JP4876054B2 - POWER OUTPUT DEVICE, VEHICLE HAVING THE SAME, AND METHOD FOR CONTROLLING POWER OUTPUT DEVICE - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To suppress deterioration in an electricity-storing means while appropriately utilizing the power from the storing means. <P>SOLUTION: In a hybrid vehicle 20, under the condition that a deterioration factor D is not less than a threshold Dref based on a restriction start threshold Dtag, when a value "1" is set to an excess output request flag Fout1 or Fout2, in the case where only the flag Fout2 is set to the value "1", namely, only in the case where the engine 22 is started, output restriction Wout restricted on the basis of the deterioration factor D and the threshold Dtag is temporarily increased (Step S410), thus a hybrid ECU 70, an engine ECU 24, and a motor ECU 40 control the engine 22, and motors MG1, MG2 while keeping the power discharged from a battery 50 within a range of the output restriction Wout. <P>COPYRIGHT: (C)2009,JPO&amp;INPIT

Description

  The present invention relates to a power output device that outputs power to a drive shaft, a vehicle including the same, and a control method for the power output device.

Conventionally, as a power output device for a hybrid vehicle including an internal combustion engine and a traveling motor that output driving power and a motor that can perform cranking for starting the internal combustion engine, a demand for a drive shaft is required. The battery output request is calculated based on the operating point of the internal combustion engine set for the output and the torque command value to the traveling motor, and when the output request is larger than the rated output of the battery, the output request is There is known one that corrects a torque command value of a motor for traveling so as to be equal to or less than an instantaneous output set based on a remaining capacity and a battery temperature (see, for example, Patent Document 1). In this power output apparatus, the internal combustion engine is controlled to operate at an operating point set only during the output possible time, and the driving motor is driven based on the set or corrected torque command value. As a result, the battery performance can be fully exerted and the battery and thus the apparatus can be downsized as compared with the case where the output limit of the battery is limited to the rated output. In addition, this type of power output device starts the internal combustion engine when the accelerator opening is equal to or greater than a threshold value and a predetermined time has elapsed since the previous excess output processing, or during travel using power from the travel motor. It is also known that when a predetermined time has elapsed since the previous excess output processing, a value obtained by adding a predetermined excess output to the rated output of the battery is set as the battery output limit. (For example, refer to Patent Document 2). In this power output device, the battery performance can be sufficiently exhibited, and the battery can be protected more appropriately by setting the excess output at intervals according to the cause of the request for excess output.
JP 2002-058113 A JP 2006-296183 A

  By the way, a battery as a power storage means provided in the power output device as described above generally has a lower limit voltage that is a lower limit of a voltage range that can sufficiently exhibit its performance without deterioration. In some cases, when the discharge at a high current is continued, the output voltage starts to deteriorate even if the output voltage does not reach the lower limit voltage. For this reason, in order to suppress the deterioration of the battery, it is necessary to observe the lower limit voltage and limit the discharge from the battery as necessary to reduce the current. If the excessive output from the temporary battery as described above is allowed more than necessary when it is restricted, there is a risk that deterioration of the power storage means may be promoted.

  Therefore, the main object of the present invention is to suppress deterioration of the power storage means while more appropriately using the power from the power storage means.

  The power output apparatus according to the present invention, the vehicle including the power output apparatus, and the control method of the power output apparatus employ the following means in order to achieve the main object.

The power output device according to the present invention is:
A power output device that outputs power to a drive shaft,
An internal combustion engine capable of outputting power to the drive shaft;
An electric motor capable of outputting power to the drive shaft;
Electric cranking means capable of executing cranking for starting the internal combustion engine;
Power storage means capable of exchanging power with the electric motor and the electric cranking means;
A deterioration factor calculating means for calculating a deterioration factor indicating that the deterioration of the power storage means is started when a predetermined reference value is exceeded based on the value of the current flowing through the power storage means;
Discharge allowable power setting means for setting discharge allowable power which is power allowed for discharging of the power storage means based on the state of the power storage means;
When the calculated deterioration factor is equal to or greater than a predetermined limit start threshold smaller than the reference value, the discharge allowable power set by the discharge allowable power setting means so that the deterioration factor is equal to or less than the reference value. Discharge limiting means for limiting;
When the calculated deterioration factor is less than the limit start threshold, and at least when a predetermined excess output request is made when starting the internal combustion engine, the discharge allowable power set by the discharge allowable power setting means When the excess output request is made when the calculated deterioration factor is equal to or greater than the restriction start threshold, the discharge restriction means restricts only when the internal combustion engine is started. Discharge allowable power increasing means for temporarily increasing discharge allowable power;
Control means for controlling the internal combustion engine, the electric motor, and the electric cranking means so that the electric power discharged from the power storage means is within the range of the discharge allowable power;
Is provided.

  In this power output apparatus, the deterioration factor calculation means calculates a deterioration factor indicating that the deterioration of the power storage means is started when a predetermined reference value is exceeded based on the value of the current flowing through the power storage means. Further, the discharge allowable power setting means sets discharge allowable power that is power allowed for discharge of the power storage means based on the state of the power storage means, and the discharge restriction means has a deterioration factor calculated by the deterioration factor calculation means. The discharge allowable power set by the discharge allowable power setting means is limited so that the deterioration factor is equal to or less than the reference value. When the deterioration factor calculated by the deterioration factor calculation means is less than the limit start threshold value, at least when a predetermined excess output request made at the start of the internal combustion engine is made, the discharge allowable power setting means sets The internal combustion engine, the electric motor, and the electric cranking means are controlled while the discharge allowable power is temporarily increased and the electric power discharged from the power storage means is within the range of the discharge allowable power. In addition, when an excess output request is made when the deterioration factor calculated by the deterioration factor calculation means is equal to or greater than the restriction start threshold, the discharge allowable power limited by the discharge restriction means is only temporarily generated when the internal combustion engine is started. And the internal combustion engine, the electric motor, and the electric cranking means are controlled so that the electric power discharged from the power storage means falls within the range of allowable discharge power. In this way, when the deterioration factor is less than the limit start threshold and the discharge allowable power is not limited by the discharge limiting means, the power storage means is deteriorated by temporarily increasing the discharge allowable power in response to the excess output request. Accordingly, it is possible to obtain power from the power output device with high responsiveness by effectively using the power from the power storage means. In addition, when the deterioration factor is equal to or greater than the limit start threshold and the discharge allowable power is limited by the discharge limiting means, the discharge allowable power is temporarily increased only when an excess output request is made in response to the start request of the internal combustion engine. By making it possible, it is possible to suppress the deterioration of the power storage means due to the continuation of the discharge at a high current by setting the excess output from the power storage means exceeding the original (before temporary increase) discharge allowable power as a necessary minimum. Become. Further, when the discharge allowable power is limited by the discharge limiting means, the discharge allowable power is temporarily increased only when a request for starting the internal combustion engine is made, so that the internal combustion engine is improved in response to the start request. After starting the internal combustion engine, it is possible to start, and while suppressing the discharge from the power storage means while ensuring the required power, the current is reduced, thereby suppressing the deterioration of the power storage means due to the continuation of the discharge It becomes possible to do. Therefore, in this power output device, it is possible to suppress deterioration of the power storage means while appropriately using the power from the power storage means.

  Further, the discharge allowable power increasing means may increase the discharge allowable power by a predetermined amount for a predetermined time when temporarily increasing the discharge allowable power. As a result, it is possible to make the excess output from the power storage means exceeding the original (before temporary increase) discharge power more appropriate while suppressing the deterioration of the power storage means.

  Furthermore, the excess output request may be made when the required degree of driving force for the drive shaft is equal to or greater than a predetermined degree. As a result, when the deterioration factor is less than the limit start threshold and the discharge allowable power is not limited by the discharge limiting means, when the internal combustion engine is started or when the degree of request for the driving force for the drive shaft is high (temporary (temporary) It is possible to obtain power from the power output device with high responsiveness by allowing excess output from the power storage means exceeding the discharge allowable power before increase).

