JP5751192B2 - Hybrid car - Google Patents

Description

  The present invention relates to a hybrid vehicle, and more specifically, three rotation elements are connected to three axes of an engine, a first motor, a drive shaft coupled to an axle, an output shaft of the engine, and a rotation shaft of the first motor. The present invention relates to a hybrid vehicle including a planetary gear, a second motor having a rotation shaft 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 internal combustion engine as one of prime movers, a first motor generator (motor MG1), a drive shaft connected to drive wheels, an output shaft of the internal combustion engine, and a rotor of the motor MG1. A planetary gear connected to each other, a second motor generator (motor MG2) as one of the prime movers whose rotor is connected to the drive shaft, and a secondary battery electrically connected to the motor MG1 and the motor MG2. In a preset vehicle speed range, inertial traveling that travels inertially with deceleration to its lower limit vehicle speed, and accelerated traveling that travels with acceleration to the upper limit vehicle speed by power from the prime mover, One that repeatedly performs accelerated inertial running has been proposed (see, for example, Patent Document 1). In this hybrid vehicle, the internal combustion engine is operated during acceleration, and the internal combustion engine is driven in an efficient driving state by outputting power for accelerating the vehicle and charging the battery from the internal combustion engine. .

JP 2010-6309 A

  In a hybrid vehicle configured in the same manner as described above, it has been considered that one of the problems is to increase the traveling distance by inertial traveling in accelerated inertial traveling. When the travel distance due to inertial traveling is short, the vehicle is frequently decelerated and accelerated, giving the driver a sense of incongruity, and increasing the frequency at which the engine is started during accelerated inertial travel, resulting in energy efficiency (fuel consumption) There is a possibility that inconveniences such as the inability to improve the quality may occur.

  The main purpose of the hybrid vehicle of the present invention is to make the distance traveled with the inertial force of the vehicle longer while the torque output from the second motor is stopped.

  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 planetary gear in which three rotation elements are connected to three axes of a drive shaft coupled to an axle, an output shaft of the engine, and a rotation shaft of the first motor, and rotation to the drive shaft A hybrid vehicle comprising: a second motor to which a shaft is connected; and a battery that exchanges electric power with the first motor and the second motor,
During the second motor intermittent operation traveling in which the torque output from the second motor and the output stop are repeated to travel within a predetermined vehicle speed range, the torque output from the second motor is stopped. Motor intermittent control means for controlling the first motor and the second motor so as to travel by outputting a vehicle speed decrease suppression torque in a direction to suppress a decrease in vehicle speed from the first motor;
It is a summary to provide.

  In the hybrid vehicle according to the present invention, when the second motor intermittently travels within a predetermined vehicle speed range by repeatedly outputting torque from the second motor and stopping the output, torque from the second motor is used. When the output is stopped, the first motor and the second motor are controlled so that the vehicle travels by outputting a vehicle speed decrease suppression torque in a direction to suppress a decrease in vehicle speed from the first motor. Thereby, a decrease in the vehicle speed can be suppressed while the torque output from the second motor is stopped when the second motor intermittent operation travel is performed, and the inertial force of the vehicle while the torque output from the second motor is stopped. The distance (time) traveled with can be made longer.

  Here, as the “vehicle speed reduction suppression torque”, for example, when a predetermined constant torque is used, a torque based on the vehicle speed is used, or when the engine operation is stopped, the engine does not reversely rotate. A constant torque determined within the range or a torque based on the vehicle speed may be used. In addition, as the “predetermined vehicle speed width”, for example, a predetermined vehicle speed width is used, or a vehicle speed width that tends to increase as the vehicle speed when starting the second motor intermittent operation is increased. It may be a thing. Further, the “second motor intermittent operation running” may be performed in a state where the operation of the engine is stopped, may be performed in a state where the engine is operated in a predetermined target state, The operation may be performed while the engine is started and operated while the torque is output from the two motors, and while the operation of the engine is stopped while the output of the torque from the second motor is stopped.

  In such a hybrid vehicle of the present invention, when the motor intermittent control means outputs a vehicle speed reduction suppression torque from the first motor and a predetermined prediction condition that the vehicle's energy efficiency is predicted to decrease is satisfied, The torque output from the first motor while the torque output from the second motor is stopped may be a means for controlling the torque to be limited by the vehicle speed decrease suppression torque. In this way, when the output of the torque from the second motor is stopped when the second motor is intermittently operated, the vehicle speed reduction suppression torque is output from the first motor, thereby suppressing the reduction of the vehicle energy efficiency. can do.

  In the hybrid vehicle according to the aspect of the invention in which the torque output from the first motor is limited by the vehicle speed reduction suppression torque while the output of the torque from the second motor is stopped when the predetermined prediction condition is satisfied, the motor intermittent The control means is means for controlling the engine so as to travel in a state in which the operation of the engine is stopped, and the predetermined prediction condition is a condition that a storage amount of the battery is less than a predetermined threshold value; It is also possible to use at least one of the predetermined battery prediction conditions in which recovery of the storage amount of the battery is not predicted. In the case of traveling with the engine operation stopped when performing the second motor intermittent operation traveling, the negative motor in the direction of suppressing the decrease in vehicle speed from the first motor while the torque output from the second motor is stopped. When torque is output, the amount of power stored in the battery is likely to decrease due to power consumption by the first motor. Therefore, when the amount of electricity stored in the battery is relatively small, or when recovery of the amount of electricity stored in the battery is not predicted due to power regeneration by the second motor accompanying downhill travel or braking, output of torque from the second motor is stopped. By limiting the output of the negative torque from the first motor in the middle, it is possible to suppress the power consumption by the first motor and suppress the decrease in the amount of power stored in the battery.

