JP2013103577A - Drive control device of hybrid vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To avoid breakage of power generation/consumption balance in a state of traveling at a pseudo speed-change stage that is set based on the relation between the number of revolutions of an engine and a vehicle speed.SOLUTION: A derive control device is included in a hybrid vehicle which has an engine, motor, generator, and power storage device, and sets regulation number of revolutions Nemax and Nemin for regulating the number of revolutions of the engine, thereby controls the number of revolutions of the engine so that a ratio of the number of revolutions of the engine to a vehicle speed becomes constant. The derive control device includes a regulation number of revolutions changing means which changes the upper limit number of revolutions Nemax of the engine to a higher number of revolutions according to a state of a decrease in the volume of power Wout that the power storage device can output.

Description

  This invention can drive a hybrid vehicle that can continuously change a gear ratio, which is a ratio of an engine speed to a vehicle speed, and sets a pseudo gear stage that maintains the gear ratio at a predetermined value. The present invention relates to a control device.

  2. Description of the Related Art Conventionally, in a hybrid vehicle including an engine, an engine connected to a planetary gear, an output member connected to a ring gear, a first motor connected to a sun gear, and a second motor connected to the output member side A hybrid power source has been developed that travels by driving an engine using two operation lines that output different torques with respect to the engine speed.

  For example, Patent Document 1 discloses a plurality of virtual target shift stages in which the ratio of the engine speed change amount to the vehicle speed change amount is fixed, a so-called sequential shift position, and a virtual target shift step and upper and lower limit values according to the running state. A technique for appropriately setting a required torque and an engine operating point based on an execution shift stage that changes gradually is disclosed.

  Further, Patent Document 2 describes that the engine required power is changed when the input / output limit of the battery is limited during shifting of the stepped transmission provided between the second motor / generator and the drive wheels. Has been. Patent Document 3 describes that when the generated power generation increases in accordance with the shift position, the engine power is increased in addition to the limit value.

JP 2008-247073 A JP 2006-182272 A JP 2011-105259 A

  In a two-motor type hybrid vehicle, there is a difference between a change in vehicle speed during acceleration and a change in engine rotation. The technique described in the above-mentioned Patent Document 1 fixes an increase ratio between the engine speed and the vehicle speed, and controls the engine speed so as to enable an operation like a stepped shift in a pseudo manner. It was to improve the acceleration feeling felt.

  However, when the gear ratio fixed control is performed, the power that can be output from the engine is limited with respect to the torque required by the driver. Therefore, in order to realize the driver's required torque and thus the required power, the required driving force The shortage of the engine output with respect to is compensated by the motor torque by the discharge power output from the battery. At that time, the electric power stored in the battery is consumed, and the SOC (State Of Charge) indicating the state of charge of the battery is lowered. Therefore, since the shortage to satisfy the required power is compensated by the motor output, there is a possibility that the power balance continues to act negatively and the power balance is broken, and there is room for improvement.

  Therefore, the present invention has been made paying attention to the above technical problem, and in the case where a pseudo gear stage is set by maintaining a gear ratio that is a ratio between the vehicle speed and the engine speed. An object of the present invention is to provide a drive control device for a hybrid vehicle that avoids the breakdown of the power balance and realizes the power required by the driver.

  In order to achieve the above object, the invention according to claim 1 includes an internal combustion engine and a motor driven by the electric power of the power storage device as a power source, and sets a rotational speed limit for the rotational speed of the internal combustion engine. In the drive control device for a hybrid vehicle capable of controlling the rotational speed of the internal combustion engine so that the ratio of the rotational speed of the internal combustion engine to the vehicle speed is constant, the rotation of the internal combustion engine is controlled so that the ratio is constant. When the power storage device discharges to satisfy the drive request amount for the hybrid vehicle in a state where the number is controlled, the speed limit is set according to the state in which the amount of power that can be output by the power storage device decreases. The present invention is characterized in that it includes a limiting rotational speed changing means for changing the rotational speed upper limit value to the high rotational speed side.

  According to a second aspect of the present invention, in the first aspect of the invention, the limit rotation speed changing unit is configured such that a difference between the power amount and a predetermined control lower limit value related to the power storage device is smaller than a predetermined difference threshold value. Further, the hybrid vehicle drive control device is characterized in that the upper limit value of the rotational speed is changed to a higher rotational speed side in accordance with a state in which the electric energy decreases.

  The invention according to claim 3 is the hybrid vehicle according to claim 1, wherein the limit rotation speed changing means changes the rotation speed upper limit value to a higher rotation speed side when starting the discharge. This is a drive control device.

  According to a fourth aspect of the present invention, in the first aspect of the invention, the limit rotational speed changing means is smaller than a power amount threshold value that is greater than a predetermined control lower limit value for the power storage device. In this case, the rotational speed upper limit value is changed to a higher rotational speed side according to a state in which the amount of electric power is reduced.

  According to a fifth aspect of the present invention, in the invention according to any one of the first to fourth aspects, the rotational speed is released until the state in which the rotational speed of the internal combustion engine is controlled so that the ratio is constant is released. A drive control apparatus for a hybrid vehicle, characterized by comprising means for maintaining a change state of the upper limit value.

  According to the first aspect of the invention, the discharge power from the power storage device can be reduced by changing the upper limit value of the rotational speed of the internal combustion engine to the higher rotational speed side. In addition, when the engine speed is changed to a limit engine speed that allows the power to be generated for power generation, the discharge power can be reduced to zero and charging can be avoided, so that the failure of the power balance can be avoided. Therefore, even when the rotational speed of the internal combustion engine is limited, it is possible to output power that satisfies the power required by the driver while avoiding the breakdown of the power balance. Furthermore, the upper limit value of the rotational speed of the internal combustion engine can be gradually changed to the higher rotational speed side in accordance with the state in which the amount of electric power that can be output from the power storage device decreases, thereby preventing a sudden change in the rotational speed of the internal combustion engine. be able to.

  According to the second aspect of the present invention, in addition to the effect of the first aspect, the electric energy of the power storage device starts to decrease and gradually changes to the high rotation speed side according to the state in which the electric energy decreases. The uncomfortable feeling given to the driver due to the engine speed change can be reduced. Further, the state in which the amount of electric power decreases is more gradual than before the change of the rotation speed upper limit value, and a rapid consumption of electric power can be prevented.

  According to the third or fourth aspect of the invention, in addition to the effect of the first aspect, the limit rotational speed is not changed until the amount of electric power that can be output from the power storage device is reduced to some extent. It is possible to prevent the driver from feeling uncomfortable due to the change. In addition, when the amount of electric power that can be output from the power storage device approaches the control lower limit value to some extent, the upper limit value of the engine speed is changed to the higher engine speed side, so that a sudden change in the engine speed of the internal combustion engine can be prevented. Furthermore, since the rotation speed upper limit value is changed to the higher rotation speed side before the power amount becomes smaller than the control lower limit value related to the power storage device, it is possible to prevent the power amount from rapidly moving toward the control lower limit value. When the power amount of the power storage device reaches the control lower limit value, if the rotation speed upper limit value is changed to the higher rotation speed side, a sudden change in the rotation speed of the internal combustion engine can be prevented.