  The discharge limiting unit may reduce the discharge allowable power as the deviation between the calculated deterioration factor and the limit start threshold increases. Thereby, it becomes possible to restrict | limit the discharge from an electrical storage means more appropriately.

  Further, the deterioration factor may be a value based on an integrated value of a current flowing through the power storage means. As a result, the deterioration factor can be calculated as more appropriately indicating the degree of deterioration of the power storage means.

  The electric cranking means is connected to the drive shaft and the engine shaft of the internal combustion engine, and outputs at least part of the power of the internal combustion engine to the drive shaft side with input and output of electric power and power. In addition, power power input / output means capable of exchanging power with the power storage means may be used. Further, the power drive input / output means is connected to three shafts of a generator motor capable of inputting / outputting power, the drive shaft, the engine shaft of the internal combustion engine, and a rotation shaft of the generator motor, Three-axis power input / output means for inputting / outputting power based on power input / output to / from any two of the shafts to / from the remaining shafts may be included.

  The power storage means may be a lithium ion secondary battery. That is, the lithium ion secondary battery has a characteristic that when the discharge at a high current is continued, the output voltage starts to deteriorate even if the output voltage does not reach the lower limit voltage. Therefore, the present invention is extremely suitable for a power output device including a lithium ion secondary battery as a power storage means. However, since the deterioration factor can be calculated for other types of power storage means such as nickel hydride secondary batteries other than lithium ion secondary batteries, the power output device according to the present invention is not limited to lithium ion secondary batteries. Needless to say, the power storage means may be provided.

  A vehicle according to the present invention includes any one of the above-described power output devices and drive wheels connected to the drive shaft. In this vehicle, it is possible to more appropriately use the electric power from the power storage means while suppressing deterioration of the power storage means.

The method for controlling the power output apparatus according to the present invention includes:
An internal combustion engine capable of outputting power to the drive shaft; an electric motor capable of outputting power to the drive shaft; an electric cranking means capable of executing cranking for starting the internal combustion engine; the electric motor and the electric crank; A power output device comprising power storage means capable of exchanging power with ranking means, and discharge allowable power setting means for setting discharge allowable power which is power allowed for discharging of the power storage means based on a state of the power storage means Control method,
(A) calculating a deterioration factor indicating that deterioration of the power storage means is started when a predetermined reference value is exceeded based on a value of a current flowing through the power storage means;
(B) When the deterioration factor calculated in step (a) is equal to or greater than a predetermined limit start threshold value smaller than the reference value, the discharge allowable power setting means so that the deterioration factor is equal to or less than the reference value. Limiting the discharge allowable power set by
(C) When a predetermined excess output request made at the start of the internal combustion engine is made when the deterioration factor calculated in step (a) is less than the limit start threshold, the discharge allowable power setting is performed. The discharge allowable power set by the means is temporarily increased, and when the excess output request is made when the calculated deterioration factor is equal to or greater than the limit start threshold, only when the internal combustion engine is started. Temporarily increasing discharge allowable power limited by the discharge limiting means;
(D) controlling the internal combustion engine, the electric motor, and the electric cranking means so that electric power discharged from the electric storage means is within a range of the discharge allowable electric power;
Is included.

  As in this method, when the deterioration factor is less than the limit start threshold and the discharge allowable power is not limited, the storage means is deteriorated by temporarily increasing the discharge allowable power in response to the excess output request. Therefore, it is possible to obtain power from the power output device with high responsiveness by effectively using the power from the power storage means. In addition, when the deterioration factor is equal to or greater than the limit start threshold and the discharge allowable power is limited, by temporarily increasing the discharge allowable power only when an excess output request accompanying the start request of the internal combustion engine is made, It is possible to suppress the deterioration of the power storage means due to the continuation of the discharge at a high current by setting the excessive output from the power storage means exceeding the original (before temporary increase) discharge allowable power as a necessary minimum. Further, when the discharge allowable power is limited based on the deterioration factor, the internal combustion engine is improved in response to the start request by temporarily increasing the discharge allowable power only when the start request for the internal combustion engine is made. After the internal combustion engine is started, the current is reduced by suppressing the discharge from the power storage means while securing the required power, thereby reducing the deterioration of the power storage means due to the continuation of the discharge. It becomes possible to suppress. Therefore, according to this method, it is possible to suppress deterioration of the power storage means while more appropriately using the power from the power storage means.

  Next, the best mode for carrying out the present invention will be described using examples.

  FIG. 1 is a schematic configuration diagram of a hybrid vehicle 20 as a vehicle according to an embodiment of the present invention. A hybrid vehicle 20 shown in the figure is connected to an engine 22, a three-shaft power distribution and integration mechanism 30 connected to a crankshaft 26 that is an output shaft of the engine 22 via a damper 28, and the power distribution and integration mechanism 30. Motor MG1 capable of generating electricity, reduction gear 35 attached to ring gear shaft 32a as a drive shaft connected to power distribution and integration mechanism 30, and motor MG2 connected to ring gear shaft 32a via reduction gear 35 And an electronic control unit for hybrid (hereinafter referred to as “hybrid ECU”) 70 that controls the entire hybrid vehicle 20.

  The engine 22 is an internal combustion engine that outputs power when supplied with hydrocarbon-based fuel such as gasoline or light oil. The fuel injection amount or ignition timing by an engine electronic control unit (hereinafter referred to as “engine ECU”) 24, Control of intake air volume etc. The engine ECU 24 receives signals from various sensors that are provided for the engine 22 and detect the operating state of the engine 22. The engine ECU 24 communicates with the hybrid ECU 70 to control the operation of the engine 22 based on a control signal from the hybrid ECU 70, a signal from the sensor, and the like, and to transmit data on the operation state of the engine 22 as necessary. It outputs to ECU70.

  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 rotating elements. A crankshaft 26 of the engine 22 is connected to the carrier 34 as the engine side rotation element, a motor MG1 is connected to the sun gear 31, and a reduction gear 35 is connected to the ring gear 32 as the axle side rotation element via the ring gear shaft 32a. The power distribution and integration mechanism 30 distributes the power from the engine 22 input from the carrier 34 to the sun gear 31 side and the ring gear 32 side according to the gear ratio when the motor MG1 functions as a generator. When the motor functions as an electric motor, the power from the engine 22 input from the carrier 34 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 wheels 39a and 39b, which are drive wheels, via the gear mechanism 37 and the differential gear 38.

  Both the motor MG1 and the motor MG2 are configured as well-known synchronous generator motors that operate as generators and can operate as motors, and exchange power with the battery 50 that is a secondary battery via inverters 41 and 42. Do. The power line 54 connecting the inverters 41 and 42 and the battery 50 is configured as a positive bus and a negative bus shared by the inverters 41 and 42, and the power generated by one of the motors MG1 and MG2 is supplied to the other. It can be consumed with the motor. Therefore, the battery 50 is charged / discharged by the electric power generated from one of the motors MG1 and MG2 or the insufficient electric power. If the electric power balance is balanced by the motors MG1 and MG2, the battery 50 is charged. It will not be discharged. The motors MG1 and MG2 are both driven and controlled by a motor electronic control unit (hereinafter referred to as “motor ECU”) 40. The motor ECU 40 receives 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 detected phase current applied to the motors MG1 and MG2 is input, and the motor ECU 40 outputs a switching control signal and the like to the inverters 41 and 42. The motor ECU 40 executes a rotation speed calculation routine (not shown) based on signals input from the rotation position detection sensors 43 and 44, and calculates the rotation speeds Nm1 and Nm2 of the rotors of the motors MG1 and MG2. Further, the motor ECU 40 communicates with the hybrid ECU 70, controls the driving of the motors MG1, MG2 based on the control signal from the hybrid ECU 70, and transmits data related to the operating state of the motors MG1, MG2 to the hybrid ECU 70 as necessary. Output.

