JP6036546B2 - Hybrid car - Google Patents

Description

  The present invention relates to a hybrid vehicle, and more particularly, an engine, a first motor, a drive shaft coupled to an axle, an engine and a first motor, and a carrier and a sun gear coupled to a ring gear and a plurality of pinion gears. The present invention relates to a hybrid vehicle including a planetary gear, a second motor connected to a drive shaft, and a battery that exchanges electric power with the first motor and the second motor.

  Conventionally, this type of hybrid vehicle includes an engine, a first motor, a drive shaft coupled to an axle, an engine and a first motor, and a power in which a ring gear and a plurality of pinion gears are coupled to a sun gear. Engine upper / lower limit rotation based on upper / lower limit rotational speed on performance of first motor, including distribution / integration mechanism, second motor connected to drive shaft, and battery for exchanging electric power with first motor and second motor. Engine upper / lower limit rotational speed Nemax (pin), Nemin (pin) based on the number Nemax (mg1), Nemin (mg1) and the upper / lower limit rotational speed on the performance of the pinion gear of the power distribution and integration mechanism, and the upper / lower limit rotational speed on the engine performance Allowable minimum and minimum rotations taking into account the margins α and β determined in advance from the innermost rotation number among the number Nemax (eg) and the value 0 The numbers Nemax and Nemin are set, and the engine, the first motor, and the second motor are controlled so that the engine is operated at the rotation speed within the range of the set allowable maximum and minimum rotation speed and the required torque is output to the drive shaft. Have been proposed (see, for example, Patent Document 1). In this hybrid vehicle, such control not only suppresses over-rotation of the engine, but also suppresses over-rotation of the first motor and over-rotation of the pinion gear of the power distribution and integration mechanism.

JP 2008-247205 A

  In the hybrid vehicle described above, since the margins α and β are determined in advance, it is necessary to make the margins α and β large values to some extent, and there is a possibility that the operating range of the engine is limited more than necessary.

  The main purpose of the hybrid vehicle of the present invention is to set the operating range of the engine more appropriately.

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

The hybrid vehicle of the present invention
An engine, a first motor, a drive shaft coupled to an axle, a planetary gear in which a ring gear, a carrier coupled to a plurality of pinion gears and a sun gear are coupled to the engine and the first motor, and a planetary gear coupled to the drive shaft A hybrid vehicle comprising: a second motor; and a battery that exchanges power with the first motor and the second motor,
A value obtained by subtracting the first margin from the upper limit rotational speed derived from the pinion gear, which is the upper limit rotational speed of the engine obtained from the performance of the pinion gear, and a lower rotational speed derived from the pinion gear, which is the lower limit rotational speed of the engine, obtained from the performance of the pinion gear. And a value obtained by adding a second margin to the engine, a target rotational speed of the engine is set within a range, and the engine and the first motor are configured to travel while the engine is operated using the set target rotational speed. Control means for controlling the second motor;
The control means is means for setting at least one of the first margin and the second margin based on a maximum allowable power of the battery.
This is the gist.

  In the hybrid vehicle of the present invention, the value obtained by subtracting the first margin from the upper limit rotational speed derived from the pinion gear, which is the upper limit rotational speed of the engine obtained from the performance of the pinion gear, and the pinion gear, which is the lower rotational speed of the engine obtained from the performance of the pinion gear. A target engine speed is set within a range of the resulting lower limit engine speed plus the second margin, and the engine, the first motor, and the first motor are driven to run while the engine is operated using the set target engine speed. In the control of two motors, at least one of the first margin and the second margin is set based on the maximum allowable power of the battery. Thereby, the operating range of the engine can be set more appropriately.

  In such a hybrid vehicle of the present invention, the control means may be means for setting the first margin so that the absolute value of the maximum allowable input power of the battery becomes smaller as the absolute value of the battery becomes smaller. This is because when the engine speed increases following the increase in the target speed and overshoots the target speed, it is necessary to output torque in a direction to decrease the engine speed from the first motor. However, this is based on the reason that the smaller the absolute value of the maximum allowable input power of the battery is, the more the torque is limited and the degree of overshoot is likely to increase. Therefore, by setting the first margin so that the absolute value of the maximum allowable input power of the battery becomes smaller as the absolute value of the battery becomes smaller, the operating range of the engine can be increased when the absolute value of the maximum allowable input power of the battery is large. In addition, when the absolute value of the maximum allowable input power of the battery is small, the engine speed can be further suppressed from exceeding (exceeding) the pinion gear-derived upper limit speed.

  In the hybrid vehicle of the present invention, the control means may be means for setting the second margin so that the smaller the absolute value of the maximum allowable output power of the battery is, the larger the tendency is. This is because it is necessary to output torque from the first motor in the direction of increasing the engine speed when the engine speed decreases as the target speed decreases and undershoots the target speed. This is based on the reason that the smaller the absolute value of the maximum allowable output power of the battery is, the more the torque is limited and the degree of undershoot tends to increase. Therefore, by setting the second margin so that the absolute value of the maximum allowable output power of the battery becomes smaller, the engine operating range can be made larger when the absolute value of the maximum allowable output power of the battery is large. When the absolute value of the maximum allowable output power of the battery is small, the engine speed can be further suppressed from exceeding (below) the pinion gear-derived lower limit speed.

  In the hybrid vehicle of the present invention in which the second margin is set such that the absolute value of the maximum allowable output power of the battery increases as the absolute value decreases, the control means decreases as the absolute value of the maximum allowable output power of the battery decreases. The second margin may be a means for setting the second margin so as to increase and decrease as the absolute value of the maximum allowable input power of the battery decreases.

  In the hybrid vehicle of the present invention, the control means is an engine-derived upper limit rotational speed that is an upper limit rotational speed of the engine obtained from the performance of the engine and an upper limit rotational speed of the engine obtained from the performance of the first motor. The minimum value of the first motor-derived upper limit rotational speed and the value obtained by subtracting the first margin from the pinion gear-derived upper limit rotational speed, the value 0 as the lower limit rotational speed of the engine obtained from the engine performance, and the Within the range of the first motor-derived lower limit rotational speed, which is the lower limit rotational speed of the engine obtained from the performance of the first motor, and the maximum value of the value obtained by adding the second margin to the pinion gear-derived lower limit rotational speed It is also possible to control the engine so that the engine is operated at the number of revolutions.

