JP2007190972A - Vehicle and control method therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enable a vehicle to travel by outputting more appropriate torque, without charging an electricity accumulating device, such as a battery with excessive power, when starting or low-speed traveling on an uphill. <P>SOLUTION: When a driver requests large torque at the starting or low-speed traveling on a slope with an ascending incline (S120), the lower limit number of revolutions Nmin and upper limit number of revolutions Nmax of an engine are calculated from a request power Pe*, within the range of the input limit Win of a battery or the status of a vehicle (S150 to S170), and the target number of revolutions Ne* of the engine is set as the number of revolutions for dividing the lower limit number of revolutions Nmin and the upper limit number of revolutions Nmax with inclination coefficients k, which are inclined to become smaller, according to as an inclination θ becomes larger (S190); and target torque Te* or torque commands Tm1* and Tm2* of motors MG1 and MG2 are set and controlled by using the target number of revolutions Ne* (S200 to S250). Thus, a vehicle can travel by outputting more appropriate torque. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

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

Conventionally, this type of vehicle includes an engine, a clutch motor that rotates by relative rotation between a first rotor connected to the output shaft of the engine and a second rotor connected to the axle, and power to the axle. Has been proposed (see, for example, Patent Document 1), which includes an assist motor that inputs / outputs and a clutch motor or a battery that exchanges power with the assist motor. In this vehicle, when starting on an uphill that requires a large torque or running at a low speed, the auxiliary machine is forcibly driven to increase the power from the engine, and when the battery charge power becomes greater than the maximum power allowed. The battery is prevented from being charged with excessive electric power by reducing the engine output speed and reducing the power output from the engine.
JP-A-9-266601

  In vehicles of the type that transmit power from the engine as traveling torque with power generation, such as the vehicle described above, if the engine is operated in advance to be within the battery input limit range, the charging power of the battery is In this case, the magnitude of the driving torque and the fuel consumption of the vehicle are affected depending on how the engine is operated.

  The vehicle and its control method according to the present invention provide an excessive power storage device such as a battery when starting uphill or traveling at a low speed in a vehicle of a type that transmits power from an internal combustion engine as traveling torque with power generation. One of the purposes is to output a more appropriate torque without being charged with a large amount of electric power. Further, the vehicle and the control method thereof according to the present invention provide a more appropriate torque when starting uphill or traveling at a low speed in a vehicle of a type that transmits power from the internal combustion engine as traveling torque with power generation. One of the purposes is to improve the fuel efficiency of the vehicle while outputting and traveling.

  The vehicle and the control method thereof according to the present invention employ the following means in order to achieve at least a part of the above-described object.

The vehicle of the present invention
An internal combustion engine;
An electric power input / output means connected to the output shaft and the axle of the internal combustion engine, for inputting / outputting power to / from the output shaft and the axle with input / output of electric power and power;
An electric motor capable of outputting driving power;
A power storage means capable of exchanging power with the electric power drive input / output means and the electric motor;
A gradient detecting means for detecting the gradient of the traveling path;
Required driving force setting means for setting required driving force required for traveling;
Target operating point setting means for setting a target operating point of the internal combustion engine based on the detected required driving force and the detected gradient;
Control means for controlling the internal combustion engine, the electric power drive input / output means, and the electric motor so that the internal combustion engine is operated at the set target operation point and travels with a driving force based on the set required driving force. When,
It is a summary to provide.

  In the vehicle of the present invention, a target operating point of the internal combustion engine is set based on the required driving force required for traveling and the gradient of the traveling path, and the internal combustion engine is operated at the set target operating point and requested driving is performed. The internal combustion engine, the power drive input / output means, and the electric motor are controlled so as to travel with a driving force based on the force. Thereby, the internal combustion engine can be operated according to the gradient of the travel path. As a result, it is possible to output a more appropriate driving force according to the gradient of the travel path and to improve the fuel consumption of the vehicle.

  In such a vehicle of the present invention, the target operating point setting means sets a target power to be output from the internal combustion engine based on the detected required driving force, and sets the target power and the detected gradient. It may be a means for setting a target operation point based on the above. In this way, the power corresponding to the required driving force can be output from the internal combustion engine at the operating point corresponding to the gradient of the travel path.

  In the vehicle of the present invention in which the target power is set by setting the target power, the vehicle is provided with an input limit setting means for setting an input limit that is an allowable maximum power when charging the power storage means, The setting means may be means for setting the target power within the set input restriction range. In this way, charging of the power storage means with excessive electric power can be suppressed.