  The battery 50 is configured as a lithium ion secondary battery in the embodiment, and is managed by a battery electronic control unit (hereinafter referred to as “battery ECU”) 52. The battery ECU 52 includes signals necessary for managing the battery 50, such as an inter-terminal voltage Vb from the voltage sensor 53 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 installed current sensor 55, the battery temperature Tb from the temperature sensor 56 attached to the battery 50, and the like are input. Further, the battery ECU 52 outputs data related to the state of the battery 50 to the hybrid ECU 70 and the engine ECU 24 by communication as necessary. Further, in order to manage the battery 50, the battery ECU 52 calculates the remaining capacity SOC based on the integrated value of the charging / discharging current Ib detected by the current sensor 55, or charges the battery 50 based on the remaining capacity SOC. The power required for discharging the battery 50 and the input limit Win as the charge allowable power, which is the power allowed for charging the battery 50 based on the remaining charge SOC and the battery temperature Tb. The output limit Wout as the discharge allowable power is set. Here, the input / output limits Win and Wout of the battery 50 are basically the input limit correction coefficient or the output limit correction based on the remaining capacity SOC of the battery 50 to a value (temperature dependent value) based on the battery temperature Tb. It can be set by multiplying by a coefficient. As for the output limit Wout, in the embodiment, the output limit base value Woutb, which is the product of the temperature-dependent value and the output limit correction coefficient, is obtained, and the output limit base value Woutb is appropriately corrected to obtain the final output. The limit Wout is set. FIG. 2 shows an example of the relationship between the battery temperature Tb and the temperature dependence value of the output limitation, and FIG. 3 shows an example of the relationship between the remaining capacity SOC of the battery 50 and the output limitation correction coefficient.

  The hybrid ECU 70 is configured as a microprocessor centered on the CPU 72, and includes a ROM 74 for storing a processing program, a RAM 76 for temporarily storing data, an input / output port and a communication port (not shown), and the like in addition to the CPU 72. The hybrid ECU 70 detects the ignition signal from the ignition switch (start switch) 80, the shift position SP from the shift position sensor 82 that detects the shift position SP that is the operation position of the shift lever 81, and the depression amount of the accelerator pedal 83. The accelerator opening Acc from the accelerator pedal position sensor 84, the brake pedal stroke BS from the brake pedal stroke sensor 86 for detecting the depression amount of the brake pedal 85, the vehicle speed V from the vehicle speed sensor 87, and the like are input via the input port. . As described above, the hybrid ECU 70 is connected to the engine ECU 24, the motor ECU 40, the battery ECU 52, etc. via the communication port, and exchanges various control signals and data with the engine ECU 24, the motor ECU 40, the battery ECU 52, etc. ing.

  In the hybrid vehicle 20 of the embodiment configured as described above, a request 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. Torque is calculated, and engine 22, motor MG1, and motor MG2 are controlled so that power corresponding to the required torque is output to ring gear shaft 32a. As the operation control mode of the engine 22, the motor MG1, and the motor MG2, the engine 22 is operated and controlled so that power corresponding to the required torque is output from the engine 22, and all of the power output from the engine 22 is a power distribution integration mechanism. 30, a 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 the power corresponding to the sum is output from the engine 22, and all or a part of the power output from the engine 22 with charge / discharge of the battery 50 is the power distribution integration mechanism 30 and the motor MG1. The required power is ringed with torque conversion by the motor MG2 A charge / discharge operation mode in which the motor MG1 and the motor MG2 are driven and controlled so as to be output to the gear shaft 32a, and a motor which controls the operation so that the operation of the engine 22 is stopped and power corresponding to the request is output from the motor MG2 to the ring gear shaft 32a There are operation modes.

  Further, in the hybrid vehicle 20 of the embodiment, when a predetermined condition is satisfied under the torque conversion operation mode or the charge / discharge operation mode, intermittent operation for automatically stopping and starting the engine 22 is executed. In the embodiment, for example, the cooling water temperature of the engine 22 is equal to or higher than a first predetermined temperature (for example, 55 ° C. to 65 ° C.), the remaining capacity SOC of the battery 50 is within a predetermined management area, and the accelerator pedal 83 is depressed. When the required vehicle power set in accordance with the amount becomes less than a first threshold value Pref1 (for example, 2 kW to 10 kW), the automatic stop condition of the engine 22 is established, and the engine 22 is automatically stopped and the torque conversion operation mode or charge / discharge is performed. Transition from operation mode to motor operation mode. Further, for example, when the required power set in response to the depression of the accelerator pedal 83 becomes greater than or equal to a second threshold value Pref2 (for example, 4 to 15 kW) that is larger than the first start threshold value under the motor operation mode. When the automatic start condition of the engine 22 is satisfied and the engine start process with cranking by the motor MG1 is executed, the stopped engine 22 is restarted.

  By the way, the battery 50 mounted in the hybrid vehicle 20 of the embodiment is a lithium ion secondary battery. However, when the discharge at a high current is continued for the lithium ion secondary battery, the inter-terminal voltage Vb is It has been found that even if the lower limit voltage, which is the lower limit of the voltage range in which the battery performance can be sufficiently exhibited, has not been reached, deterioration starts. That is, in the lithium ion secondary battery, when discharging at a relatively high (constant) current value is continued, the inter-terminal voltage Vb becomes relatively steep with time from a certain timing as shown in FIG. It has the characteristic that it falls. Based on this, in the embodiment, it is assumed that the deterioration of the battery 50 starts from the timing (deterioration start timing) at which the inter-terminal voltage Vb decreases relatively rapidly with time, and the following equation (1): It is assumed that the deterioration start timing does not arrive unless the deterioration factor D expressed by the differential equation exceeds a predetermined reference value. Here, if the Laplace transform of both sides of Formula (1) is taken, the transfer function shown in the following Formula (2) can be obtained. However, “α” and “β” in the equations (1) and (2) are both parameters depending on the battery temperature Tb and the remaining capacity SOC. As can be seen from the equation (2), the deterioration factor D is determined by the coefficients α and β, that is, the coefficient κ determined based on the battery temperature Tb and the remaining capacity SOC, and the charge / discharge current Ib, as shown in the following equation (3). It can be obtained as a product of the integrated value, and becomes larger as the discharge of the battery 50 at a high current continues. Conversely, when the battery 50 is charged, it gradually decreases. In the embodiment, a restriction start threshold value (control target value) Dtag smaller than the reference value is set for the deterioration factor D thus obtained, and the restriction start threshold value is set when the deterioration factor D becomes equal to or greater than the restriction start threshold value Dtag. The output limit Wout is set according to the following equation (4) by feedback control (PI control) based on the deviation between Dtag and the degradation factor D, whereby the degradation start timing of the battery 50 is maintained while maintaining the degradation factor D below the reference value. It was decided not to arrive. In Equation (4), “Kp” on the right side is the gain of the proportional term, and “Ki” on the right side is the gain of the integral term. In the embodiment, the relationship among the battery current Tb, the remaining capacity SOC, and the coefficient κ is determined in advance and stored in the ROM 74 as a coefficient setting map. The coefficient κ is a battery given when calculating the deterioration factor D. A value corresponding to the temperature Tb and the remaining capacity SOC is derived and set from the map. In the embodiment, the setting process of the output limit Wout is executed by the battery ECU 52. Basically, the output limit Wout (charge / discharge current Ib) is set smaller as the deviation between the limit start threshold Dtag and the deterioration factor D increases. It will be. A block diagram of the control system related to the setting of the output limit Wout by the battery ECU 52 is shown in FIG. In the embodiment, the limitation on the output limit Wout based on the above-described degradation factor D is executed until the degradation factor D falls below a predetermined threshold value that is smaller than the limitation start threshold value Dtag.