  According to the invention of claim 5, while maintaining the speed ratio which is the ratio of the rotational speed of the internal combustion engine to the vehicle speed, the control state in which the speed ratio is changed in a pseudo and stepwise manner is maintained. Since the change control state can be maintained when the rotation speed upper limit value related to the internal combustion engine is changed, it is possible to prevent the rotation speed upper limit value from being changed many times according to the state of the vehicle. Thereby, the uncomfortable feeling felt by the driver due to the change in the rotational speed of the internal combustion engine can be reduced.

It is the figure which showed typically the hybrid drive mechanism which is an example of the drive system in the vehicle which concerns on this invention. It is the figure which showed the change process flow of the engine speed limit at the time of the charge condition of an electrical storage apparatus reaching a control lower limit. The figure which showed the relationship between the vehicle speed of the vehicle when the charge condition of an electrical storage apparatus reached the control lower limit, the engine speed, and the outputable electric energy of the electrical storage apparatus, and the state before and after the engine speed limit change process It is. It is the figure which showed the change processing flow of the engine speed limit before the charge condition of an electrical storage apparatus reaches a control lower limit. FIG. 6 is a diagram showing the relationship between the vehicle speed of the vehicle before the state of charge of the power storage device reaches the control lower limit value, the engine speed, and the outputable electric energy of the power storage device, and the state before and after the process of changing the engine speed limit. is there. It is a collinear diagram about a power split mechanism in a two-motor type hybrid vehicle. It is the figure which showed the map for engine operating point setting which showed the relationship between an engine speed, an engine torque, and engine power.

  Embodiments of the present invention will be described below. The hybrid vehicle targeted by the present invention is a vehicle having an internal combustion engine and two generator motors as driving force sources. First, the configuration of the drive system in the vehicle will be described with reference to FIG. FIG. 1 is an example of a drive system in the vehicle, and schematically shows a hybrid drive mechanism. The vehicle 20 is a so-called two-motor type hybrid vehicle, and an engine (E / G) 1, a first motor / generator (MG 1) 2, and a second motor / generator (MG 2) 3 are connected to the power split mechanism 4. Are connected to each other. That is, the engine 1 and the first motor / generator 2 are configured to control the rotational speed of the engine 1 by the first motor / generator 2.

  The engine 1 is any one of a gasoline engine, a diesel engine, a hydrogen gas engine, a natural gas engine, and the like, and is an internal combustion engine in which a fuel consumption amount or a fuel consumption rate changes according to a rotational speed or an output torque. Therefore, the engine 1 is an internal combustion engine in which the engine speed Ne and the engine torque Te are individually controlled when driving with an emphasis on fuel efficiency. In this embodiment, the gasoline engine is the engine 1, and the engine torque Te is controlled by the intake air amount, specifically by the electronic throttle valve 12. In the case of a diesel engine, the engine torque Te is controlled by the fuel injection amount.

  The power split mechanism 4 is constituted by a planetary gear mechanism in which a plurality of rotating elements make a differential action. The power split mechanism 4 illustrated in FIG. 1 is a single pinion type planetary gear mechanism including three rotating elements. Specifically, the first motor / generator 2 is connected to a sun gear 4S that is a reaction force element in the power split mechanism 4, and a ring gear 4R that is an internal gear arranged concentrically with the sun gear 4S serves as an output element. It has become. The second motor / generator 3 is connected to the ring gear 4R. A carrier 4C holding the pinion gear meshing with the sun gear 4S and the ring gear 4R so as to rotate and revolve is an input element, and the engine 1 is connected to the carrier 4C.

  The ring gear 4R, which is an output element of the power split mechanism 4, is connected to the differential 6 via the output shaft 5, and is configured to transmit power from the differential 6 to the left and right drive wheels 7. The output shaft 5 is connected to a second motor / generator 4 for applying a driving torque to perform a power running action and for energy regeneration. A reduction gear or a transmission can be arranged between the ring gear 4R and the output shaft 5 or between the second motor / generator 3 and the output shaft 5.

  Here, an alignment chart for the power split mechanism 4 connected to the engine 1, the first motor / generator 2, and the second motor / generator 3 will be described. FIG. 6 is a collinear diagram of the power split mechanism 4 constituted by a single pinion type planetary gear mechanism. A line indicating the engine 1 connected to the carrier 4C is located between a line indicating the first motor / generator 2 connected to the sun gear 4S and a line indicating the second motor / generator 4 connected to the ring gear 4R. When the distance between the line indicating the sun gear 4S and the line indicating the carrier 4C is “1”, the line indicating the engine 1 connected to the carrier 4C and the second motor / generator 3 connected to the ring gear 4R are shown. The distance from the line corresponds to the gear ratio ρ. The gear ratio ρ is a ratio (Zs / Zr) between the number of teeth Zs of the sun gear 4S and the number of teeth Zr of the ring gear 4R in the planetary gear mechanism constituting the power split mechanism 4. The distance from the base line on each rotation element and the line indicating the connected configuration indicates the rotation speed of each rotation element, that is, the rotation speed of each configuration, and connects the points indicating the rotation speed of each rotation element and each configuration. The line becomes a straight line. Moreover, the direction shown by the arrow illustrated in FIG. 6 indicates the direction of torque of each rotating element.

  For example, in a state where the engine 1 is running with power output, as shown in FIG. 6, a so-called negative torque such as a running resistance acts on the ring gear 4R, and the carrier 4C as an input element has the engine 1 Is output, that is, the torque in the positive direction is acting. In this state, when a negative torque, that is, a torque that reduces the rotational speed of the sun gear 4S, is applied to the sun gear 4S, a positive torque obtained by amplifying the engine torque Te is applied to the ring gear 4R. The vehicle 20 travels by overcoming the negative torque. The negative torque applied to the sun gear 4S can be generated by causing the first motor / generator 2 connected thereto to function as a generator. When this first motor / generator 2 is caused to function as a generator, as is apparent from FIG. 6, if the rotation speed Nm1 of the first motor / generator 2 is decreased, the engine rotation speed Ne is decreased. On the other hand, if the rotational speed Nm1 of the first motor / generator 2 is increased, the engine rotational speed Ne is increased.

  Therefore, in the engine 1 and the first motor / generator 2 connected via the power split mechanism 4, the rotational speed Ne of the engine 1 is controlled by the first motor / generator 2. In other words, the rotational speed Ne of the engine 1 can be changed according to the rotational speed Nm1 of the first motor / generator 2, which is an electric motor having a power generation function, by the power split mechanism 4 having a differential action.

  Each of the first motor / generator 2 and the second motor / generator 3 has a function of one or both of a motor and a generator. The first motor / generator 2 functions as a generator for controlling the engine speed Ne, and can also function as an electric motor for motoring (cranking) of the engine 1, for example. In order to control these functions or operations, the first motor / generator 2 is connected to a power storage device 10 such as a battery or a capacitor via an inverter 8. The second motor / generator 3 controls the torque applied to the output shaft 5, that is, functions as a motor during power running control, or functions as a generator during energy regeneration. In order to control these functions or operations, the second motor / generator 3 is connected to the power storage device 10 via an inverter 9. Furthermore, electric power can be exchanged between the motor generators 2 and 3. The first motor / generator 2 and the second motor / generator 3 are both driven and controlled by the hybrid controller 11 via the inverters 8 and 9.