1 is a configuration diagram showing an outline of a configuration of a hybrid vehicle 20 as an embodiment of the present invention. It is explanatory drawing which shows an example of the relationship between battery temperature Tb and basic input / output restrictions Wintmp, Wouttmp. It is explanatory drawing which shows an example of the relationship between the electrical storage ratio SOC of the battery 50, the output restriction correction coefficient kout, and the input restriction correction coefficient kin. It is a flowchart which shows an example of the drive control routine performed by HVECU70 of an Example. It is explanatory drawing which shows an example of the map for request | requirement torque setting. It is explanatory drawing which shows an example of the operating line of the engine 22, and a mode that the temporary rotation speed Nettmp and the temporary torque Tentmp are set. 4 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 planetary gear 30 when traveling while outputting power from the engine 22. FIG. It is explanatory drawing which shows an example of the upper limit side margin setting map. It is explanatory drawing which shows an example of the map for a lower limit side basic margin setting. It is explanatory drawing which shows an example of the map for a correction coefficient setting. It is explanatory drawing which shows an example of the relationship between the rotation speed Nr of the ring gear shaft 32a, and the allowable upper and lower limit rotation speeds Nemax and Nemin of the engine 22. It is explanatory drawing which shows an example of torque limitation Tm1min of motor MG1, and Tm1max. It is explanatory drawing which shows an example of the mode change of the target rotation speed Ne * of the engine 22, or the rotation speed Ne when it starts with the driving | operation of the engine 22, and the accelerator pedal 83 is largely depressed. An example of changes in time between the input / output power Pb of the battery 50 and the target rotational speed Ne * and the rotational speed Ne of the engine 22 when the accelerator pedal 83 is stepped back while traveling at a high vehicle speed is shown. It is explanatory drawing.

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

  FIG. 1 is a configuration diagram showing an outline of the configuration of a hybrid vehicle 20 as an embodiment of the present invention. As shown in the drawing, the hybrid vehicle 20 of the embodiment includes an engine 22 that outputs power using gasoline or light oil as a fuel, an engine electronic control unit (hereinafter referred to as an engine ECU) 24 that controls the drive of the engine 22, an engine, and the like. A carrier 34 is connected to a crankshaft 26 as an output shaft 22 via a damper 28 and a plurality of pinion gears 33 is connected to the crankshaft 26, and is connected to drive wheels 63a and 63b via a differential gear 62 and a gear mechanism 60. A planetary gear 30 in which a ring gear 32 is connected to a ring gear shaft 32a as a shaft, a motor MG1 configured as, for example, a known synchronous generator motor and having a rotor connected to the sun gear 31 of the planetary gear 30, and a known synchronous generator motor, for example. Constructed as ring shaft as drive shaft The motor MG1, MG2 is controlled by controlling a motor MG2 having a rotor connected to the shaft 32a via a reduction gear 35, inverters 41, 42 for driving the motors MG1, MG2, and switching elements of the inverters 41, 42. A motor electronic control unit (hereinafter referred to as a motor ECU) 40 that controls the driving of the motor, a battery 50 that is configured as, for example, a lithium ion secondary battery and exchanges power with the motors MG1 and MG2 via the inverters 41 and 42, and a battery 50, a battery electronic control unit (hereinafter referred to as a battery ECU) 52 for managing 50 and a hybrid electronic control unit (hereinafter referred to as an HVECU) 70 for controlling the entire vehicle.

  Although not shown, the engine ECU 24 is configured as a microprocessor centered on a CPU, and includes a ROM for storing a processing program, a RAM for temporarily storing data, an input / output port, and a communication port in addition to the CPU. . The engine ECU 24 receives signals from various sensors that detect the operating state of the engine 22, for example, a crank position θcr from a crank position sensor that detects the rotational position of the crankshaft 26, and the like. From the ECU 24, various control signals for driving the engine 22, for example, a drive signal to the fuel injection valve, a drive signal to the throttle motor that adjusts the position of the throttle valve, and an ignition coil integrated with the igniter are supplied. A control signal, a control signal to a variable valve timing mechanism capable of changing the opening / closing timing of the intake valve, and the like are output via an output port. The engine ECU 24 is in communication with the HVECU 70, controls the operation of the engine 22 by a control signal from the HVECU 70, and outputs data related to the operation state of the engine 22 to the HVECU 70 as necessary. The engine ECU 24 also calculates the rotational speed of the crankshaft 26, that is, the rotational speed Ne of the engine 22 based on a signal from a crank position sensor (not shown) attached to the crankshaft 26.

  Although not shown, the motor ECU 40 is configured as a microprocessor centered on a CPU, and includes a ROM for storing a processing program, a RAM for temporarily storing data, an input / output port, and a communication port in addition to the CPU. . The motor ECU 40 receives signals necessary for driving and controlling the motors MG1 and MG2, for example, rotational positions θm1 and θm2 from rotational position detection sensors 43 and 44 that detect the rotational positions of the rotors of the motors MG1 and MG2, and not shown. A phase current applied to the motors MG1 and MG2 detected by the current sensor is input via the input port, and the motor ECU 40 outputs a switching control signal to switching elements (not shown) of the inverters 41 and 42. It is output through the port. The motor ECU 40 is in communication with the HVECU 70, controls the driving of the motors MG1 and MG2 by a control signal from the HVECU 70, and outputs data related to the operating state of the motors MG1 and MG2 to the HVECU 70 as necessary. The motor ECU 40 also calculates the rotational angular velocities ωm1, ωm2 and the rotational speeds Nm1, Nm2 of the motors MG1, MG2 based on the rotational positions θm1, θm2 of the rotors of the motors MG1, MG2 from the rotational position detection sensors 43, 44. ing.

