Charge capacity may be low. Further, the engine 22 has a large amount of friction in a low temperature state, and it is difficult to accurately control its output, and a difference is likely to occur between the command value and the actual output value. When the feedback control of the required power Pe * is executed with the engine 22 as a load operation in a low temperature state in which the amount of charge to the battery 50 is greatly limited, this difference may be taken in and an excessive output state may easily occur. For this reason, so-called hunting may occur in which the engine 22 alternately repeats the load operation and the independent operation, and it may be difficult to sufficiently charge the battery 50 while protecting the battery 50. Here, when the engine 22 is shifted to a load operation in a low temperature state, the feedback control of the required power Pe * of the engine 22 is not performed (restricted), thereby suppressing this hunting or the like, that is, the load of the engine 22 The interruption of the charging process that occurs when the operation and the independent operation are repeated is suppressed. Further, by setting the estimated opening degree TH1 to be larger in a feedforward manner, an output shortage caused by not performing feedback control of the required power Pe * is compensated.

On the other hand, when the predetermined time tref has elapsed in step S240, the processing after step S190 is executed, and this routine is terminated. That is, in step S190, the required power Pe * of the engine 22 is reset by feedback control of the engine 22, and the battery 50 is charged by the set required power Pe *. Note that after the predetermined time tref has elapsed in step S240, a negative determination is made in step S230. As described above, after the predetermined time tref has elapsed after the battery 50 is in a low temperature state and shifted to the load operation, the feedback control of the engine 22 is resumed, so that the output decrease caused by the response delay of the engine 22 is compensated. The battery 50 can be sufficiently charged.

  According to the hybrid vehicle 20 of the embodiment described above, when the temperature of the battery 50 is equal to or higher than the predetermined temperature Tbref, when the generated power Pg exceeds the input limit Win of the battery 50, the engine 22 is operated without load, When Pg is within the input limit Win of the battery 50, feedback control of the required power Pe * of the engine 22 is executed to drive the engine 22 under load. On the other hand, when the temperature of the battery 50 is low, which is lower than the predetermined temperature Tbref, when the engine 22 shifts to load operation and is stored in the battery 50, the feedback control of the required power Pe * of the engine 22 is limited for a predetermined time tref. Then, the engine 22 is controlled. Here, if the feedback control of the engine 22 is executed as it is when the engine 22 is shifted to the load operation at a low temperature, a response delay of the engine 22 may be taken in and an output excessive state may occur. Here, since the feedback control of the engine 22 is limited for a predetermined time, the excessive output state can be suppressed, and the shift to the no-load operation of the engine 22 that cannot charge the battery 50 can be suppressed. is there. Thus, since the load operation / no-load operation of the engine 22 is switched based on the input limit Win of the battery 50, the battery 50 can be further protected. Moreover, since the load operation of the engine 22 can be continued further in the low temperature state, the battery 50 can be charged more appropriately. Further, when the feedback control of the engine 22 is restricted, the feedback control of the engine 22 is not performed, so that the battery 50 can be protected in a low temperature state and the battery 50 can be charged more appropriately. Furthermore, it is possible to compensate for a decrease in the amount of power generated by limiting the feedback control of the engine 22 by the estimated opening TH1. Furthermore, by switching between the load operation and the self-sustained operation of the engine 22, the battery 50 can be charged and protected relatively easily. Since the battery 50 is in a low temperature state and the output required for the engine 22 is small and hunting is likely to occur, the feedback control of the engine 22 is limited, so that the battery 50 can be further protected and fully charged. . Moreover, since the battery 50 is a lithium ion secondary battery that has a relatively small input power at a low temperature, it is highly significant to apply the present invention. Furthermore, since the feedback control of the engine 22 is executed as much as possible, the decrease in output caused by the response delay of the engine 22 and the like can be compensated, and the battery 50 can be sufficiently charged.

  In the hybrid vehicle 20 of the embodiment, the battery 50 is a lithium ion secondary battery, but is not particularly limited thereto. In addition, if it is a power storage means with a low allowable charge capacity in a low temperature state, the significance of applying the present invention is high.

  In the hybrid vehicle 20 of the embodiment, the feedback control of the engine 22 is limited when the battery temperature Tb of the battery 50 is lower than the predetermined temperature Tbref. However, the temperature at which the battery 50 can be grasped to be in a low temperature state is set. For example, when the intake air temperature from the temperature sensor 149 attached to the intake pipe or the outside air temperature by an outside air temperature sensor (not shown) that can detect the outside air temperature is less than the predetermined temperature Tbref. The feedback control of the engine 22 may be limited assuming that the battery 50 is in a low temperature state.