dD / dt + α · D = β · Ib (1)
D = (β / α) / (s / α + 1) · £ {Ib} (2)
D = κ ・ ∫Ib ・ dt (3)
Wout = Woutb + Kp · (Dtag-D) + Ki · ∫ (Dtag-D) · dt… (4)

  Further, the procedure for setting the limit start threshold value Dtag and gain related to the above equation (4) will be described. From the transfer function shown in equation (2), as shown in FIG. 5, the deterioration factor D is a unit step of the discharge current Ib. Since it converges to the value β / α with a time constant 1 / α with respect to the input, if the discharge at Ib = α / β is continued, the deterioration factor D converges to the value 1.0. Based on this, in the embodiment, the reference value for the degradation factor D is set to a value of 1.0, and the limit start threshold Dtag and the gain are set. Here, if the deterioration factor D converges to the reference value 1.0, the charge / discharge current Ib is Ib = α / β = Ib_D1, and the battery voltage Vb at this time is Vb = Vb_D1, The electric power Pb_D1 of the battery 50 at this time is Pb_D1 = Ib_D1 × Vb_D1. If the integral term in the above equation (4) is ignored in consideration of responsiveness, the relationship shown in the following equation (5) is established when the deterioration factor D converges to the value 1.0 as the reference value. (See FIG. 6). Further, if both sides of the above equation (4) are differentiated with respect to time (where Woutb, Dtag, kp, Ki are fixed values), the following equation (6) is obtained. Considering that the time change rate is smaller than the time change rate of the proportional term, ignoring the second term on the right side of the equation (6) and using the above equation (1), the relationship of the following equation (7) is obtained. be able to. From equation (7), it can be seen that the time change rate dWout / dt of the output limit Wout increases toward the negative side as the value of the deterioration factor D decreases and as the value of the charge / discharge current Ib increases as the discharge current. Therefore, if the limit value of the time change rate dWout / dt of the output limit Wout determined from the drivability of the hybrid vehicle 20 is ΔWout, dWout / dt = ΔWout when the deterioration factor D reaches the limit start threshold Dtag. Therefore, the restriction start threshold value Dtag and the proportional term gain Kp need only satisfy the following expression (8). Therefore, if the above formulas (5) and (8) are used as constraint conditions, the limit start threshold Dtag and the proportional term gain Kp are set using other parameters such as coefficients α and β that are separately determined through experiments and analysis. Can be determined. If at least the proportional term Kp is determined, the output limit Wout is gradually increased by setting the output limit Wout by the feedback control according to the above formula (4) from the time when the deterioration factor D becomes equal to or greater than the limit start threshold Dtag. Accordingly, as shown in FIG. 7, the deterioration factor D can be converged to a value of 1 so that the deterioration start timing of the battery 50 does not arrive. Further, after setting the integral term gain Ki as appropriate (for example, Ki = 1.0) and setting the output limit Wout by feedback control according to the above equation (4), the deterioration factor D approaches the value 1. Thus, it becomes possible to more surely suppress the deterioration start timing of the battery 50 from decreasing gradually.

Wout = Woutb + Kp ・ (Dtag-1.0) = Pb_D1 (5)
dWout / dt = -Kp · dD / dt + Ki · (Dtag-D) (6)
dWout / dt = -Kp · dD / dt = -Kp · (-α · D + β · Ib) (7)
ΔWout = -Kp ・ (-α ・ D tag + β ・ Ib_woutb) (8)

  Next, the operation of the hybrid vehicle 20 configured as described above will be described. FIG. 9 is a flowchart illustrating an example of a drive control routine executed by the hybrid ECU 70 of the embodiment. This routine is repeatedly executed every predetermined time (for example, every several milliseconds) when the accelerator pedal 83 is depressed by the driver of the hybrid vehicle 20.

  At the start of the drive control routine of FIG. 9, the CPU 72 of the hybrid ECU 70 determines the accelerator opening Acc from the accelerator pedal position sensor 84, the vehicle speed V from the vehicle speed sensor 87, the rotational speeds Nm1, Nm2 of the motors MG1, MG2, and the battery 50. Data input processing necessary for control, such as charge / discharge required power Pb * and input / output limits Win and Wout, which are power allowed for charging / discharging of the battery 50, is executed (step S100). Here, the rotational speeds Nm1 and Nm2 of the motors MG1 and MG2 are input from the motor ECU 40 by communication. The charge / discharge required power Pb * and the input / output limits Win and Wout of the battery 50 are input from the battery ECU 52 by communication. As can be seen from FIG. 8, in the embodiment, a value obtained by limiting the base value Pbb of the charge / discharge required power set based on the remaining capacity SOC by the input limit Win and the output limit Wout is the charge / discharge required power Pb *. Will be set as After the data input process in step S100, it is determined whether or not the input accelerator opening Acc is equal to or greater than a predetermined threshold value Aref (step S110). If the accelerator opening Acc is greater than or equal to the threshold value Aref in step S110, it is recognized that the driving force (torque) request degree (acceleration request degree) by the driver is relatively large, and therefore the output to the battery 50 side. An excess output request flag Fout1 for requesting a temporary increase of the limit Wout is set to a value 1 (step S120). In the embodiment, the threshold value Aref is set to a value such as 70% or 80%, for example. If it is determined in step S110 that the accelerator opening degree Acc is less than the threshold value Aref, the process of step S120 is skipped.

  After the processing in step S110 or S120, the required torque Tr * to be output to the ring gear shaft 32a as the drive shaft connected to the wheels 39a and 39b as the drive wheels is set based on the accelerator opening Acc and the vehicle speed V. Then, the required power P * required for the entire vehicle is set (step S130). In the embodiment, the relationship among the accelerator opening Acc, the vehicle speed V, and the required torque Tr * is determined in advance and stored in the ROM 74 as a required torque setting map. The required torque Tr * is the given accelerator opening. The one corresponding to Acc and the vehicle speed V is derived and set from the map. FIG. 10 shows an example of the required torque setting map. In the embodiment, the required power P * is calculated as the sum of the set required torque Tr * multiplied by the rotation speed Nr of the ring gear shaft 32a, the charge / discharge required power Pb *, and the loss Loss. The rotational speed Nr of the ring gear shaft 32a can be obtained by dividing the rotational speed Nm2 of the motor MG2 by the gear ratio Gr of the reduction gear 35 as shown in the figure or by multiplying the vehicle speed V by the conversion factor k. If the required power P * is set, it is determined whether or not the set required power P * is equal to or greater than the first threshold value Pref1 (step S140), and if the required power P * is equal to or greater than the first threshold value Pref1. If so, it is further determined whether or not the engine 22 is in operation (step S150). When the engine 22 is in operation, the target rotational speed Ne * and the target torque Te * of the engine 22 are set based on the required power P * so that the required power P * is output to the engine 22 (step). S160). In the embodiment, the target rotational speed Ne * and the target torque Te * of the engine 22 are set based on a predetermined operation line for efficiently operating the engine 22 and the required power Pe *. FIG. 11 illustrates an operation line of the engine 22 and a correlation curve between the target rotational speed Ne * and the target torque Te *. 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 the correlation curve indicating that the required power Pe * (Ne * × Te *) is constant. .