  In the vehicle 2, the first motor / generator 2 controls the rotational speed Ne of the engine 1 and uses the electric power generated by the first motor / generator 2 to cause the second motor / generator 3 to function as a motor. Thus, the driving torque is applied to the output shaft 5. The second motor / generator 3 can also perform energy regeneration. For example, when the vehicle 20 is coasting or decelerating, fuel supply and ignition to the engine 1 are stopped, and in this state, the second motor / generator 3 is driven with torque transmitted from the output shaft 5 to thereby generate a generator. To function as. As a result, the second motor / generator 3 causes the torque required for power generation to act on the output shaft 5 as a negative torque (braking torque) in a direction to stop the rotation, thereby generating a braking force.

  The power storage device 10 is a secondary battery or the like that charges and discharges electric power, and charges electric power generated by either the first motor / generator 2 or the second motor / generator 3 or supplies electric power according to insufficient output. Discharge. The power storage device 10 is managed by the hybrid controller 11 such as a charging rate and an outputable electric energy. When the power storage device 10 is a secondary battery, in order to prevent the battery from deteriorating due to overcharge or overdischarge, an appropriate intermediate region is controlled by the hybrid controller 11 in accordance with the usage status or temperature of the power storage device 10. The power storage state at is maintained. The intermediate region changes depending on temperature conditions, soundness, and the like. For example, the limit value of the amount of power that can be allowed by the power storage device 10 (power amount upper limit value) and the amount of power that can be discharged from the power storage device 10 It is the width between the limit value (the lower limit of electric energy).

  The electric power generated by the second motor / generator 3 is supplied to the power storage device 10, and the electric power for driving the second motor / generator 3 is supplied from the power storage device 10. For this reason, if the power storage device 10 is in a so-called fully charged state or a state close to this, the power generated by the second motor / generator 3 is not supplied to the power storage device 10, and the stored power amount Wout of the power storage device 10 is If it is lowered, power is not supplied to the second motor / generator 3. The electric power generated by the second motor / generator 3 may be supplied to the first motor / generator 2 via the inverters 9 and 8 and consumed as electric power to function as a motor.

  The hybrid controller 11 performs control of the output torque Te of the engine 1, that is, control of the opening degree of the electronic throttle valve 12, drive control of the motor / generators 2 and 3 via the inverters 8 and 9, and the like. The hybrid controller 11 is an electronic control unit mainly composed of a so-called microcomputer centering on a CPU (Central Processing Unit), and stores a ROM (Read Only Memory) for storing various processing programs and various data temporarily. RAM (Random Access Memory) for storing data and an interface for enabling data transmission / reception. Therefore, the hybrid controller 11 executes arithmetic processing using a program based on the input data and data stored in advance in the storage unit, and outputs a command signal to the electronic throttle valve 12 and the inverters 8 and 9. It is configured as follows. The hybrid controller 11 also includes a vehicle speed detection signal indicating the vehicle speed V, a wheel speed signal detected by the wheel speed sensor 13, an accelerator opening signal from the accelerator opening sensor 15 that detects the amount of depression of the accelerator pedal 14, and the like. Is input as data.

  The hybrid controller 11 operates as a so-called motor electronic control device or a battery electronic control device. For example, when operating as an electronic control device for a motor, various detection signals for driving and controlling the first motor / generator 2 and the second motor / generator 3 are input, switching control signals to the inverters 8 and 9, etc. Is output. Specifically, based on an input signal indicating a detection value from a rotation position detection sensor (not shown) that detects the rotation positions of the rotors of the first motor generator 2 and the second motor generator 3, the first motor generator The rotation speed Nm1 of the generator 2 and the rotation speed Nm2 of the second motor / generator 3 are calculated. Based on the calculated rotation speeds Nm1 and Nm2, the motor generators 2 and 3 are controlled so as to obtain the target rotation speeds Nm1 * and Nm2 *.

  When operating as an electronic control device for a battery, various detection signals for managing the power storage device 10 are input to the hybrid controller 11 from various sensors (not shown). For example, data such as a voltage between terminals, a charge / discharge current, and a temperature of the power storage device 10 are input. In this case, the hybrid controller 11 calculates the amount of power Wout that can be output from the power storage device 10 based on the integrated value of the charge / discharge current input from a current sensor (not shown). Charge / discharge of the power storage device 10 is managed based on the outputable electric energy Wout. For example, when the outputable power amount Wout is near the power amount upper limit value, that is, when the power storage device 10 is fully charged or close to it, the power generated by the motor generators 2 and 3 is not charged to the power storage device 10. When the outputable power amount Wout is lower than the power amount lower limit value, the power from the power storage device 10 is not supplied to the motor generators 2 and 3. The power lower limit value may be a value equal to or greater than zero. That is, when a state with a charge rate of 0% indicating complete discharge of the power storage device 20 is set as the power amount lower limit value, the power amount lower limit value is zero, and a state where the charge rate is greater than 0% Is set to a value greater than zero.

  Further, the hybrid controller 11 sets the accelerator opening Acc corresponding to the detected value from the accelerator pedal sensor 15 that detects the depression amount of the accelerator pedal 14 by the driver, and the vehicle speed V that is the speed of the vehicle 20 at that time. Based on this, the driver-requested driving force to be output to the output shaft 5 connected to the drive wheels 7, 7 is calculated. Therefore, as the operation of the vehicle 20, the engine 1 and the first motor so that the power corresponding to the driver required torque driving force, that is, the driver required power (required drive amount) Preq is transmitted to the output shaft 5 and output. -Drive control of the generator 2 and the 2nd motor generator 3 is carried out.

  Further, the engine 1 is controlled to be driven by the operating point of the engine 1 with high fuel efficiency, that is, the engine torque Te and the engine speed Ne. For example, the driving point is set with reference to a driving point setting map or the like that determines the driving condition that provides the best fuel consumption rate when the same output is obtained from the relationship between the equal fuel consumption rate line and the equal output line. The engine 1 is driven and controlled so that the driving point operates on the operation line that satisfies the driving condition, on the so-called optimum fuel consumption line Cf or in the region of high efficiency fuel consumption.

  The drive control device according to the present invention that targets the vehicle 20 described above performs pseudo step-change control based on the relationship between the engine speed Ne and the vehicle speed V, and outputs the electric energy Wout that can be output from the power storage device 10. Accordingly, the limit value (restriction speed) of the engine 1 is changed or partially released, that is, part of the limit speed is changed so that the electric power of the power storage device 10 is gradually consumed or the power storage device. Control is performed so as to avoid failure of the power balance by canceling a part of the speed limit so that it is not necessary to consume 10 electric power. This is because, in order to maintain the electric power that can be output from the power storage device 10, the engine speed Ne is mainly controlled among the operating points (operating points) of the engine 1 to avoid the breakdown of the electric power balance.