  Further, in the vehicle of the present invention in which the target power is set by setting the target power, the target driving point setting means can output the set target power as the detected gradient increases as the climbing gradient. The target operation point setting means may be a means for setting the target operation point so that the torque output from the internal combustion engine tends to increase among the various operation points. As a larger value, the target operating point may be set so that the rotational speed of the internal combustion engine tends to decrease among the operating points at which the set target power can be output. In this way, it is possible to output a large torque from the internal combustion engine when the gradient of the traveling path is large as the climbing gradient, and to travel by transmitting a part of the large torque output from the internal combustion engine to the axle side. it can.

  Further, in the vehicle of the present invention in which the target power is set by setting the target power, an allowable rotational speed range that is a rotational speed range that allows the operation of the internal combustion engine is set based on the driving state of the vehicle. An allowable rotational speed range setting means may be provided, and the target operating point setting means may be means for setting a target operating point within the set allowable rotational speed range. If it carries out like this, an internal combustion engine can be drive | operated more appropriately. In this case, the allowable rotational speed range setting means sets a rotational speed equal to or higher than a minimum rotational speed at which the target power can be output from the internal combustion engine as a lower limit rotational speed of the allowable rotational speed range, and the power drive input / output means. Can be a means for setting a rotation speed equal to or lower than the maximum rotation speed of the internal combustion engine that can be driven as the upper limit rotation speed of the allowable rotation speed range.

  In the vehicle of the present invention, the power driving input / output means is connected to three shafts of an output shaft, an axle shaft, and a rotating shaft of the internal combustion engine, and inputs / outputs power to / from any two of the three shafts. And a power generator that can input and output power to the remaining shaft, and a generator that can input and output power to the rotary shaft.

The vehicle control method of the present invention includes:
An internal combustion engine, electric power input / output means connected to an output shaft and an axle of the internal combustion engine for inputting and outputting electric power and power to and from the output shaft and the axle, A vehicle control method comprising: an electric motor capable of outputting power; and an electric power input / output unit and an electric storage unit capable of exchanging electric power with the electric motor,
(A) setting a target operating point of the internal combustion engine based on a required driving force required for traveling and a gradient of the traveling path;
(B) The internal combustion engine is operated at the set target operation point, and the internal combustion engine, the electric power drive input / output means, and the electric motor are controlled so as to run with a driving force based on the required driving force. And

  In the vehicle control method of the present invention, a target operating point of the internal combustion engine is set based on the required driving force required for traveling and the gradient of the traveling path, and the internal combustion engine is operated at the set target operating point. At the same time, the internal combustion engine, the electric power drive input / output means, and the electric motor are controlled so as to travel with the driving force based on the required driving force. Thereby, the internal combustion engine can be operated according to the gradient of the travel path. As a result, it is possible to output a more appropriate driving force according to the gradient of the travel path and to improve the fuel consumption of the vehicle.

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

  FIG. 1 is a configuration diagram showing an outline of a configuration of a hybrid vehicle 20 equipped with a power output apparatus according to an embodiment of the present invention. As shown in the figure, the hybrid vehicle 20 of the embodiment includes an engine 22, a three-shaft power distribution / integration mechanism 30 connected to a crankshaft 26 as an output shaft of the engine 22 via a damper 28, and power distribution / integration. A motor MG1 capable of generating electricity connected to the mechanism 30, a reduction gear 35 attached to a ring gear shaft 32a as a drive shaft connected to the power distribution and integration mechanism 30, a motor MG2 connected to the reduction gear 35, And a hybrid electronic control unit 70 for controlling the entire power output apparatus.

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

  The power distribution and integration mechanism 30 includes an external gear sun gear 31, an internal gear ring gear 32 arranged concentrically with the sun gear 31, a plurality of pinion gears 33 that mesh with the sun gear 31 and mesh with the ring gear 32, A planetary gear mechanism is provided that includes a carrier 34 that holds a plurality of pinion gears 33 so as to rotate and revolve, and that performs differential action using the sun gear 31, the ring gear 32, and the carrier 34 as rotational elements. In the power distribution and integration mechanism 30, the crankshaft 26 of the engine 22 is connected to the carrier 34, the motor MG1 is connected to the sun gear 31, and the reduction gear 35 is connected to the ring gear 32 via the ring gear shaft 32a. When functioning as a generator, power from the engine 22 input from the carrier 34 is distributed according to the gear ratio between the sun gear 31 side and the ring gear 32 side, and when the motor MG1 functions as an electric motor, the engine input from the carrier 34 The power from 22 and the power from the motor MG1 input from the sun gear 31 are integrated and output to the ring gear 32 side. The power output to the ring gear 32 is finally output from the ring gear shaft 32a to the drive wheels 63a and 63b of the vehicle via the gear mechanism 60 and the differential gear 62.