  Further, in the hybrid vehicle of the present invention, the motor intermittent control means starts outputting the predetermined intermittent operation torque from the second motor when the vehicle speed decreases to the lower limit value of the predetermined vehicle speed width. The second motor may be a means for controlling the second motor so that the torque output from the second motor is stopped when the vehicle speed increases to the upper limit value of the predetermined vehicle speed width. Here, as the “predetermined intermittent operation torque”, for example, a torque that tends to increase as the vehicle speed increases when the second motor intermittent operation traveling is started may be used.

1 is a configuration diagram showing an outline of a configuration of a hybrid vehicle 20 as an embodiment of the present invention. 5 is a flowchart illustrating an example of a motor intermittent operation travel control routine executed by an HVECU 70; A collinear diagram showing the mechanical relationship between the rotational speed and torque of the rotating element of the planetary gear 30 when traveling with the output of torque from the motor MG2 being stopped with the output of torque on the negative side from the motor MG1. It is explanatory drawing which shows an example. It is explanatory drawing which shows an example of the collinear diagram which shows the dynamic relationship of the rotation speed and torque in the rotation element of the planetary gear 30 when driving | running | working by outputting torque from motor MG2. It is explanatory drawing which shows an example of the time change state of the vehicle speed V, the output torque Tm2 from the motor MG2, and the output torque Tm1 from the motor MG1 when traveling in the motor intermittent operation mode. In the modified example, the mechanical relationship between the rotational speed and the torque of the rotating element of the planetary gear 30 when traveling with the torque output from the motor MG2 stopped together with the output of the negative torque from the motor MG1 is shown. It is explanatory drawing which shows an example of an alignment chart. FIG. 11 is a configuration diagram showing an outline of a configuration of a hybrid vehicle 120 according to a modification.

  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 figure, the hybrid vehicle 20 of the embodiment includes an engine 22 that uses gasoline or light oil as fuel, an engine electronic control unit (hereinafter referred to as engine ECU) 24 that controls the drive of the engine 22, and a crank of the engine 22. A planetary gear 30 having a carrier connected to the shaft 26 and a ring gear connected to a drive shaft 36 connected to drive wheels 38a and 38b via a differential gear 37, and a rotor configured as a synchronous generator motor, for example. A motor MG1 connected to the sun gear, a motor MG2 configured as a synchronous generator motor and having a rotor connected to the drive shaft 36, inverters 41 and 42 for driving the motors MG1 and MG2, an inverter 41, 42 by controlling the motor MG1, A motor electronic control unit (hereinafter referred to as a motor ECU) 40 for driving and controlling G2, and a battery 50 configured as, for example, a lithium ion secondary battery that exchanges power with the motors MG1 and MG2 via inverters 41 and 42; A battery electronic control unit (hereinafter referred to as a battery ECU) 52 for managing the battery 50, a hybrid electronic control unit (hereinafter referred to as an HVECU) 70 for controlling the entire vehicle, and a travel route are set using map data. And a navigation device 90 that provides route guidance for the set travel route.

  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 water temperature sensor that detects the crank position θcr from the crank position sensor that detects the rotational position of the crankshaft 26 and the coolant temperature of the engine 22. From the cam position sensor for detecting the cooling water temperature Tw from the cylinder, the in-cylinder pressure Pin from the pressure sensor installed in the combustion chamber, the rotational position of the intake valve for intake and exhaust to the combustion chamber and the camshaft for opening and closing the exhaust valve Position θca, throttle position SP from a throttle valve position sensor for detecting the position of the throttle valve, intake air amount Qa from an air flow meter attached to the intake pipe, intake air temperature Ta from a temperature sensor also attached to the intake pipe, Installed in the exhaust system The air-fuel ratio AF from the air-fuel ratio sensor and the oxygen signal O2 from the oxygen sensor attached to the exhaust system are input via the input port, and the engine ECU 24 is for driving the engine 22. Various control signals, such as the drive signal to the fuel injection valve, the drive signal to the throttle motor that adjusts the throttle valve position, the control signal to the ignition coil integrated with the igniter, and the opening / closing timing of the intake valve can be changed A control signal to the variable valve timing mechanism is output via the 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 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.

  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 receives signals necessary for managing the battery 50, for example, an inter-terminal voltage Vb from a voltage sensor (not shown) installed between the terminals of the battery 50 and a power line connected to the output terminal of the battery 50. The charging / discharging current Ib from the attached current sensor (not shown), the battery temperature Tb from the temperature sensor (not shown) attached to the battery 50, and the like are input. Send to. Further, the battery ECU 52 controls the 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 to manage the battery 50 (the battery 50 I / O limit Win, which is the maximum allowable power that may be charged / discharged based on the calculated storage ratio SOC and the battery temperature Tb. Wout is calculated. 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 limiting limit are set based on the storage ratio SOC of the battery 50. It can be set by setting a correction coefficient and multiplying the basic value of the set input / output limits Win and Wout by the correction coefficient.