  Further, in the description of the embodiment according to the present invention, the term “pseudo” represents the control of the machine element. For example, a pseudo gear stage represents a speed ratio set and fixed on the basis of a speed ratio set by a mechanical element such as a transmission as pseudo. More specifically, the pseudo gear stage is a ratio in which the engine speed with respect to the vehicle speed is a gear ratio (pseudo gear ratio), and the ratio is fixed to a predetermined value for control. The pseudo stepped shift control is a control for performing a stepped shift in a pseudo manner, and controls stepped shift using a plurality of pseudo shift steps fixed to a plurality of predetermined values. It is.

  Furthermore, the drive control device according to the present invention is configured so that the speed of the engine 1 is such that the speed ratio of the entire vehicle becomes the pseudo speed ratio related to the currently set pseudo speed stage during traveling in the pseudo stepped speed change control. In addition to controlling Ne, the ratio of the engine speed to the vehicle speed is controlled to be constant. For example, a mechanism including the engine 1, the first motor / generator 2, and the second motor / generator 3 connected to the power split mechanism 4 is regarded as a first reduction gear or a transmission (first reduction gear), and is described above. A second reduction gear or a transmission (second reduction gear) may be disposed between the ring gear 4R and the output shaft 5 or between the second motor / generator 3 and the output shaft 5. In this case, the pseudo gear ratio in this embodiment does not indicate the gear ratio for each of the first and second reduction gears or transmissions, but is the gear ratio by the drive system of the entire vehicle. For example, under control that is fixed at a predetermined pseudo gear ratio, the rotational speed Ne of the engine 1 increases when the rotational speed of the output shaft 5 is constant, and the gear ratio (first gear ratio) associated with the first reduction gear is increased. When it becomes larger, the rotational speed transmitted to the drive wheels 7 and 7 is increased with respect to the rotational speed of the output shaft 5 to reduce the speed ratio (second speed ratio) related to the second reduction gear, and this pseudo speed ratio. Control is performed to maintain a constant value.

  Next, the operation and operation control of the vehicle 20 according to the shift position will be described. The vehicle 20 has, as shift positions selected by a shift lever (not shown), a P position that is a parking position used during parking, an R position that is a reverse position for reverse travel, an N position that is a neutral neutral position, and a normal forward movement. It has a D position that is a driving position for traveling. In addition to these shift positions, it is possible to use a pseudo stepped shift mode in which the vehicle travels at a plurality of pseudo gears (pseudo gears) in which the ratio of the engine speed Ne to the vehicle speed V (pseudo gear ratio) is fixed to a predetermined value. The S position is a sequential shift position. Therefore, the vehicle 20 equipped with the drive control device according to the present invention is a vehicle that performs automatic transmission control based on an automatic transmission or CVT, and has a stepped gear ratio that is fixed when the S position is selected. The vehicle is a hybrid vehicle equipped with a so-called sequential shiftmatic vehicle capable of selecting a quasi-stepped transmission mode that is controlled like a shift.

  The pseudo gear stage is a gear stage in which the pseudo gear ratio is fixedly controlled to a predetermined value, and is a vehicle having a plurality of pseudo gear stages each having an integer number of stages. The sequential shift position, which is the S position, is to travel by performing control that enables selection of any one of the plurality of pseudo gears. In addition to the S position, the vehicle 20 includes an upshift instruction position for upshifting an arbitrary pseudo gear stage, a downshift instruction position for downshifting, and the like, and a driver's gear stage selection based on a shift lever (not shown). An operation may be accepted. In other words, the engine speed Ne is controlled so that the ratio of the engine speed Ne to the vehicle speed V is constant by setting a limit speed to the engine speed Ne. Alternatively, a speed ratio may be set in advance for each of the plurality of pseudo gears, and the speed limit of the engine 1 may be set based on the gear ratio corresponding to the pseudo gear and the acquired vehicle speed V. . In other words, even if the obtained vehicle speed V, that is, the rotation speed of the drive wheel 7 is the same, if the pseudo gear speed at that time is different, the gear ratios thereof are different, and the limited rotation speed at those pseudo gear speeds. Are different.

  For example, when the D position is selected as the shift position, the operation is controlled so that the engine 1 is operated efficiently. This is because the driving force characteristic based on the accelerator opening of the vehicle 20 is controlled to the driving force characteristic for the D position while the D position is selected. If the S position is selected as the shift position, the operation is controlled so as to be operated in the pseudo stepped speed change mode. More specifically, when the S position is selected as the shift position of a shift lever (not shown) by the driver, one of the pseudo gears is set as the initial gear according to the vehicle speed V at that time. Further, during the selection of the S position, the driving force characteristics for the S position are controlled. After the S position is selected, for example, even when a later-described limit rotational speed is changed, as long as the shift lever is selected for the S position, the driving force characteristics for the S position are controlled. It is.

  After the initial stage is set in the pseudo-shift running mode, the pseudo-shift stage is raised by one each time the shift lever is set to the upshift instruction position. On the other hand, every time the shift lever is set to the downshift instruction position, the pseudo shift stage is lowered by one stage. Therefore, even when the traveling state changes such as increase or decrease of the vehicle speed V of the vehicle 20 while the S position is selected, that is, unless the upshift instruction position or the downshift instruction position is selected, the current position is set. The operation control in the pseudo stepped speed change mode is continued with the pseudo speed stage being maintained.

  Next, the process for partially canceling the limited rotational speed of the engine 1 will be described. The process of partially canceling the limited rotational speed described here is performed according to the power state of the power storage device 10, and in order to avoid the failure of the power balance, the driver request power Preq is set to the engine power Pe only. The rotational speed upper limit Nemax related to the rotational speed limit is canceled so that More specifically, when the amount of electric power Wout decreases to the first threshold value Woutth1, which is the control lower limit value in the power storage device 10, the upper limit value Nemax of the rotation speed is released. That is, the limited rotational speed includes the rotational speed upper limit value Nemax and the rotational speed lower limit value Nemin, and since only the restriction on the rotational speed upper limit value Nemax is canceled, the limited rotational speed is partially released. . Further, the control lower limit value is a lower limit value of the storage capacity at which the power storage device 10 can discharge power. The control lower limit value is a control lower limit value, and may be a power amount lower limit value of power storage device 10, that is, a value larger than the power storage amount zero. FIG. 2 shows a processing flow for canceling the engine speed upper limit Nemax from the engine speed Ne when the output possible power amount Wout in the power storage device 10 reaches the first threshold value Woutth1 that is the control lower limit value. FIG. The hybrid controller 11 calculates the driving force required by the driver based on the accelerator opening Acc corresponding to the depression of the accelerator pedal 14 and the vehicle speed V in the vehicle 20 at that time. Based on the driver-requested driving force and the vehicle speed V, a power Preq requested by the driver, which is a drive request amount, is calculated (step S101).