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

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

  The hybrid electronic control unit 70 is configured as a microprocessor centered on the CPU 72, and in addition to the CPU 72, a ROM 74 for storing processing programs, a RAM 76 for temporarily storing data, an input / output port and communication not shown. And a port. The hybrid electronic control unit 70 includes an ignition signal from an ignition switch 80, a shift position SP from a shift position sensor 82 that detects the operation position of the shift lever 81, and an accelerator pedal position sensor 84 that detects the amount of depression of the accelerator pedal 83. From the brake pedal position BP that detects the depression amount of the brake pedal 85, the vehicle speed V from the vehicle speed sensor 88, and the gradient θ from the gradient sensor 89 that detects the gradient of the travel path. Etc. are input through the input port. As described above, the hybrid electronic control unit 70 is connected to the engine ECU 24, the motor ECU 40, and the battery ECU 52 via the communication port, and exchanges various control signals and data with the engine ECU 24, the motor ECU 40, and the battery ECU 52. ing.

  The hybrid vehicle 20 of the embodiment thus configured calculates the required torque to be output to the ring gear shaft 32a as the drive shaft based on the accelerator opening Acc and the vehicle speed V corresponding to the depression amount of the accelerator pedal 83 by the driver. Then, the operation of the engine 22, the motor MG1, and the motor MG2 is controlled so that the required power corresponding to the required torque is output to the ring gear shaft 32a. As operation control of the engine 22, the motor MG1, and the motor MG2, the operation of the engine 22 is controlled so that power corresponding to the required power is output from the engine 22, and all of the power output from the engine 22 is the power distribution and integration mechanism 30. Torque conversion operation mode for driving and controlling the motor MG1 and the motor MG2 so that the torque is converted by the motor MG1 and the motor MG2 and output to the ring gear shaft 32a, and the required power and the power required for charging and discharging the battery 50. The engine 22 is operated and controlled so that suitable power is output from the engine 22, and all or part of the power output from the engine 22 with charging / discharging of the battery 50 is the power distribution and integration mechanism 30, the motor MG1, and the motor. The required power is converted to the ring gear shaft 32 with torque conversion by MG2. Charge / discharge operation mode in which the motor MG1 and the motor MG2 are driven and controlled to be output to each other, and a motor operation mode in which the operation of the engine 22 is stopped and the power corresponding to the required power from the motor MG2 is output to the ring gear shaft 32a. and so on.

  Next, the operation of the hybrid vehicle 20 of the embodiment configured as described above, particularly the operation when starting on an uphill slope or traveling at a low speed will be described. FIG. 2 is a flowchart showing an example of a drive control routine executed by the hybrid electronic control unit 70. 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 hybrid electronic control unit 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 speed Nm1, of the motors MG1, MG2. A process of inputting data necessary for control, such as Nm2, the gradient θ from the gradient sensor 89, the input / output limits Win and Wout 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 from those calculated based on the rotational positions of the rotors of the motors MG1 and MG2 detected by the rotational position detection sensors 43 and 44. To do. The input / output limits Win and Wout of the battery 50 are set based on the temperature Tb of the battery 50 detected by the temperature sensor 51 and the remaining capacity (SOC) of the battery 50 from the battery ECU 52 by communication. It was supposed to be. The input / output limits Win and Wout of the battery 50 are set to the basic values of the input / output limits Win and Wout based on the battery temperature Tb, and the output limiting correction coefficient and the input are set based on the remaining capacity (SOC) of the battery 50. It can be set by setting a correction coefficient for restriction and multiplying the basic value of the set input / output restrictions Win and Wout by the correction coefficient. FIG. 3 shows an example of the relationship between the battery temperature Tb and the input / output limits Win, Wout, and FIG. 4 shows an example of the relationship between the remaining capacity (SOC) of the battery 50 and the correction coefficients of the input / output limits Win, Wout.

  When the data is thus input, the required torque Tr * to be output to the ring gear shaft 32a as the drive shaft connected to the drive wheels 63a and 63b as the torque required for the vehicle based on the input accelerator opening Acc and the vehicle speed V. Is set (step S110). In the embodiment, the required torque Tr * is determined in advance by storing the relationship between the accelerator opening Acc, the vehicle speed V, and the required torque Tr * in the ROM 74 as a required torque setting map, and the accelerator opening Acc, the vehicle speed V, , The corresponding required torque Tr * is derived and set from the stored map. FIG. 5 shows an example of the required torque setting map.