  When the target rotational speed Ne * and the target torque Te * of the engine 22 are thus set, the target rotational speed Ne *, the rotational speed Nr (Nm2 / Gr) of the ring gear shaft 32a set in step S160, and the power distribution and integration mechanism The target rotational speed Nm1 * of the motor MG1 is calculated according to the following equation (9) using the gear ratio ρ of 30 (the number of teeth of the sun gear 31 / the number of teeth of the ring gear 32), and the calculated target rotational speed Nm1 * The calculation of Expression (10) based on the current rotation speed Nm1 is executed to set the torque command Tm1 * for the motor MG1 (step S170). Here, Expression (9) is a dynamic relational expression regarding the rotating element of the power distribution and integration mechanism 30. FIG. 12 illustrates a collinear diagram showing a dynamic relationship between the rotation speed and torque in the rotating elements of the power distribution and integration mechanism 30. In the figure, the left S-axis indicates the rotational speed of the sun gear 31 that matches the rotational speed Nm1 of the motor MG1, the central C-axis indicates the rotational speed of the carrier 34 that matches the rotational speed Ne of the engine 22, and the right R-axis. The axis indicates the rotational speed Nr of the ring gear 32 obtained by dividing the rotational speed Nm2 of the motor MG2 by the gear ratio Gr of the reduction gear 35. Further, two thick arrows on the R axis indicate that the torque acting on the ring gear shaft 32a by this torque output when the torque Tm1 is output from the motor MG1 and the torque Tm2 output from the motor MG2 via the reduction gear 35. The torque acting on the ring gear shaft 32a is shown. Expression (9) for obtaining the target rotational speed Nm1 * of the motor MG1 can be easily derived by using the rotational speed relationship in this alignment chart. Expression (10) is a relational expression in feedback control for rotating the motor MG1 at the target rotation speed Nm1 *. In Expression (10), “k1” in the second term on the right side is a gain of the proportional term. “K2” in the third term on the right side is the gain of the integral term.

Nm1 * = Ne * ・ (1 + ρ) / ρ-Nm2 / (Gr ・ ρ) (9)
Tm1tmp = -ρ / (1 + ρ) ・ Te * + k1 ・ (Nm1 * -Nm1) + k2 ・ ∫ (Nm1 * -Nm1) dt (10)

  If torque command Tm1 * of motor MG1 is set, it is obtained as the product of input / output limits Win and Wout of battery 50, torque command Tm1 * of motor MG1 set in S170, and current rotation speed Nm1 of motor MG1. The torque limits Tmin and Tmax as upper and lower limits of the torque that may be output from the motor MG2 by dividing the deviation from the power consumption (generated power) of the motor MG1 by the rotational speed Nm2 of the motor MG2 And it calculates according to Formula (12) (step S180). Further, a temporary motor torque Tm2tmp as a torque to be output from the motor MG2 using the required torque Tr *, the torque command Tm1 *, the gear ratio ρ of the power distribution and integration mechanism 30 and the gear ratio Gr of the reduction gear 35 is expressed by the following formula ( 13) (step S190), and the torque command Tm2 * of the motor MG2 is set as a value obtained by limiting the temporary motor torque Tm2tmp with the torque limits Tmin and Tmax calculated in step S180 (step S200). By setting the torque command Tm2 * of the motor MG2 in this way, the torque output to the ring gear shaft 32a as the drive shaft can be set as a torque that is limited within the range of the input / output limits Win and Wout of the battery 50. it can. Equation (13) can be easily derived from the alignment chart of FIG. When the target rotational speed Ne * and target torque Te * of the engine 22 and the torque commands Tm1 * and Tm2 * of the motors MG1 and MG2 are thus set, the target rotational speed Ne * and the target torque Te * of the engine 22 are transferred to the engine ECU 24 and the motor. Torque commands Tm1 * and Tm2 * of MG1 and MG2 are transmitted to the motor ECU 40 (step S210), and this routine is temporarily terminated. The engine ECU 24 that has received the target rotational speed Ne * and the target torque Te * executes control for obtaining the target rotational speed Ne * and the target torque Te *. Receiving the torque commands Tm1 * and Tm2 *, the motor ECU 40 controls the switching elements of the inverters 41 and 42 so that the motor MG1 is driven according to the torque command Tm1 * and the motor MG2 is driven according to the torque command Tm2 *. Do.

Tmin = (Win-Tm1 * ・ Nm1) / Nm2 (11)
Tmax = (Wout-Tm1 * ・ Nm1) / Nm2 (12)
Tm2tmp = (Tr * + Tm1 * / ρ) / Gr (13)

  If it is determined in step S150 that the engine 22 is not operating, it is determined whether the required power P * is equal to or greater than the second threshold value Pref2 (step S220), and the required power P *. Is equal to or greater than the second threshold value Pref2, the engine start flag Fes is set to a value 1 to indicate the execution of an unillustrated engine start time drive control routine (starting process of the engine 22) (step S230), and the motor MG1. In addition, the excess output request flag Fout2 for requesting the battery 50 to temporarily increase the output limit Wout is set to a value of 1 so that the engine 22 using the MG2 can be started well and quickly with less shock. Setting is made (step S240), and this routine is terminated. Here, the engine start time drive control routine starts the engine 22 while cranking the engine 22 by the motor MG1 while discharging from the battery 50, and acts on the ring gear shaft 32a as the engine 22 is cranked. This is a process for driving the motor MG2 so that torque based on the required torque Tr * is output to the ring gear shaft 32a while canceling torque as a reaction force against the driving torque. When the engine starting driving control routine is completed, the engine is started. The flag is set to the value 0. In the embodiment, the threshold value Pref2 used in step S220 is determined based on the characteristics of the engine 22 and the motor MG2, and the lower limit power in a region where the engine 22 can be efficiently operated or a value in the vicinity thereof. It is said. If it is determined in step S220 that the required power P * is less than the second threshold value Pref2, the target rotational speed Ne * and the target torque Te * of the engine 22 are set to values 0 ( In step S270), the torque command Tm1 * of the motor MG1 is set to 0 (step S280), and then the processes in steps S180 to S210 described above are executed.

  On the other hand, if it is determined in step S140 that the required power P * is less than the threshold value Pref1, it is determined whether or not the engine 22 is in operation (step S250). In this case, if the engine 22 is operating, the target rotational speed Ne * of the engine 22 is set to a predetermined rotational speed Nidl so that the engine 22 can operate independently without substantially outputting torque. Torque Te * is set to a value 0 (step S260). In the embodiment, the rotation speed Nidl is, for example, the rotation speed during idling (800 to 1000 rpm). On the other hand, if the engine 22 is not operating, the target rotational speed Ne * and the target torque Te * of the engine 22 are set to 0 (step S270). Then, after setting the torque command Tm1 * of the motor MG1 to a value of 0 (step S280), the processes of steps S180 to S210 described above are executed.

  As described above, in the hybrid vehicle 20 of the embodiment, when the accelerator opening degree Acc is equal to or greater than the threshold value Aref and the required degree of torque with respect to the ring gear shaft 32a as the drive shaft is equal to or greater than a predetermined degree, the excess output request flag Fout1 is a value of 1. (Step S120). Further, when the required power P * is equal to or greater than the second threshold value Pref2 and the engine start flag is set to a value 1 while the engine 22 is stopped, the excess output request flag Fout2 is set to a value 1 (step S240). . In the hybrid vehicle 20 of the embodiment, the battery ECU 52 sets the output limit Wout of the battery 50 based on the battery temperature Tb, the remaining capacity SOC, and the deterioration factor D, and is set by the hybrid ECU 70 as described above. The output limit Wout of the battery 50 is temporarily increased as appropriate according to the values of the excess output request flags Fout1 and Fout2. The procedure for setting the output limit Wout of the battery 50 by the battery ECU 52 will be described with reference to FIG. FIG. 13 is a flowchart illustrating an example of an output limit setting routine executed by the battery ECU 52 of the embodiment. This routine is repeatedly executed every predetermined time when the ignition switch 80 is turned on by the driver.