  When the power Preq requested by the driver is calculated, the hybrid controller 11 determines whether or not the current travel mode is the pseudo stepped transmission mode (step S102). For example, this traveling mode determination is made based on whether or not a shift lever (not shown) has selected the S position. Further, a vehicle state table including various vehicle data indicating the state of the vehicle 20 and the traveling state is stored in a storage unit such as a RAM, and the traveling mode item is set to the pseudo stepped transmission mode with reference to the vehicle state table. It may be determined whether or not the flag indicates the driving mode, and the traveling mode may be determined. The vehicle state table may store vehicle data such as the charging rate of the power storage device 10, the amount of power that can be charged and discharged, and the control upper and lower limit values that manage charging and discharging.

  If it is determined as a result of the travel mode determination that the mode is not the quasi-stepped transmission mode (No in step S102), the engine operation stored in advance in a storage unit such as a ROM based on the calculated driver request power Preq. Referring to the point setting map, the engine speed Ne and the engine torque Te that satisfy the driver required power Preq and operate on the operation line such as the optimum fuel consumption line Cf on the map are calculated (step S107). This processing flow is terminated without releasing the engine speed upper limit Nemax of the engine speed Ne. The engine operating point setting map is a map in which the relationship between the engine speed Ne, the engine torque Te, the iso-output line, and the operation line indicated by the optimum fuel consumption line Cf as illustrated in FIG. 7 is determined in advance. . Further, the driver required power Preq in the engine operating point setting map is indicated by any iso-output line.

  On the other hand, when it is determined as a result of the travel mode determination that it is the pseudo stepped transmission mode (Yes in step S102), the electric power that can be output from the power storage device 10 with reference to the vehicle data stored in the storage unit The amount Wout, the rotation speed upper limit value Nemax that is the upper limit rotation speed of the engine 1 and the rotation speed lower limit value Nemin that is the lower limit rotation speed are read (steps S103 and S104). These output possible electric energy Wout, the engine speed upper limit value Nemax and the engine speed lower limit value Nemin are stored in the vehicle state table together with other vehicle data, or stored in other tables and stored in the storage unit. It may be stored. Moreover, based on the control upper and lower limit values for managing the SOC and charging / discharging of the power storage device 10, the power amount Wout that can be output at that time may be calculated.

  When the outputable power amount Wout is read, it is determined whether or not the outputable power amount Wout is smaller than the first threshold value Woutth1 (step S105). The first threshold value Woutth1 is set so as to maintain electric power that can be output from the power storage device 10, and is set to a value that is larger than the lower limit value of the electric energy, for example.

  As a result of the power amount determination, if the output possible power amount Wout is equal to or greater than the first threshold value Woutth1 (No in step S105), the engine operating point setting map is referred to based on the calculated driver required power Preq, On this map, the engine speed Ne and the engine torque Te that satisfy the driver required power Preq and operate on the operation line such as the optimum fuel consumption line Cf are calculated (step S107), and the engine speed Ne of the engine speed Ne is the upper limit. This processing flow ends without releasing the value Nemax. The calculated engine rotational speed Ne is a rotational speed included in the range of the rotational speed limit, that is, the rotational speed upper limit value Nemax and the rotational speed lower limit value Nemin.

  On the other hand, if it is determined as a result of the power amount determination that the output possible power amount Wout is smaller than the first threshold value Woutth1 (Yes in step S105), the rotation that is the upper limit rotational speed of the engine speed Ne. The numerical upper limit value Nemax is canceled (step S106). This canceling process only cancels the upper limit value Nemax, which is the limit value on the rising side of the limited rotational speed, and the rotational speed lower limit value Nemin is not changed or released to either high or low speed. . By not changing or canceling the rotation speed lower limit value Nemin, it is possible to prevent the acceleration response of the vehicle 20 from being lowered. Further, the rotation speed lower limit value Nemin may change the limit rotation speed of the engine 1 before the release process of the rotation speed upper limit value Nemax.

  After canceling the rotation speed upper limit value Nemax, the hybrid controller 11 refers to an engine operating point setting map stored in advance in a storage unit such as a ROM, and the engine speed limit speed of the engine 1 that has canceled the upper limit value Nemax. And the calculated driver required power Preq, the engine speed Ne and the engine output torque Te that satisfy the driver required power Preq on the map and operate on the operation line such as the optimum fuel consumption line Cf are calculated. (Step S107), and this processing flow is terminated. The operating point determination process is determined by the output torque Te and the rotational speed Ne of the engine 1, and is set to an operating point with good fuel efficiency among operating points on a predetermined iso-output line. You can also.

  In the traveling state of the quasi stepped speed change mode, the engine speed Ne is controlled so that the ratio of the engine speed to the vehicle speed is constant. In the control state, the rotational speed Ne of the engine 1 increases so as to satisfy the pseudo gear ratio as the vehicle speed V increases due to the acceleration request from the driver. In a state where the driver required power Preq can be satisfied by the engine power Pe that can be output at the currently set speed limit of the engine 1, the discharge power Pbatout of the power storage device 10 is not used. Therefore, the power of power storage device 20 is not consumed, and outputable power amount Wout does not decrease. However, when the driver required power Preq is increased, the engine power Pe that can be output within the range of the current speed limit is not sufficient to satisfy the driver required power Preq. Discharge power Pbatout is used. Therefore, the power charged in the power storage device 10 is consumed, and the outputable power amount Wout decreases. That is, the engine speed Ne is controlled by the engine speed Pe in order to receive control of the engine speed limitation, and the discharge power Pbatout output from the power storage device 10 is used to satisfy the driver request power Preq. With the output of the discharge power Pbatout, the power of the power storage device 10 is consumed, and the outputable power amount Wout decreases.

  In the control state, since the motor generators 2 and 3 both function as motors and the power balance acts negatively, the outputable power amount Wout of the power storage device 10 continues to decrease. In other words, although the power of the power storage device 10 is consumed, the driver required power Preq is satisfied by the sum of the power (engine power) Pe output from the engine 1 and the power (discharge power) Pbatout output from the power storage device 10. . However, in order to compensate the power shortage with respect to the driver required power Preq with the discharge power Pbatout from the power storage device 10, the power that can be output from the power storage device 10 decreases, and the power balance continues to act negatively.

  Therefore, in order to avoid the breakdown of the power balance, as illustrated in FIG. 3, when the power storage device 10 and the outputtable electric energy Wout reach the first threshold value Woutth1, the engine speed upper limit value Nemax is canceled. The rotation speed upper limit value Nemax after the release is a control state in which the sum of the engine power Pe and the discharge power Pbatout taken out from the power storage device 10 satisfies the driver required power Preq and the power balance is zero or the power storage device 10 can be charged. The engine speed Ne is such that Even after the upper limit value Nemax of the engine 1 is canceled, the driving force characteristic based on the accelerator opening Acc of the vehicle 20 is controlled to the driving force characteristic for the S position, and the driving force for the D position. It is controlled differently from the characteristics.