  Subsequently, it is determined whether or not the vehicle speed V is less than the threshold value Vref, whether or not the set required torque Tr * is equal to or greater than the threshold value Tref, and whether or not the vehicle is an uphill slope based on the gradient θ (step) S120). Here, the threshold value Vref is used to determine that the vehicle is running at a comparatively low speed, and for example, 10 km / h, 15 km / h, or the like can be used. Therefore, the process of comparing the vehicle speed V with the threshold value Vref determines whether the vehicle is starting or traveling at a low speed. The threshold value Tref is used to determine whether or not a relatively large torque is required. The threshold value Tref is a value such as 70% or 80% of the maximum torque that can be output when the vehicle speed V is 0. Can be used. Therefore, the process of comparing the required torque Tr * with the threshold value Tref determines whether or not the driver is requesting a large torque. Whether or not the slope is an uphill slope can be determined by determining whether or not the slope θ is equal to or greater than a preset threshold value θref. As the threshold value θref used in this case, 5 degrees or 7 degrees can be used.

  When it is determined that the vehicle speed V is equal to or higher than the threshold value Vref, the required torque Tr * is less than the threshold value Tref, or the slope is not an uphill slope, the required torque Tr * or the charge / discharge required power Pb required by the battery 50 is determined. *, The required power Pe * required for the engine 22 is set based on the auxiliary power Ph or the like (step S130), and the target rotational speed Ne * and the target torque Te of the engine 22 are set based on the set required power Pe *. * Is set (step S140). Here, the required power Pe * can be calculated as the sum of the required torque Tr * multiplied by the rotation speed Nr of the ring gear shaft 32a, the charge / discharge required power Pb *, the auxiliary power Ph, and the loss Loss. The rotation speed Nr of the ring gear shaft 32a can be obtained by multiplying the vehicle speed V by the conversion factor k, or can be obtained by dividing the rotation speed Nm2 of the motor MG2 by the gear ratio Gr of the reduction gear 35. The target rotational speed Ne * and the target torque Te * of the engine 22 are set based on the operation line for efficiently operating the engine 22 and the required power Pe *. FIG. 6 shows an example of the operation line of the engine 22 and how the target rotational speed Ne * and the target torque Te * are set. As shown in the figure, the target rotational speed Ne * and the target torque Te * can be obtained from the intersection of the operation line and a curve with a constant required power Pe * (Ne * × Te *).

  When the target rotational speed Ne * and the target torque Te * of the engine 22 are thus set, the set target rotational speed Ne *, the rotational speed Nr (Nm2 / Gr) of the ring gear shaft 32a, the gear ratio ρ of the power distribution and integration mechanism 30, and Is used to calculate the target rotational speed Nm1 * of the motor MG1 by the following formula (1), and based on the calculated target rotational speed Nm1 * and the current rotational speed Nm1, the torque command Tm1 * of the motor MG1 is calculated by the formula (2). Is calculated (step S210). Here, Expression (1) is a dynamic relational expression for the rotating element of the power distribution and integration mechanism 30. FIG. 7 is a collinear diagram showing a dynamic relationship between the number of rotations and torque in the rotating elements of the power distribution and integration mechanism 30. 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 obtained by dividing the number Nm2 by the gear ratio Gr of the reduction gear 35 is shown. Expression (1) can be easily derived by using this alignment chart. The two thick arrows on the R axis indicate that the torque Tm1 output from the motor MG1 acts on the ring gear shaft 32a and the torque Tm2 output from the motor MG2 acts on the ring gear shaft 32a via the reduction gear 35. Torque. Expression (2) is a relational expression in the feedback control for rotating the motor MG1 at the target rotational speed Nm1 *. In the expression (2), “k1” in the second term on the right side is the gain of the proportional term, and the right side The third term “k2” is the gain of the integral term.