  Although not shown, the battery ECU 52 is configured as a microprocessor centered on a CPU, and includes a ROM for storing a processing program, a RAM for temporarily storing data, an input / output port, and a communication port in addition to the CPU. . The battery ECU 52 is attached to a signal necessary for managing the battery 50, for example, an inter-terminal voltage Vb from a voltage sensor installed between the terminals of the battery 50 or an electric power line connected to the output terminal of the battery 50. The charge / discharge current Ib from the current sensor, the battery temperature Tb from the temperature sensor 51 attached to the battery 50, and the like are input, and data on the state of the battery 50 is transmitted to the HVECU 70 by communication as necessary. Further, in order to manage the battery 50, the battery ECU 52 is a power storage that is a ratio of the capacity of the electric power that can be discharged from the battery 50 at that time based on the integrated value of the charge / discharge current Ib detected by the current sensor. The ratio SOC is calculated, and the input / output limits Win and Wout, which are the maximum allowable input / output power that may charge / discharge the battery 50, are calculated based on the calculated storage ratio SOC and the battery temperature Tb. The input / output limits Win, Wout of the battery 50 are set as basic input / output limits Wintmp, Wouttmp as basic values of the input / output limits Win, Wout based on the battery temperature Tb, and based on the storage rate SOC of the battery 50. The output restriction correction coefficient kout and the input restriction correction coefficient kin are set, and the set basic input / output restriction Wintmp and Wouttmp are multiplied by the input restriction correction coefficient kin and the output restriction correction coefficient kout. it can. FIG. 2 shows an example of the relationship between the battery temperature Tb and the basic input / output limits Wintmp, Wouttmp, and FIG. 3 shows an example of the relationship between the storage ratio SOC of the battery 50, the output limiting correction coefficient kout, and the input limiting correction coefficient kin. Indicates.

  The HVECU 70 is configured as a microprocessor centered on the CPU 72, and includes a ROM 74 that stores a processing program, a RAM 76 that temporarily stores data, an input / output port, and a communication port in addition to the CPU 72. The HVECU 70 includes an ignition signal from the ignition switch 80, a shift position SP from the shift position sensor 82 that detects the operation position of the shift lever 81, and an accelerator opening degree from the accelerator pedal position sensor 84 that detects the amount of depression of the accelerator pedal 83. Acc, the brake pedal position BP from the brake pedal position sensor 86 that detects the depression amount of the brake pedal 85, the vehicle speed V from the vehicle speed sensor 88, and the like are input via the input port. As described above, the HVECU 70 is connected to the engine ECU 24, the motor ECU 40, and the battery ECU 52 via the communication port, and exchanges various control signals and data with the engine ECU 24, the motor ECU 40, and the battery ECU 52.

  In the hybrid vehicle 20 of the embodiment thus configured, the required torque Tr * 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 by the driver. The engine 22, the motor MG1, and the motor MG2 are controlled to be calculated so that the required power corresponding to the required torque Tr * is output to the ring gear shaft 32a. As the operation control of the engine 22, the motor MG1, and the motor MG2, the operation of the engine 22 is controlled so that the power corresponding to the required power is output from the engine 22, and all the power output from the engine 22 is transmitted to the planetary gear 30 and the motor. Torque conversion is performed by the motor MG1 and the motor MG2, and the torque conversion operation mode for driving and controlling the motor MG1 and the motor MG2 to be output to the ring gear shaft 32a, and the sum of the required power and the power required for charging and discharging the battery 50 are met. Operation of the engine 22 is controlled so that power is output from the engine 22, and all or part of the power output from the engine 22 with charge / discharge of the battery 50 is torque generated by the planetary gear 30, the motor MG1, and the motor MG2. With the conversion, the required power becomes the ring gear shaft 32. Charge / discharge operation mode for driving and controlling the motor MG1 and the motor MG2 so as to be output to the motor, and a motor operation mode for controlling the operation so as to output the power corresponding to the required power from the motor MG2 to the ring gear shaft 32a by stopping the operation of the engine 22. and so on.

  Next, the operation of the thus configured hybrid vehicle 20 of the embodiment will be described. FIG. 4 is a flowchart illustrating an example of a drive control routine executed by the HVECU 70 of the embodiment. This routine is repeatedly executed every predetermined time (for example, every several msec).

  When the drive control routine is executed, first, the CPU 72 of the HVECU 70 first determines the accelerator opening Acc from the accelerator pedal position sensor 84, the vehicle speed V from the vehicle speed sensor 88, the rotational speeds Nm1, Nm2 of the motors MG1, MG2, and the battery 50. Data necessary for control such as input / output restrictions Win and Wout are input (step S100). Here, the rotational speeds Nm1, Nm2 of the motors MG1, MG2 are calculated from the motor ECU 40 based on the rotational positions θm1, θm2 of the rotors of the motors MG1, MG2 detected by the rotational position detection sensors 43, 44. The input was made by communication. Further, the input / output limits Win and Wout of the battery 50 are set based on the battery temperature Tb of the battery 50 and the storage ratio SOC of the battery 50 and are input from the battery ECU 52 by communication.

  When the data is input in this way, the required torque Tr * required for traveling (to be output to the ring gear shaft 32a as the drive shaft) is set based on the input accelerator opening Acc and the vehicle speed V, and the set required torque Tr is set. The travel power Pdrv * required for travel is calculated by multiplying * by the rotational speed Nr of the ring gear shaft 32a, and the required charge / discharge power Pb * (battery based on the storage ratio SOC of the battery 50 is calculated from the calculated travel power Pdrv *. The required power Pe * required for the vehicle (to be output from the engine 22) is calculated by subtracting the positive value when discharging from 50 (step S110). Here, in the embodiment, the required torque Tr * is stored in the ROM 74 as a required torque setting map by predetermining the relationship among the accelerator opening Acc, the vehicle speed V, and the required torque Tr *. When the vehicle speed V is given, the corresponding required torque Tr * is derived and set from the stored map. An example of the required torque setting map is shown in FIG. Further, the rotation speed Nr of the ring gear shaft 32a can be calculated by dividing the rotation speed Nm2 of the motor MG2 by the gear ratio Gr of the reduction gear 35, or can be calculated by multiplying the vehicle speed V by a conversion factor.