  In the hybrid vehicle 20 of the embodiment, the predetermined time tref is empirically determined so as to become longer as the required power Pe * of the engine 22 is larger, and is set according to the required power Pe * of the engine 22. However, it is not particularly limited as long as the feedback control of the engine 22 can be resumed. For example, it may be a constant value determined empirically.

  In the hybrid vehicle 20 of the embodiment, the estimated opening TH1 of the throttle opening TH is assumed to be a constant value determined empirically, but is not limited thereto, and is empirically determined to tend to decrease with time. It may be a variable value. By so doing, excessive output from the engine 22 can be further suppressed, and the battery 50 can be further protected and received more appropriately in a low temperature state. Further, the estimated opening TH1 of the throttle opening TH may be a constant value, for example, or a plurality of values may be used according to the battery temperature Tb.

  In the hybrid vehicle 20 according to the embodiment, it has been described that the autonomous operation / load operation of the engine 22 is switched when the battery 50 is charged while the vehicle is stopped. It is good also as what switches the independent operation and load operation of the engine 22 in FIG. For example, the self-sustained operation / load operation of the engine 22 may be switched when the required driving force for traveling is a low driving force less than a predetermined driving force. This “predetermined driving force” may be determined empirically, for example, as a driving force that can be output from the motor MG2 and that allows the engine 22 to operate independently. In the above-described embodiment, the autonomous operation / load operation of the engine 22 is switched. However, this process may be omitted, and the load operation / stop of the engine 22 may be switched.

  In the hybrid vehicle 20 of the embodiment, the hybrid electronic control unit 70 sets the throttle opening TH and transmits it to the engine ECU 24. However, the throttle opening TH may be set on the engine ECU 24 side.

  In the hybrid vehicle 20 of the embodiment, when the battery 50 is in a low temperature state and the engine 22 is shifted to the load operation and the battery 50 is charged, the feedback control of the engine 22 is not performed for a predetermined time tref. However, for example, as shown in FIG. 8, when limiting the feedback control of the engine 22, the reflected value to the required power Pe * given by the feedback control of the engine 22 is reduced to a smaller value over a predetermined time. May be limited. FIG. 8 is a flowchart showing an example of another stop-time power storage control routine. In addition, the same step number is attached | subjected to the process similar to the electrical storage control routine at the time of a stop mentioned above, and the description is abbreviate | omitted. Similar to the stop-time power storage control routine described above, the processing from step S100 to S220 is executed, and when the battery temperature Tb is lower than the predetermined temperature Tbref and the operation state of the engine 22 is not switched to the load operation in step S230, A reflection rate k used for feedback control of the required power Pe * of the engine 22 is set to a predetermined value (step S300). Here, the reflection rate k uses a fixed value (for example, a value “1” or the like). And the process after step S190 is performed similarly to the above-mentioned. On the other hand, when the operation state of the engine 22 is switched to the load operation in step S230, it is determined whether or not the predetermined time tref has elapsed in step S240, and when the predetermined time tref has not elapsed, the reflection rate k is set to the elapsed time. Is set as a change value in accordance with (step S310). As shown in FIG. 9, the reflection rate k has a difference between the command value of the required power Pe * and the actual output value of the generated power Pg as time elapses after the operation state of the engine 22 is switched to load operation. It is set to tend to become larger as time passes so as to be reflected. Here, the reflection rate k according to the elapsed time is set. Next, the required power Pe * by feedback control of the engine 22 is set using the set reflection rate k (step S190), and the processing after step S200 is executed. By so doing, by limiting the reflected value to the required power Pe *, it is possible to protect the battery 50 in a low temperature state relatively easily and to charge the battery 50 more appropriately. The reflection rate k may be determined so as to increase stepwise.

  In the hybrid vehicle 20 of the embodiment, the motor MG2 is attached to the ring gear shaft 32a as the drive shaft via the reduction gear 35. However, the motor MG2 may be directly attached to the ring gear shaft 32a, or instead of the reduction gear 35. Alternatively, the motor MG2 may be attached to the ring gear shaft 32a via a transmission such as a two-speed shift, a three-speed shift, or a four-speed shift.

  In the hybrid vehicle 20 of the embodiment, the power of the motor MG2 is changed by the reduction gear 35 and output to the ring gear shaft 32a. However, as illustrated in the hybrid vehicle 120 of the modification of FIG. May be output to an axle (an axle connected to the wheels 64a and 64b in FIG. 10) different from an axle to which the ring gear shaft 32a is connected (an axle to which the drive wheels 63a and 63b are connected).