Nm1 * = Ne * ・ (1 + ρ) / ρ-Nm2 / (Gr ・ ρ) (1)
Tm1 * = previous Tm1 * + k1 (Nm1 * -Nm1) + k2∫ (Nm1 * -Nm1) dt (2)

  When the target rotational speed Nm1 * and the torque command Tm1 * of the motor MG1 are thus calculated, the input / output limits Win and Wout of the battery 50 and the calculated torque command Tm1 * of the motor MG1 are multiplied by the current rotational speed Nm1 of the motor MG1. 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 obtained power consumption (generated power) of the motor MG1 by the rotational speed Nm2 of the motor MG2 is expressed by the following equation (3). In addition, the temporary motor torque Tm2tmp as the torque to be output from the motor MG2 is calculated using the required torque Tr *, the torque command Tm1 *, and the gear ratio ρ of the power distribution and integration mechanism 30 (step S220). Calculated by equation (5) (step S230), and with the calculated torque limits Tmin, Tmax Setting the torque command Tm2 * of the motor MG2 as a value obtained by limiting the motor torque Tm2tmp (step S240). By setting the torque command Tm2 * of the motor MG2 in this way, the required torque Tr * output to the ring gear shaft 32a as the drive shaft is set as a torque limited within the range of the input / output limits Win and Wout of the battery 50. can do. Equation (5) can be easily derived from the collinear diagram of FIG. 7 described above.

Tmin = (Win-Tm1 * ・ Nm1) / Nm2 (3)
Tmax = (Wout-Tm1 * ・ Nm1) / Nm2 (4)
Tm2tmp = (Tr * + Tm1 * / ρ) / Gr (5)

  Thus, when the target engine speed Ne *, the target torque Te *, and the torque commands Tm1 *, Tm2 * of the motors MG1, MG2 are set, the target engine speed Ne * and the target torque Te * of the engine 22 are set in the engine ECU 24. Torque commands Tm1 * and Tm2 * for motors MG1 and MG2 are transmitted to motor ECU 40 (step S250), and the drive control routine is terminated. The engine ECU 24 that has received the target rotational speed Ne * and the target torque Te * performs fuel injection control in the engine 22 such that the engine 22 is operated at an operating point indicated by the target rotational speed Ne * and the target torque Te *. Controls such as ignition control. The motor ECU 40 that has received the torque commands Tm1 * and Tm2 * controls the switching elements of the inverters 41 and 42 so that the motor MG1 is driven by the torque command Tm1 * and the motor MG2 is driven by the torque command Tm2 *. To do.

  When it is determined in step S120 that the vehicle speed V is less than the threshold value Vref, the required torque Tr * is greater than or equal to the threshold value Tref, and the slope is an uphill slope, that is, at the start of the uphill slope or at low speed When it is determined that the driver is requesting a large torque, the input limit of the battery 50 is determined based on the required torque Tr * multiplied by the rotational speed Nr of the ring gear shaft 32a as shown in the following equation (6). The required power Pe * is set as a value obtained by subtracting Win and adding the loss Loss (step S150), and the lower limit rotational speed Nmin of the engine 22 is set based on the set required power Pe * and the power line (step S160). ), The upper limit rotational speed Nma of the engine 22 based on the maximum rotational speed Nm1max of the motor MG1 and the rotational speed Nr of the ring gear shaft 32a. The set (step S170). Here, the power line is an operation line set as an operation point at which the maximum torque is output from the engine 22 when the engine 22 is operated at the same rotational speed. An example of the power line is shown in FIG. 8 together with a normal operation line (an optimum fuel efficiency operation line). The lower limit rotational speed Nmin of the engine 22 can be obtained as the rotational speed at the intersection of this power line and the required power Pe *. The upper limit rotational speed Nmax of the engine 22 can be obtained as the rotational speed of the engine 22 when the motor MG1 is operated at the allowable maximum rotational speed Nm1max with respect to the rotational speed Nr of the ring gear shaft 32a corresponding to the current vehicle speed V. And can be calculated by equation (7). FIG. 9 shows an example of a collinear diagram showing the relationship among the rotational speed Nr of the ring gear shaft 32a, the maximum rotational speed Nm1max of the motor MG1, and the upper limit rotational speed Nmax of the engine 22. The lower limit rotational speed Nmin and the upper limit rotational speed Nmax of the engine 22 set an allowable rotational speed range in which the engine 22 can be operated.