  Subsequently, based on the required power Pe * and an operation line for efficiently operating the engine 22 (for example, an optimum fuel efficiency operation line), the target rotational speed Ne * and the target torque Te * of the engine 22 are assumed as temporary values. A temporary rotational speed Nettmp and a temporary torque Tentmp are set (step S120). FIG. 6 shows an example of the operation line of the engine 22 and how the temporary rotation speed Nettmp and the temporary torque Tentmp are set. As shown in the figure, the temporary rotational speed Nettmp and the temporary torque Tentmp can be obtained as an intersection of the operation line and a curve having a constant required power Pe * (equal power line of the required power Pe *).

  Next, the upper and lower limit rotation speeds Nm1max and Nm1min in the performance of the motor MG1, the rotation speed Nr (= Nm2 / Gr) of the ring gear shaft 32a, and the gear ratio ρ (the number of teeth of the sun gear / the number of teeth of the ring gear) of the planetary gear 30 are determined. Using the following equations (1) and (2), the upper and lower limit rotational speeds Nemax (mg1) and Nemin (mg1) of the engine 22 are calculated (step S130). Here, the upper and lower limit rotational speeds Nm1max and Nm1min in the performance of the motor MG1 are the upper limit rotational speed as the positive rotation side and the lower limit rotational speed as the negative rotation side in the rated value of the motor MG1. Expressions (1) and (2) are dynamic relational expressions for the rotating element of the planetary gear 30. FIG. 7 is an explanatory diagram showing an example of a collinear diagram showing a dynamic relationship between the rotational speed and torque in the rotating element of the planetary gear 30 when traveling while outputting power from the engine 22. 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 of the ring gear 32 (ring gear shaft 32a) obtained by dividing the number Nm2 by the gear ratio Gr of the reduction gear 35 is shown. The two thick arrows on the R-axis act on the ring gear shaft 32a output from the motor MG2 and applied to the ring gear shaft 32a via the planetary gear 30, and output from the motor MG2 and applied to the ring gear shaft 32a. Torque. Expressions (1) and (2) can be easily derived from this alignment chart by using the upper and lower limit rotation speeds Nm1max and Nm1min as the rotation speed Nm1 of the motor MG1.

Nemax (mg1) = ρ ・ Nm1max / (1 + ρ) + Nm2 / (Gr ・ (1 + ρ)) (1)
Nemin (mg1) = ρ ・ Nm1min / (1 + ρ) + Nm2 / (Gr ・ (1 + ρ)) (2)

  Subsequently, the upper and lower limit rotation speeds Npinmax, Npinmin and the rotation speed Nr (= Nm2 / Gr) of the ring gear shaft 32a and the gear ratio γ of the planetary gear 30 with respect to the pinion gear 33 (number of teeth of the pinion gear / ring gear) The upper and lower limit rotational speeds Nemax (pin) and Nemin (pin) of the engine 22 are calculated by the following formulas (3) and (4) using the number of teeth of (step S140). Here, the upper and lower limit rotational speeds Npinmax and Npinmin on the performance of the pinion gear 33 are the upper limit rotational speed as the positive rotation side and the lower limit rotational speed as the negative rotation side in the structural rated value of the planetary gear 30.

Nemax (pin) = Nm2 / Gr + γ ・ Npinmax (3)
Nemin (pin) = Nm2 / Gr + γ ・ Npinmin (4)

  Then, based on the input / output limits Win and Wout of the battery 50, margins α and β for the upper and lower limit rotational speeds Nemax (pin) and Nemin (pin) of the engine 22 are set (step S150).

  Here, in the embodiment, the margin α is determined in advance by storing the relationship between the input limit Win of the battery 50 and the margin α in a ROM (not shown) as an upper limit side margin setting map. When given, the corresponding margin α is derived from the stored map and set. An example of the upper limit side margin setting map is shown in FIG. As shown in the figure, the margin α is set so as to increase as the absolute value of the input limit Win of the battery 50 decreases. The reason for setting the margin α for such a tendency will be described later.

  In the embodiment, the margin β is calculated by multiplying the basic margin βtmp as the basic value of the margin β based on the output limit Wout of the battery 50 by the correction coefficient km based on the input limit Win of the battery 50. . In the embodiment, the basic margin βtmp is determined in advance by storing the relationship between the output limit Wout of the battery 50 and the margin β in a ROM (not shown) as a lower limit side basic margin setting map, and the output limit Wout of the battery 50 is given. The corresponding margin β is derived from the stored map and set. An example of the lower limit side basic margin setting map is shown in FIG. As shown in the figure, the basic margin βtmp is set such that the battery 50 tends to increase as the absolute value of the output limit Wout decreases. In the embodiment, the correction coefficient km is a map in which the relationship between the input limit Win of the battery 50 and the correction coefficient km is determined in advance and stored in a ROM (not shown), and the input limit Win of the battery 50 is given. Are set by multiplying the corresponding correction coefficient km. An example of the correction coefficient setting map is shown in FIG. As shown in the figure, the correction coefficient km is set so as to decrease as the absolute value of the input limit Win of the battery 50 decreases. Accordingly, the margin β is set so as to increase as the absolute value of the output limit Wout of the battery 50 decreases, and to decrease as the absolute value of the input limit Win of the battery 50 decreases. The reason for setting the margin β in such a tendency will be described later.