  Further, when the quasi-stepped speed change mode is selected and the engine speed upper limit Nemax is released from the engine speed limit of the engine 1 based on the first threshold value Woutth1, the engine speed upper limit Nemax is released. Even if the state of charge of the power storage device 10 is recovered by the control, the released state of the rotation speed upper limit Nemax once executed based on the first threshold value Woutth1 is maintained, and the rotation speed Ne of the engine 1 continues to be controlled. That is, if the output possible electric energy Wout of the power storage device 10 reaches the first threshold value Woutth1 and the rotation speed upper limit value Nemax is once canceled while the pseudo stepped transmission mode is selected, the pseudo stepped transmission mode is canceled. Until this, the control state in which the rotation speed upper limit value Nemax is canceled is maintained. For example, according to the power state of the vehicle 20 or the like, the state is not automatically changed from the state where the rotation speed upper limit value Nemax is released to the control state before the release. In addition, even if the recovered output possible power amount Wout reaches the first threshold value Woutth1 again, the rotation speed upper limit Nemax may be controlled so as not to be released again. Furthermore, when the pseudo gear position is changed, or when the shift position is changed from the S position to the D position or the like, the rotation speed upper limit value Nemax may be changed.

  Next, a process of changing the engine speed limit of the engine 1 so as to prevent the sudden decrease in the output possible electric energy Wout of the power storage device 10 while satisfying the driver required power Preq will be described. In the limit rotation speed changing process described here, the rotation speed upper limit value Nemax related to the limit rotation speed of the engine 1 is gradually increased toward the high rotation speed side according to the state in which the electric energy Wout that can be output by the power storage device 10 decreases. It is a process to change continuously or continuously. Specifically, when it becomes necessary to use the discharge power Pbatout from the power storage device 10 in order to satisfy the driver required power Preq, the amount of power Wout that can be output from the power storage device 10 has started to decrease. Or when the electric energy Wout decreases to some extent, the limit rotational speed is changed to the high rotational speed side according to the state where the output possible electric energy Wout decreases. FIG. 4 is a process flow diagram for gradually or continuously changing the limit rotational speed of the engine 1 to the high rotational speed side in accordance with a state in which the amount of power Wout that can be output by the power storage device 10 decreases. Note that the detailed description of the same processing contents as the processing when the above-described outputable power amount Wout reaches the first threshold value Woutth1 will be omitted.

  The hybrid controller 11 calculates the driving force required by the driver based on the accelerator opening Acc corresponding to the depression of the accelerator pedal 14 and the vehicle speed V in the vehicle 20 at that time. Based on the driver-requested driving force and the vehicle speed V at that time, a power Preq requested by the driver, which is a drive request amount, is calculated (step S201). When the driver required power Preq is calculated, the hybrid controller 11 determines whether or not the current traveling mode is the pseudo stepped transmission mode (step S202).

  As a result of the determination of the travel mode, when it is determined that it is not the pseudo stepped transmission mode (No in step S202), the engine operation stored in advance in a storage unit such as a ROM based on the calculated driver request power Preq. With reference to the point setting map, the engine speed Ne and the engine output torque Te that satisfy the driver required power Preq on the map and operate on the operation line such as the optimum fuel consumption line Cf are calculated (step S208). Then, this processing flow is terminated without changing the engine speed limit speed.

  On the other hand, when it is determined as a result of the travel mode determination that the speed is the pseudo stepped transmission mode (Yes in step S202), the vehicle data stored in the storage unit is referred to, and the engine speed upper and lower limit values are set. Nemax and Nemin are read (step S203). The engine speed Ne changes within the range of the engine speed upper and lower limit values Nemax and Nemin. For example, an engine operating point Pe that can be output by the engine 1 is calculated based on the engine speed Ne within the range with reference to an engine operating point setting map as illustrated in FIG. More specifically, with reference to the engine operating point setting map, the optimum fuel consumption is calculated on the line that can operate on the optimum fuel consumption line Cf at the engine rotation speed Ne within the upper and lower limit values Nemax and Nemin of the limited rotation speed. The output range of the engine power Pe is a range that can be output based on the equal output line indicating the engine power Pe that intersects the line Cf. Therefore, based on the engine operating point reference map, the engine power Pe that can be output within the current speed limit is calculated.

  The calculated engine power Pe that can be output is compared with the calculated driver request power Preq, and it is determined whether or not the driver request power Preq can be satisfied with the engine power Pe (step S204). It is only necessary to determine whether or not the driver required power Preq can be satisfied only by the engine power Pe. For example, it is determined whether or not the outputable power amount Wout of the power storage device 10 starts to decrease. May be.

  If it is determined as a result of the power determination that the engine power Pe satisfies the driver required power Preq, that is, the engine power Pe is equal to or higher than the driver required power Preq (No in step S204), the calculated operation is performed. The engine operating point setting map is referred to based on the driver required power Preq, and the engine speed Ne and the engine output torque that satisfy the driver required power Preq on this map and operate on the operation line such as the optimum fuel consumption line Cf Te is calculated (step S208), and this processing flow is terminated without changing the engine speed limit speed.

  On the other hand, as a result of the power determination, when it is determined that the engine power Pe alone cannot satisfy the driver required power Preq, that is, the engine power Pe is smaller than the driver required power Preq (Yes in step S204). ), Referring to the vehicle data stored in the storage unit, reads out the electric energy Wout that can be output from the power storage device 10 (step S205). The output possible electric energy Wout stored as the vehicle data may be calculated by the hybrid controller 11 as needed and the data is rewritten.

  When the amount of electric power Wout that can be output by the power storage device 10 is read out, it is determined whether or not the outputable electric energy Wout is smaller than the second threshold value Woutth2 based on the outputable electric energy Wout (step S206). The second threshold value Woutth2 corresponds to the electric energy threshold value in the present invention, and is larger than the first threshold value Woutth1 described above. In this determination process, a comparison is made based on the outputtable power amount Wout and the second threshold value Woutth2, but the present invention is not limited to this. For example, a difference obtained by subtracting the first threshold value Woutth1 from the outputable power amount Wout may be calculated, and determination may be made based on whether this difference is smaller than a predetermined value ΔW. This predetermined value ΔW corresponds to the difference threshold in the present invention. For example, when the predetermined value ΔW> 0 is set, the rotation speed upper limit value Nemax is changed to the higher rotation speed side before the outputable electric energy Wout decreases to the first threshold value Woutth1, which is the control lower limit value of the power storage device 10. I will let you. That is, it can be said that the determination based on the difference threshold is a comparison determination between the second threshold value Woutth2 that is larger than the first threshold value Woutth1 that is the control lower limit value and the output possible electric energy Wout. Therefore, it is only necessary to determine that the outputable power amount Wout has decreased to a predetermined power amount before it becomes smaller than the first threshold value Woutth1 that is the control lower limit value.

  As a result of the power amount determination, when the outputable power amount Wout is equal to or greater than the second threshold value Woutth2 (No in step S206), the engine operating point setting map is referred to based on the calculated driver required power Preq. On this map, the engine speed Ne and the engine torque Te that satisfy the driver's required power Preq and operate on the operation line such as the optimum fuel consumption line Cf are calculated (step S208), and the engine speed limit speed is calculated. This processing flow is finished without changing.