Pe * = Tr * ・ Nr-Win + Loss (6)
Nmax = (Nr + ρ ・ Nm1max) / (1 + ρ) (7)

  Based on the gradient θ, a gradient coefficient k for proportionally dividing the lower limit rotational speed Nmin and the upper limit rotational speed Nmax is set (step S180), and the lower limit rotational speed Nmin and the upper limit rotational speed Nmax are apportioned by this gradient coefficient k. The target rotational speed Ne * of the engine 22 is set as the rotational speed to be performed (step S190), and the target power Te * is divided by the set target rotational speed Ne * to set the target torque Te * of the engine 22 (step S200). ). Then, using the set target rotational speed Ne * and the target torque Te *, torque commands Tm1 * and Tm2 * for the motors MG1 and MG2 are set as described above (steps S210 to S240), and the set values are set in the engine ECU 24 or It transmits to motor ECU40 (step S250), and this routine is complete | finished. Here, in the embodiment, the gradient coefficient k is set so as to decrease as the gradient θ increases. FIG. 10 shows an example of the relationship between the gradient θ and the gradient coefficient k. Since the target rotational speed Ne * of the engine 22 is set by apportioning the lower limit rotational speed Nmin and the upper limit rotational speed Nmax with the gradient coefficient k, the target rotational speed Ne * of the engine 22 tends to decrease as the gradient θ increases. Will be set to. An example of the relationship between the gradient θ and the target rotational speed Ne * of the engine 22 is shown in FIG. When the gradient θ is large, the target rotational speed Ne * of the engine 22 is set small, and accordingly, the target torque Te * is set large. For this reason, the torque command Tm1 * of the motor MG1 is also set to be large, and the torque that is output from the motor MG1 acts on the ring gear shaft 32a also increases. As a result, a large torque can be applied to the ring gear shaft 32a. Note that the relationship in which the target rotational speed Ne * of the engine 22 tends to decrease as the gradient θ increases is a relationship in which the target torque Te * of the engine 22 tends to increase as the gradient θ increases.

  According to the hybrid vehicle 20 of the embodiment described above, the required power Pe that falls within the range of the input limit Win of the battery 50 when the driver is requesting a large torque when starting on an uphill slope or traveling at a low speed. Since the target rotational speed Ne * and the target torque Te * of the engine 22 corresponding to the gradient θ are set using *, the engine 22 and the motor MG1 are controlled according to the gradient θ without charging the battery 50 with excessive electric power. , MG2 can be controlled to output a torque based on the required torque Tr * corresponding to the accelerator opening Acc to the ring gear shaft 32a. That is, more appropriate control can be performed according to the gradient θ. As a result, it is possible to output a more appropriate torque as compared with the engine 22 for setting the target rotational speed Ne * and the target torque Te * regardless of the gradient θ, and to improve the fuel efficiency of the vehicle. Can be improved. Moreover, since the target rotational speed Ne * of the engine 22 is set within the range between the lower limit rotational speed Nmin and the upper limit rotational speed Nmax, inconvenience due to trying to operate the engine 22 at a rotational speed less than the lower limit rotational speed Nmin (engine 22 and the like, and inconvenience (such as over-rotation of the motor MG1) caused by trying to operate the engine 22 at a rotational speed exceeding the upper limit rotational speed Nmax can be suppressed.

  In the hybrid vehicle 20 of the embodiment, when the driver is requesting a large torque at the start of an ascending slope or when traveling at a low speed, the required power Pe * that falls within the range of the input limit Win of the battery 50 is used. The target rotational speed Ne * and target torque Te * of the engine 22 corresponding to the gradient θ are set. However, when starting on an uphill slope or driving at a low speed, it is required regardless of the torque required by the driver. The target speed Ne * and the target torque Te * of the engine 22 corresponding to the gradient θ may be set using the power Pe *, or when the driver is requesting a large torque on an uphill slope Regardless of when starting or running at a low speed, the target rotational speed Ne * and the target torque Te * of the engine 22 corresponding to the gradient θ may be set using the required power Pe *. When traveling on a slope with a slope, the target rotational speed of the engine 22 corresponding to the slope θ using the required power Pe * regardless of whether the vehicle is starting or traveling at a low speed and regardless of the torque requested by the driver. Ne * and target torque Te * may be set.

  In the hybrid vehicle 20 of the embodiment, when the driver requests a large torque at the start of an uphill slope or at a low speed, the lower limit rotation of the engine 22 is set as the rotation speed of the intersection of the required power Pe * and the power line. Although the number Nmin is set, the lower limit rotational speed Nmin of the engine 22 may be set to a rotational speed larger than the rotational speed at the intersection of the required power Pe * and the power line.

  In the hybrid vehicle 20 of the embodiment, when the driver requests a large torque at the start of an uphill slope or at a low speed, the motor MG1 is used for the rotational speed Nr of the ring gear shaft 32a corresponding to the current vehicle speed V. Is set as the upper limit rotational speed Nmax of the engine 22, but the motor MG1 is allowed with respect to the rotational speed Nr of the ring gear shaft 32a. A rotational speed smaller than the rotational speed of the engine 22 when operating at the maximum rotational speed Nm1max may be set as the upper limit rotational speed Nmax of the engine 22.