  When the upper and lower limit rotational speeds Nemax (mg1) and Nemmin (mg1) of the engine 22 and the upper and lower limit rotational speeds Nemax (pin) and Nemin (pin) of the engine 22 and the margins α and β are set in this way, the following equation (5) is obtained. As described above, the value obtained by subtracting the margin α from the upper limit rotational speed Nemax (mg1) of the engine 22 and the upper limit rotational speed Nemax (pin) of the engine 22 and the upper limit rotational speed Nemax in the performance of the engine 22 The minimum value of (eg) is set to the allowable upper limit rotational speed Nemax of the engine 22, and the lower limit rotational speed Nemin (mg1) of the engine 22 and the lower limit rotational speed Nemin (pin) of the engine 22 as shown in Expression (6). ) Plus a margin β (Nemin (pin) + β) and a value as a lower limit rotational speed in the performance of the engine 22 Tonouchi set the maximum value to the allowable lower limit rotation speed Nemin of the engine 22 (step S160). Here, the upper limit rotational speed Nemax (eg) in the performance of the engine 22 is an upper limit rotational speed as a rated value of the engine 22. FIG. 11 shows an example of the relationship between the rotation speed Nr of the ring gear shaft 32a and the allowable upper and lower limit rotation speeds Nemax and Nemin of the engine 22. In the example of FIG. 11, the allowable upper limit rotational speed Nemax of the engine 22 is less than the rotational speed Nr1 of the intersection of the upper limit rotational speed Nemax (mg1) and the value (Nemax (pin) −α). A value (Nemax (pin) −α) is set in the region, and an upper limit rotational speed Nemax (mg1) is set in a region where the rotational speed Nr of the ring gear shaft 32a is equal to or higher than the rotational speed Nr1. Further, the allowable lower limit rotational speed Nemin of the engine 22 is set to a value of 0 in a region where the rotational speed Nr of the ring gear shaft 32a is less than the rotational speed Nr2 at the intersection of the lower limit rotational speed Nemin (mg1) and the value 0, and the ring gear shaft 32a. In the region where the rotational speed Nr is equal to or higher than the rotational speed Nr2 and is lower than the rotational speed Nr3 at the intersection of the lower limit rotational speed Nemin (mg1) and the value (Nemin (pin) + β), the lower limit rotational speed Nemin (mg1) is set. A value (Nemin (pin) + β) is set in a region where the rotational speed Nr of 32a is equal to or higher than the rotational speed Nr3.

Nemax = min (Nemax (mg1), Nemax (pin) -α, Nemax (eg)) (5)
Nemin = min (Nemin (mg1), Nemin (pin) + β, 0) (6)

  When the allowable upper limit rotational speed Nemax and the allowable lower limit rotational speed Nemin of the engine 22 are set in this way, the temporary rotational speed Netmp of the engine 22 is set to the allowable upper limit rotational speed Nemax and the allowable lower limit rotational speed Nemin as shown in the following equation (7). The target rotational speed Ne * of the engine 22 is set in a limited manner, and the target torque Te * of the engine 22 is set by dividing the required power Pe * by the set target rotational speed Ne * (step S170). By this process, when the temporary rotational speed Netmp falls within the range between the allowable upper limit rotational speed Nemax and the allowable lower limit rotational speed Nemin, the temporary rotational speed Netmp is set to the target rotational speed Ne *, and the temporary rotational speed Netmp is set to the allowable upper limit rotational speed. When it is larger than the number Nemax, the allowable upper limit rotational speed Nemax is set to the target rotational speed Ne *, and when the temporary rotational speed Netmp is smaller than the allowable lower limit rotational speed Nemin, the allowable lower limit rotational speed Nemin is set to the target rotational speed Ne *. become.

  Ne * = max (min (Netmp, Nemax), Nemin) (7)

  Next, using the target rotational speed Ne * of the engine 22, the rotational speed Nr (= Nm2 / Gr) of the ring gear shaft 32a, and the gear ratio ρ of the planetary gear 30, the target rotational speed Nm1 * of the motor MG1 according to the following equation (8): And the calculated target rotational speed Nm1 * of the motor MG1, the input rotational speed Nm1 of the motor MG1, the target torque Te * of the engine 22, and the gear ratio ρ of the planetary gear 30 according to the equation (9). A temporary torque Tm1tmp as a temporary value of the torque command Tm1 * is calculated (step S180). Here, Expression (8) is a dynamic relational expression for the rotating element of the planetary gear 30, and can be easily derived by using the alignment chart of FIG. Expression (9) is a relational expression in feedback control for rotating the motor MG1 at the target rotation speed Nm1 * (rotating the engine 22 at the target rotation speed Ne *). The second term “k1” is the gain of the proportional term, and the third term “k2” of the right side is the gain of the integral term.

Nm1 * = Ne * ・ (1 + ρ) / ρ-Nm2 / (Gr ・ ρ) (8)
Tm1tmp = -ρ ・ Te * / (1 + ρ) + k1 (Nm1 * -Nm1) + k2∫ (Nm1 * -Nm1) dt (9)

  Subsequently, as shown in the following equation (10), the torque command Tm1 * of the motor MG1 divided by the gear ratio ρ of the planetary gear 30 is added to the required torque Tr * and further divided by the gear ratio Gr of the reduction gear 35. Then, a temporary torque Tm2tmp as a temporary value of the torque command Tm2 * of the motor MG2 is calculated (step S190). Here, equation (10) can be easily derived by using the alignment chart of FIG.

  Tm2tmp = (Tr * + Tm1 * / ρ) / Gr (10)

  Then, torque limits Tm1min and Tm1max are set as upper and lower limits of the torque that may be output from the motor MG1 that satisfies both the following expressions (11) and (12) (step S200). Here, Expression (11) is a relationship in which the total torque output from the motor MG1 and the motor MG2 to the ring gear shaft 32a is within a range from the value 0 to the required torque Tr *. This is a relationship in which the sum of the electric power input / output by the motor MG1 and the motor MG2 is within the range of the input / output limits Win, Wout of the battery 50. FIG. 12 is an explanatory diagram showing an example of torque limits Tm1min and Tm1max of the motor MG1. The torque limits Tm1min and Tm1max can be obtained as the maximum value and the minimum value of the temporary torque Tm1tmp in the region indicated by the oblique lines in the figure. As can be seen from FIG. 12, when the required torque Tr * is a positive value, the relationship that the sum of the torques output from the motor MG1 and the motor MG2 to the ring gear shaft 32a becomes the required torque Tr *, and the motor MG1 and the motor MG2 The driving point of the motor MG1 that satisfies the relationship that the sum of the electric power input and output by the battery 50 becomes the input limit Win of the battery 50 is set to the torque limit Tm1min, that is, the expression (13) obtained from the expressions (11) and (12) ) To calculate the torque limit Tm1min, and the relationship in which the sum of torques output from the motor MG1 and the motor MG2 to the ring gear shaft 32a is 0 and the sum of electric power input and output by the motor MG1 and the motor MG2 is the battery. The driving point of the motor MG1 that satisfies the relationship of 50 output limits Wout is the torque limit Tm1ma. Will calculate the torque limit Tm1max by immediate Chi equation set (11) and (12) because the resulting formula (14).