  At the start of the output limit setting routine, the CPU (not shown) of the battery ECU 52 performs a battery temperature Tb from the temperature sensor 56, a terminal voltage Vb from the voltage sensor 53, a charge / discharge current Ib from the current sensor 55, a remaining capacity SOC, Input processing of data necessary for control such as the deterioration factor D, the restriction start threshold Dtag, and the excess output request flags Fout1 and Fout2 from the hybrid ECU 70 is executed (step S300). After the data input process in step S300, a map that defines the relationship between the battery temperature Tb and the temperature-dependent value (see FIG. 2) and the relationship between the remaining capacity SOC and the output limiting correction coefficient (see FIG. 3) are defined. Using the map, output limit base value Woutb based on battery temperature Tb and remaining capacity SOC is set (step S310). Next, it is determined whether or not the predetermined flag F set to the value 1 is 0 when the output limit Wout is restricted based on the deterioration factor D and the restriction start threshold Dtag (step S320). . If the flag F is 0, the restriction start threshold Dtag input in step S300 is set as the control threshold Dref (step S330). If the flag F is 1, the predetermined restriction start threshold Dtag is determined from the input. A value obtained by subtracting the value ΔD is set as a control threshold value Dref (step S340).

  If the control threshold value Dref is set based on the restriction start threshold value Dtag in step S330 or S340, it is determined whether or not the deterioration factor D input in step S300 is less than the threshold value Dref (step S350). If the input degradation factor D is less than the threshold value Dref, the flag F is set to 0 (step S360), and the output limit base value Woutb set in step S310 is set as the output limit Wout as it is ( Step S370). In this way, when the output restriction base value Woutb is set as the output restriction Wout as it is in step S370 without performing the restriction of the output restriction Wout based on the deterioration factor D and the restriction start threshold Dtag, in step S300 It is determined whether or not the input excess output request flag Fout1 is a value 1 (step S380), and the excess output request flag Fout1 is set to a value 1 due to an increase in the degree of request for driving force (acceleration request). If so, it is determined whether or not a predetermined time t1 has elapsed since the output limit Wout of the battery 50 was temporarily increased (step S390). If the predetermined time t1 has elapsed from the previous temporary increase in the output limit Wout, it is determined whether or not the elapsed time since the temporary increase in the current output limit Wout is less than the predetermined time t0. (Step S400) If the elapsed time is equal to or shorter than the predetermined time t0, a value obtained by adding the predetermined value ΔW to the output limit Wout set in Step S370 is reset as a new output limit Wout (Step S410). On the other hand, if a negative determination is made in step S390 or S400, the excess output request flag Fout1 is set to 0 (step S420), and the output limit Wout set in step S370 is reset. Without again, the processing after step S300 is executed again. If it is determined in step S380 that the excess output request flag Fout1 input in step S300 is 0, whether or not the excess output request flag Fout2 input in step S300 is 1 is determined. Determination is made (step S430). If the excess output request flag Fout2 is set to the value 1 due to the start request of the engine 22, whether or not the predetermined time t2 has elapsed since the output limit Wout of the battery 50 was temporarily increased last time. Is determined (step S440). If the predetermined time t2 has elapsed from the previous temporary increase in the output limit Wout, it is determined whether or not the elapsed time since the temporary increase in the current output limit Wout is less than the predetermined time t0. (Step S450) If the elapsed time is equal to or shorter than the predetermined time t0, a value obtained by adding the predetermined value ΔW to the output limit Wout set in Step S370 is reset as a new output limit Wout (Step S410). On the other hand, if a negative determination is made in step S430, S440 or S450, the excess output request flag Fout2 is set to 0 (step S460), and the output limit Wout set in step S370 is set. The process after step S300 is executed again without resetting.

  On the other hand, when it is determined in step S350 that the deterioration factor D is equal to or greater than the threshold value Dref, the flag F is set to 1 (step S470), and the output limit Wout is set according to the above equation (4). (Step S480). Thus, when the output limit Wout is limited based on the deterioration factor D and the limit start threshold Dtag, the excess output request input immediately in step S300 is performed without executing the determination for the excess output request flag Fout1. It is determined whether or not the flag Fout2 is a value 1 (step S430). If the excess output request flag Fout2 is set to the value 1 due to the start request of the engine 22, and an affirmative determination is made in steps S440 and S450, the output limit Wout set in step S480. A value obtained by adding the predetermined value ΔW to the value is reset as a new output limit Wout (step S410). That is, when the output limit Wout is limited based on the deterioration factor D and the limit start threshold Dtag, the excess output request flag Fout2 is set to the value 1 as the automatic start condition of the engine 22 is established while the engine 22 is stopped. Only when it is set, a temporary increase in the output limit Wout is allowed. Note that ΔWout, which is a temporary increase of the output limit Wout, is, for example, electric power required for cranking for starting the engine 22 by the motor MG1 when the engine starting drive control routine is executed once (for example, about 5 kW). ) And the power required to output the power from the motor MG2 and continue running (for example, about 1 kW). Further, a step regarding the time t1 as a threshold used in step S390 for the excess output request flag Fout1 based on the accelerator opening Acc (requested torque Tr *) by the driver and the excess output request flag Fout2 based on the start request of the engine 22 is performed. By making the time t2 as the threshold used in S440 different, it becomes possible to temporarily increase the output limit Wout of the battery 50 more appropriately while suppressing the heat generation of the battery 50 and the like.

  As described above, in the hybrid vehicle 20 of the embodiment, when the battery ECU 52 exceeds a predetermined reference value (value 1.0 in the embodiment) based on the value of the current Ib flowing through the battery 50, the battery 50 is deteriorated. A deterioration factor D indicating that is started is calculated. In addition, the battery ECU 52 sets an output limit Wout that is electric power allowed for discharging the battery 50 based on the state of the battery 50, that is, the battery temperature Tb and the remaining capacity SOC, and the deterioration factor D is smaller than the reference value. The output limit Wout is limited so that the degradation factor D is equal to or less than the reference value when the threshold value is equal to or greater than the limit start threshold Dtag (step S480 in FIG. 13). Then, when the excess output request flag Fout1 or Fout2 is set to a value 1 when the deterioration factor D is less than the threshold value Dref based on the restriction start threshold value Dtag, the battery ECU 52 outputs the battery 50 as discharge allowable power. Limit Wout is temporarily increased (step S410 in FIG. 13), and hybrid ECU 70, engine ECU 24, and motor ECU 40 cause engine 22 and motor MG1 to stay within the output limit Wout within the range of output limit Wout. And MG2 are controlled (steps S180 to S210 in FIG. 9). Further, when the excess output request flag Fout1 or Fout2 is set to the value 1 when the deterioration factor D is equal to or greater than the threshold Dref based on the limit start threshold Dtag, only the excess output request flag Fout2 is set to the value 1. When the engine 22 is started, that is, only when the engine 22 is started, the output limit Wout limited based on the deterioration factor D and the limit start threshold Dtag is temporarily increased (step S410 in FIG. 13), and the hybrid ECU 70 and the engine ECU 24 The motor ECU 40 controls the engine 22 and the motors MG1 and MG2 while keeping the electric power discharged from the battery 50 within the range of the output limit Wout (steps S180 to S210 in FIG. 9). As described above, when the deterioration factor D is less than the threshold value Dref based on the limit start threshold value Dtag and the output limit Wout is not limited, the output limit of the battery 50 is set when the excess output request flag Fout1 or Fout2 is set to the value 1. Wout is temporarily increased, so that power (torque) can be obtained with good responsiveness by effectively using the power of the battery 50 without deteriorating the battery 50. When the deterioration factor D is equal to or greater than the threshold value Dref based on the restriction start threshold value Dtag and the output restriction Wout is restricted based on the deterioration factor D and the restriction start threshold value Dtag, the engine 22 is automatically stopped when the engine 22 is stopped. By temporarily increasing the output limit Wout only when the excess output request flag Fout2 is set to a value 1 with the establishment of the start condition, the output limit Wout of the battery 50 is temporarily increased, that is, from the battery 50. It is possible to suppress deterioration of the battery 50 due to continuation of discharge at a high current by setting an excess output exceeding the original (preliminary increase) output limit as a necessary minimum. Further, when the output limit Wout is limited based on the deterioration factor D and the limit start threshold Dtag, the engine 22 is started by temporarily increasing the super output limit Wout as the automatic start condition of the engine 22 is satisfied. Upon request, the engine 22 can be started well and quickly with fewer shocks. After the engine 22 is started, the discharge from the battery 50 is suppressed while securing the required torque Tr *, and the charge / discharge current Ib Thus, it is possible to suppress the deterioration of the battery 50 due to the continuation of discharge. Therefore, in the hybrid vehicle 20 of the embodiment, it is possible to suppress the deterioration of the battery 50 while more appropriately using the electric power from the battery 50.