  In the hybrid vehicle 20 of the embodiment, when the driver is requesting a large torque at the start of an ascending slope or when driving at a low speed, the lower limit rotation speed Nmin and the upper limit rotation speed Nmax are set with the gradient coefficient k based on the gradient θ. The target engine speed Ne * of the engine 22 is set as the apportioning engine speed. However, the engine speed is slightly different based on the gradient θ with respect to the engine speed at the intersection of the required power Pe * and the fuel efficiency optimum operation line used in normal operation. A value that is increased or decreased by the rotational speed may be set as the target rotational speed Ne * of the engine 22. In this case, the target rotational speed Ne * may be reduced as the gradient θ increases. Further, if such a method for setting the target engine speed Ne * of the engine 22 is used, it is not necessary to set the lower limit engine speed Nmin and the upper engine speed Nmax of the engine 22, and it is not necessary to obtain the gradient coefficient k.

  In the hybrid vehicle 20 of the embodiment, when the driver is requesting a large torque at the start of an ascending slope or when driving at a low speed, the lower limit speed Nmin and the upper limit speed Nmax of the engine 22 are obtained and the slope θ is obtained. The target rotational speed Ne * of the engine 22 is set as a rotational speed that apportions the lower limit rotational speed Nmin and the upper limit rotational speed Nmax obtained by the gradient coefficient k, and the target torque Te * is set using the target rotational speed Ne *. However, the lower limit torque Tmin and the upper limit torque Tmax of the engine 22 are obtained, and the target torque Te * of the engine 22 is obtained as a torque that apportions the lower limit torque Tmin and the upper limit torque Tmax obtained by the gradient coefficient k based on the gradient θ. And the target rotational speed Ne * may be set using the target torque Te *. In this case, the lower limit torque Tmin of the engine 22 can be set as a torque corresponding to the upper limit speed Nmax of the engine 22, and the upper limit torque Tmax of the engine 22 is set as a torque corresponding to the lower limit speed Nmin of the engine 22. be able to.

  In the hybrid vehicle 20 of the embodiment, the power of the motor MG2 is shifted by the reduction gear 35 and output to the ring gear shaft 32a. However, as illustrated in the hybrid vehicle 120 of the modified example of FIG. May be connected to an axle (an axle connected to the wheels 64a and 64b in FIG. 12) different from the axle to which the ring gear shaft 32a is connected (the axle to which the drive wheels 63a and 63b are connected).

  In the hybrid vehicle 20 of the embodiment, the power of the engine 22 is output to the ring gear shaft 32a as the drive shaft connected to the drive wheels 63a and 63b via the power distribution and integration mechanism 30, but the modified example of FIG. The hybrid vehicle 220 includes an inner rotor 232 connected to the crankshaft 26 of the engine 22 and an outer rotor 234 connected to a drive shaft that outputs power to the drive wheels 63a and 63b. A counter-rotor motor 230 that transmits a part of the power to the drive shaft and converts the remaining power into electric power may be provided.

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

  The embodiments of the present invention have been described using the embodiments. However, the present invention is not limited to these embodiments, and can be implemented in various forms without departing from the gist of the present invention. Of course you get.

  The present invention can be used in the vehicle manufacturing industry.

1 is a configuration diagram showing an outline of a configuration of a hybrid vehicle 20 according to an embodiment of the present invention. It is a flowchart which shows an example of the drive control routine performed by the electronic control unit for hybrids 70 of an Example. It is explanatory drawing which shows an example of the relationship between the battery temperature Tb in the battery 50, and the input / output restrictions Win and Wout. It is explanatory drawing which shows an example of the relationship between the remaining capacity (SOC) of the battery 50, and the correction coefficient of input / output restrictions Win and Wout. It is explanatory drawing which shows an example of the map for request | requirement torque setting. It is explanatory drawing which shows a mode that an example of the operating line of the engine 22, and target rotational speed Ne * and target torque Te * are set. FIG. 4 is an explanatory diagram showing an example of a collinear diagram for dynamically explaining rotational elements of a power distribution and integration mechanism 30; It is explanatory drawing which shows an example of a power line with a normal operation line. FIG. 4 is an explanatory diagram showing an example of a collinear diagram showing a relationship among a rotational speed Nr of a ring gear shaft 32a, a maximum rotational speed Nm1max of a motor MG1, and an upper limit rotational speed Nmax of an engine 22. It is explanatory drawing which shows an example of the relationship between gradient (theta) and gradient coefficient k. It is explanatory drawing which shows the relationship between gradient (theta) and the rotation speed Ne of the engine. FIG. 11 is a configuration diagram showing an outline of a configuration of a hybrid vehicle 120 according to a modification. FIG. 11 is a configuration diagram showing an outline of a configuration of a hybrid vehicle 220 of a modified example.