  Although not shown, the HVECU 70 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 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, brake pedal position BP from the brake pedal position sensor 86 that detects the amount of depression of the brake pedal 85, vehicle speed V from the vehicle speed sensor 88, intermittent output of torque from the motor MG2 and output stop of the motor A signal from an instruction switch 89 for instructing traveling in the mode is input through 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 road data such as road position, distance, gradient, and altitude, and facility data such as the position and type of the facility. Are connected via a communication port to a navigation device 90 for setting and guiding a travel route using map data, and exchange of various control signals and data with the engine ECU 24, motor ECU 40, battery ECU 52, and navigation device 90. Is doing.

  The hybrid vehicle 20 of the embodiment thus configured calculates the required torque Tr * to be output to the drive shaft 36 based on the accelerator opening Acc and the vehicle speed V corresponding to the amount of depression of the accelerator pedal by the driver. 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 Tr * is output to the drive shaft 36. As basic 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 the power output from the engine 22 is planetary gear 30. Torque conversion operation mode in which the motor MG1 and the motor MG2 are driven and controlled so that the torque is converted by the motor MG1 and the motor MG2 and output to the drive shaft 36, and the sum of the required power and the power required for charging and discharging the battery 50 The engine 22 is operated and controlled so that the power corresponding to the power is output from the engine 22, and all or a part of the power output from the engine 22 with charging / discharging of the battery 50 is transmitted to the planetary gear 30, the motor MG1, and the motor MG2. The required power is output to the drive shaft 36 with torque conversion by There are a charge / discharge operation mode for driving and controlling the motor MG1 and the motor MG2 and a motor operation mode for controlling the operation so that the operation of the engine 22 is stopped and power corresponding to the required power from the motor MG2 is output to the drive shaft 36. . The torque conversion operation mode and the charge / discharge operation mode are modes in which the engine 22 and the motors MG1, MG2 are controlled so that the required power is output to the drive shaft 36 with the operation of the engine 22. Since there is no difference in general control, both are hereinafter referred to as an engine operation mode.

  In the engine operation mode, the HVECU 70 sets the required torque Tr * to be output to the drive shaft 36 based on the accelerator opening Acc from the accelerator pedal position sensor 84 and the vehicle speed V from the vehicle speed sensor 88, and the set required torque The travel power Pdrv * required for travel is calculated by multiplying Tr * by the rotational speed Nr of the drive shaft 36 (for example, the rotational speed obtained by multiplying the rotational speed Nm2 of the motor MG2 and the vehicle speed V by the conversion factor). The power to be output from the engine 22 by subtracting the charge / discharge required power Pb * (positive value when discharging from the battery 50) of the battery 50 obtained from the calculated traveling power Pdrv * based on the storage ratio SOC of the battery 50 Is set as the required power Pe *. Then, the target rotational speed Ne of the engine 22 is obtained using an operation line (for example, a fuel efficiency optimal operation line) as a relationship between the rotational speed Ne of the engine 22 and the torque Te that can efficiently output the required power Pe * from the engine 22. * And target torque Te * are set, and the motor is controlled by rotation speed feedback control so that the rotation speed Ne of the engine 22 becomes the target rotation speed Ne * within the range of the input / output limits Win and Wout of the battery 50. A torque command Tm1 * as a torque to be output from MG1 is set, and when the motor MG1 is driven by the torque command Tm1 *, the torque acting on the drive shaft 36 via the planetary gear 30 is subtracted from the required torque Tr * to reduce the motor MG2. Torque command Tm2 * is set, and the target rotational speed Ne * and target torque Te * are set. In its sent to the engine ECU 24, the torque command Tm1 *, the Tm2 * is sent to the motor ECU 40. The engine ECU 24 that has received the target rotational speed Ne * and the target torque Te *, controls the intake air amount, fuel injection control, and ignition of the engine 22 so that the engine 22 is operated by the target rotational speed Ne * and the target torque Te *. The motor ECU 40 that performs control or the like and receives the torque commands Tm1 * and Tm2 * 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 *.

  In the motor operation mode, the HVECU 70 sets a required torque Tr * to be output to the drive shaft 36 based on the accelerator opening Acc and the vehicle speed V, sets a value 0 to the torque command Tm1 * of the motor MG1, and sets the battery 50. The torque command Tm2 * of the motor MG2 is set and transmitted to the motor ECU 40 so that the required torque Tr * is output to the drive shaft 36 within the range of the input / output limits Win, Wout. Then, the motor ECU 40 that receives the torque commands Tm1 * and Tm2 * 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 *.

  Next, the operation of the hybrid vehicle 20 of the embodiment, in particular, the operation at the time of traveling in the motor intermittent operation mode that travels by repeatedly outputting the torque from the motor MG2 and stopping the output (hereinafter also referred to as motor intermittent operation traveling). Will be described. FIG. 2 is a flowchart showing an example of a motor intermittent operation travel control routine executed by the HVECU 70. This routine is executed when a predetermined start condition for starting traveling in the motor intermittent operation mode is satisfied. In the embodiment, the predetermined start condition is that the instruction switch 89 is turned on in a state where the fluctuation amount of the vehicle speed V from the vehicle speed sensor 88 is within a predetermined range indicating the stability of the vehicle speed V in the motor operation mode. Conditions were used.