0 ≦ -Tm1tmp / ρ + Tm2tmp ・ Gr ≦ Tr * (11)
Win ≦ Tm1tmp ・ Nm1 + Tm2tmp ・ Nm2 ≦ Wout (12)
Tm1min = (Win ・ Gr-Tr * ・ Nm2) / (Nm1 ・ Gr + Nm2 / ρ) (13)
Tm1max = Wout ・ Gr / (Nm1 ・ Gr + Nm2 / ρ) (14)

  When the torque limits Tm1min and Tm1max are set in this way, as shown in the following equation (15), the temporary torque Tm1tmp of the motor MG1 is limited by the torque limits Tm1min and Tm1max, and the torque command Tm1 * of the motor MG1 is set (step S210). .

  Tm1 * = max (min (Tm1tmp, Tm1max), Tm1min) (15)

  Then, as shown in the following equations (16) and (17), the motor MG1 obtained by multiplying the input / output limits Win, Wout of the battery 50 and the torque command Tm1 * of the motor MG1 by the current rotational speed Nm1 of the motor MG1. Is divided by the rotational speed Nm2 of the motor MG2 to calculate torque limits Tm2min and Tm2max as upper and lower limits of torque that may be output from the motor MG2 (step S220). As shown in (18), the torque command Tm2 * of the motor MG2 is set by limiting the temporary torque Tm2tmp of the motor MG2 with the torque limits Tm2min and Tm2max (step S230).

Tm2min = (Win-Tm1 * ・ Nm1) / Nm2 (16)
Tm2max = (Wout-Tm1 * ・ Nm1) / Nm2 (17)
Tm2 * = max (min (Tm2tmp, Tm2max), Tm2min) (18)

  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 set in this way, the target rotational speed Ne * and target torque Te * of the engine 22 are set in the engine ECU 24. The torque commands Tm1 * and Tm2 * for the motors MG1 and MG2 are transmitted to the motor ECU 40 (step S380), and this routine ends. The engine ECU 24 that has received the target engine speed Ne * and the target torque Te * of the engine 22 takes in the intake air amount of the engine 22 so that the engine 22 is operated at an operating point consisting of the target engine speed Ne * and the target torque Te *. Control, fuel injection control, ignition control, etc. are performed. The motor ECU 40 that receives the torque commands Tm1 * and Tm2 * of the motors MG1 and MG2 performs switching control of the switching elements of the inverters 41 and 42 so that the motors MG1 and MG2 are driven by the torque commands Tm1 * and Tm2 *. .

  Here, as described above, the margin α is set so as to increase as the absolute value of the input limit Win of the battery 50 decreases, and tends to increase as the absolute value of the output limit Wout of the battery 50 decreases. The reason why the margin β is set so as to decrease as the absolute value of the input limit Win decreases. First, the margin α will be described, and then the margin β will be described.

  In order to explain the margin α, consider a case where the vehicle starts with the operation of the engine 22 and the accelerator pedal 83 is greatly depressed. FIG. 13 is an explanatory diagram showing an example of how the target rotational speed Ne * and the rotational speed Ne of the engine 22 change over time at this time. As the accelerator pedal 83 is depressed greatly, the temporary rotational speed Netmp of the engine 22 based on the required power Pe * increases, and as shown in the figure, the target rotational speed Ne * of the engine 22 becomes the allowable upper limit rotational speed Nemax (= Nemax (pin ) −α) When the rotation speed increases within the following range, the rotational speed Ne of the engine 22 increases following the target rotational speed Ne *, but may overshoot the target rotational speed Ne *. When the rotational speed Ne of the engine 22 is greater than the target rotational speed Ne *, the motor MG1 is in a negative direction (the direction in which the rotational speed Ne of the engine 22 is decreased) in order to set the rotational speed Ne to the target rotational speed Ne *. The torque limit Tm1min increases (the absolute value decreases) as the input limit Win of the battery 50 increases (the absolute value decreases), as can be understood from the above equation (13). From the above, it is considered that the greater the input limit Win, the greater the degree of overshoot of the rotation speed Ne with respect to the target rotation speed Ne *. Based on this, in the embodiment, the margin α is set such that the smaller the absolute value of the input limit Win of the battery 50 is, the larger the margin α is. Thus, when the absolute value of the input limit Win is large, the operating range of the engine 22 can be increased by decreasing the margin α, and when the absolute value of the input limit Win is small, the margin α is increased. Thus, it is possible to more sufficiently suppress the rotation speed Ne of the engine 22 from exceeding the upper limit rotation speed Nemax (pin) (the rotation speed of the pinion gear 33 of the planetary gear 30 exceeds the upper limit rotation speed Npinmax).