  Further, as in the above-described embodiment, when the output limit Wout of the battery 50 is temporarily increased, if the output limit Wout is increased by a predetermined amount ΔW for a predetermined time t0, the battery 50 is prevented from deteriorating. This makes it possible to make the excess output exceeding the original output limit (before temporary increase) more appropriate. Further, as in the above embodiment, when the deterioration factor D is less than the threshold value Dref based on the limit start threshold value Dtag and the output limit Wout is not limited, the engine 22 is started or the ring gear shaft 32a as the drive shaft is driven. When the required level of force (torque) is greater than or equal to a predetermined level, the hybrid vehicle can obtain power with good responsiveness by allowing an excess output from the battery 50 to exceed the original output limit (before temporary increase). It is possible to improve the running performance of 20. Further, as in the above-described embodiment, when the deterioration factor D is equal to or greater than the limit start threshold Dtag smaller than the reference value (value 1.0), the battery 50 is set so that the deterioration factor D becomes equal to or less than the reference value 1.0. By setting the output limit Wout, which is the power allowed for the discharge, it is possible to more reliably suppress the deterioration of the battery 50 due to the continuation of the discharge at a particularly high current. At this time, if the output limit Wout is made smaller as the deviation between the limit start threshold Dtag and the deterioration factor D is larger, the discharge from the battery 50 can be more appropriately limited. Furthermore, if the deterioration factor D is a value based on the integrated value of the current Ib flowing through the battery 50, the deterioration factor D can be calculated as a more appropriate indication of the degree of deterioration of the battery 50. In this way, the process of limiting the output limit Wout of the battery 50 based on the deterioration factor D is such that the terminal voltage Vb reaches the lower limit voltage when discharging at a high current as in the lithium ion secondary battery is continued. It is particularly suitable for the battery 50 having the characteristic that it starts to deteriorate even if it is not. However, since the deterioration factor D can be calculated for other types of batteries 50 such as nickel-hydrogen secondary batteries other than lithium ion secondary batteries, the battery 50 of the hybrid vehicle 20 is not a lithium ion secondary battery. It goes without saying that other types may be used.

  In the hybrid vehicle 20, the ring gear shaft 32a serving as the drive shaft and the motor MG2 are connected via the reduction gear 35 that reduces the rotational speed of the motor MG2 and transmits it to the ring gear shaft 32a. Instead of this, for example, a transmission that has two shift stages of Hi and Lo, or three or more shift stages, and changes the rotation speed of the motor MG2 and transmits it to the ring gear shaft 32a may be employed. Moreover, although the hybrid vehicle 20 decelerates the power of the motor MG2 by the reduction gear 35 and outputs it to the ring gear shaft 32a as a drive shaft, the application target of the present invention is not limited to this. That is, according to the present invention, as in a hybrid vehicle 120 as a modified example shown in FIG. 14, the power of the motor MG2 is connected to the ring gear shaft 32a (the axle to which the wheels 39a and 39b as drive wheels are connected). May be applied to those that output to different axles (axles connected to the wheels 39c, 39d in FIG. 14). Furthermore, the hybrid vehicle 20 of the embodiment outputs the power of the engine 22 to the ring gear shaft 32a as a drive shaft connected to the wheels 39a and 39b as drive wheels via the power distribution and integration mechanism 30. The application target of the present invention is not limited to this. That is, the present invention provides a drive shaft that outputs power to the inner rotor 232 connected to the crankshaft 26 of the engine 22 and the wheels 39a and 39b as drive wheels, like a hybrid vehicle 220 as a modified example shown in FIG. And an outer rotor 234 connected to the motor, and may be applied to a motor provided with a counter-rotor motor 230 that transmits a part of the power of the engine 22 to the drive shaft and converts the remaining power into electric power. In addition, the present invention is capable of cranking the engine using power from the battery, an engine capable of outputting power for traveling, a motor capable of exchanging power with the battery and outputting power for traveling, and the battery. The present invention may be applied to a hybrid vehicle including a simple cell motor.

  Here, the correspondence between the main elements of the above-described embodiments and modifications and the main elements of the invention described in the column of means for solving the problems will be described. That is, in the above embodiment, the engine 22 that can output power to the ring gear shaft 32a corresponds to an “internal combustion engine”, and the motor MG2 that can output power to the ring gear shaft 32a corresponds to an “electric motor”. The motor MG1 capable of performing cranking for starting corresponds to “electric cranking means”, the battery 50 capable of exchanging electric power with the motors MG1 and MG2 corresponds to “power storage means”, and the charge / discharge current of the battery 50 A battery ECU 52 that calculates a deterioration factor D indicating that the deterioration of the battery 50 starts when a predetermined reference value is exceeded based on Ib corresponds to the “deterioration factor calculation means”, and the battery temperature Tb and the remaining capacity SOC The battery ECU 52 that sets the battery output limit Wout based on the The battery ECU 52 that executes the process of limiting the output limit Wout based on the deterioration factor D corresponds to the “discharge limiting means”, and the battery ECU 52 that executes the output limit setting routine of FIG. The combination of the hybrid ECU 70 that executes the drive control routine of FIG. 9, the engine ECU 24 that controls the engine 22, and the motor ECU 40 that controls the motors MG1 and MG2 corresponds to “control means”. The motor MG1 and the power distribution integration mechanism 30 and the counter-rotor motor 230 correspond to “power power input / output means”, the motor MG1 and the counter-rotor motor 230 correspond to “the power generation motor”, and the power distribution integration mechanism 30 This corresponds to “3-axis power input / output means”.

  The “internal combustion engine” is not limited to the engine 22 that outputs power by receiving a hydrocarbon-based fuel such as gasoline or light oil, and may be of any other type such as a hydrogen engine. The “motor” is not limited to the synchronous generator motor such as the motor MG2, and may be any other type such as an induction motor. “Electric cranking means” is not limited to the one that can also function as a generator such as the motor MG1, and may only perform cranking of the engine such as a cell motor. The “deterioration factor calculation means” is a battery ECU that calculates a deterioration factor indicating that the deterioration of the power storage means is started when a predetermined reference value is exceeded based on the value of the current flowing through the power storage means. Any other type other than the above may be used. The “discharge allowable power setting means” is of any type other than the battery ECU 52 as long as it sets discharge allowable power that is power allowed for discharging of the power storage means based on the state of the power storage means. It doesn't matter. The “discharge limiting means” is a discharge allowable power set by the discharge allowable power setting means at least when a predetermined excess output request made when starting the internal combustion engine is made when the deterioration factor is less than the limit start threshold. If the excess output is requested when the deterioration factor is equal to or greater than the limit start threshold, the allowable discharge power limited by the discharge limiting means is temporarily increased only when the internal combustion engine is started. Any type other than the battery ECU 52 may be used. As long as the “control means” controls the internal combustion engine, the electric motor, and the electric cranking means so that the electric power discharged from the electric storage means is within the range of the allowable discharge power, the hybrid ECU 70, the engine ECU 24, and the motor Any type other than the combination with the ECU 40 may be used. In any case, the correspondence between the main elements of the embodiments 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. This is an example for specifically describing the best mode for carrying out the invention, and does not limit the elements of the invention described in the column of means for solving the problem. In other words, the examples are merely specific examples of the invention described in the column of means for solving the problem, and the interpretation of the invention described in the column of means for solving the problem is described in the description of that column. Should be done on the basis.