  When the motor intermittent operation travel control routine is executed, the HVECU 70 first transmits a control signal to the engine ECU 24 so as to keep the operation of the engine 22 stopped (step S100), and the vehicle speed from the vehicle speed sensor 88 is transmitted. A process of inputting V and setting the input vehicle speed V as the starting vehicle speed V1 is executed (step S110). The engine ECU 24 that has received the control signal maintains a state in which the operation control of the engine 22 such as fuel injection control and ignition control is stopped so that the state in which the operation of the engine 22 is stopped is maintained.

  Subsequently, a control vehicle speed width ΔV for setting an upper limit vehicle speed Vmax and a lower limit vehicle speed Vmin when traveling in the motor intermittent operation mode is set based on the set start time vehicle speed V1 (step S120). The upper limit vehicle speed Vmax and the lower limit vehicle speed Vmin are set by the following equations (1) and (2) using the control vehicle speed width ΔV and the starting vehicle speed V1 (step S130). In the embodiment, the control vehicle speed width ΔV is stored in a ROM (not shown) as a control vehicle speed width setting map by predetermining the relationship between the start vehicle speed V1 and the control vehicle speed width ΔV, and given the start vehicle speed V1. The corresponding control vehicle speed width ΔV is derived from the stored map and set. In the control vehicle speed range setting map, in the embodiment, when the vehicle is traveling at a relatively low speed, if the vehicle speed range in which the vehicle is repeatedly decelerated and accelerated is large (wide), the driver is likely to feel uncomfortable. In consideration, it is assumed that the control vehicle speed width ΔV is determined in advance by an experiment or the like so as to increase as the starting vehicle speed V1 increases (decreases as the starting vehicle speed V1 decreases).

Vmax = V1 + ΔV / 2 (1)
Vmin = V1-ΔV / 2 (2)

  Next, based on the set starting vehicle speed V1, an intermittent operation torque Tm2on that is an output torque of the motor MG2 when torque is output from the motor MG2 in the motor intermittent operation mode is set (step S140). In the embodiment, the intermittent operation torque Tm2on is stored in a ROM (not shown) as a intermittent operation torque setting map by predetermining the relationship between the start vehicle speed V1 and the intermittent operation torque Tm2on. When given, the corresponding intermittent operation torque Tm2on is derived from the stored map and set. In the intermittent operation torque setting map, in the embodiment, an experiment was performed in advance so that the traveling in the motor intermittent operation mode can be continued to some extent in consideration of the fact that the traveling resistance of the vehicle increases when the vehicle speed V is high. For example, the intermittent operation torque Tm2on is determined to increase as the starting vehicle speed V1 increases (to decrease as the starting vehicle speed V1 decreases). More specifically, the intermittent operation torque Tm2on of the embodiment is set to a torque larger than the torque to the drive shaft 36 necessary for traveling at a constant speed at the starting vehicle speed V1, thereby making the motor MG2 relatively efficient. It was supposed to be driven. This is based on the fact that, in the embodiment, the motor MG2 that inputs and outputs the driving power has a relatively large physique, so that the motor MG2 tends to be more efficient when a relatively large torque is output.

  When the upper and lower limit vehicle speeds Vmax and Vmin and the intermittent operation torque Tm2on are thus set, it is determined whether or not a predetermined release condition for ending the traveling in the motor intermittent operation mode is satisfied (step S150). When it is established, this routine is terminated. In the embodiment, the predetermined release condition is a condition in which any one of a plurality of conditions such as a condition that the instruction switch 89 is turned off and a condition that the brake is turned on is satisfied.

  When the predetermined release condition is not satisfied, the vehicle speed V from the vehicle speed sensor 88, the storage rate SOC of the battery 50, and the downhill indicating whether or not a certain amount of downhill is predicted in the set travel route is predicted in the future. Data necessary for control, such as the prediction flag Fd, is input (step S160). Here, the storage ratio SOC of the battery 50 is calculated from the integrated value of the charge / discharge current Ib detected by the current sensor, and is input from the battery ECU 52 by communication. In the embodiment, the downhill prediction flag Fd is map data (road data) representing a travel route set by the navigation device 90, information on a travel route estimated to be traveled in the future obtained from an advanced road traffic system (not shown), and the like. Based on the above, a value of 1 is set when recovery of the amount of charge of the battery 50 is predicted because there is a downhill of a predetermined slope or more and a predetermined distance or more during traveling after the end of traveling in the motor intermittent operation mode. The flag is set to a value of 0 when no recovery of the storage amount of the battery 50 is predicted because there is no such downhill, and the flag set by a flag setting routine (not shown) is input.

  Subsequently, a motor intermittent flag Fm, which is set to 1 when torque is output from the motor MG2 in this routine and set to 0 when output of torque from the motor MG2 is stopped, is checked (step S170). When the motor intermittent flag Fm is 0, it is determined that the vehicle is running inertially due to the inertial force of the vehicle, or the initial value (value 0) immediately after the execution of this routine is started, and the input vehicle speed V is set. It is determined whether it is higher than the lower limit vehicle speed Vmin (step S180).