  In the hybrid vehicle 20 according to the embodiment, the content of the present invention is applied to the configuration of the hybrid vehicle 20 including the engine 22 and the two motors. However, the content of the present invention is an engine capable of outputting driving power. And a motor capable of generating electric power using the power of the engine and a battery capable of exchanging electric power with the motor, and may be applied to a configuration of a hybrid vehicle. For example, as illustrated in FIG. 22, a motor MG connected to the output shaft of the engine 22, and a transmission 230 connected to the output shaft of the engine 22 and a drive shaft connected to the axle. It does not matter. In this hybrid vehicle 220, the motor MG has functions of a generator and an electric motor. Further, although the hybrid vehicle 20 of the embodiment has been described as a series-parallel type vehicle, it may be a series type hybrid vehicle or a parallel type hybrid vehicle.

  Moreover, it is not limited to what is applied to such a hybrid vehicle, It is good also as forms of hybrid vehicles other than motor vehicles, such as a train. Furthermore, it is good also as a form of the control method of such a hybrid vehicle.

  Here, the correspondence between the main elements of the embodiments and the modified examples and the main elements of the invention described in the column of means for solving the problems will be described. In the embodiment, the engine 22 corresponds to an “internal combustion engine”, the motors MG and MG1 that generate power using the power from the engine 22 correspond to “generators”, and the motors MG and MG2 that output driving power include The battery 50 that corresponds to the “electric motor” and exchanges electric power with the motors MG1 and MG2 corresponds to the “power storage means”, and the electric power generated by the motors MG and MG1 using the power from the engine 22 is stored in the battery 50. When the generated power exceeds the input limit Win of the battery 50, the engine 22 is operated without a load, and when the generated power is within the input limit Win of the battery 50, feedback control regarding the required power Pe * is performed. While controlling the engine 22 to perform a load operation, the engine 50 is at a low temperature when the temperature of the battery 50 is lower than a predetermined temperature. When the battery 22 is shifted to load operation and stored in the battery 50, the hybrid electronic control unit 70 and the engine ECU 24 that control the engine 22 by limiting feedback control related to the required power Pe * of the engine 22 over a predetermined time. The motor ECU 40 corresponds to “control means”. The power distribution and integration mechanism 30 corresponds to “three-axis power input / output means”.

  Here, the “internal combustion engine” is not limited to an internal combustion engine that outputs power using a hydrocarbon fuel such as gasoline or light oil. Any type of internal combustion engine such as an engine may be used. The “generator” is not limited to the motors MG and MG1 configured as the synchronous generator motor, and any type of generator can be used as long as it can generate power using the power of the internal combustion engine, such as an induction motor. It does not matter. The “motor” is not limited to the motors MG and MG2 configured as the synchronous generator motor, and may be any type of electric motor such as an induction motor that can output power for traveling. Absent. The “power storage means” is not limited to the battery 50 as a secondary battery, and may be anything as long as it can exchange electric power with a generator, such as a capacitor. The “control means” is not limited to the combination of the hybrid electronic control unit 70, the engine ECU 24, and the motor ECU 40, and may be configured by more electronic control units or a single electronic unit. It may be configured by a control unit. Further, as the “control means”, when the power generated by the motors MG and MG1 is stored in the battery 50 using the power from the engine 22 when the temperature of the battery 50 is equal to or higher than a predetermined temperature, When the input limit Win of the battery 50 is exceeded, the engine 22 is operated with no load, and when the generated power is within the input limit Win of the battery 50, feedback control is performed on the required power Pe * of the engine 22 so that the engine 22 is loaded. While the engine 22 is controlled, when the temperature of the battery 50 is a low temperature lower than a predetermined temperature, when the engine 22 shifts to a load operation and is stored in the battery 50, feedback control regarding the required power Pe * of the engine 22 is performed at a predetermined time. As long as the engine 22 is controlled over a limited range, any It may be used as the.

  Note that the correspondence between the main elements of the embodiment and the modified example and the main elements of the invention described in the column of means for solving the problem is described in the column of means for the embodiment to solve the problem. Since this is an example for specifically describing the best mode for carrying out the invention, the elements of the invention described in the column of means for solving the problems are not limited. That is, the interpretation of the invention described in the column of means for solving the problems should be made based on the description of the column, and the examples are those of the invention described in the column of means for solving the problems. It is only a specific example.