  On the other hand, if it is determined as a result of the power amount determination that the output possible power amount Wout is smaller than the second threshold value Woutth2 (Yes in step S206), the rotation that is the upper limit rotational speed of the engine speed Ne. The number upper limit value Nemax is calculated and changed to the high rotation speed side (step S207). This limit rotation speed changing process is a partial change process for changing only the rotation speed upper limit value Nemax to the high rotation speed side out of the limit rotation speeds, and is changed according to the state in which the outputable power amount Wout decreases. The rotation speed upper limit value Nemax is calculated. Therefore, when the outputable electric energy Wout continues to decrease, the rotation speed upper limit Nemax is calculated and changed according to the decreasing state. That is, in accordance with the power state of the vehicle 20 and the state of charge of the power storage device 10, this is control for continuously changing the rotation speed upper limit value Nemax, which is a limit value on the increase side of the engine rotation speed Ne, to the high rotation speed side. It should be noted that as the outputable electric energy Wout approaches the first threshold value Woutth1, the rotation speed upper limit Nemax after the calculation change is changed to a higher rotation speed. In other words, as the difference obtained by subtracting the first threshold value Woutth1 from the output power amount Wout decreases, the amount of change in the rotation speed upper limit Nemax increases.

  The change state of the rotation speed upper limit value Nemax will be described with reference to FIG. FIG. 5 is a diagram showing the relationship among the accelerator opening Acc, the vehicle speed V, the engine speed Ne, and the outputable electric energy Wout. In a state where the driver required power Preq can be satisfied by the engine power Pe that can be output at the currently set speed limit of the engine 1, the outputable power amount Wout does not decrease, but only with the engine power Pe that can be output. When it becomes impossible to satisfy the driver required power Preq, the outputable power amount Wout decreases.

  When the driver required power Preq exceeds the engine power Pe that can be output within the current limit rotational speed, the amount of power that can be output corresponding to the insufficient power, that is, the discharge power Pbatout output from the power storage device 10 Wout decreases. Further, in the time chart illustrating the relational diagram of the output possible electric energy Wout in FIG. 5, the state in which the actual output possible electric energy Wout decreases is indicated by a solid line, and the rotation speed upper limit value Nemax remains unchanged. The transition in which the outputable power amount Wout of the power storage device 10 continues to decrease is indicated by a one-dot chain line. Furthermore, when the engine power Pe within the limit rotational speed is larger than the driver required power Preq, the power storage device 10 is not discharged and the amount of power does not decrease. Therefore, the state in which the outputable power amount Wout decreases when the rotation speed upper limit value Nemax is changed to the high rotation speed side is smaller than the state in which the outputable power amount Wout decreases when the limit rotation speed is not changed. The amount decreases gradually.

  Based on the state where the outputable power amount Wout decreases, the rotation speed upper limit value Nemax among the limited rotation speeds of the engine 1 is gradually changed to the high speed side according to the state where the outputable power amount Wout decreases. . In other words, the recalculation and resetting of the speed limit is continuously performed, and the limit value Nemax on the increase side of the engine speed Ne is gradually changed to the high speed side. It should be noted that the rotation speed lower limit value Nemin, which is the lower limit value among the limited rotation speeds, is not changed. Although not shown, when the power storage device 10 starts to discharge, that is, when the outputable electric energy Wout of the power storage device 10 starts to decrease, the rotation speed upper limit Nemax is changed to the high rotation speed side, and the output The rotational speed upper limit value Nemax may be gradually changed to the high rotational speed side according to the state where the possible power amount Wout decreases.

  Here, returning to the description of the process follow, after the engine speed upper limit value Nemax is changed in step S207, the hybrid controller 11 refers to the engine operating point setting map and changes the engine 1 limited rotation speed. The engine speed Ne and the engine output torque Te that satisfy the driver required power Preq on the map and operate on the operation line such as the optimum fuel consumption line are calculated on the basis of the number and the calculated driver required power Preq. (Step S208), and this processing flow ends.

  Note that the control (first change control) for continuously changing the rotation speed upper limit Nemax before the outputtable power Wout described above with reference to FIG. 4 or the like reaches the first threshold value Woutth1, In this control, the process is started when it approaches the first threshold value Woutth1 to some extent. Further, the control (second change control) for changing the rotation speed upper limit Nemax to a predetermined rotation speed on the high rotation speed side when the outputable power Wout described above with reference to FIG. 2 reaches the first threshold value Woutth1. ), The first change control may be executed, and the second change control may be started continuously from the first change control. As a result, the amount of change in the rotation speed upper limit Nemax that accompanies the execution of the second change control is relatively reduced compared to the case where the rotation speed upper limit value Nemax does not continue from the first change control, thereby preventing a sudden change in the engine speed Ne. it can.

  Further, when the pseudo stepped transmission mode is selected, the engine 1 is based on the difference between the outputtable electric energy Wout and the first threshold value Woutth1, or by comparing and determining the outputable electric energy Wout and the second threshold value Woutth2. When the engine speed upper limit Nemax is changed to the higher engine speed side, the changed state of the engine speed upper limit Nemax once executed is maintained, and the engine speed Ne of the engine 1 continues to be controlled. That is, if the output possible electric energy Wout of the power storage device 10 reaches the second threshold value Woutth2 and the rotation speed upper limit value Nemax is once changed to the high rotation speed side during the selection of the quasi stepped speed change mode, the quasi stepped speed change is performed. Until the mode is canceled, the control state in which the rotation speed upper limit value Nemax is changed to the high rotation speed side is maintained. For example, the rotational speed upper limit value Nemax is not automatically changed from the state changed to the high rotational speed side to the control state before the change according to the power state of the vehicle 20 or the like. FIG. 5 illustrates a case where the outputable power amount Wout continues to decrease. However, it is assumed that the power amount of the power storage device 10 increases and the recovered outputable power amount Wout reaches the second threshold value Woutth2 again. Alternatively, the rotation speed upper limit value Nemax may be controlled so as not to be changed again to the high rotation speed side. Furthermore, when the pseudo gear position is changed, or when the shift position is changed from the S position to the D position or the like, the rotation speed upper limit value Nemax may be changed.

  As described above, according to the drive control device for a hybrid vehicle according to the present invention, the rotation speed upper limit Nemax related to the engine 1 is set to the high rotation speed side according to the power state of the hybrid vehicle and the charge state of the power storage device 10. The number of rotations can be changed.

  During the engine speed limit control, that is, during traveling in the quasi-stepped speed change mode, the engine speed Ne, the engine output torque Te, and the power required by the driver, regardless of before and after the change in the limit speed of the engine 1 is changed. From the relationship among Preq, take-out power Pbatout from the power storage device 10, engine power Pe that is an equal output line, and optimum fuel consumption line Cf in the engine 1, this engine speed Ne and engine output torque Te are optimum fuel consumption lines Cf. Control to operate above is possible.

  Further, the process of changing the engine speed upper limit Nemax of the engine 1 can be performed based on each threshold value that is a limit value of the electric energy Wout that the vehicle 20 can output.

  When the maximum output speed Nemax of the engine 1 is changed once when the output possible electric energy Wout reaches the first threshold value Woutth1 while the pseudo stepped transmission mode is continuing, the speed limit is not repeated many times. Can reduce discomfort to the person.