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, 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), 54 power line , 60 gear mechanism, 62 differential gear, 63a, 63b drive wheel, 64a, 64b wheel, 70 electronic control unit for hybrid, 72 CPU, 74 ROM, 76 RAM, 80 ignition switch, 81 shift lever , 82 Shift position sensor, 83 Accelerator pedal, 84 Accelerator pedal position sensor, 85 Brake pedal, 86 Brake pedal position sensor, 88 Vehicle speed sensor, 89 Gradient sensor, 230 Counter rotor motor, 232 Inner rotor, 234 Outer rotor, MG1, MG2 motor.

Claims (9)

An internal combustion engine;
An electric power input / output means connected to the output shaft and the axle of the internal combustion engine, for inputting / outputting power to / from the output shaft and the axle with input / output of electric power and power;
An electric motor capable of outputting driving power;
A power storage means capable of exchanging power with the electric power drive input / output means and the electric motor;
A gradient detecting means for detecting the gradient of the traveling path;
Required driving force setting means for setting required driving force required for traveling;
Target operating point setting means for setting a target operating point of the internal combustion engine based on the detected required driving force and the detected gradient;
Control means for controlling the internal combustion engine, the electric power drive input / output means, and the electric motor so that the internal combustion engine is operated at the set target operation point and travels with a driving force based on the set required driving force. When,
A vehicle comprising:   The target operating point setting means sets a target power to be output from the internal combustion engine based on the detected required driving force, and sets a target operating point based on the set target power and the detected gradient. The vehicle according to claim 1, which is means for setting. The vehicle according to claim 2,
Input limit setting means for setting an input limit that is an allowable maximum power when charging the power storage means,
The target operation point setting means is means for setting the target power within the set input restriction range.   The target operating point setting means sets the target operating point so that the torque output from the internal combustion engine tends to increase among the operating points capable of outputting the set target power as the detected gradient increases as the climbing gradient. 4. The vehicle according to claim 2, wherein the vehicle is a means for   The target operating point setting means sets the target operating point such that the rotational speed of the internal combustion engine tends to decrease among the operating points capable of outputting the set target power as the detected gradient increases as the climbing gradient. The vehicle according to claim 2 or 3, which is means. A vehicle according to any one of claims 2 to 5,
An allowable rotational speed range setting means for setting an allowable rotational speed range that is a rotational speed range that allows the operation of the internal combustion engine based on a driving state of the vehicle;
The target operation point setting means is a means for setting a target operation point within the set allowable rotational speed range.   The allowable rotational speed range setting means sets a rotational speed that is equal to or higher than the minimum rotational speed at which the target power can be output from the internal combustion engine as a lower limit rotational speed of the allowable rotational speed range, and can drive the power drive input / output means. 7. The vehicle according to claim 6, wherein the vehicle is means for setting a rotation speed equal to or lower than a maximum rotation speed of the internal combustion engine as an upper limit rotation speed of the allowable rotation speed range.   The power power input / output means is connected to three shafts of an output shaft, an axle shaft, and a rotating shaft of the internal combustion engine, and power is supplied to the remaining shaft based on power input / output to / from any two of the three shafts. The vehicle according to any one of claims 1 to 7, further comprising: a three-axis power input / output means for inputting / outputting power; and a generator capable of inputting / outputting power to / from the rotating shaft. An internal combustion engine, electric power input / output means connected to an output shaft and an axle of the internal combustion engine for inputting and outputting electric power and power to and from the output shaft and the axle, A vehicle control method comprising: an electric motor capable of outputting power; and an electric power input / output unit and an electric storage unit capable of exchanging electric power with the electric motor,
(A) setting a target operating point of the internal combustion engine based on a required driving force required for traveling and a gradient of the traveling path;
(B) The internal combustion engine is operated at the set target operation point, and the internal combustion engine, the electric power drive input / output means, and the electric motor are controlled so as to run with a driving force based on the required driving force. Method.

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