  The best mode for carrying out the present invention has been described with reference to the embodiments. However, the present invention is not limited to these embodiments, and various modifications can be made without departing from the gist of the present invention. Of course, it can be implemented in the form.

  The present invention is applicable to the hybrid vehicle manufacturing industry and the like.

  20, 120, 220 Hybrid vehicle, 22 engine, 24 engine electronic control unit (engine ECU), 24a CPU, 24b ROM, 24c RAM, 26 crankshaft, 28 damper, 30 power distribution integration mechanism, 31 sun gear, 32 ring gear, 32a ring gear shaft, 33 pinion gear, 34 carrier, 35 reduction gear, 40 motor electronic control unit (motor ECU), 41, 42 inverter, 43, 44 rotational position detection sensor, 50 battery, 51a voltage sensor, 51b current sensor, 51c Temperature sensor, 52 Battery electronic control unit (battery ECU), 54 Power line, 60 Gear mechanism, 62 Differential gear, 63a, 63b Drive wheel, 64a, 64b Wheel, 70 Hybrid Electronic control unit, 72 CPU, 74 ROM, 76 RAM, 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, 135a Air-fuel ratio sensor, 135b Oxygen sensor, 136, Throttle motor, 138 Ignition coil, 140 Crank position sensor 142 Water temperature sensor, 143 Pressure sensor, 144 Cam position sensor, 146 Throttle valve position sensor, 148 Air Rometa, 149 temperature sensor, 150 a variable valve timing mechanism, 230 transmission, MG, MG1, MG2 motor.

Claims (8)

A vehicle,
An internal combustion engine;
A generator for generating electricity using power from the internal combustion engine;
An electric motor capable of outputting driving power;
Power storage means for exchanging power with the generator and the motor;
The electric power generated by using the power from the internal combustion engine said generator when to power storage to the energy storage means, and no-load operation of the internal combustion engine when the front SL generated power exceeds the input limits of the accumulator unit, When the temperature of the power storage means is equal to or higher than a predetermined temperature, when the generated power is within the input limit of the power storage means, feedback control relating to the required power required for the internal combustion engine is executed to load the internal combustion engine. The internal combustion engine is controlled so that the internal combustion engine shifts to load operation and is stored in the power storage means at a low temperature when the temperature of the power storage means is lower than a predetermined temperature. Control means for controlling the internal combustion engine with limitation over a predetermined time;
A vehicle comprising:   When limiting the feedback control of the internal combustion engine, the control means does not perform the feedback control of the internal combustion engine until the predetermined time elapses, and starts the feedback control of the internal combustion engine after the predetermined time elapses. The vehicle according to claim 1, which is a means.   The control means limits the feedback control of the internal combustion engine and sets the expected opening degree of the internal combustion engine to take into account the response delay between the required power required for the internal combustion engine and the generated power generated by the generator. The vehicle according to claim 1, which is means for controlling a throttle opening.   The control means is means for limiting a reflected value to a required power given by feedback control of the internal combustion engine to a smaller value over the predetermined time when limiting the feedback control of the internal combustion engine. The vehicle according to 1.   The control means, when limiting the feedback control of the internal combustion engine, executes the feedback control of the internal combustion engine with a tendency to increase the reflected value to the required power given by the feedback control of the internal combustion engine over time. The vehicle according to claim 4, which is a means.   The vehicle according to any one of claims 1 to 5, wherein the power storage means is a lithium ion secondary battery. The vehicle according to any one of claims 1 to 6,
The remaining shaft is connected to the three shafts of the drive shaft connected to the axle, the output shaft of the internal combustion engine, and the rotating shaft of the generator, based on the power input / output to / from any two of the three shafts. A three-axis power input / output means for inputting / outputting power to the vehicle. A vehicle comprising: an internal combustion engine; a generator that generates electric power using power from the internal combustion engine; an electric motor capable of outputting driving power; and a power storage unit that exchanges electric power with the generator and the electric motor. A control method,
The electric power generated by using the power from the internal combustion engine said generator when to power storage to the energy storage means, and no-load operation of the internal combustion engine when the front SL generated power exceeds the input limits of the accumulator unit, When the temperature of the power storage means is equal to or higher than a predetermined temperature, when the generated power is within the input limit of the power storage means, feedback control relating to the required power required for the internal combustion engine is executed to load the internal combustion engine. The internal combustion engine is controlled so that the internal combustion engine shifts to a load operation at a low temperature when the temperature of the power storage means is lower than a predetermined temperature, and the power storage means stores power. Limiting the feedback control over a predetermined time to control the internal combustion engine;
Vehicle control method.

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