  When the vehicle speed V is higher than the lower limit vehicle speed Vmin, it is determined that traveling by the inertial force of the vehicle is continued, and a value 0 is set to a torque command Tm2 * as a torque to be output from the motor MG2 (step S190). Further, it is determined whether or not the storage ratio SOC of the battery 50 is less than a predetermined threshold value Sref (step S200), and whether or not the downhill prediction flag Fd is a value 1 (step S210). If the power storage rate SOC of the battery 50 is equal to or greater than the threshold value Sref, or if the downhill prediction flag Fd is a value 1 even if the power storage rate SOC is less than the threshold value Sref, power is consumed by driving the motor MG1. Therefore, a predetermined vehicle speed reduction suppression torque Tm1set is set as a torque less than 0 (torque on the negative side) in the torque command Tm1 * as a torque to be output from the motor MG1 (step S260). On the other hand, when the storage ratio SOC of the battery 50 is less than the threshold value Sref and the downhill prediction flag Fd is 0, it is determined that power should not be consumed by driving the motor MG1, and the value of the torque command Tm1 * of the motor MG1 0 is set (step S270).

  Here, in the embodiment, the vehicle speed reduction suppression torque Tm1set does not accelerate the vehicle within a range in which the engine 22 that has been stopped is not rotated in reverse (smaller than the torque corresponding to the resistance to the traveling of the vehicle). As the torque, a constant torque determined in advance by experiments or the like is used. In addition, when the threshold value Sref is output from the motor MG1 and the vehicle speed reduction suppression torque Tm1set is consumed, it is highly necessary to increase the power storage ratio SOC of the battery 50 by power generation by the motor MG1 accompanied by the operation (combustion consumption) of the engine 22. It is for determining whether or not the energy efficiency of the vehicle is predicted to decrease, including during the driving in the engine operation mode and the motor operation mode after finishing the driving in the motor intermittent operation mode. What was obtained by experiment etc. (for example, 50%, 60% etc.) shall be used. When the downhill prediction flag Fd is a value of 1, it is determined that the electric power may be consumed by driving the motor MG1 because the power storage amount of the battery 50 is recovered by power regeneration by the motor MG2 during the future downhill travel. This is because it is predicted. Therefore, the condition that the storage ratio SOC of the battery 50 is less than the threshold value Sref and the downhill prediction flag Fd is 0 is a predetermined prediction in which recovery of the storage amount (storage ratio SOC) of the battery 50 is not predicted by future travel. It can be said that it is a condition, and it can be said a predetermined prediction condition where it is predicted that the energy efficiency of the vehicle will be reduced if the vehicle speed reduction suppression torque Tm1set is output from the motor MG1.

  When the torque commands Tm1 * and Tm2 * for the motors MG1 and MG2 are set in this way, the set torque commands Tm1 * and Tm2 * are transmitted to the motor ECU 40 (step S280), and the process returns to the release condition determination process in step S150. Receiving the torque commands Tm1 * and Tm2 *, the motor ECU 40 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 *. By such control, immediately after the execution of this routine is started, the negative vehicle speed decrease suppression torque Tm1set is output from the motor MG1 according to the success or failure of the predetermined prediction condition, and the torque corresponding to the vehicle speed decrease suppression torque Tm1set is output. While acting on the drive shaft 36, it is possible to start traveling mainly by the inertial force of the vehicle while stopping the output of torque from the motor MG2. FIG. 3 shows the mechanical relationship between the rotational speed and torque of the rotating element of the planetary gear 30 when traveling with the torque output from the motor MG2 stopped along with the output of the negative torque from the motor MG1. An example of the alignment chart shown is shown. In the figure, the left S-axis indicates the rotation speed of the sun gear, which is the rotation speed Nm1 of the motor MG1, and the C-axis indicates the rotation speed of the carrier, which is the rotation speed Ne of the engine 22 (value 0 in FIG. 3). Indicates the rotational speed Nm2 of the motor MG2, that is, the rotational speed Nr of the ring gear. A thick line arrow on the R axis indicates a torque applied to the drive shaft 36 by the torque Tm1 output from the motor MG1.

  When the vehicle speed V is equal to or lower than the lower limit vehicle speed Vmin in step S180, it is determined that the vehicle is decelerated by running with inertia of the vehicle and accelerated by torque from the motor MG2, and a value 1 is set in the motor intermittent flag Fm ( In step S220), the intermittent operation torque Tm2on is set in the torque command Tm2 * of the motor MG2 (step S240), the value 0 is set in the torque command Tm1 * of the motor MG1 (step S270), and the set torque command Tm1 * is set. , Tm2 * is transmitted to the motor ECU 40 (step S280), and the process returns to the cancellation condition determination process in step S150. By such control, it is possible to perform traveling by outputting the intermittent operation torque Tm2on from the motor MG2 as torque that can drive the motor MG2 relatively efficiently. FIG. 4 shows an example of a collinear diagram showing a dynamic relationship between the rotational speed and torque of the rotating element of the planetary gear 30 when traveling by outputting torque from the motor MG2. A thick arrow on the R axis indicates torque Tm2 output from the motor MG2 to the drive shaft 36.