  Even after the engine speed limit of the engine 1 is changed, the driving force characteristic based on the accelerator opening degree Acc of the vehicle 20 uses the setting of the S range and can use a setting different from the D range. .

  The drive control device for a hybrid vehicle according to the present invention is not limited to the above-described embodiment, and can be appropriately changed without departing from the object of the present invention.

  For example, although it has been described that the hybrid controller 11 functions as a motor electronic control device and a battery electronic control device, the present invention is not limited to this, and a motor electronic control device and a battery electronic device are separated from the hybrid controller 11. And a control device. Specifically, the hybrid controller 11 is electrically connected to a motor electronic control device and a battery electronic control device (not shown) so that various signals can be input and output. The motor electronic control device and the battery electronic control device are a hybrid controller. 11, the first motor / generator 2 and the second motor / generator 3 may be driven and controlled, and the power storage device 10 and the inverters 8 and 9 may be controlled.

  In the above-described embodiment, it has been described that the hybrid controller 11 manages discharge / release based on the outputable power amount Wout of the power storage device 10, but the present invention is not limited to this, and the SOC is replaced with the outputable power amount Wout. The battery may be managed based on the charging / discharging. For example, the hybrid controller 11 calculates the SOC indicating the charging rate of the power storage device 10 based on the integrated value of the charging / discharging current input from the current sensor. Based on this SOC, charge / discharge of the power storage device 10 is managed. When the SOC is near the control upper limit value, that is, when the power storage device 10 is fully charged or close to it, the power generated by the motor generators 2 and 3 is not charged to the power storage device 10. Further, when the SOC of power storage device 10 falls below the control lower limit value, power from power storage device 10 is not supplied to motor generators 2 and 3. Therefore, in order to maintain an appropriate SOC of the power storage device 10, control that mainly controls the engine speed Ne among the operating points (operating points) of the engine 1 to avoid failure of the power balance may be performed. .

  Further, the above-described power amount determination may be performed based on whether or not the output possible power amount Wout is equal to or less than the first threshold value Woutth1. This is because it is possible to set the charging rate 0% indicating the fully discharged state of the power storage device 10 as the first threshold value Woutth1, and at this time, the first threshold value Woutth1 becomes equal to the lower limit value of the electric energy and is set to zero. is there. That is, the outputable power amount Wout only needs to be less than the power amount lower limit value, and the first threshold value Woutth1 may be equal to the power amount lower limit value.

  Furthermore, the process for changing the rotational speed limit is not limited to the case where the processes are executed separately as described above, and the processes may be executed continuously. For example, after the outputable power amount Wout of the power storage device 10 starts to decrease, the power amount Wout decreases while gradually changing the rotation speed upper limit value Nemax to the high rotation speed side according to the state in which the power amount Wout decreases. When the first threshold value Woutth1 is reached, the engine speed upper limit Nemax may be canceled so that the driver required power Preq is satisfied only by the engine power Pe. At that time, in order to satisfy the driver required power Preq, the rotation speed upper limit value Nemax that has been gradually increased may be further canceled.

  Further, in the process of changing the limit rotational speed of the engine 1 so that the outputable power amount Wout is gradually reduced, the step S206 is performed after the comparison determination process between the driver required power Preq and the engine power Pe in step S204. The process of changing the rotation speed upper limit value Nemax to the high rotation speed side in step S207 based on the result of the comparison determination process between the outputable electric energy Wout of the power storage device 10 and the second threshold value Woutth2 is described. It is not limited. For example, after the comparison determination process between the driver required power Preq and the engine power Pe in step S204, the comparison determination process between the output possible electric energy Wout of the power storage device 10 and the second threshold value Woutth2 in step S206 is not performed. In the case of Yes in S204, a process of changing the rotation speed upper limit value Nemax in step S207 to the high rotation speed side may be performed. According to this, the rotation speed upper limit Nemax can be changed from when the outputable electric energy Wout of the power storage device 10 starts to decrease.

  Furthermore, in the change state of the limited rotation speed according to the present invention, the rotation speed upper limit value Nemax is changed to the high rotation speed side of the limited rotation speed before the outputable electric energy Wout of the power storage device 10 reaches the first threshold value Woutth1. In addition to the state being included, a state in which the rotation speed upper limit value Nemax of the limited rotation speed is released when the output possible electric energy Wout reaches the first threshold value Woutth1 may be included.

  Further, in the above-described embodiment, the case where the quasi stepped transmission mode is selected as the sequential shift position according to the selection operation by the shift lever as in the manual transmission has been described, but the present invention is not limited to this. . For example, the pseudo stepped transmission mode may be selected by an operation panel or an operation button installed near the driver's seat of the vehicle 20. Further, the speed change operation during the pseudo stepped speed change mode is not based on a speed change operation such as a manual transmission, but may be an automatic speed change such as an automatic transmission.

  DESCRIPTION OF SYMBOLS 1 ... Engine (E / G), 2 ... 1st motor generator (MG1), 3 ... 2nd motor generator (MG2), 4 ... Power split mechanism, 5 ... Output shaft, 6 ... Differential, 7 ... Drive wheel 8, 9 ... inverter, 10 ... power storage device, 11 ... hybrid controller, 12 ... electronic throttle valve, 13 ... wheel speed sensor, 14 ... accelerator pedal, 15 ... accelerator opening sensor.

Claims (5)

An internal combustion engine and a motor driven by the electric power of the power storage device are provided as power sources, and the ratio of the rotational speed of the internal combustion engine to the vehicle speed is made constant by setting a limit rotational speed to the rotational speed of the internal combustion engine. In the hybrid vehicle drive control device capable of controlling the rotational speed of the internal combustion engine,
In a state where the rotational speed of the internal combustion engine is controlled so that the ratio is constant,
When the power storage device discharges so as to satisfy the drive request amount for the hybrid vehicle, the rotational speed upper limit value related to the limit rotational speed is set to a high rotational speed according to a state in which the amount of power that can be output by the power storage device decreases. A drive control apparatus for a hybrid vehicle, comprising: a limit rotation speed changing means for changing the speed to the side. When the difference between the electric energy and a predetermined control lower limit value related to the power storage device is smaller than a predetermined difference threshold, the limited rotation speed changing means is configured to rotate the rotation according to a state in which the electric energy decreases. 2. The drive control apparatus for a hybrid vehicle according to claim 1, wherein the number upper limit value is changed to a higher rotation speed side. 2. The drive control apparatus for a hybrid vehicle according to claim 1, wherein the limit rotation speed changing unit changes the rotation speed upper limit value to a higher rotation speed side when starting the discharge. 3. The limit rotation speed changing means, when the power amount becomes smaller than a power amount threshold value that is a value larger than a predetermined control lower limit value related to the power storage device, according to a state in which the power amount decreases, The drive control apparatus for a hybrid vehicle according to claim 1, wherein the rotation speed upper limit value is changed to a higher rotation speed side.   2. The apparatus according to claim 1, further comprising means for maintaining a change state of the upper limit value of the rotational speed until the state in which the rotational speed of the internal combustion engine is controlled so that the ratio becomes constant is released. 4. The drive control apparatus for a hybrid vehicle according to any one of 4.