  In order to explain the margin β, consider the case where the accelerator pedal 83 is depressed while traveling at a high vehicle speed. FIG. 14 is an explanatory diagram showing an example of a temporal change in the input / output power Pb of the battery 50 and the target rotational speed Ne * and the rotational speed Ne of the engine 22 at this time. As the accelerator pedal 83 is stepped back, the temporary rotational speed Netmp of the engine 22 based on the required power Pe * decreases, and as shown in the figure, the target rotational speed Ne * of the engine 22 becomes the allowable lower limit rotational speed Nemin (= Nemax (pin ) + Β) When the rotation speed decreases within the above range, the rotational speed Ne of the engine 22 decreases following the target rotational speed Ne *, but may undershoot relative to the target rotational speed Ne *. First, when the rotational speed Ne of the engine 22 is decreased, torque in the negative direction is output from the motor MG1, but the input limit Win of the battery 50 is large (absolute value) as can be seen from the above equation (13). As the input limit Win increases, the motor MG1 gradually decreases the rotational speed Ne of the engine 22, and the rotational speed Ne becomes the target rotational speed. It is thought that the degree becomes small when undershooting for several Ne *. When the rotational speed Ne of the engine 22 is smaller than the target rotational speed Ne *, the motor MG1 is increased in the positive direction (the rotational speed Ne of the engine 22 is increased) so that the rotational speed Ne becomes the target rotational speed Ne *. Direction), the torque limit Tm1max decreases as the output limit Wout of the battery 50 decreases, so that the rotation speed Ne decreases as the output limit Wout decreases. It is considered that the degree of undershoot with respect to the target rotational speed Ne * tends to increase. Based on this, in the embodiment, the margin β is set so that the absolute value of the output limit Wout of the battery 50 tends to increase as the absolute value of the output limit Wout decreases and the absolute value of the input limit Win of the battery 50 decreases. . Thus, when the absolute value of the input limit Win is small and the absolute value of the output limit Wout is large, the operating range of the engine 22 can be increased by reducing the margin β, and the absolute value of the input limit Win is increased. When the absolute value of the output limit Wout is small, the rotational speed Ne of the engine 22 exceeds the lower limit rotational speed Nemax (pin) by increasing the margin β (the rotational speed of the pinion gear 33 of the planetary gear 30 is less than the lower rotational speed Npinmin). (Exceeding) can be more sufficiently suppressed. In the embodiment, the basic margin βtmp and the correction coefficient km are set so that the degree of change in the margin β with respect to the change in the output limit Wout is higher than the degree of change in the margin β with respect to the change in the input limit Win. This is based on the reason that the degree of undershoot of the rotation speed Ne with respect to the target rotation speed Ne * is more influenced by the output limit Wout than the influence of the input limit Win by experiments and analysis. .

  In the hybrid vehicle 20 of the embodiment described above, based on the upper limit rotational speed Nemax (mg1) of the engine 22 based on the upper limit rotational speed Nm1max on the performance of the motor MG1, and on the upper limit rotational speed Npinmax on the performance of the pinion gear 33 of the planetary gear 30. A value (Nemax (pin) −α) obtained by subtracting the margin α based on the output limit Wout of the battery 50 from the upper limit rotational speed Nemax (pin) of the engine 22, an upper limit rotational speed Nemax (eg) on the performance of the engine 22, Is set to the allowable upper limit rotational speed Nemax of the engine 22. Further, the lower limit rotational speed Nemin (mg1) of the engine 22 based on the lower limit rotational speed Nm1min in terms of the performance of the motor MG1 and the lower limit rotational speed Nemin (pin) of the engine 22 based on the lower limit rotational speed Npinmin in terms of the performance of the pinion gear 33 of the planetary gear 30. ) And a margin β based on the input / output limits Win and Wout of the battery 50 (Nemin (pin) + β), and the value 0 as the lower limit rotational speed on the performance of the engine 22, the maximum value is determined as the engine 22. Is set to the allowable lower limit rotation speed Nemin. Then, the engine 22 is controlled by setting the target engine speed Ne * of the engine 22 within the set allowable upper and lower engine speeds Nemax and Nemin. Thereby, the operating range of the engine 22 can be set more appropriately according to the input / output limits Win and Wout of the battery 50.

  In the hybrid vehicle 20 of the embodiment, the margin β is set based on the input / output limits Win and Wout of the battery 50, but based only on the output limit Wout of the battery 50 (without considering the input limit Win). ) It may be set.

  In the hybrid vehicle 20 of the embodiment, the margin α is set based on the input limit Win of the battery 50 and the margin β is set based on the input / output limits Win, Wout of the battery 50. The margin β is set based on a predetermined value, and a predetermined value may be used for the margin β, and the margin β is based on the input / output limits Win and Wout (or only the output limit Wout) of the battery 50. However, for the margin α, a predetermined value may be used.

  In the hybrid vehicle 20 of the embodiment, the upper limit rotational speed Nemax (mg1) of the engine 22 based on the upper limit rotational speed Nm1max on the performance of the motor MG1 and the upper limit rotational speed Npinmax on the performance of the pinion gear 33 of the planetary gear 30 are determined. The minimum value of the value obtained by subtracting the margin α based on the input limit Win of the battery 50 from the upper limit rotation speed Nemax (pin) (Nemax (pin) −α) and the upper limit rotation speed Nemax (eg) on the performance of the engine 22 Is set to the allowable upper limit rotational speed Nemax of the engine 22, but when the engine 22 or the motor MG1 having a large rated value is used, specifically, the upper limit rotational speed is set regardless of the vehicle speed V (the rotational speed Nm2 of the motor MG2). The number Nemax (mg1) and the upper limit rotational speed Nemax (eg) are the upper limit rotational speed Nema. When it is larger than x (pin), the value (Nemax (pin) −α) is set to the allowable upper limit speed Nemax of the engine 22 regardless of the vehicle speed V. Therefore, the upper limit speed Nemax (mg1) and the upper limit The rotation speed Nemax (eg) may not be taken into consideration. Similarly, when the lower limit rotational speed Nemin (mg1) is smaller than the lower limit rotational speed Nemin (pin) regardless of the vehicle speed V, the value (Nemin (pin) + β) is within a range of 0 or more regardless of the vehicle speed V. Since the allowable lower limit rotational speed Nemin of the engine 22 is set, the lower limit rotational speed Nemin (mg1) may not be considered.

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

  The correspondence between the main elements of the embodiment 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 the “engine”, the motor MG1 corresponds to the “first motor”, the planetary gear 30 corresponds to the “planetary gear”, the motor MG2 corresponds to the “second motor”, and the battery 50 Corresponds to the “battery”, the HVECU 70 that executes the drive control routine of FIG. 4, the engine ECU 24 that controls the engine 22 based on the target rotational speed Ne * and the target torque Te * from the HVECU 70, and the torque command from the HVECU 70 The motor ECU 40 that controls the motors MG1 and MG2 based on Tm1 * and Tm2 * corresponds to “control means”.