  When traveling by the output of torque from the motor MG2 is started in this way, it is determined that the value is 1 in step S170. Therefore, it is determined whether or not the vehicle speed V is less than the upper limit vehicle speed Vmax (step S230), and the vehicle speed V is the upper limit vehicle speed Vmax. If it is less than the value, it is determined that the traveling by the torque output from the motor MG2 is continued, the intermittent operation torque Tm2on is set in the torque command Tm2 * of the motor MG2 (step S240), and the value of the torque command Tm1 * of the motor MG1 0 is set (step S270), the set torque commands Tm1 * and Tm2 * are transmitted to the motor ECU 40 (step S280), and the process returns to step S150.

  When the vehicle speed V is equal to or higher than the upper limit vehicle speed Vmax in step S230, it is determined that the acceleration is terminated by the torque output from the motor MG2 and the traveling with the inertial force of the vehicle is started, and a value 0 is set to the motor intermittent flag Fm. (Step S250), a value 0 is set in the motor MG2, and a torque command Tm1 * of the motor MG1 is set according to the storage ratio SOC of the battery 50 and the downhill prediction flag Fd, and the torque command Tm1 *, The process of transmitting Tm2 * is executed (steps S190 to S210, S260 to S280), and the process returns to step S150. By such control, the torque commands Tm1 * and Tm2 of the motors MG1 and MG2 are repeatedly output within the range of the control vehicle speed width ΔV until the predetermined release condition is satisfied. The * setting and transmission process are repeated.

  FIG. 5 is an explanatory diagram showing an example of a temporal change in the vehicle speed V, the output torque Tm2 from the motor MG2, and the output torque Tm1 from the motor MG1 when traveling in the motor intermittent operation mode. In the example of FIG. 5, first, when a predetermined start condition is satisfied (time t0), the torque Tm2 of the motor MG2 becomes a value 0, and a predetermined prediction in which the recovery of the charged amount of the battery 50 (the stored charge ratio SOC) is not predicted. When the condition is not satisfied, the torque Tm1 of the motor MG1 becomes the vehicle speed decrease predicted torque Tm1set with a value less than 0 (time t0-t1), and the vehicle outputs the negative vehicle speed decrease suppression torque Tm1set from the motor MG1. Due to the inertia force, the vehicle decelerates. Subsequently, when the vehicle speed V decreases to the lower limit vehicle speed Vmin of the control vehicle speed width ΔV (time t1), the torque Tm2 of the motor MG2 becomes the torque Tm2on for intermittent operation, and the torque Tm1 of the motor MG1 becomes 0 (time t1− t2), the vehicle travels at an acceleration by the torque Tm2 from the motor MG2. Next, when the vehicle speed V rises to the upper limit vehicle speed Vmax of the control vehicle speed width ΔV (time t2), the vehicle travels at a reduced speed (time t2-t3), and then accelerates within the range of the control vehicle speed width ΔV (time t3- t4) and deceleration traveling (time t4-t5) are repeated.

  As described above, in the embodiment, when accelerating traveling during traveling in the motor intermittent operation mode, the motor MG2 is driven by outputting the intermittent operation torque Tm2on that can drive the motor MG2 relatively efficiently. It is possible to travel in the motor intermittent operation mode while improving the above. Further, when traveling with the inertial force of the vehicle during traveling in the motor intermittent operation mode, the motor MG1 travels by outputting a negative vehicle speed decrease suppression torque Tm1set, that is, the driving side in which the positive and negative are reversed by the planetary gear 30. Since the (positive side) torque is output to the drive shaft 36, the distance and time for traveling (decelerating traveling) with the inertial force of the vehicle can be made longer. Moreover, as a predetermined prediction condition for predicting that the energy efficiency of the vehicle decreases when the vehicle speed decrease suppression torque Tm1set is output from the motor MG1 during this deceleration traveling, the storage ratio SOC of the battery 50 is less than the threshold value Sref. When the condition that the downhill prediction flag Fd is 0 is satisfied, the vehicle speed reduction suppression torque Tm1set is not output from the motor MG1, so that the energy efficiency of the vehicle can be improved.

  According to the hybrid vehicle 20 of the embodiment described above, when the motor MG2 performs intermittent driving traveling that travels within the range of the control vehicle speed width ΔV by repeatedly outputting torque from the motor MG2 and stopping the output, the motor MG2 While the torque output is stopped, the motors MG1 and MG2 are set by setting torque commands Tm1 * and Tm2 * of the motors MG1 and MG2 so that the vehicle MG1 outputs a vehicle speed decrease suppression torque Tm1set in a direction to suppress a decrease in vehicle speed. Therefore, it is possible to suppress a decrease in the vehicle speed V while the torque output from the motor MG2 is stopped during intermittent motor driving, and to reduce the inertial force of the vehicle while the torque output from the motor MG2 is stopped. Accordingly, the distance and time for traveling can be increased. As a result, when the motor is intermittently driven, the frequency at which the vehicle speed V is decreased and increased is reduced. For example, such a high frequency can suppress inconveniences such as giving the driver and passengers a sense of discomfort. .