  The embodiments of the present invention have been described above using the embodiments. However, the present invention is not limited to the above embodiments, and various modifications can be made without departing from the scope of the present invention. Needless to say.

  The present invention can be used in a power output apparatus, a vehicle manufacturing industry, and the like.

1 is a schematic configuration diagram of a hybrid vehicle 20 as a vehicle according to an embodiment of the present invention. It is explanatory drawing which shows an example of the relationship between battery temperature Tb and the temperature dependence value of the output limitation of the battery 50. FIG. It is explanatory drawing which shows an example of the relationship between the remaining capacity SOC of the battery 50, and the output limiting correction coefficient. 4 is an explanatory diagram illustrating characteristics of a battery 50. FIG. It is explanatory drawing which illustrates the response of the degradation factor D with respect to the unit step input of the electric current Ib. It is explanatory drawing which illustrates transition of the output restriction | limiting Wout when the output restriction | limiting Wout is restrict | limited based on the degradation factor D. It is explanatory drawing which illustrates transition of the degradation factor D when the output restriction | limiting Wout is restrict | limited based on the degradation factor D. FIG. It is a block diagram of a control system related to the setting of the output limit Wout by the battery ECU 52. It is a flowchart which shows an example of the drive control routine performed by hybrid ECU70 of an Example. It is explanatory drawing which shows an example of the map for request | requirement torque setting. It is explanatory drawing which illustrates the operation line of the engine 22, the correlation curve of target rotational speed Ne *, and target torque Te *. 3 is an explanatory diagram showing an example of a collinear diagram showing a dynamic relationship between the number of rotations and torque in a rotating element of the power distribution and integration mechanism 30. FIG. It is a flowchart which shows an example of the output restriction setting routine performed by battery ECU52 of an Example. It is a schematic block diagram of the hybrid vehicle 120 which concerns on a modification. FIG. 10 is a schematic configuration diagram of a hybrid vehicle 220 according to another modification.

Explanation of symbols

  20, 120, 220 Hybrid vehicle, 22 engine, 24 engine electronic control unit (engine ECU), 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, 37 gear mechanism, 38 differential gear, 39a, 39b, 39c, 39d wheels, 40 electronic control unit for motor (motor ECU), 41, 42 inverter, 43, 44 rotational position detection sensor, 50 battery, 52 Electronic control unit for battery (battery ECU), 53 voltage sensor, 54 power line, 55 current sensor, 56 temperature sensor, 70 electronic control unit for hybrid (hybrid ECU), 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 stroke sensor, 87 Vehicle speed sensor, 230 Counter rotor motor, 232 Inner rotor 234, outer rotor, MG1, MG2 motor.

Claims (10)

A power output device that outputs power to a drive shaft,
An internal combustion engine capable of outputting power to the drive shaft;
An electric motor capable of outputting power to the drive shaft;
Electric cranking means capable of executing cranking for starting the internal combustion engine;
Power storage means capable of exchanging power with the electric motor and the electric cranking means;
Based on the integrated value of the charging / discharging current of the power storage means, the deterioration factor indicating that the power storage means starts to deteriorate when a predetermined reference value is exceeded becomes a value that increases as discharge continues. Deterioration factor calculating means for calculating so as to be small when
Discharge allowable power setting means for setting discharge allowable power that is power allowed for discharging of the power storage means based on the temperature and remaining capacity of the power storage means;
When the calculated deterioration factor is equal to or greater than a predetermined limit start threshold smaller than the reference value, the discharge allowable power set by the discharge allowable power setting means so that the deterioration factor is equal to or less than the reference value. Discharge limiting means for limiting;
If the calculated deterioration factor is the discharge predetermined excess output requests made during startup of at least the internal combustion engine when the allowable power is not restricted is made by the discharge limiting means I said restriction start threshold below der The discharge allowable power set by the discharge allowable power setting means is temporarily increased, and the calculated deterioration factor becomes equal to or higher than the limit start threshold, and the discharge allowable power is limited by the discharge limit means. It is when the excess output request is made when that is the, the discharge allowable power increasing means for increasing the discharge allowable electric power that is limited by the limiting discharging means only at the start of the internal combustion engine temporarily,
Control means for controlling the internal combustion engine, the electric motor, and the electric cranking means so that the electric power discharged from the power storage means is within the range of the discharge allowable power;
A power output device comprising:   The power output device according to claim 1, wherein the discharge allowable power increasing means increases the discharge allowable power by a predetermined amount for a predetermined time when the discharge allowable power is temporarily increased.   The power output apparatus according to claim 1 or 2, wherein the excess output request is made when a required degree of driving force with respect to the drive shaft is a predetermined degree or more.   4. The power output apparatus according to claim 1, wherein the discharge limiting unit decreases the discharge allowable power as the deviation between the calculated deterioration factor and the limit start threshold increases. 5.   The power output apparatus according to any one of claims 1 to 4, wherein the deterioration factor is a value based on an integrated value of a current flowing through the power storage means. The electric cranking means is connected to the drive shaft and the engine shaft of the internal combustion engine and outputs at least a part of the power of the internal combustion engine to the drive shaft side with input and output of electric power and power. The power output device according to any one of claims 1 to 5, wherein the power output device is power power input / output means capable of exchanging power with the power storage means.   The electric power drive input / output means is connected to three axes of a generator motor capable of inputting / outputting power, the drive shaft, the engine shaft of the internal combustion engine, and a rotation shaft of the generator motor. The power output device according to claim 6, further comprising: a three-axis power input / output means for inputting / outputting power based on power input / output to / from any two of the shafts to / from the remaining shaft.   The power output apparatus according to any one of claims 1 to 7, wherein the power storage means is a lithium ion secondary battery.   A vehicle comprising: the power output device according to any one of claims 1 to 8; and a drive wheel coupled to the drive shaft. An internal combustion engine capable of outputting power to the drive shaft; an electric motor capable of outputting power to the drive shaft; an electric cranking means capable of executing cranking for starting the internal combustion engine; the electric motor and the electric crank; Power storage means capable of exchanging power with the ranking means, and discharge allowable power setting means for setting discharge allowable power that is power allowable for discharge of the power storage means based on the temperature and remaining capacity of the power storage means A method for controlling a power output device,
(A) Based on the integrated value of the charge / discharge current of the power storage means, the deterioration factor indicating that the deterioration of the power storage means starts when a predetermined reference value is exceeded becomes a larger value as discharge continues. Calculating to be small when charging with, and
(B) When the deterioration factor calculated in step (a) is equal to or greater than a predetermined limit start threshold value smaller than the reference value, the discharge allowable power setting means so that the deterioration factor is equal to or less than the reference value. Limiting the discharge allowable power set by
Made upon starting of at least said internal combustion engine when (c) the discharge allowable power is not restricted in step (a) the deterioration factor calculated in the step I the restriction start threshold below der (b) If the predetermined excess output request is made, with increasing discharge allowable power set by said discharge allowable power setting means temporarily, the calculated deterioration factor is equal to or greater than the restriction start threshold step ( If the excess output request is made when the discharge allowable power is limited in b), the discharge allowable power limited by the discharge limiting means is temporarily increased only when the internal combustion engine is started. Steps,
(D) controlling the internal combustion engine, the electric motor, and the electric cranking means so that electric power discharged from the electric storage means is within a range of the discharge allowable electric power;
A method for controlling a power output apparatus including:

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