  Here, the “engine” is not limited to the engine 22 that outputs power using gasoline or light oil as a fuel, and may be any type of engine. The “first motor” is not limited to the motor MG1 configured as a synchronous generator motor, and may be any type of motor such as an induction motor. The “planetary gear” is not limited to the planetary gear 30, but is composed of a combination of a plurality of planetary gears, etc. A ring gear and a plurality of pinion gears are coupled to a drive shaft coupled to an axle, an engine, and a first motor. Any carrier can be used as long as the carrier and the sun gear are connected. The “second motor” is not limited to the motor MG2 configured as a synchronous generator motor, and may be any type of motor as long as it is connected to the drive shaft, such as an induction motor. The “battery” is not limited to the battery 50 configured as a lithium ion secondary battery, and the first motor, the second motor, and the electric power such as a nickel hydride secondary battery, a nickel cadmium secondary battery, and a lead storage battery. Any type of battery may be used as long as it exchanges information. The “control unit” is not limited to a combination of the HVECU 70, the engine ECU 24, and the motor ECU 40, and may be a single electronic control unit. Further, as the “control means”, the engine 22 based on the upper limit rotational speed Nemax (mg1) of the engine 22 based on the upper limit rotational speed Nm1max on the performance of the motor MG1 and the upper limit rotational speed Npinmax on the performance of the pinion gear 33 of the planetary gear 30. The minimum value of the value obtained by subtracting the margin α based on the output limit Wout of the battery 50 (Nemax (pin) −α) from the upper limit rotational speed Nemax (pin) of the engine 22 and the upper limit rotational speed Nemax (eg) on the performance of the engine 22 The value is set to the allowable upper limit rotation speed Nemax of the engine 22, and the lower limit rotation speed Nemin (mg1) of the engine 22 based on the lower limit rotation speed Nm1min on the performance of the motor MG1 and the lower limit rotation speed on the performance of the pinion gear 33 of the planetary gear 30 Lower limit speed Nemin of engine 22 based on Npinmin The maximum value of (pin) plus a margin β based on the input / output limits Win and Wout of the battery 50 (Nemin (pin) + β) and a value 0 as the lower limit rotational speed on the performance of the engine 22 is the maximum value. The allowable lower limit rotational speed Nemin of the engine 22 is set, and the target rotational speed Ne * of the engine 22 is set within the range of the set allowable upper and lower rotational speeds Nemax and Nemin, and the engine 22 is operated at the target rotational speed Ne *. The engine 22 and the motors MG1, MG2 are not limited to controlling the motor 22 and the motor MG1, but the value obtained by subtracting the first margin from the pinion gear-derived upper limit speed, which is the upper limit speed of the engine obtained from the performance of the pinion gear. In addition, a second margin is added to the lower limit speed due to the pinion gear, which is the lower limit speed of the engine obtained from the performance of the pinion gear. A target rotational speed of the engine is set within the range of the obtained value, and the engine, the first motor, and the second motor are controlled to run while the engine is operated using the set target rotational speed, and the first margin As long as at least one of the second margin and the second margin is set on the basis of the maximum allowable power of the battery, any one may be used.

  The correspondence between the main elements of the embodiment and the main elements of the invention described in the column of means for solving the problem is the same as that of the embodiment described in the column of means for solving the problem. Therefore, 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.

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

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

  20 hybrid vehicle, 22 engine, 24 engine electronic control unit (engine ECU), 26 crankshaft, 28 damper, 30 planetary gear, 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, 51 temperature sensor, 52 battery electronic control unit (battery ECU), 60 gear mechanism, 62 differential gear, 63a, 63b Drive wheel, 70 Hybrid electronic control unit (HVECU), 72 CPU, 74 ROM, 76 RAM, 80 Ignition switch, 81 Shift lever, 82 Shift position Sensor, 83 accelerator pedal, 84 an accelerator pedal position sensor, 85 brake pedal, 86 a brake pedal position sensor, 88 vehicle speed sensor, MG1, MG2 motor.

Claims (4)

An engine, a first motor, a drive shaft coupled to an axle, a planetary gear in which a ring gear, a carrier coupled to a plurality of pinion gears and a sun gear are coupled to the engine and the first motor, and a planetary gear coupled to the drive shaft A hybrid vehicle comprising: a second motor; and a battery that exchanges power with the first motor and the second motor,
A value obtained by subtracting the first margin from the upper limit rotational speed derived from the pinion gear, which is the upper limit rotational speed of the engine obtained from the performance of the pinion gear, and a lower rotational speed derived from the pinion gear, which is the lower limit rotational speed of the engine, obtained from the performance of the pinion gear. And a value obtained by adding a second margin to the engine, a target rotational speed of the engine is set within a range, and the engine and the first motor are configured to travel while the engine is operated using the set target rotational speed. Control means for controlling the second motor;
Wherein, Ri means der be set on the basis of at least one to the maximum allowable power of the battery of the first margin and the second margin,
Further, the control means includes an engine-derived upper limit rotational speed that is the upper limit rotational speed of the engine obtained from the performance of the engine and a first motor-derived upper limit that is the upper limit rotational speed of the engine obtained from the performance of the first motor. The minimum value of the rotational speed and the value obtained by subtracting the first margin from the upper limit rotational speed derived from the pinion gear, the value 0 as the lower limit rotational speed of the engine obtained from the performance of the engine, and the performance of the first motor The maximum number of the first motor-derived lower limit rotational speed, which is the lower limit rotational speed of the engine obtained from the above, and the value obtained by adding the second margin to the pinion gear-derived lower limit rotational speed is the rotational speed within the range. A means for controlling the engine to operate.
Hybrid car. The hybrid vehicle according to claim 1,
The control means is means for setting the first margin such that the absolute value of the maximum allowable input power of the battery tends to increase as the absolute value decreases.
Hybrid car. A hybrid vehicle according to claim 1 or 2,
The control means is means for setting the second margin so as to increase as the absolute value of the maximum allowable output power of the battery decreases.
Hybrid car. A hybrid vehicle according to claim 3,
The control means sets the second margin so that the absolute value of the maximum allowable output power of the battery tends to increase as the absolute value of the battery decreases and the absolute value of the maximum allowable input power of the battery decreases. Is,
Hybrid car.

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