  Further, in the hybrid vehicle 20 of the embodiment, when the intermittent motor driving is performed, the battery 50 is charged as a predetermined prediction condition in which the vehicle energy efficiency is predicted to decrease when the vehicle speed reduction suppression torque Tm1set is output from the motor MG1. When the ratio SOC is less than the threshold value Sref and the condition that the downhill prediction flag Fd is 0 is satisfied, control is performed so that torque is not output from the motor MG1 while the torque output from the motor MG2 is stopped. By outputting the vehicle speed decrease suppression torque Tm1set from the motor MG1 while the torque output from the motor MG2 is stopped during driving, it is possible to suppress a decrease in the energy efficiency of the vehicle.

  In the hybrid vehicle 20 of the embodiment, the vehicle speed decrease suppression torque Tm1set output from the motor MG1 uses a predetermined constant torque. However, for example, a value that tends to increase as the absolute value increases as the starting vehicle speed V1 increases. A torque of less than 0 may be used.

  In the hybrid vehicle 20 of the embodiment, the control vehicle speed width ΔV is set based on the starting vehicle speed V1, but for example, a predetermined vehicle speed width or the like may be used.

  In the hybrid vehicle 20 of the embodiment, the intermittent operation torque Tm2on output from the motor MG2 uses a torque that tends to increase as the starting vehicle speed V1 increases. For example, a predetermined constant torque or the like is used. It may be a thing.

  In the hybrid vehicle 20 of the embodiment, when a predetermined prediction condition is satisfied when the motor intermittent driving is performed, torque is not output from the motor MG1 while the output of torque from the motor MG2 is stopped. However, when the output of the torque from the motor MG2 is stopped, the torque that restricts the vehicle speed decrease suppression torque Tm1set from the motor MG1 (for example, the torque that has an absolute value smaller than 0 that is smaller than the vehicle speed decrease suppression torque Tm1set, or the vehicle speed V is the lower limit vehicle speed Vmin. Until the vehicle speed Vmin2 becomes slightly higher, the vehicle speed decrease suppression torque Tm1set is set, and thereafter, the value 0 is set until the vehicle speed V reaches the lower limit vehicle speed Vmin, thereby limiting the output of the vehicle speed decrease suppression torque Tm1set in terms of time. Torque or the like) may be output.

  In the hybrid vehicle 20 of the embodiment, as a predetermined prediction condition in which the vehicle energy efficiency is predicted to decrease when the vehicle speed decrease suppression torque Tm1set is output from the motor MG1, the storage ratio SOC of the battery 50 is less than the threshold value Sref and the downhill The condition where the prediction flag Fd has a value of 0 is used, but only the condition where the storage ratio SOC of the battery 50 is less than the threshold value Sref may be used, or the condition where the downhill prediction flag Fd has a value of 0 may be used. Good. Further, instead of the condition that the downhill prediction flag Fd is 0, that is, the condition that the stored amount of the battery 50 is not expected to recover by traveling on the downhill in the future, the future (running in the motor intermittent operation mode is terminated). In this case, it is possible to use a condition in which it is not predicted that the amount of power stored in the battery 50 will be recovered by braking at an intersection or the like during traveling (power regeneration by the motor MG2). Whether or not the brake is stepped on at the intersection can be determined based on the map data of the navigation device 90, information on the travel route obtained from the intelligent road traffic system, and the like.

  In the hybrid vehicle 20 of the embodiment, the motor 22 is intermittently operated while the operation of the engine 22 is stopped. However, the engine 22 is idling at a predetermined target state (for example, the idling speed Nidl of the engine 22). The motor may be operated intermittently while being driven in a state or the like. Even in this case, when stopping the output of torque from the motor MG2 during the intermittent motor driving, the motor MG1 outputs the vehicle speed decrease suppression torque Tm1set, and when outputting the torque from the motor MG2 during the intermittent motor driving, the torque from the motor MG1. And the intermittent operation torque Tm2on may be output from the motor MG2. FIG. 6 shows, in this modified example, the rotational speed and torque of the rotating element of the planetary gear 30 when traveling with the torque output from the motor MG2 being stopped with the output of the negative torque from the motor MG1. An example of an alignment chart showing a dynamic relationship is shown.

  In the hybrid vehicle 20 of the embodiment, the motor 22 is intermittently operated while the operation of the engine 22 is stopped. However, when the torque output from the motor MG2 is stopped during the motor intermittent operation, the engine 22 is operated. When stopping the motor and outputting torque from the motor MG2 during the intermittent motor driving, the engine 22 is started and idled at a predetermined target state (for example, the idling speed at the idling speed Nidl of the engine 22 or the idling speed Nidl or higher). The engine may be operated in a state where a slight torque is output at a predetermined target rotational speed, a state where the engine 22 is operated at an operation point where the engine 22 is efficiently operated, or the like. Even in this case, similarly to the embodiment, when stopping the output of torque from the motor MG2 during the motor intermittent operation traveling, the motor MG1 outputs the vehicle speed decrease suppression torque Tm1set, and during the motor intermittent operation traveling, the torque is output from the motor MG2. Sometimes the output of torque from the motor MG1 is stopped (or the motor MG1 outputs a slight negative torque corresponding to the slight torque of the engine 22 or the motor MG1 operates the engine 22 efficiently. It is also possible to output the intermittent operation torque Tm2on from the motor MG2 by outputting torque based on the rotational speed feedback control for rotating at the point rotational speed.

  In the hybrid vehicle 20 of the embodiment, the power from the motor MG2 is output to the drive shaft 36. However, as illustrated in the hybrid vehicle 120 of the modified example of FIG. 7, the drive shaft 36 transmits the power from the motor MG2. It may be connected to an axle (an axle connected to the wheels 39a and 39b in FIG. 7) different from the connected axle (the axle to which the drive wheels 38a and 38b are connected).

  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 a “battery”, and when the motor intermittent operation mode is running, the torque output from the motor MG2 is stopped. When the motor intermittent flag Fm is 0, the torque command Tm2 * of the motor MG2 is set to 0. In addition, the HVECU 70 and the torque command for executing the motor intermittent operation traveling control routine of FIG. 2 for setting the vehicle speed decrease suppression torque Tm1set to the torque command Tm1 * of the motor MG1 and transmitting each set value according to the success or failure of a predetermined prediction condition. The combination with the motor ECU 40 that controls the motors MG1 and MG2 with Tm1 * and Tm2 * is “motor intermittent control”. It corresponds to the stage. "

  Here, the “engine” is not limited to the engine 22 that uses gasoline, light oil, or the like as fuel, and may be another type of engine such as a hydrogen engine. The “first motor” is not limited to the motor MG1 configured as a synchronous generator motor, and may be another type of motor such as an induction motor. The “planetary gear” is not limited to the planetary gear 30, but is connected to an axle such as one using a double pinion planetary gear mechanism or a combination of a plurality of planetary gear mechanisms connected to four or more shafts. As long as three rotary elements are connected to the three axes of the drive shaft, the output shaft of the engine, and the rotary shaft of the first motor, any configuration may be used. The “second motor” is not limited to the motor MG2 configured as a synchronous generator motor, but may be other types of motors such as an induction motor as long as the rotary shaft is connected to the drive shaft. It doesn't matter. The “battery” is not limited to the battery 50 configured as a lithium ion secondary battery, and may be a nickel hydride secondary battery or any other device that exchanges power with the first motor and the second motor. The battery may be configured as a secondary battery of this type. The “motor intermittent control means” is not limited to the combination of the HVECU 70 and the motor ECU 40, and may be configured by a single electronic control unit. Further, as the “motor intermittent control means”, the value of the torque command Tm2 * of the motor MG2 is the value when the motor intermittent flag Fm that is stopping the output of torque from the motor MG2 when traveling in the motor intermittent operation mode is 0. The motor MG2 is controlled by setting 0, and the motor MG1 is controlled by setting the vehicle speed decrease suppression torque Tm1set to the torque command Tm1 * of the motor MG1 according to the success or failure of a predetermined prediction condition. When the second motor intermittent operation traveling is performed in which the torque output from the second motor and the output stop are repeated to travel within the range of the predetermined vehicle speed range, the torque output from the second motor is stopped during the second stop. If the first motor and the second motor are controlled so that the vehicle travels by outputting a vehicle speed decrease suppression torque in a direction to suppress a decrease in vehicle speed from one motor. It may be as to what made things.

  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, 120 Hybrid vehicle, 22 engine, 24 engine electronic control unit (engine ECU), 26 crankshaft, 30 planetary gear, 36 drive shaft, 37 differential gear, 38a, 38b drive wheel, 39a, 39b wheel, 40 motor electronics Control unit (motor ECU), 41, 42 inverter, 43, 44 rotational position detection sensor, 50 battery, 52 electronic control unit for battery (battery ECU), 70 electronic control unit for hybrid (HVECU), 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 Instruction switch, 90 navigation device, MG1, MG2 motor.

Claims (4)

An engine, a first motor, a planetary gear in which three rotation elements are connected to three axes of a drive shaft coupled to an axle, an output shaft of the engine, and a rotation shaft of the first motor, and rotation to the drive shaft A hybrid vehicle comprising: a second motor to which a shaft is connected; and a battery that exchanges electric power with the first motor and the second motor,
During the second motor intermittent operation traveling in which the torque output from the second motor and the output stop are repeated to travel within a predetermined vehicle speed range, the torque output from the second motor is stopped. Motor intermittent control means for controlling the first motor and the second motor so as to travel by outputting a vehicle speed decrease suppression torque in a direction to suppress a decrease in vehicle speed from the first motor;
A hybrid car with The hybrid vehicle according to claim 1,
The motor intermittent control means outputs the torque from the second motor when a predetermined prediction condition that the vehicle's energy efficiency is predicted to decrease when the vehicle speed decrease suppression torque is output from the first motor is satisfied. A means for controlling the torque output from the first motor during the stop so as to be limited by the vehicle speed decrease suppression torque;
Hybrid car. A hybrid vehicle according to claim 2,
The motor intermittent control means is means for controlling the engine so as to travel in a state where the operation of the engine is stopped,
The predetermined prediction condition is at least one of a condition in which the storage amount of the battery is less than a predetermined threshold and a predetermined battery prediction condition in which recovery of the storage amount of the battery is not predicted. is there,
Hybrid car. A hybrid vehicle according to any one of claims 1 to 3,
The motor intermittent control means starts outputting the predetermined intermittent operation torque from the second motor when the vehicle speed drops to the lower limit value of the predetermined vehicle speed width, and the vehicle speed is the upper limit of the predetermined vehicle speed width. Means for controlling the second motor so that the torque output from the second motor is stopped when the value rises to a value;
Hybrid car.

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